The invention relates to a compressor for air, gas or gas mixtures.

Compressors are widely used in numerous applications. Existing compressors can generate a high noise output during operation. This noise can be annoying to users and can be distracting to those in the environment of compressor operation. Non-limiting examples of compressors which generate unacceptable levels of noise output include reciprocating, rotary screw and rotary centrifugal types. Compressors which are mobile or portable and not enclosed in a cabinet or compressor room can be unacceptably noisy. However, entirely encasing a compressor, for example in a cabinet or compressor room, is expensive, prevents mobility of the compressor and is often inconvenient or not feasible. Additionally, such encasement can create heat exchange and ventilation problems. There is a strong and urgent need for a quieter compressor technology.

When a power source for a compressor is electric, gas or diesel, unacceptably high levels of unwanted heat and exhaust gases can be produced. Additionally, existing compressors can be inefficient in cooling a compressor pump and motor. Existing compressors can use multiple fans, e.g. a compressor can have one fan associated with a motor and a different fan associated with a pump. The use of multiple fans adds cost manufacturing difficulty, noise and unacceptable complexity to existing compressors. Current compressors can also have improper cooling gas flow paths which can choke cooling gas flows to the compressor and its components. Thus, there is a strong and urgent need for a more efficient cooling design for compressors.

In one aspect of the invention there is a compressor assembly, comprising: a fan; a pump assembly; a motor; a sound reduction shroud and / or a sound reduction conduit; and a sound level having a value of 75 dBA or less when the compressor assembly is in a compressing state.

Preferably the sound reduction shroud is a cylinder head shroud and the cylinder head shroud covers at least a portion of a cylinder head. Preferably the cylinder head shroud covers at least a portion of a cylinder head and at least a portion of a compressed gas outlet line. Preferably the cylinder head shroud can have a shroud coverage angle which is equal to or less than 45º. Preferably the sound reduction shroud is a pump cylinder shroud or a pump assembly shroud. Preferably wherein the pump cylinder shroud covers at least a portion of a cylinder head, at least a portion of a pump cylinder and / or at least a portion of a compressed gas outlet line. Preferably the pump cylinder shroud can have a shroud coverage angle which is in a range of 33º to 75º. Preferably the pump assembly shroud covers at least a portion of a cylinder head, at least a portion of a pump cylinder, at least a portion of the eccentric drive and / or at least a portion of a compressed gas outlet line. Preferably the pump assembly shroud can have a shroud coverage angle which is in a range of 45º to 90º.Preferably the pump assembly shroud, at least in part, provides a fillable space between the pump assembly shroud and a compressor housing into which a sound absorbing material can be placed, said fillable space filled at least in part with the sound absorbing material. Preferably the sound reduction conduit covers at least in part each of the eccentric drive, the pump assembly and the compressed gas outlet line. Preferably the sound reduction conduit provides a cooling air flow path which receives cooling air from the fan and which exhausts cooling air effluent in the direction of an exit port. Preferably the sound reduction conduit provides a cooling air channel which receives a cooling air from the fan and directs the cooling air to the motor, a cylinder head and a compressed gas outlet line.

In an embodiment, the compressor assembly disclosed herein can have a motor air duct having a blocking partition disposed along an inner surface thereof, the blocking partition configured to direct cooling air flow within the motor air duct, a conduit in flow communication with the motor air duct; and a motor cavity configured to accept a compressor assembly motor.

The air ducting shroud can have a plurality of blocking partitions. The air ducting shroud can have a blocking partition which is a front blocking partition that prevents a cooling air flow along a front portion of a pump assembly component. The air ducting shroud can have blocking partition which is a rear blocking partition that prevents a cooling air flow along a rear portion of a pump assembly component. The air ducting shroud can have three or more blocking partitions. The air ducting shroud can have four or more blocking partitions.

The air ducting shroud can have a ratio of the area of the internal cross-sectional area of the air ducting shroud to the conduit feed port and can have a value in a range of 2:1 to 50:1. The air ducting shroud according to claim 1 can have a ratio of the area of the internal cross-sectional area of the air ducting shroud to the conduit feed port can have a value greater than 11:1.

A compressor assembly can have a fan, a pump assembly, a motor and a sound reduction shroud. The compressor can have a sound level of 75 dBA or less when the compressor is in a compressing state. In an embodiment, the sound reduction shroud can be a cylinder head shroud which can cover at least a portion of a cylinder head. In another embodiment, the cylinder head shroud can cover at least a portion of the cylinder head and at least a portion of a compressed gas outlet line. The cylinder head shroud can have a shroud coverage angle of 0º to 45º, or equal to or less than 45º.

In an embodiment, the sound reduction shroud can be a pump cylinder shroud which can cover at least a portion of the cylinder head and at least a portion of a pump cylinder. In another embodiment, the pump cylinder shroud can cover at least a portion of the cylinder head, at least a portion of the pump cylinder and at least a portion of the compressed gas outlet line. The pump cylinder shroud can have a shroud coverage angle which is in a range of 33º to 75º.

In an embodiment, the sound reduction shroud can be a pump assembly shroud which can cover at least a portion of the cylinder head and at least a portion of the pump cylinder and at least a portion of the eccentric drive. In another embodiment, the pump assembly shroud can cover at least a portion of the cylinder head and at least a portion of the pump cylinder and at least a portion of the eccentric drive and at least a portion of the compressed gas outlet line. The pump assembly shroud can have a shroud coverage angle which is in a range of 45º to 90º, or greater than 90º.

In an embodiment, the pump assembly shroud can at least in part provide a fillable space between the pump assembly shroud and a compressor housing into which a sound absorbing material can be placed. The fillable space can be filled at least in part with the sound absorbing material.

In an embodiment, a compressor assembly can have the fan, the pump assembly and a sound reduction conduit. The sound reduction conduit can cover at least in part each of the eccentric drive, the pump assembly and the compressed gas outlet line. In another embodiment, the sound reduction conduit can provide a cooling air flow path which can receive cooling air from the fan and which can exhaust cooling air effluent in the direction of an exit port. In yet another embodiment, the sound reduction conduit can provide a cooling air channel which can receive a cooling air from the fan and can direct the cooling air to the motor, the cylinder head and the compressed gas outlet line.

In an embodiment, a method for compressing a gas can have the steps of: providing a compressor assembly having a motor, a pump assembly, a cylinder head and a compressed gas outlet line; providing a sound reduction shroud which covers at least a portion of the cylinder head; using the sound reduction shroud to direct toward an exhaust port at least a portion of a cooling air which flow across the cylinder head. In an embodiment, the method for compressing a gas can have the step of using the sound reduction shroud to direct at least a portion of a cooling air which flows across the motor in a direction toward an exhaust port.

The present invention in its several aspects and embodiments solves the problems discussed above and significantly advances the technology of compressors. The present invention can become more fully understood from the detailed description and the accompanying drawings, wherein:

• FIG. 1 is a perspective view of a compressor assembly;
• FIG. 2 is a front view of internal components of the compressor assembly;
• FIG. 3 is a front sectional view of the motor and fan assembly;
• FIG. 4 is a pump-side view of components of the pump assembly;
• FIG. 5 is a fan-side perspective of the compressor assembly;
• FIG. 6 is a rear perspective of the compressor assembly;
• FIG. 7 is a rear view of internal components of the compressor assembly;
• FIG. 7A is a rear view of an embodiment of a sound reduction shroud;
• FIG. 8 is a rear sectional view of the compressor assembly;
• FIG. 8A is a rear sectional view of the compressor assembly having the sound reduction shroud;
• FIG. 9 is a top view of components of the pump assembly;
• FIG. 10 is a top sectional view of the pump assembly;
• FIG. 11 is an exploded view of the air ducting shroud;
• FIG. 12 is a rear view of a valve plate assembly;
• FIG. 13 is a cross-sectional view of the valve plate assembly;
• FIG. 14 is a front view of the valve plate assembly;
• FIG. 15A is a perspective view of sound control chambers of the compressor assembly;
• FIG. 15B is a perspective view of sound control chambers having optional sound absorbers;
• FIG. 16A is a perspective view of sound control chambers with an air ducting shroud;
• FIG. 16B is a perspective view of sound control chambers having optional sound absorbers;
• FIG. 17 is a first table of embodiments of compressor assembly ranges of performance characteristics;
• FIG. 18 is a second table of embodiments of compressor assembly ranges of performance characteristics;
• FIG. 19 is a first table of example performance characteristics for an example compressor assembly;
• FIG. 20 is a second table of example performance characteristics for an example compressor assembly;
• FIG. 21 is a table containing a third example of performance characteristics of an example compressor assembly;
• FIG. 22 is a perspective view of the outer top side of an upper air ducting shroud;
• FIG. 23 is a perspective view of the inner motor side of the upper air ducting shroud;
• FIG. 24 is a fan-side view of the upper air ducting shroud;
• FIG. 25 is a view of the outer top side of an upper air ducting shroud;
• FIG. 26 is a view of the inner motor side of the upper air ducting shroud;
• FIG. 27 is a pump-side view of the upper air ducting shroud;
• FIG. 28 is a perspective view of the inner motor side of a lower air ducting shroud;
• FIG. 29 is a perspective view of the outer bottom side of a lower air ducting shroud;
• FIG. 30 is a fan-side view of the lower air ducting shroud;
• FIG. 31 is a view of the outer bottom side of a lower air ducting shroud;
• FIG. 32 is a view of the inner motor side of a lower air ducting shroud;
• FIG. 33 is a pump-side view of the lower air ducting shroud;
• FIG. 34 is a sectional view of the inner motor side of a rear section of an air ducting shroud with angled partitions;
• FIG. 35 is a perspective view of the inner motor side of a lower section of an air ducting shroud with angled partitions;
• FIG. 36 is a perspective of a fan-side view of the air ducting shroud; and
• FIG. 37 is a perspective of a pump-side view of the air ducting shroud.
• FIG. 38A is a top view of a cylinder head shroud;
• FIG. 38B is a top view of a pump cylinder shroud;
• FIG. 38C is a top view of a pump assembly shroud;
• FIG. 38D is a top view of a pump assembly shroud encased in a sound absorbing material;
• FIG. 39 is an exploded view of the air ducting shroud having the cylinder head shroud;
• FIG. 40A is a perspective of a pump-side view of the cylinder head shroud;
• FIG. 40B is a perspective of a pump-side view of the pump cylinder shroud;
• FIG. 40C is a perspective of a pump-side view of the pump assembly shroud;
• FIG. 41 is a pump end view of the sound reduction shroud having a fan shape;
• FIG. 42 is a sectional top view of components of the pump assembly showing a sound reduction conduit;
• FIG. 43 is a fan-side view of a sound reduction conduit;
• FIG. 44 is a sectional view of the motor and cooling air flow paths having a sound reduction conduit.

Herein, like references numbers in one figure refer to like reference numbers in another figure.

The invention relates to a compressor assembly which can compress air, or gas, or gas mixtures, and which has a low noise output, effective cooling means and high heat transfer. The inventive compressor assembly achieves efficient cooling of the compressor assembly 20 (FIG. 1) and/or pump assembly 25 (FIG. 2) and/or the components thereof (FIGS. 3 and 4). In an embodiment, the compressor can compress air. In another embodiment, the compressor can compress one or more gases, inert gases, or mixed gas compositions. The disclosure herein regarding compression of air is also applicable to the use of the disclosed apparatus in its many embodiments and aspects in a broad variety of services and can be used to compress a broad variety of gases and gas mixtures.

FIG. 1 is a perspective view of a compressor assembly 20 shown according to the invention. In an embodiment, the compressor assembly 20 can compress air, or can compress one or more gases, or gas mixtures. In an embodiment, the compressor assembly 20 is also referred to hearing herein as "a gas compressor assembly" or "an air compressor assembly".

The compressor assembly 20 can optionally be portable. The compressor assembly 20 can optionally have a handle 29, which optionally can be a portion of frame 10.

In an embodiment, the compressor assembly 20 can have a value of weight between 15 lbs and 100 lbs. In an embodiment, the compressor assembly 20 can be portable and can have a value of weight between 15 lbs and 50 lbs. In an embodiment, the compressor assembly 20 can have a value of weight between 25 lbs and 40 lbs. In an embodiment, the compressor assembly 20 can have a value of weight of, e.g. 38 lbs, or 29 lbs, or 27 lbs, or 25 lbs, or 20 lbs, or less. In an embodiment, frame 10 can have a value of weight of 10 lbs or less. In an embodiment, frame 10 can weigh 5 lbs, or less, e.g. 4 lbs, or 3 lbs, of 2 lbs, or less.

In an embodiment, the compressor assembly 20 can have a front side 12 ("front"), a rear side 13 ("rear"), a fan side 14 ("fan-side"), a pump side 15 ("pump-side"), a top side 16 ("top") and a bottom side 17 ("bottom").

The compressor assembly 20 can have a housing 21 which can have ends and portions which are referenced herein by orientation consistently with the descriptions set forth above. In an embodiment, the housing 21 can have a front housing 160, a rear housing 170, a fan-side housing 180 and a pump-side housing 190. The front housing 160 can have a front housing portion 161, a top front housing portion 162 and a bottom front housing potion 163. The rear housing 170 can have a rear housing portion 171, a top rear housing portion 172 and a bottom rear housing portion 173. The fan-side housing 180 can have a fan cover 181 and a plurality of intake ports 182. The compressor assembly can be cooled by air flow provided by a fan 200 (FIG. 3), e.g. cooling air stream 2000 (FIG. 3).

In an embodiment, the housing 21 can be compact and can be moulded. The housing 21 can have a construction at least in part of plastic, or polypropylene, acrylonitrile butadiene styrene (ABS), metal, steel, stamped steel, fibreglass, thermoset plastic, cured resin, carbon fibber, or other material. The frame 10 can be made of metal, steel, aluminium, carbon fibber, plastic or fibreglass.

Power can be supplied to the motor of the compressor assembly through a power cord 5 extending through the fan-side housing 180. In an embodiment, the compressor assembly 20 can comprise one or more of a cord holder member, e.g. first cord wrap 6 and second cord wrap 7 (FIG. 2).

In an embodiment, power switch 11 can be used to change the operating state of the compressor assembly 20 at least from an "on" to an "off" state, and vice versa. In an "on" state, the compressor can be in a compressing state (also herein as a "pumping state") in which it is compressing air, or a gas, or a plurality of gases, or a gas mixture.

In an embodiment, other operating modes can be engaged by power switch 11 or a compressor control system, e.g. a standby mode, or a power save mode. In an embodiment, the front housing 160 can have a dashboard 300 which provides an operator-accessible location for connections, gauges and valves which can be connected to a manifold 303 (FIG. 7). In an embodiment, the dashboard 300 can provide an operator access in non-limiting example to a first quick connection 305, a second quick connection 310, a regulated pressure gauge 315, a pressure regulator 320 and a tank pressure gauge 325. In an embodiment, a compressed gas outlet line, hose or other device to receive compressed gas can be connected the first quick connection 305 and/or second quick connection 310. In an embodiment, as shown in FIG. 1, the frame can be configured to provide an amount of protection to the dashboard 300 from the impact of objects from at least the pump-side, fan-side and top directions.

In an embodiment, the pressure regulator 320 employs a pressure regulating valve. The pressure regulator 320 can be used to adjust the pressure regulating valve 26 (FIG. 7). The pressure regulating valve 26 can be set to establish a desired output pressure. In an embodiment, excess air pressure can be can vented to atmosphere through the pressure regulating valve 26 and/or pressure relief valve 199 (FIG. 1). In an embodiment, pressure relief valve 199 can be a spring loaded safety valve. In an embodiment, the air compressor assembly 20 can be designed to provide an unregulated compressed air output.

In an embodiment, the pump assembly 25 and the compressed gas tank 150 can be connected to frame 10. The pump assembly 25, housing 21 and compressed gas tank 150 can be connected to the frame 10 by a plurality of screws and/or one or a plurality of welds and/or a plurality of connectors and/or fasteners.

The plurality of intake ports 182 can be formed in the housing 21 adjacent the housing inlet end 23 and a plurality of exhaust ports 31 can be formed in the housing 21. In an embodiment, the plurality of the exhaust ports 31 can be placed in housing 21 in the front housing portion 161. Optionally, the exhaust ports 31 can be located adjacent to the pump end of housing 21 and/or the pump assembly 25 and/or the pump cylinder 60 and/or cylinder head 61 (FIG. 2) of the pump assembly 25. In an embodiment, the exhaust ports 31 can be provided in a portion of the front housing portion 161 and in a portion of the bottom front housing portion 163.

The total cross-sectional open area of the intake ports 182 (the sum of the cross-sectional areas of the individual intake ports 182) can be a value in a range of from 3.0 in^2 to 100 in^2. In an embodiment, the total cross-sectional open area of the intake ports 182 can be a value in a range of from 6.0 in^2 to 38.81 in^2. In an embodiment, the total cross-sectional open area of the intake ports 182 can be a value in a range of from 9.8 in^2 to 25.87 in^2. In an embodiment, the total cross-sectional open area of the intake ports 182 can be 12.936 in^2.

In an embodiment, the cooling gas employed to cool compressor assembly 20 and its components can be air (also known herein as "cooling air"). The cooling air can be taken in from the environment in which the compressor assembly 20 is placed. The cooling air can be ambient from the natural environment, or air which has been conditioned or treated. The definition of "air" herein is intended to be very broad. The term "air" includes breathable air, ambient air, treated air, conditioned air, clean room air, cooled air, heated air, non-flammable oxygen containing gas, filtered air, purified air, contaminated air, air with particulates solids or water, air from bone dry (i.e. 0.00 humidity) air to air which is supersaturated with water, as well as any other type of air present in an environment in which a gas (e.g. air) compressor can be used. It is intended that cooling gases which are not air are encompassed by this disclosure. For non-limiting example, a cooling gas can be nitrogen, can comprise a gas mixture, can comprise nitrogen, can comprise oxygen (in a safe concentration), can comprise carbon dioxide, can comprise one inert gas or a plurality of inert gases, or comprise a mixture of gases.

In an embodiment, cooling air can be exhausted from compressor assembly 20 through a plurality of exhaust ports 31. The total cross-sectional open area of the exhaust ports 31 (the sum of the cross-sectional areas of the individual exhaust ports 31) can be a value in a range of from 3.0 in^2 to 100 in^2. In an embodiment, the total cross-sectional open area of the exhaust ports can be a value in a range of from 3.0 in^2 to 77.62 in^2. In an embodiment, the total cross-sectional open area of the exhaust ports can be a value in a range of from 4.0 in^2 to 38.81 in^2. In an embodiment, the total cross-sectional open area of the exhaust ports can be a value in a range of from 4.91 in^2 to 25.87 in^2. In an embodiment, the total cross-sectional open area of the exhaust ports can be 7.238 in^2.

Numeric values and ranges herein, unless otherwise stated, also are intended to have associated with them a tolerance and to account for variances of design and manufacturing, and/or operational and performance fluctuations. Thus, a number disclosed herein is intended to disclose values "about" that number. For example, a value X is also intended to be understood as "about X". Likewise, a range of Y-Z is also intended to be understood as within a range of from "about Y-about Z". Unless otherwise stated, significant digits disclosed for a number are not intended to make the number an exact limiting value. Variance and tolerance, as well as operational or performance fluctuations, are an expected aspect of mechanical design and the numbers disclosed herein are intended to be construed to allow for such factors (in non-limiting e.g., ± 10 percent of a given value). This disclosure is to be broadly construed. Likewise, the claims are to be broadly construed in their recitations of numbers and ranges.

The compressed gas tank 150 can operate at a value of pressure in a range of at least from ambient pressure, e.g. 14.7 psig to 3000 psig ("psig" is the unit lbf/in^2 gauge), or greater. In an embodiment, compressed gas tank 150 can operate at 200 psig. In an embodiment, compressed gas tank 150 can operate at 150 psig.

In an embodiment, the compressor has a pressure regulated on/off switch which can stop the pump when a set pressure is obtained. In an embodiment, the pump is activated when the pressure of the compressed gas tank 150 falls to 70 percent of the set operating pressure, e.g. to activate at 140 psig with an operating set pressure of 200 psig (140 psig = 0.70*200 psig). In an embodiment, the pump is activated when the pressure of the compressed gas tank 150 falls to 80 percent of the set operating pressure, e.g. to activate at 160 psig with an operating set pressure of 200 psig (160 psig = 0.80*200 psig). Activation of the pump can occur at a value of pressure in a wide range of set operating pressure, e.g. 25 percent to 99.5 percent of set operating pressure. Set operating pressure can also be a value in a wide range of pressure, e.g. a value in a range of from 25 psig to 3000 psig. An embodiment of set pressure can be 50 psig, 75 psig, 100 psig, 150 psig, 200 psig, 250 psig, 300 psig, 500 psig, 1000 psig, 2000 psig, 3000 psig, or greater than or less than, or a value in between these example numbers.

The compressor assembly 20 disclosed herein in its various embodiments achieves a reduction in the noise created by the vibration of the air tank while the air compressor is running, in its compressing state (pumping state) e.g. to a value in a range of from 60-75 dBA, or less, as measured by ISO3744-1995. Noise values discussed herein are compliant with ISO3744-1995. ISO3744-1995 is the standard for noise data and results for noise data, or sound data, provided in this application. Herein "noise" and "sound" are used synonymously.

The pump assembly 25 can be mounted to an air tank and can be covered with a housing 21. A plurality of optional decorative shapes 141 can be formed on the front housing portion 161. The plurality of optional decorative shapes 141 can also be sound absorbing and/or vibration dampening shapes. The plurality of optional decorative shapes 141 can optionally be used with, or contain at least in part, a sound absorbing material.

FIG. 2 is a front view of internal components of the compressor assembly.

The compressor assembly 20 can include a pump assembly 25. In an embodiment, pump assembly 25 which can compress a gas, air or gas mixture. In an embodiment in which the pump assembly 25 compresses air, it is also referred to herein as air compressor 25, or compressor 25. In an embodiment, the pump assembly 25 can be powered by a motor 33 (e.g. FIG. 3).

FIG. 2 illustrates the compressor assembly 20 with a portion of the housing 21 removed and showing the pump assembly 25. In an embodiment, the fan-side housing 180 can have a fan cover 181 and a plurality of intake ports 182. The cooling gas, for example air, can be fed through an air inlet space 184 which feeds air into the fan 200 (e.g. FIG. 3). In an embodiment, the fan 200 can be housed proximate to an air intake port 186 of an air ducting shroud 485.

Air ducting shroud 485 can have a shroud inlet scoop 484. As illustrated in FIG. 2, air ducting shroud 485 is shown encasing the fan 200 and the motor 33 (FIG. 3). In an embodiment, the shroud inlet scoop 484 can encase the fan 200, or at least a portion of the fan and at least a portion of motor 33. In this embodiment, an air inlet space 184 which feeds air into the fan 200 is shown. The air ducting shroud 485 can encase the fan 200 and the motor 33, or at least a portion of these components.

FIG. 2 is an intake muffler 900 which can receive feed air for compression (also herein as "feed air 990"; e.g. FIG. 8) via the intake muffler feed line 898. The feed air 990 can pass through the intake muffler 900 and be fed to the cylinder head 61 via the muffler outlet line 902. The feed air 990 can be compressed in pump cylinder 60 by piston 63. The piston can be provided with a seal which can function, such as slide, in the cylinder without liquid lubrication. The cylinder head 61 can be shaped to define an inlet chamber 81 (e.g. FIG. 9) and an outlet chamber 82 (e.g. FIG. 8) for a compressed gas, such as air (also known herein as "compressed air 999" or "compressed gas 999"; e.g. FIG. 10). In an embodiment, the pump cylinder 60 can be used as at least a portion of an inlet chamber 81. A gasket can form an air tight seal between the cylinder head 61 and the valve plate assembly 62 to prevent a leakage of a high pressure gas, such as compressed air 999, from the outlet chamber 82. Compressed air 999 can exit the cylinder head 61 via a compressed gas outlet port 782 and can pass through a compressed gas outlet line 145 to enter the compressed gas tank 150.

As shown in FIG. 2, the pump assembly 25 can have a pump cylinder 60, a cylinder head 61, a valve plate assembly 62 mounted between the pump cylinder 60 and the cylinder head 61, and a piston 63 which is reciprocated in the pump cylinder 60 by an eccentric drive 64 (e.g. FIG. 9). The eccentric drive 64 can include a sprocket 49 which can drive a drive belt 65 which can drive a pulley 66. A bearing 67 can be eccentrically secured to the pulley 66 by a screw, or a rod bolt 57, and a connecting rod 69. Preferably, the sprocket 49 and the pulley 66 can be spaced around their perimeters and the drive belt 65 can be a timing belt. The pulley 66 can be mounted about pulley centreline 887 and linked to a sprocket 49 by the drive belt 65 (FIG. 3) which can be configured on an axis which is represent herein as a shaft centreline 886 supported by a bracket and by a bearing 47 (FIG. 3). A bearing can allow the pulley 66 to be rotated about an axis 887 (FIG. 10) when the motor rotates the sprocket 49. As the pulley 66 rotates about the axis 887 (FIG. 10), the bearing 67 (FIG. 2) and an attached end of the connecting rod 69 are moved around a circular path.

The piston 63 can be formed as an integral part of the connecting rod 69. A compression seal can be attached to the piston 63 by a retaining ring and a screw. In an embodiment, the compression seal can be a sliding compression seal.

A cooling gas stream, such as cooling air stream 2000 (FIG. 3), can be drawn through intake ports 182 to feed fan 200. The cooling air stream 2000 can be divided into a number of different cooling air stream flows which can pass through portions of the compressor assembly and exit separately, or collectively as an exhaust air steam through the plurality of exhaust ports 31. Additionally, the cooling gas, e.g. cooling air stream 2000, can be drawn through the plurality of intake ports 182 and directed to cool the internal components of the compressor assembly 20 in a predetermined sequence to optimize the efficiency and operating life of the compressor assembly 20. The cooling air can be heated by heat transfer from compressor assembly 20 and/or the components thereof, such as pump assembly 25 (FIG. 3). The heated air can be exhausted through the plurality of exhaust ports 31.

In an embodiment, one fan can be used to cool both the pump and motor. A design using a single fan to provide cooling to both the pump and motor can require less air flow than a design using two or more fans, e.g. using one or more fans to cool the pump, and also using one or more fans to cool the motor. Using a single fan to provide cooling to both the pump and motor can reduce power requirements and also reduces noise production as compared to designs using a plurality of fans to cool the pump and the motor, or which use a plurality of fans to cool the pump assembly 25, or the compressor assembly 20.

In an embodiment, the fan blade 205 (e.g. FIG. 3) establishes a forced flow of cooling air through the internal housing, such as the air ducting shroud 485. The cooling air flow through the air ducting shroud can be a volumetric flow rate having a value of between 25 CFM to 400 CFM. The cooling air flow through the air ducting shroud can be a volumetric flow rate having a value of between 45 CFM to 125 CFM.

In an embodiment, the outlet pressure of cooling air from the fan can be in a range of from 1 psig to 50 psig. In an embodiment, the fan 200 can be a low flow fan with which generates an outlet pressure having a value in a range of from 1 in of water to 10 psi. In an embodiment, the fan 200 can be a low flow fan with which generates an outlet pressure having a value in a range of from 2 in of water to 5 psi.

In an embodiment, the air ducting shroud 485 can flow 100 CFM of cooling air with a pressure drop of from 0.0002 psi to 50 psi along the length of the air ducting shroud. In an embodiment, the air ducting shroud 485 can flow 75 CFM of cooling air with a pressure drop of 0.028 psi along its length as measured from the entrance to fan 200 through the exit from conduit 253 (FIG. 7).

In an embodiment, the air ducting shroud 485 can flow 75 CFM of cooling air with a pressure drop of 0.1 psi along its length as measured from the outlet of fan 200 through the exit from conduit 253. In an embodiment, the air ducting shroud 485 can flow 100 CFM of cooling air with a pressure drop of 1.5 psi along its length as measured from the outlet of fan 200 through the exit from conduit 253. In an embodiment, the air ducting shroud 485 can flow 150 CFM of cooling air with a pressure drop of 5.0 psi along its length as measured from the outlet of fan 200 through the exit from conduit 253.

In an embodiment, the air ducting shroud 485 can flow 75 CFM of cooling air with a pressure drop in a range of from 1.0 psi to 30 psi across as measured from the outlet of fan 200 across the motor 33.

Depending upon the compressed gas output, the design rating of the motor 33 and the operating voltage, in an embodiment, the motor 33 can operate at a value of rotation (motor speed) between 5,000 rpm and 20,000 rpm. In an embodiment, the motor 33 can operate at a value in a range of between 7,500 rpm and 12,000 rpm. In further embodiments, the motor 33 can operate at e.g.: 11,252 rpm; or 11,000 rpm; or 10,000 rpm; or 9,000 rpm; or 6,000 rpm; or 5,000 rpm. The pulley 66 and the sprocket 49 can be sized to achieve reduced pump speeds (also herein as "reciprocation rates" or "piston speed") at which the piston 63 is reciprocated. For example, if the sprocket 49 can have a diameter of 1 in and the pulley 66 can have a diameter of 4 in, then a motor 33 speed of 14,000 rpm can achieve a reciprocation rate, or a piston speed, of 3,500 strokes per minute. In an embodiment, if the sprocket 49 can have a diameter of 1.053 in and the pulley 66 can have a diameter of 5.151 in, then a motor 33 speed of 11,252 rpm can achieve a reciprocation rate, or a piston speed (pump speed), of 2,300 strokes per minute.

FIG. 3 is a front sectional view of the motor and fan assembly.

FIG. 3 illustrates the fan 200 and motor 33 covered by air ducting shroud 485. The fan 200 is shown proximate to a shroud inlet scoop 484.

The motor can have a stator 37 with an upper pole 38 around which upper stator coil 40 is wound and/or configured. The motor can have a stator 37 with a lower pole 39 around which lower stator coil 41 is wound and/or configured. A shaft 43 can be supported adjacent a first shaft end 44 by a bearing 45 and is supported adjacent to a second shaft end 46 by a bearing 47. A plurality of fan blades 205 can be secured to the fan 200 which can be secured to the first shaft end 44. When power is applied to the motor 33, the shaft 43 rotates at a high speed to in turn drive the sprocket 49 (FIG. 2), the drive belt 65 (FIG. 4), the pulley 66 (FIG. 4) and the fan blade 200. In an embodiment, the motor can be a non-synchronous universal motor. In an embodiment, the motor can be a synchronous motor used.

The compressor assembly 20 can be designed to accommodate a variety of types of motor 33. The motors 33 can come from different manufacturers and can have horsepower ratings of a value in a wide range from small to very high. In an embodiment, a motor 33 can be purchased from the existing market of commercial motors. For example, although the housing 21 is compact, In an embodiment, it can accommodate a universal motor, or other motor type, rated, for example, at 1/2 horsepower, at 3/4 horsepower or 1 horsepower by scaling and/or designing the air ducting shroud 485 to accommodate motors in a range from small to very large.

FIG. 3 and FIG. 4 illustrate the compression system for the compressor which is also referred to herein as the pump assembly 25. The pump assembly 25 can have a pump 59, a pulley 66, drive belt 65 and driving mechanism driven by motor 33. The connecting rod 69 can connect to a piston 63 (e.g. FIG. 10) which can move inside of the pump cylinder 60.

In one embodiment, the pump 59 such as "gas pump" or "air pump" can have a piston 63, a pump cylinder 60, in which a piston 63 reciprocates and a cylinder rod 69 (FIG. 2) which can optionally be oil-less and which can be driven to compress a gas, e.g. air. The pump 59 can be driven by a high speed universal motor, e.g. motor 33 (FIG. 3), or other type of motor.

FIG. 4 is a pump-side view of components of the pump assembly 25. The "pump assembly 25" can have the components which are attached to the motor and/or which serve to compress a gas; which in non-limiting example can comprise the fan, the motor 33, the pump cylinder 60 and piston 63 (and its driving parts), the valve plate assembly 62, the cylinder head 61 and the outlet of the cylinder head 782. Herein, the feed air system 905 system (FIG. 7) is referred to separately from the pump assembly 25.

FIG. 4 illustrates that pulley 66 is driven by the motor 33 using drive belt 65.

FIG. 4 (also see FIG. 10) illustrates an offset 880 which has a value of distance which represents one half (½) of the stroke distance. The offset 880 can have a value between 0.25 in and 6 in, or larger. In an embodiment, the offset 880 can have a value between 0.75 in and 3 in. In an embodiment, the offset 880 can have a value between 1.0 in and 2 in, e.g. 1.25 in. In an embodiment, the offset 880 can have a value of about 0.796 in. In an embodiment, the offset 880 can have a value of about 0.5 in. In an embodiment, the offset 880 can have a value of about 1.5 in.

A stroke having a value in a range of from 0.50 in and 12 in, or larger can be used. A stroke having a value in a range of from 1.5 in and 6 in can be used. A stroke having a value in a range of from 2 in and 4 in can be used. A stroke of 2.5 in can be used. In an embodiment, the stroke can be calculated to equal two (2) times the offset, for example an offset 880 of 0.796 produces a stroke of 2(0.796) = 1.592 in. In another example, an offset 880 of 2.25 produces a stroke of 2(2.25) = 4.5 in. In yet another example, an offset 880 of 0.5 produces a stroke of 2(0.5) = 1.0 in.

The compressed air passes through valve plate assembly 62 and into the cylinder head 61 having a plurality of cooling fins 89. The compressed gas, is discharged from the cylinder head 61 through the outlet line 145 which feeds compressed gas to the compressed gas tank 150.

FIG. 4 also identifies the pump-side of upper motor path 268 which can provide cooling air to upper stator coil 40 and lower motor path 278 which can provide cooling to lower stator coil 41.

FIG. 5 illustrates tank seal 600 providing a seal between the housing 21 and compressed gas tank 150 viewed from fan-side 14. FIG. 5 is a fan-side perspective of the compressor assembly 20. FIG. 5 illustrates a fan-side housing 180 having a fan cover 181 with intake ports 182. FIG. 5 also shows a fan-side view of the compressed gas tank 150. Tank seal 600 is illustrated sealing the housing 21 to the compressed gas tank 150. Tank seal 600 can be a one piece member or can have a plurality of segments which form tank seal 600.

FIG. 6 is a rear-side perspective of the compressor assembly 20. FIG. 6 illustrates a tank seal 600 sealing the housing 21 to the compressed gas tank 150.

FIG. 7 is a rear view of internal components of the compressor assembly. In this sectional view, in which the rear housing 170 is not shown, the fan-side housing 180 has a fan cover 181 and intake ports 182. The fan-side housing 180 is configured to feed air to air ducting shroud 485. Air ducting shroud 485 has shroud inlet scoop 484 and conduit 253 which can feed a cooling gas, such as air, to the cylinder head 61 and pump cylinder 60.

FIG. 7 also provides a view of the feed air system 905. The feed air system 905 can feed a feed air 990 through a feed air port 952 for compression in the pump cylinder 60 of pump assembly 25. The feed air port 952 can optionally receive a clean air feed from an inertia filter 949 (FIG. 8). The clean air feed can pass through the feed air port 952 to flow through an air intake hose 953 and an intake muffler feed line 898 to the intake muffler 900. The clean air can flow from the intake muffler 900 through muffler outlet line 902 and cylinder head hose 903 to feed pump cylinder head 61. Noise can be generated by the compressor pump, such as when the piston forces air in and out of the valves of valve plate assembly 62. The intake side of the pump can provide a path for the noise to escape from the compressor which intake muffler 900 can serve to muffle.

The filter distance 1952 between an inlet centreline 1950 of the feed air port 952 and a scoop inlet 1954 of shroud inlet scoop 484 can vary widely and have a value in a range of from 0.5 in to 24 in, or even greater for larger compressor assemblies. The filter distance 1952 between inlet centreline 1950 and inlet cross-section of shroud inlet scoop 484 identified as scoop inlet 1954 can be e.g. 0.5 in, or 1.0 in, or 1.5 in, or 2.0 in, or 2.5 in, or 3.0 in, or 4.0 in, or 5.0 in or 6.0 in, or greater. In an embodiment, the filter distance 1952 between inlet centreline 1950 and inlet cross-section of shroud inlet scoop 484 identified as scoop inlet 1954 can be 1.859 in. In an embodiment, the inertia filter can have multiple inlet ports which can be located at different locations of the air ducting shroud 485. In an embodiment, the inertial filter is separate from the air ducting shroud and its feed is derived from one or more inlet ports.

FIG. 7 illustrates that compressed air can exit the cylinder head 61 via the compressed gas outlet port 782 and pass through the compressed gas outlet line 145 to enter the compressed gas tank 150. FIG. 7 also shows a rear-side view of manifold 303.

FIG. 8 is a rear sectional view of the compressor assembly 20. FIG. 8 illustrates the fan cover 181 having a plurality of intake ports 182. A portion of the fan cover 181 can be extended toward the shroud inlet scoop 484, e.g. the rim 187. In this embodiment, the fan cover 181 has a rim 187 which can eliminate a visible line of sight to the air inlet space 184 from outside of the housing 21. In an embodiment, the rim 187 can cover or overlap an air space 188. FIG. 8 illustrates an inertia filter 949 having an inertia filter chamber 950 and air intake path 922.

In an embodiment, the rim 187 can extend past the air inlet space 184 and overlaps at least a portion of the shroud inlet scoop 484. In an embodiment, the rim 187 does not extend past and does not overlap a portion of the shroud inlet scoop 484 and the air inlet space 184 can have a width between the rim 187 and a portion of the shroud inlet scoop 484 having a value of distance in a range of from 0.1 in to 2 in, e.g. 0.25 in, or 0.5 in. In an embodiment, the air ducting shroud 485 and/or the shroud inlet scoop 484 can be used to block line of sight to the fan 200 and the pump assembly 25 in conjunction with or instead of the rim 187.

The inertia filter 949 can provide advantages over the use of a filter media which can become plugged with dirt and/or particles and which can require replacement to prevent degrading of compressor performance. Additionally, filter media, even when it is new, creates a pressure drop and can reduce compressor performance.

Air must make a substantial change in direction from the flow of cooling air to become compressed gas feed air to enter and pass through the feed air port 952 to enter the air intake path 922 from the inertia filter chamber 950 of the inertia filter 949. Any dust and other particles dispersed in the flow of cooling air have sufficient inertia that they tend to continue moving with the cooling air rather than change direction and enter the air intake path 922.

In an embodiment the compressor assembly 20 can have one or more sound reduction shrouds and/or sound reduction conduits. In an embodiment, the compressor assembly 20 can have a sound reduction shroud 800 (FIGS. 38A, 38B, 38C, 39, 40A, 40B, 40C and 41) which can direct cooling air flow passing across the cylinder head 61 to the exhaust ports 31. In an embodiment, the compressor assembly 20 can have a sound reduction conduit 875 (FIGS. 42, 43 and 44) which can direct cooling air flow to cool the motor 33, the pump assembly 25 and the compressed gas outlet line 145, to the exhaust ports 31.

FIG. 7A is a rear view of an embodiment of the sound reduction shroud 800. The sound reduction shroud 800 can extend over the cylinder head 61 and past the compressed gas outlet line 145. In an embodiment, the sound reduction shroud 800 can extend into the top housing portions (162, 172) and into the bottom housing portions (163, 173) to cover the compressed gas outlet line 145. The sound reduction shroud 800 can direct the cooling air exhaust from the cylinder head 61 and compressor assembly 20 toward and/or through the exhaust ports 31.

FIG. 8 also shows a section of a dampening ring 700. The dampening ring 700 can optionally have a cushion member 750, as well as optionally a first hook 710 and a second hook 720.

FIG. 8A is a rear sectional view of the compressor assembly 20 having the sound reduction shroud 800. The sound reduction shroud 800 can be shaped to extend along the top and bottom sides of the cylinder head 61 as well as to extend around a portion of the compressed gas outlet line 145.

FIG. 9 is a top view of the components of the pump assembly 25.

Pump assembly 25 can have a motor 33 which can drive the shaft 43 which causes a sprocket 49 to drive a drive belt 65 to rotate a pulley 66. The pulley 66 can be connected to and can drive the connecting rod 69 which has a piston 63 (FIG. 2) at an end. The piston 63 can compress a gas in the pump cylinder 60 pumping the compressed gas through the valve plate assembly 62 into the cylinder head 61 and then out through a compressed gas outlet port 782 through an outlet line 145 and into the compressed gas tank 150.

FIG. 9 also shows a pump 91. Herein, pump 91 collectively refers to a combination of parts including the cylinder head 61, the pump cylinder 60, the piston 63 and the connecting rod having the piston 63, as well as the components of these parts.

FIG. 10 is a top sectional view of the pump assembly 25. FIG. 10 also shows a shaft centreline 886, as well as pulley centreline 887 and a rod bolt centreline 889 of a rod bolt 57. FIG. 10 illustrates an offset 880 which can be a dimension having a value in the range of 0.5 in to 12 in, or greater. In an embodiment, the stroke can be 1.592 in, from an offset 880 of 0.796 in. FIG. 10 also shows air inlet chamber 81.

FIG. 11 is an exploded view of the air ducting shroud 485. In an embodiment, the air ducting shroud 485 can have an upper ducting shroud 481 and a lower ducting shroud 482. In the example of FIG. 11, the upper ducting shroud 481 and the lower ducting shroud 482 can be fit together to shroud the fan 200 and the motor 33 and can create air ducts for cooling pump assembly 25 and/or the compressor assembly 20. In an embodiment, the air ducting shroud 485 can also be a motor cover for motor 33. The upper air ducting shroud 481 and the lower air ducting shroud 482 can be connected by a broad variety of means which can include snaps and/or screws.

FIG. 12 is a rear-side view of a valve plate assembly. A valve plate assembly 62 is shown in detail in FIGS. 12, 13 and 14.

The valve plate assembly 62 of the pump assembly 25 can include air intake and air exhaust valves. The valves can be of a reed, flapper, one-way or other type. A restrictor can be attached to the valve plate adjacent the intake valve. Deflection of the exhaust valve can be restricted by the shape of the cylinder head which can minimize valve impact vibrations and corresponding valve stress.

The valve plate assembly 62 has a plurality of intake ports 103 (five shown) which can be closed by the intake valves 96 (FIG. 14) which can extend from fingers 105 (FIG. 13). In an embodiment, the intake valves 96 can be of the reed or "flapper" type and are formed, for example, from a thin sheet of resilient stainless steel. Radial fingers 113 (FIG. 12) can radiate from a valve finger hub 114 to connect the plurality of valve members 104 of intake valves 96 and to function as return springs. A rivet 107 secures the hub 106 (e.g. FIG. 13) to the centre of the valve plate 95. An intake valve restrictor 108 can be clamped between the rivet 107 and the hub 106. The surface 109 terminates at an edge 110 (FIGS. 13 and 14). When air is drawn into the pump cylinder 60 during an intake stroke of the piston 63, the radial fingers 113 can bend and the plurality of valve members 104 separate from the valve plate assembly 62 to allow air to flow through the intake ports 103.

FIG. 13 is a cross-sectional view of the valve plate assembly and FIG. 14 is a front-side view of the valve plate assembly. The valve plate assembly 62 includes a valve plate 95 which can be generally flat and which can mount a plurality of intake valves 96 (FIG. 14) and a plurality of outlet valves 97 (FIG. 12). In an embodiment, the valve plate assembly 62 (FIGS. 10 and 12) can be clamped to a bracket by screws which can pass through the cylinder head 61 (e.g. FIG. 2), the gasket and a plurality of through holes 99 in the valve plate assembly 62 and engage a bracket. A valve member 112 of the outlet valve 97 can cover an exhaust port 111. A cylinder flange and a gas tight seal can be used in closing the cylinder head assembly. In an embodiment, a flange and seal can be on a cylinder side (herein front-side) of a valve plate assembly 62 and a gasket can be between the valve plate assembly 62 and the cylinder head 61.

FIG. 14 illustrates the front side of the valve plate assembly 62 which can have a plurality of exhaust ports 111 (three shown) which are normally closed by the outlet valves 97. A plurality of a separate circular valve member 112 can be connected through radial fingers 113 (FIG. 12) which can be made of a resilient material to a valve finger hub 114. The valve finger hub 114 can be secured to the rear side of the valve plate assembly 62 by the rivet 107. Optionally, the cylinder head 61 can have a head rib 118 (FIG. 13) which can project over and can be spaced a distance from the valve members 112 to restrict movement of the exhaust valve members 112 and to lessen and control valve impact vibrations and corresponding valve stress.

FIG. 15A is a perspective view of a plurality of sound control chambers of an embodiment of the compressor assembly 20. FIG. 15A illustrates an embodiment having four (4) sound control chambers. The number of sound control chambers can vary widely in a range of from one to a large number, e.g. 25, or greater. In a non-limiting example, in an embodiment, a compressor assembly 20 can have a fan sound control chamber 550 (also herein as "fan chamber 550"), a pump sound control chamber 491 (also herein as "pump chamber 491 "), an exhaust sound control chamber 555 (also herein as "exhaust chamber 555"), and an upper sound control chamber 480 (also herein as "upper chamber 480").

FIG. 15B is a perspective view of sound control chambers having optional sound absorbers. The optional sound absorbers can be used to line the inner surface of housing 21, as well as both sides of partitions which are within the housing 21 of the compressor assembly 20.

FIG. 16A is a perspective view of sound control chambers with an air ducting shroud 485. FIG. 16A illustrates the placement of air ducting shroud 485 in coordination with, for example, the fan chamber 550, the pump sound control chamber 491, the exhaust sound control chamber 555, and the upper sound control chamber 480.

FIG. 16B is a perspective view of sound control chambers having optional sound absorbers. The optional sound absorbers can be used to line the inner surface of housing 21, as well as both sides of partitions which are within the housing 21 of compressor assembly 20.

FIG. 17 is a first table of embodiments of compressor assembly range of performance characteristics. The compressor assembly 20 can have values of performance characteristics as recited in FIG. 17 which are within the ranges set forth in FIG. 17.

FIG. 18 is a second table of embodiments of ranges of performance characteristics for the compressor assembly 20. The compressor assembly 20 can have values of performance characteristics as recited in FIG. 18 which are within the ranges set forth in FIG. 18.

The compressor assembly 20 achieves efficient heat transfer. The heat transfer rate can have a value in a range of from 25 BTU/min to 1000 BTU/min. The heat transfer rate can have a value in a range of from 90 BTU/min to 500 BTU/min. In an embodiment, the compressor assembly 20 can exhibit a heat transfer rate of 200 BTU/min. The heat transfer rate can have a value in a range of from 50 BTU/min to 150 BTU/min. In an embodiment, the compressor assembly 20 can exhibit a heat transfer rate of 135 BTU/min. In an embodiment, the compressor assembly 20 exhibited a heat transfer rate of 84.1 BTU/min.

The heat transfer rate of a compressor assembly 20 can have a value in a range of 60 BTU/min to 110 BTU/min. In an embodiment of the compressor assembly 20, the heat transfer rate can have a value in a range of 66.2 BTU/min to 110 BTU/min; or 60 BTU/min to 200 BTU/min.

The compressor assembly 20 can have noise emissions reduced by, for example, slower fan and/or slower motor speeds, use of a check valve muffler, use of tank vibration dampeners, use of tank sound dampeners, use of a tank dampening ring, use of tank vibration absorbers to dampen noise to and/or from the tank walls which can reduce noise. In an embodiment, a two stage intake muffler can be used on the pump. A housing having reduced or minimized openings can reduce noise from the compressor assembly. As disclosed herein, the elimination of line of sight to the fan and other components as attempted to be viewed from outside of the compressor assembly 20 can reduce noise generated by the compressor assembly. Additionally, routing cooling air through ducts, using foam lined paths and/or routing cooling air through tortuous paths can reduce noise generation by the compressor assembly 20.

Additionally, noise can be reduced from the compressor assembly 20 and its sound level lowered by one or more of the following, employing slower motor speeds, using a check valve muffler and/or using a material to provide noise dampening of the housing 21 and its partitions and/or the compressed air tank 150 heads and shell. Other noise dampening features can include one or more of the following and be used with or apart from those listed above, using a two-stage intake muffler in the feed to a feed air port 952, elimination of line of sight to the fan and/or other noise generating parts of the compressor assembly 20, a quiet fan design and/or routing cooling air routed through a tortuous path which can optionally be lined with a sound absorbing material, such as a foam. Optionally, fan 200 can be a fan which is separate from the shaft 43 and can be driven by a power source which is not shaft 43.

In an example, an embodiment of compressor assembly 20 achieved a decibel reduction of 7.5 dBA. In this example, noise output when compared to a pancake compressor assembly was reduced from about 78.5 dBA to about 71 dBA.

FIG. 19 is a first table of example performance characteristics for an example embodiment. FIG. 19 contains combinations of performance characteristics exhibited by an embodiment of compressor assembly 20.

FIG. 20 is a second table of example performance characteristics for an example embodiment. FIG. 20 contains combinations of further performance characteristics exhibited by an embodiment of compressor assembly 20.

FIG. 21 is a table containing a third example of performance characteristics of an example compressor assembly 20. In the Example of FIG. 21, a compressor assembly 20 having an air ducting shroud 485, a dampening ring 700, an intake muffler 900, four sound control chambers, a fan cover, four foam sound absorbers and a tank seal 600 exhibited the performance values set forth in FIG. 21.

The air ducting shroud 485 can be configured to segment cooling air flow, such as, for example, air flow, into streams to produce a plurality of duct air flow streams which can cool the compressor assembly 20, as well as for example the pump assembly 25 and parts thereof, e.g. pump 91 and motor 33.

In an embodiment, the air ducting shroud 485 can forms ducting that directs cooling air flow from the fan 200 across the pump and motor 33.

FIGS. 22-37 illustrate the air ducting shroud 485 for dividing the cooling air flow into three gas flows (also herein as "segments"). In an embodiment, the cooling air flow is divided into a first cooling air flow (also herein as "segment 1 "), a second cooling air flow (also herein as "segment 2") and a third cooling air flow (also herein as "segment 3").

FIG. 22 is a perspective view of the outer top side of an upper air ducting shroud. The upper air ducting shroud 481 can have an upper motor and pump cover 475 and can optionally have an upper brush pocket 211. The upper air ducting shroud 481 also has an upper portion of the conduit 253 and air feed port 952.

FIG. 23 is a perspective view of the inner motor side of the upper air ducting shroud 481 which has the upper motor and pump cover 475, as well as the conduit 253 and the air feed port 952. The motor side view of an upper brush pocket 211 is also illustrated. In an embodiment, the upper brush pocket 211 can be integrally moulded in the upper motor and pump cover and can protrude outwardly away from an outer surface thereof, leaving a hollow cavity on the inner surface of the cover. The upper brush pocket serves the purpose of providing cooling air flow to the brush as well as reducing noise emitted from the pump assembly and improving heat transfer from the pump assembly 25 by encasing the brush. FIG. 23 further illustrates an upper portion of a front blocking partition 115, an upper portion of a rear blocking partition 116, an upper portion of a front stabilizing partition 212 and an upper portion of a rear stabilizing partition 213.

The upper portion of a front blocking partition 115, the upper portion of a rear blocking partition 116, the front stabilizing partition 212 rear stabilizing partition 213, and the rear stabilizing partition 213 protrude inwardly from the inner surface of the upper motor and pump cover 475 toward a centre thereof. The lower portions of these partitions also protrude inwardly from the inner surface of the upper motor and pump cover 475 toward a centre thereof (FIG. 28)

Front stabilizing partition 212 and rear stabilizing partition 213 can be used to prevent a back flow of air along the motor from the pump-side of the pump assembly, as well as to provide additional mechanical stability to the mounting to the motor.

FIG. 24 is a fan-side view of the upper air ducting shroud 481.

FIG. 24 illustrates an upper portion of a the front blocking partition 115 and an upper portion of the rear blocking partition 116 which can be fit around an upper portion of the motor 33 to prevent air flow along the front and rear sides of the motor 33. FIG. 24 also illustrates an upper portion of a shroud inlet scoop 484.

The following dimensions of air ducting shroud are shown in FIGS. 24-36. The dimensions are example dimensions for which an air ducting shroud 485 can be designed to achieve noise reduction in a compressor assembly. The dimension provided below are intended to provide examples and ranges which will accommodate a variety of motors, fans and pumps. Further, the dimension are intended to provide examples and ranges which will achieve efficient heat transfer rates from the pump assembly 25 and parts thereof. Additionally, the dimensions below provide examples and ranges which will achieve effective and quieter air flow paths to the pump assembly 25 and parts thereof. The air ducting shroud disclosed herein is scalable and can be used in a compressor assembly of any size and having a broad variety of pump assembly designs and parts.

The air ducting shroud 485 has a shroud width 3000 which can have a dimension of 6.5 in, and optionally can be in a range of from 3.25 in to 9.75 in as measured form the front most point of the outer diameter of shroud inlet scoop 484 to the rearmost point of conduit 253. The air ducting shroud 485 has a shroud ID 3100 which can have a dimension of 3.8 in; and optionally can be in a range of from 1.9 in to 5.7 in. The air ducting shroud 485 has a motor cavity width 3090 which can have a dimension of 3.0 in; and optionally can be in a range of from 0.5 in to 12 in. The air ducting shroud 485 has a rear blocking partition width 3070 which can have a dimension of 0.44 in; and optionally can be in a range of from 0.1 in to 1.2 in. The air ducting shroud 485 has a front blocking partition width 3080 which can have a dimension of 0.44 in; and optionally can be in a range of from 0.1 in to 1.2 in. The air ducting shroud 485 has an upper conduit height 3040 which can have a dimension of 1.5 in; and optionally can be in a range of from 0.75 in to 2.25 in. The air ducting shroud 485 has a feed air port projection 3050 which can have a dimension of 0.4 in; and optionally can be in a range of from 0.2 in to 0.6 in. The air ducting shroud 485 has a scoop OD 3020 which can have a dimension of 4.659 in; and optionally can be in a range of from 2.33 in to 6.9885 in. The air ducting shroud 485 has an upper scoop width 3030 which can have a dimension of 2.3 in; and optionally can be in a range of from 1.15 in to 3.45 in. The air ducting shroud 485 has an upper duct width 3010 which can have a dimension of 2.37 in; and optionally can be in a range of from 1.19 in to 3.555 in. The air ducting shroud 485 has a brush pocket projection 3060 which can have a dimension of 0.07 in; and optionally can be in a range of from 0.04 in to 0.105 in.

FIG. 25 is a top view of the outer top side of an upper air ducting shroud 481.

The air ducting shroud 485 has a conduit length 3250 which can have a dimension of 5.3 in; and optionally can be in a range of from 2.65 in to 7.95 in. The air ducting shroud 485 has a conduit inlet width 3260 which can have a dimension of 1.6 in; and optionally can be in a range of from 0.8 in to 2.4 in. The air ducting shroud 485 has a feed air port conduit position 3270 which can have a dimension of 0.9 in; and optionally can be in a range of from 0.45 in to 1.35 in. The air ducting shroud 485 has a feed air port distance 3280 which can have a dimension of 1.9 in; and optionally can be in a range of from 0.95 in to 2.85 in. The air ducting shroud 485 has a scoop lip 3300 which can have a dimension of 0.3 in; and optionally can be in a range of from 0.15 in to 0.45 in. The air ducting shroud 485 has a brush pocket rear distance 3310 which can have a dimension of 0.6 in; and optionally can be in a range of from 0.3 in to 0.9 in. The air ducting shroud 485 has a brush pocket width 3320 which can have a dimension of 1.1 in; and optionally can be in a range of from 0.55 in to 1.65 in. The air ducting shroud 485 has a brush pocket front distance 3330 which can have a dimension of 2.4 in; and optionally can be in a range of from 1.2 in to 3.6 in. The air ducting shroud 485 has a scoop lip 3333 which can have a dimension of 0.3 in; and optionally can be in a range of from 0.15 in to 0.45 in. The air ducting shroud 485 has a brush pocket front distance 3240 which can have a dimension of 0.5 in; and optionally can be in a range of from 0.25 in to 0.75 in. The air ducting shroud 485 has a scoop length 3245 which can have a dimension of 0.6 in; and optionally can be in a range of from 0.3 in to 0.9 in. The air ducting shroud 485 has a first motor cavity length 3230 which can have a dimension of 3.1 in; and optionally can be in a range of from 1.55 in to 4.65 in. The air ducting shroud 485 has a second motor cavity length 3220 which can have a dimension of 4.7 in; and optionally can be in a range of from 2.35 in to 7.05 in. The air ducting shroud 485 has an air ducting shroud length 3210 which can have a dimension of 6.2 in; and optionally can be in a range of from 3.1 in to 9.3 in. The air ducting shroud 485 has a conduit extension 3222 which can have a dimension of 1 in; and optionally can be in a range of from 0.5 in to 1.5 in. The air ducting shroud 485 has a conduit exit width 3200 which can have a dimension of 6.22 in; and optionally can be in a range of from 1.1 in to 24 in. The air ducting shroud 485 has an air ducting shroud width 3290 which can have a dimension of 2.2 in; and optionally can be in a range of from 1.1 in to 3.3 in.

FIG. 26 is a view of the inner motor side of the upper air ducting shroud 481.

The air ducting shroud 485 has a first conduit width 3510 which can have a dimension of 0.6 in; and optionally can be in a range of from 0.3 in to 0.9 in. The air ducting shroud 485 has a second conduit width 3520 which can have a dimension of 0.8 in; and optionally can be in a range of from 0.4 in to 1.2 in. The air ducting shroud 485 has a first blocking partition distance 3450 which can have a dimension of 3.5 in; and optionally can be in a range of from 1.75 in to 5.25 in. The air ducting shroud 485 has a first blocking partition thickness 3460 which can have a dimension of 0.1 in; and optionally can be in a range of from 0.05 in to 0.15 in. The air ducting shroud 485 has a second blocking partition distance 3470 which can have a dimension of 0.9 in; and optionally can be in a range of from 0.45 in to 1.35 in. The air ducting shroud 485 has a second blocking partition thickness 3480 which can have a dimension of 0.1 in; and optionally can be in a range of from 0.05 in to 0.15 in. The air ducting shroud 485 has an end port length 3490 which can have a dimension of 0.5 in; and optionally can be in a range of from 0.25 in to 0.75 in. The air ducting shroud 485 has a conduit entrance height 3620 (Fig. 36) which can have a dimension of 1 in; and optionally can be in a range of from 0.5 in to 12 in, or greater.

FIG. 27 is a pump-side view of the upper air ducting shroud showing an upper portion of a front stabilizing partition 212 and an upper portion of a rear stabilizing partition 213.

FIG. 28 is a perspective view of the inner motor side of a lower air ducting shroud 482 having the lower motor and pump cover 476, as well as the conduit 253. Fig. 28 illustrates portal distance 3650 defined by the largest minor axis chord of the feed port to conduit 253, which in an example can have a length of 1.4 in, or a value in a range of from 0.5 in to 24 in, or greater.

FIG. 28 illustrates the motor side view of lower brush pocket 214 of the lower motor and pump cover 476. The lower motor and pump cover 476 can also have a lower portion of a front blocking partition 115 and a lower portion of a rear blocking partition 116. A lower portion of a front stabilizing partition 212 and a lower portion of a rear stabilizing partition 213. As discussed above, the front stabilizing partition 212 and the rear stabilizing partition 213 can be used to prevent a back flow of air along the motor from the pump-side of the pump assembly, as well as to provide additional mechanical stability when mounting to the motor.

FIG. 28 shows how the cooling gas flow which does not flow through conduit 253 flows though a motor conduit. In an embodiment, the flow can be directed by the use of one or more blocking partitions, such as a front blocking partition 115 and a rear blocking partition 116, or other flow directing member.

FIG. 29 is a perspective view of the outer bottom side of a lower air ducting shroud 482 illustrating a lower air ducting shroud 482 having a lower motor and pump cover 476. A lower brush pocket 214 and a lower portion of conduit 253 are also shown.

FIG. 30 is a fan-side view of the lower air ducting shroud 482.

FIG. 30 illustrates a lower portion of a front blocking partition 115 and a lower portion of a rear blocking partition 116 which can be fit around a lower portion of the motor 33 to prevent air flow along the front and rear sides of the motor 33. FIG. 30 also illustrates a lower portion of a shroud inlet scoop 484.

FIG. 31 is a view of the outer bottom side of a lower air ducting shroud.

FIG. 32 is a view of the inner motor side of a lower air ducting shroud.

FIG. 33 is a pump-side view of the lower air ducting shroud.

FIG. 34 is a sectional view of the inner motor side of a rear section of an air ducting shroud with angled partitions.

FIG. 35 is a perspective view of the inner motor side of a lower section of an air ducting shroud with angled partitions.

FIG. 36 is a perspective of a fan-side view of the air ducting shroud.

In an embodiment, an internal cross-sectional area of the air ducting shroud 3995 can have a value in a range of from 5 in^2 to 144 in^2. In an embodiment, an internal cross-sectional area of the air ducting shroud 3995 can be 12 in^2. In an embodiment, the internal cross-sectional area of the scoop 3997 can be 17 in^2. FIG. 36 also illustrates a conduit feed port 3999 from which the conduit 253 draws feed air. FIG. 36 also illustrates a motor cavity 4001 into which a compressor assembly motor can be placed.

In an embodiment, the cross-sectional area of a conduit feed port 3999 can have a value in a range of from 1.0 in^2 to 5000 in^2, or larger. In further embodiments, the area of a conduit feed port 3999 can be 2.20 in^2; or 1.6 in^2; or 36 in^2.

The ratio of the area of the internal cross-sectional area of the air ducting shroud 3995 to the conduit feed port 3999 can have a range of 2:1 to 50:1. In further embodiments, the ratio of the area of the internal cross-sectional area of the air ducting shroud 3995 to the conduit feed port 3999 can be 11:1; or 7.57:1; or 4:1; or 3.5:1; or 3:1. The ratio of the area of the internal cross-sectional area of the air ducting shroud 3995 to the conduit feed port 3999 can contribute to the balance of cooling air which flows to the various parts of the pump assembly 25. For example, the balance between how much cooling air flow cools the motor 33 and how much cooling air flow passes through conduit 253 to the cylinder head 61 area.

FIG. 37 is a perspective of a pump-side view of the air ducting shroud. In addition to other elements disclosed herein, FIG. 37 identifies a conduit support rib 3690 extending between the a portion of an outer diameter surface of air ducting shroud 485 and a portion of the conduit 253.

In an embodiment, a first cooling stream can flow across the bottom field winding and a second cooling air flow can flow across the top field winding and the head and cylinder area.

In an embodiment, the first cooling stream can flow across a first portion of the motor field windings, the second cooling stream can flow across a second portion of the motor field windings, and the third cooling stream can flow across the head and cylinder area.

In an embodiment, one fan can be used to cool both the pump and motor.

A design using a single fan to provide cooling to both the pump and motor can require less air flow than a design using one or more fans to cool the pump and one or more fans to cool the motor. Using a single fan to provide cooling to both the pump and motor reduces power requirements and also reduces noise production as compared to designs using one or more fans to cool the pump and one or more fans to cool the motor.

In an embodiment, the gas compressor uses pathways to direct the flow of cooling air to cool portions of the pump assembly 25. Cooling the pump 91 and motor 33 allows each to operate with improved efficiency and have a longer performance life.

Each of the embodiments shown in FIGS. 38A, 38B and 38C is a variation of the sound reduction shroud 800. Each of the cylinder head shroud 810 (FIG. 38A), the pump cylinder shroud 820 (FIG. 38B) and the pump assembly shroud 830 (FIG. 38C) provide a significant reduction in sound emitted from the compressor assembly 20. The sound reduction shroud 800 can have a broad variety of forms and shapes which can direct cooling air and reduce the sound emitted by the compressor assembly 20. The controlled and aerodynamic redirection toward the exhaust ports 31 of the cooling air which passes across various components of the pump assembly 25 and the compressed gas outlet line 145 reduces the sound emitted from the compressor assembly 20. Additionally, each of the various embodiments of the sound reduction shroud 800 buffer, dampen, redirect and control the turbulence and buffeting of the cooling air caused by the operation of the pump assembly and fan, as well as the impact of the cooling air against the pump-side housing 190, or other barrier to cooling air flow. Further, each of the various embodiments of the sound reduction shroud 800 can provide an additional sound barrier within the housing 21 to dampen sound emitted from the housing 21. Optionally, the sound reduction shroud 800 can be made of a hard and/or a sound absorbing material.

FIG. 38A is a top view of the cylinder head shroud 810. The cylinder head shroud 810 can be a sound reduction shroud which can be formed to cover at least a portion of the cylinder head 61. As shown in FIG. 38A, the cylinder head shroud 810 can optionally cover at least a portion of the compressed gas outlet line 145. The cylinder head shroud 810 can redirect cooling gas which flows across the cylinder head 61 to flow across the compressed gas outlet line 145 and to exit the housing 21 through the exhaust ports 31. FIG. 38A can have a shroud coverage angle 818 which can be equal to or less than 45º, such as 15º to 45º, for example 20º, and which can be sufficient to facilitate a transition and redirection of the cooling flow from across the cylinder head toward the exhaust ports 31.

In an embodiment, the cylinder head shroud 810 (FIGS. 38A and 40A) can reduce compressor assembly sound output by at least 0.5 dBA to 1.0 dBA

FIG. 38B is a top view of the pump cylinder shroud 820. The pump cylinder shroud 820 can be a sound reduction shroud which can be formed to cover the cylinder head 61 and at least a portion of the pump cylinder 60. As shown in FIG. 38B, the pump cylinder shroud 820 can optionally cover at least a portion of the compressed gas outlet line 145. The pump cylinder shroud 820 can redirect cooling gas which flows across the cylinder head 61 and the pump cylinder 60 to flow across the compressed gas outlet line 145 and to exit the housing 21 through the exhaust ports 31. Optionally, the pump cylinder shroud 820 can also redirect cooling which passes across the upper motor path 268 and/or the lower motor path 278.

FIG. 38B can have a shroud coverage angle 818 in a range of 33º to 75º, such as of 45º, and which is sufficient to facilitate a transition and redirection of the cooling flow across the cylinder head 61 and from the pump cylinder 60 toward the exhaust ports 31.

In an embodiment, the pump cylinder shroud 820 (FIG. 38B and 40B) can reduce compressor assembly sound output by at least 0.5 to 1.0 dBA.

FIG. 38C is a top view of components of the pump assembly showing a pump assembly shroud 830. The pump assembly shroud 830 can be a sound reduction shroud formed to cover the pump assembly 25. In an embodiment, the pump assembly shroud 830 can cover the cylinder head 61, the pump 91 and the compressed gas outlet line 145. In an embodiment, the pump assembly shroud 830 can cover the eccentric drive 64. The pump assembly shroud 830 can redirect cooling gas which flows across the cylinder head 61, the pump assembly 25 and the compressed gas outlet line 145 to exit the housing 21 through the exhaust ports 31. As shown in FIG. 38C, the pump assembly shroud 830 can redirect the cooling air across the eccentric drive as well as containing and controlling cooling air and the cooling air turbulence caused by the operation of the pump assembly.

FIG. 38C can have a shroud coverage angle 818 in a range of 45º to 90º, or greater 133º, such as 85º, or 90º, or 115º, and which can be sufficient to facilitate a transition and redirection of the cooling flow across the pump assembly 25 toward the exhaust ports 31.

In an embodiment, the pump assembly shroud 830 (FIGS. 38C and 40C) can reduce compressor assembly sound output by at least 0.5 to 1.0 dBA.

FIG. 38D is a top view of the pump assembly shroud 830 surround by a sound absorbing material 850. As shown in FIG. 38D, the sound reduction shroud 800, such as the pump assembly shroud 830 which can cover the pump assembly, can support a sound absorbing material 850 which can fill in part or wholly the open space within the housing 21. The sound absorbing material can be any material compatible with the operating temperatures and conditions of the compressor assembly 20. In a non-limiting example, the sound absorbing material 850 can be one or more of the following: a plastic, a polymer, a rubber, a foam, a cured resin, an acoustical foam, a sound panel or material thereof, a cellulosic material, a cardboard, a paper, a wood, a metal, a fibreglass, a porous material, a plaster, a ceramic, a fibrous material, a honeycombed material, a matrixed material, a loose packing, a formed packing, a thermoset plastic and an insulation.

In an embodiment, a formed or shaped acoustical foam can be inserted or introduced to fill in part, or wholly, open areas between the housing 21 and the pump assembly shroud 830 as well as between the housing 21 and the motor cover (475, 476). In an embodiment, surrounding the pump assembly shroud 830 and the motor cover (475, 476) with sound absorbing material 850 can reduce compressor assembly sound output by at least 0.5 dBA to 5.0 dBA, such as 1 dBA, 2 dBA or 3dBA.

FIG. 39 is an exploded view of the air ducting shroud having the cylinder head shroud 810. As shown in FIG. 39, the cylinder head shroud 810 can be of two or more parts which can be formed to enclose at least a portion of the cylinder head 61 and optionally at least a portion of the compressed gas outlet line 145. Other embodiments of the sound reduction shroud 800, such as the pump cylinder shroud 820 and/or the pump assembly shroud 830 can be similarly configured to encompass their respective portions of the pump assembly 25.

This disclosure is not limited regarding the dimensions which can be used in the embodiments of the sound reduction shroud 800 (FIGS. 40A, 40B, 40C and 41) and the sound reduction conduit 875 (FIGS. 42, 43 and 44). This disclosure is to be broadly construed regarding the dimensions of the sound reduction shroud 800 and the sound reduction conduit 875.

For example, the cylinder head shroud 810 can have a ratio of a head width 812 to a scoop height 814 of 1:1, or of 1 to greater than one. The scoop height 814 which is greater than the head width 812 reduces exhaust cooling air velocity and sound after cooling the cylinder head 61. For example, the ratio of the head width 812 to a scoop height 814 can vary over a wide range, such as 1:1.25, or 1:1.5, or 1:2, or 1:2.5, or 1:3; or 1:4, or 1:5, or 1:10. The ratio of the head width 812 to a scoop length 813 can also vary over a wide range which can improve flow regime characteristics of the exhaust cooling air and reduce sound. For example, the ratio of the head width 812 to the scoop length 813, can be in the range of 1 to less than one, or to 1:5, or 1 to greater than 5. In other examples, the ratio of the head width 812 to the scoop length 813 can be 1:0.5, or 1:0.75, 1:1, or 1:1.5, or 1:2, or 1:2.5, or 1:3, or 1:4, or 1:5, or 1:6, or 1:10.

In an embodiment, the scoop height 814 can be greater than or less than a first scoop depth 815 in and/or a second scoop depth 816. The first scoop depth 815 in and the second scoop depth 816 can have lengths which are the same or different. In an embodiment, the first scoop depth 815 and the second scoop depth 816 can be the same and can be less than the scoop height 814. The ratio of the scoop height 814 to the first scoop depth 815 to the second scoop depth 816, can range for example from 1:0.25:0.25 to 1:5:5, such as 1:0.25:0.25; 1:0.5:0.5, or 1:0.75:0.75, or 1:1:1, or 1:1.5:1.5, or 1:2:2, or 1:3:3, or 1:4:4, or 1:5:5.

The shroud length 811 can be any value necessary to accommodate the dimension(s) of the shroud and/or the equipment which the shroud covers.

FIG. 40A is a perspective of a pump-side view of the cylinder head shroud 810. As shown in FIG. 40A, the cylinder head shroud 810 can be formed to cover at least a portion of the cylinder head 61 and at least a portion of the compressed gas outlet line 145. The embodiment of FIG. 40A can have a scoop 819 which can have a fan shape and which can accommodate at least a portion of the compressed gas outlet line 145.

The embodiment of FIG. 40A can have a shroud coverage angle 818 which can be equal to or less than 45º, such as 15º to 45º, for example 20º, and which can be sufficient to facilitate a transition and redirection of the cooling flow across the cylinder head toward the exhaust ports 31. The first scoop depth 815 a second scoop depth 816 can cover at least a portion of the of the compressed gas outlet line 145.

FIG. 40B is a perspective of a pump-side view of the pump cylinder shroud 820. As shown in FIG. 40B, the pump cylinder shroud 820 can be formed to cover the cylinder head 61 and at least a portion of the pump cylinder. The embodiment of FIG. 40 can have a scoop 819 which can have a fan shape.

The embodiment of FIG. 40B can have a shroud coverage angle 818 in a range of 33º to 75º, such as of 45º, and which can be sufficient to facilitate a transition and redirection of the cooling flow across the cylinder head 61 and from the pump cylinder 60 toward the exhaust ports 31. The first scoop depth 815 a second scoop depth 816 can cover at least a portion of the of the compressed gas outlet line 145, as well as at least a portion of the cylinder head 61.

FIG. 40C is a perspective of a pump-side view of the pump assembly shroud 830. As shown in FIG. 40C, the pump assembly shroud 830 can be formed to cover the pump assembly 25 and also the compressed gas outlet line 145. The embodiment of FIG. 40 can have a scoop 819 which can have a fan shape.

The embodiment of FIG. 40C can have a shroud coverage angle 818 in a range of 45º to 90º, or greater 133º, such as 85º, or 90º, or 115 º, sufficient to facilitate a transition and redirection of the cooling flow across the pump assembly 25 toward the exhaust ports 31. The first scoop depth 815 and the second scoop depth 816 can cover at least a portion of the compressed gas outlet line 145 and pump assembly, including the eccentric drive 64.

FIG. 41 is a pump end view of the outside of the sound reduction shroud 800 having a fan shape. The embodiment of FIG. 41 is a pump end view of the sound reduction shroud 800 which can have a scoop 819 which can have a fan shape.

FIG. 42 is a top sectional view of components of the pump assembly showing a sound reduction conduit 875. In an embodiment, the sound reduction conduit 875 can be a channel which can direct the cooling air from the plurality of intake ports 182 to the exhaust ports 31.

The shroud length 821 and the scoop length 822 can have any values necessary to accommodate the dimension(s) of the shroud and/or the equipment which the conduit covers. Additionally, the sound reduction conduit 875 can have an eccentric drive cover 876 with an eccentric drive accommodation 823 which can have a pulley offset 824 and a drive offset 825.

FIG. 43 is a fan-side view of the intake-side of the fan having a sound reduction conduit 875. The eccentric drive cover 876 is shown covering the pump assembly 25.

In the embodiment depicted in FIGS. 42, 43 and 44, the sound reduction conduit 875 can reduce compressor assembly sound output by at least 0.5 dBA to 2.0 dBA.

FIG. 44 is a sectional view of the motor and cooling air flow paths having a sound reduction conduit 875. FIG. 44 shows the sound reduction conduit channelling cooling air from a variety of sources, such as the feed pump stream 254, the upper motor stream 270, the lower motor stream 280 and/or the motor gap 240, to the exhaust ports 31.

In an embodiment, the sound reduction conduit 875 can be a generally tubular channel and open on an inlet end 878 and an exhaust end 978.

In an embodiment, the sound reduction conduit 875 can be a generally closed channel which controls air flow along the cooling path for the motor 33, cylinder head 61, pump assembly 25 and the compressed gas outlet line 145. The sound reduction conduit 875 can smooth out air flow, reduce turbulence and significantly reduce sound caused by turbulent and/or other air flow. Additionally, the sound reduction conduit 875 can provide a hard and/or a sound absorbing barrier against sound and which can be in part or wholly within the housing 21. In an embodiment, open space(s) between the outside surface of the sound reduction conduit 875 and the inside of the housing 21 can be packed in part or wholly with the sound absorbing material 850.

In the conduit embodiment of FIG. 44, the sound reduction conduit 875 in conjunction with the use of a sound absorbing material 850 filling in part, or wholly, the fillable space or spaces between the sound reduction conduit 875 and the housing 21 can reduce compressor assembly sound output by at least 0.5 to 5.0 dBA, such as 1 dBA, 2 dBA or 3 dBA.

The scope of this disclosure is to be broadly construed. It is intended that this disclosure disclose equivalents, means, systems and methods to achieve the devices, designs, operations, control systems, controls, activities, mechanical actions, fluid dynamics and results disclosed herein. For each mechanical element or mechanism disclosed, it is intended that this disclosure also encompasses within the scope of its disclosure and teaches equivalents, means, systems and methods for practicing the many aspects, mechanisms and devices disclosed herein. Additionally, this disclosure regards a compressor and its many aspects, features and elements. Such an apparatus can be dynamic in its use and operation. This disclosure is intended to encompass the equivalents, means, systems and methods of the use of the compressor assembly and its many aspects consistent with the description and spirit of the apparatus, means, methods, functions and operations disclosed herein. The claims of this application are likewise to be broadly construed.

The description of the inventions herein in their many embodiments is merely exemplary in nature and, thus, variations that do not depart from the gist of the invention are intended to be within the scope of the invention and the disclosure herein. Such variations are not to be regarded as a departure from the spirit and scope of the invention.

It will be appreciated that various modifications and changes can be made to the above described embodiments of a compressor assembly as disclosed herein without departing from the scope of the following claims.