BACKGROUND OF THE INVENTION
[0001] The present invention relates to a package-type fluidic apparatus in which a fluid
machine such as a scroll compressor, a vacuum pump, an expander or a blower is connected
to a drive source.
[0002] To reduce noise from a compressor and a drive source for driving it, they are often
disposed within a package. A single high-output compressor is included within the
package, or a plurality of low-output compressors are piled up to form a high-output
compressor in a package.
[0003] In particular, when a compressor is used in a factory, in view of the maximum air
consumption, a single high-output compressor for producing it is used within a package.
[0004] However, when air produced by a high-output compressor is used in a factory, the
rate of operation is about 100 % all day long, while it decreases to less than 50
% depending on time in a day. According to a season in a year, compressed air consumption
is variable and power source for driving a compressor cannot frequently be switched
on and off when a high-output compressor is used.
[0005] In a medium-sized or large machine in which a large air tank is difficult to put,
as frequency of starting and stopping increases, it becomes likely to generate heat
during starting of a motor, to decrease life of an electromagnetic switch and to cause
mechanical problem of a compressor, and a motor starting current of a compressor becomes
five to six times as that of rated operation to involve decrease in power source.
In a large machine, voltage of power source decreases owing to the starting current
and adverse effects to transforming and distribution installation so as not to enable
on/off of the power source frequently.
[0006] To solve such problems, for example, when output of the compressor is 15 kW, four
compressors having output of 3.7 kW are included in a package. The compressors start
with staggered time and the first, second, third and fourth compressors start in order
to avoid the problem.
[0007] Depending on air consumption, it is possible to determine the optimum number of operation.
Specifically, a plurality of compressors such as four are piled up to constitute a
single package compressor. When it operates with about 100 % of compression air, all
the four compressors operate. One of the four stops with about 70 % of air consumption;
two stop with less than 50 %; three stop with further decrease; and all stop with
further decrease.
[0008] Thus, electric power consumption is corresponding to the compression air consumption.
Electric power consumption decreases compared with a single high-output compressor.
If the compressor stops owing to any cause, capability for producing compression air
becomes null immediately in the single high-output compressor to result in stop of
all machines in which compression air is used, thereby increasing damage in the factory.
[0009] On the contrary, in a plurality of compressors, even if one stops, it will avoid
the risk that operation completely stops, as the others continue to operate. A plurality
of compressors may preferably be employed.
[0010] In a plurality of compressors, a compressor and its drive source form a set of subsidiary
unit. However, when a plurality of the subsidiary units are disposed horizontally
or stepwise, a required area increases to unable its location. To decrease the area,
a plurality of subsidiary units are vertically piled.
[0011] It is possible to pile them up, but is limited by height of a room and by how to
transport. For maintenance of the taller compressor, a ladder must be used thereby
increasing work of maintenance and involving danger.
SUMMARY OF THE INVENTION
[0012] In view of the disadvantages, it is an object of the invention to provide a package-type
fluidic apparatus that can be maintained without ladders or without increase in area
thereby facilitating inspection and maintenance of the fluid machine, for example,
in case of a scroll compressor, enabling a fixed scroll to be disassembled, tip seals
of fixed and orbiting scrolls to be replaced, a bearing to be greased up and a subsidiary
unit to be exchanged easily.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] The above and other features and advantages of the invention will become more apparent
from the following description with respect to an embodiment as shown in appended
drawings wherein:
Fig. 1 is a front perspective view of a best-mode embodiment of a package-type fluidic
apparatus according to the present invention;
Fig. 2 is a front elevational view of Fig. 1, removing right and left front closing
plates of a housing, electric wires to a motor and conduits to the fluid machine;
Fig. 3 is a front upper perspective view of Fig. 1, removing a top plate, the closing
plates and an inspection door;
Fig. 4 is a top plan view in which the top plate is removed; and
Fig. 5 is a vertical sectional view taken along the line V-V in Fig. 2.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENT
[0014] Two housings 2,2 each of which has four chambers 1 piled up are disposed with a space
which is a sucking path 3. The housings 2,2 have the same shape and size, and the
four chambers 1 have the same shape and size.
[0015] The sucking path 3 is closed by a removable inspection door 5 between front walls
4,4 over the housings 2,2. The upper part of the sucking path 3 is closed by an operation-display
plate 5b. The rear end of the sucking path 3 opens, and external air is taken in through
the rear opening.
[0016] The side ends of the operation-display plate 5b are mounted with screws to the opposing
ends of the housings 2,2, and the operation-display plate 5b can be removed, if required.
The inspection door 5 is removable by pushing down a slide latch 5a with a finger
to open, so that sucking filters of fluid machines 8 in the housings 2,2 are inspected
for maintenance.
[0017] On a bottom plate 6 of each of the chambers 1, a motor 7 and the fluid machine 8
such as a compressor or a decompression device behind the motor 7 are connected to
pulleys 9,10 and a belt 11 to form a fluid machine unit 12.
[0018] In the chamber 1 of each of the housings 2,2, a sucking hole 14 is formed through
the inner side wall 13 to allow each of the housings 2,2 to communicate with the sucking
path 3. In the chamber 1 of each of the housings 2,2, an exhaust hole 16 is formed
in a rear wall 15. A tall exhaust duct 17 is provided along the four exhaust holes
16 vertically arranged behind the housing 2. An electric exhaust fan 18 is provided
in the top wall of the exhaust duct 17.
[0019] By driving the exhaust fans 18,18 and actuating the fluid machine units 12 positioned
depending on gas volume to be pressurized or depressurized, a place where the gas
is utilized and reaching time to a predetermined pressure, external air flows into
the chamber 1 through the sucking path 3 and the sucking opening 14 and moves rearward.
The air is discharged from the exhaust fan 18 through the exhaust duct 17.
[0020] Thus, the motor 7 and fluid machine 8 in the chamber 1 are cooled with external air,
thereby avoiding overheat generated with continuous long-time operation and preventing
damage to sliding parts.
[0021] The motor 7 and fluid machine 8 in the chamber 1 can be inspected and maintained
by removing a closing plate at the rear end of the sucking path 3 and then removing
the inner side wall 13 facing the sucking path.
[0022] The foregoing merely relates to an embodiment of the invention. Various changes and
modifications may be made by a person skilled in the art without departing from the
scope of claims wherein:
1. A package-type fluidic apparatus comprising:
two housings each comprising a chamber that has a fluid-machine unit in which a fluid
machine is connected to a drive source;
a sucking path between the two housings;
a sucking hole formed in an inner side wall of each of the housings to allow each
of the housings to communicate with the sucking path; and
an exhaust duct at a rear wall of each of the housings, said exhaust duct having an
exhaust fan.
2. A package-type fluidic apparatus as claimed in claim 1 wherein the two housings have
substantially the same shape and size.
3. A package-type fluidic apparatus as claimed in claim 1 wherein a plurality of chambers
are piled up in each of the housings, the exhaust duct being connected to rear walls
of said plurality of chambers.
4. A package-type fluidic apparatus as claimed in claim 1 wherein the sucking path opens
at a rear end between the housings.
5. A package-type fluidic apparatus as claimed in claim 1 wherein a front end of the
sucking path is closed by an operation display plate and a removable inspection door
between the housings.