PNEUMATIC DRIVE, JET ENGINE (VARIANTS) AND ELECTROPNEUMATIC CONTROL DEVICE

Abstract

 The invention can be used for remote control of a valve system of gas, oil and product pipelines. The inventive pneumatic drive comprises an electropneumatic control device provided with electromagnets, pneumatic distributors and gasflow-control units connected to input pipes of a jet engine. The rotor of said engine is provided with axial channels connected to nozzles, the shaft thereof being connected to a reducing gear by means of a gear rim. The reducing gear comprises a hand-worked doubler provided with a mechanism for automatically braking a handwheel. A gear is mounted on a shaft provided with a lead screw of a crank screw rotation gear. The inventive drive also comprises a unit absorbing kynetic energy of movable parts thereof provided with disk springs. The rotation gear comprises a sliding nut provided with two trunnions arranged in the grooves of a crank which is connected to an output shaft of the drive and to a controlled object. The shaft is connected to an input spindle of the device. Reed switches provided with constant magnets are arranged inside the spindle.

Description

Technical Field

[0001] The invention is related to pneumatic mechanical engineering particularly to the mechanisms intended for rearranging, monitoring and programmable control of control elements of a valve system of gas, oil and product pipelines and control devices while effecting remote and local control thereof.

Background Art

[0002] A pneumohydraulic drive with the piston engine containing pneumatic cylinders, pistons, rotation gear, limit switches (See e.g. Gurevich A. F. and others., "Gas and Oil Pipelines Devices Guidebook" Leningrad, "Nedra", 1988. p. 346) is known.

[0003] The engineering deficiencies of this drive include: presence of moving rubbing seals which reduces drive reliability and service life, large volume of the pressurized air filled cavities, which results in impact actions on the controlled object, probability of the arbitrary movement of the drive output shaft under the external load.

[0004] A pneumohydraulic drive with the piston engine containing pneumohydraulic cylinder, pistons, crank rotation gear, limit switches (See e.g. Gurevich A. F. and others., "Gas and Oil Pipelines Devices Guidebook" Leningrad, "Nedra", 1988. p. 348) is known.

[0005] The engineering deficiencies of this drive include: presence of oil or special fluid as the second actuating medium, which makes the drive operation more complicated and expensive; presence of the rubbing moving seals; probability of the arbitrary movement under external loads.

[0006] A pneumatic drive with jet engine which contains electropneumatic control device, pneumatic jet engine, reducing gear, hand-operated doubler, rotation gear, maximum transmitted moment restrain arrangement is known (RU 2131065 C1, F 15 B 9/03 27.05.1999).

[0007] The rotation gear comprises the crank screw gear consisting of the grooved crank rigidly fixed to the drive output shaft, the lead screw mounted inside the housing, the sliding nut flexibly connected to the screw whereat the nut is fixed to the guide and the two sides of the guide are equipped with two coaxial trunnions with two sliders on each trunnion.

[0008] The rotation gear housing is made of two parts namely the housing proper and the cover where each part is furnished with a lead groove whereas the grooves are parallel to each other and the outer guide sliders flexibly fits respectively into one and the other grooves and the middle sliders fits respectively into one and the other grooves of a crank (RU 2131065 C1, F 15 B 9/03 27.05.1999).

[0009] The engineering deficiencies of this design include its complexity and large size due to the presence of two reference grooves in different housing components, four sliders and long trunnions.

[0010] Other deficiencies of the said design include the presence of the maximum transmitted moment restrain arrangement which complicates the drive design considerably, reduces its reliability and makes its operation more complicated.

[0011] A jet engine is known, which comprises the housing, input pipes, rotor with a shaft equipped with gear rim and axial channels connected to the input pipes and connected to the respective nozzles located on the opposite rotor arms by means of radial channels made in the rotor arms crank (RU 2131065 C1, F 15 B 9/03 27.05.1999).

[0012] The engineering deficiencies of the said engine include the complex realization of the design and engine rotor balancing.

[0013] An electropneumatic control device is known which comprises explosion-proof chamber, electromagnets, pneumatic distributors connected via pushers to electromagnets, limit switches connected to the output roller crank (RU 2131065 C1, F 15 B 9/03 27.05.1999).

[0014] The engineering deficiencies of this device include: design complexity, large dead band of the limit switches when open caused by a large hysteresis value of reed switches.

Disclosure of the Invention

[0015] The engineering objective of the invention is to create a pneumatic drive for valve system of gas and oil pipelines and control devices which is to feature a simplified design, to have enhanced reliability, service life and efficiency, to be applicable for operations within a wide range of pipeline gas pressure from 1.0 MPa up to 16 MPa, to have enhanced power and torque control range, an option to adjust the output shaft rotation period between its positions, improved limit switches operation accuracy and enhanced performance.

[0016] This engineering objective is achieved due to the fact that rotation gear housing is made as a central body with two covers whereat the housing is furnished with a rectangular section through reference groove which accommodates the guide with a sliding nut threaded to the lead screw attached to the unit absorbing kinetic energy of drive movable parts, whereat the drive is equipped with the drive latching arrangement.

[0017] That engineering objective is also realized owing to the fact that the jet engine is made with replacement nozzles assemblies, electropneumatic control device is made as a single assembly while the device input roller passes through the explosion-proof chamber casing and cover and the moving constant magnets are linked to the input roller via mechanical overgear and located outside the explosion-proof chamber while the electropneumatic control device is equipped with gasflow-control units with inlets thereof being connected respectively to the gasflow-control units outlets and outlets being connected to the jet engine input pipes while the pneumatic distributor is furnished with a separate channel with its inlet connected to the compressed gas source and the outlet connected to the pneumatic distributor servovalve inlet.

[0018] The nature of the invention is that the rotation gear housing of the pneumatic drive is made as a central body with two covers. The pneumatic drive comprises sequentially connected electropneumatic control device consisting of electromagnets, pneumatic distributors connected to the pressurized actuating medium source, reversing jet engine with the shaft thereof being linked through the mechanical reducing gear to crank screw rotation gear and drive output shaft, hand-operated doubler, and limit switches. The rotation gear housing is made as a central body with two covers wherewith the housing is furnished with a rectangular section through reference groove which accommodates the guide with a sliding nut, whereat the two sides of the guide are equipped with short trunnions with one slider on each that are flexibly fitted into in the crank grooves as appropriate.

[0019] The nature of the invention is also that the lead screw of the crank screw rotation gear is attached to the unit absorbing kinetic energy of drive movable parts which is made as a package of disc springs and connected to the axially moveable lead screw.

[0020] The nature of the invention is also that the drive is equipped with the drive latching arrangement comprising the pneumatic cylinder accommodated in the cylinder, the spring-loaded piston with its stick flexibly connected to one of the reducing gear recessed gears while the pneumatic cylinder is connected to the pneumatic distributors outlets by air lines.

[0021] The nature of the invention is also that the jet engine comprising the housing, shaft-attached rotor with its nozzles connected via radial and axial channels to the input pipes, has the rotor with through holes on the arms end thereof. These holes are normal to the rotor rotation axis and to its longitudinal axis of symmetry and accommodate the nozzles assemblies implemented as cylinders and inner holes in the shape of the oppositely directed Laval nozzles separated by the blank bulkhead where the inlet part of each nozzle has a side channel connected to the respective channel of the rotor arm.

[0022] The nature of the invention is also that another jet engine variant comprising housing, shaft-attached rotor equipped with the nozzles connected through radial and axial channels to the input pipes whereat the rotor is made as a central bushing rigidly fixed to two arms with the unidirectional nozzles thereof while each nozzle is respectively connected to one of the input pipes.

[0023] The nature of the invention is also that electropneumatic control device comprising the electromagnets, limit switches, pneumatic distributors with the inlets thereof connected to the pressurized actuating medium source and the outlets connected to the jet engine input pipes while the input roller of the device passes through the explosion-proof chamber casing and cover and moving constant magnets are connected to the input roller through the mechanical overgear and located outside the explosion-proof chamber.

[0024] The nature of the invention is also that the electropneumatic device is equipped with the gasflow-control units with the inlets thereof connected to the pneumatic distributors outlets as appropriate and the outlets are connected to the jet engine input pipe.

[0025] The nature of the invention is also that the pneumatic distributor is furnished with a separate channel with the inlet thereof connected to the compressed gas source and the outlet - to the pneumatic distributor servovalve inlet.

[0026] The casual relation between the achieved engineering result and the combination of features. The enhanced reliability and service, and simplified design of the drive are achieved:

1. Owing to the fact that the rotating gear housing is made as a central body with two covers whereat the housing is furnished with a rectangular section through reference groove which accommodates the guide with the sliding nut which is threaded onto the lead screw whereat the two sides of the guide have short trunnions with one slider on each, which are flexibly fitted into the crank grooves as appropriate.

2. Owing to the fact that the lead screw of the crank screw rotation gear is connected to the unit absorbing kinetic energy of drive movable parts, which is made as a package of disc springs and connected to the axially movable lead screw.
   That permits to ensure the conditions when under any drive operation mode the maximum possible moment at the output shaft shall never exceed the rated permissible value.

3. Owing to the fact that the rotor arms tips are furnished with through holes normal to the rotor rotation axis and to its longitudinal axis of symmetry and which accommodate the nozzles assemblies implemented as cylinders and inner holes in the shape of the oppositely directed Laval nozzles separated by the blank bulkhead where the inlet part of each nozzle has a side channel connected to an appropriate rotor arm channel.

4. Owing to the implementation of a separate channel in the pneumatic distributor with the inlet thereof connected to the pressurized actuating medium source and its outlet connected to the inlet of the pneumatic distributor servovalve. The extended actuating medium pressure range and the enhanced drive power and torque control range are achieved by mean of equipping the drive (electropneumatic control device) with gasflow-control units.

[0027] The improved efficiency of the drive is achieved by equipping the drive with gasflow-control units and the drive latching arrangement; the latter permits to use in the drive a highly efficient non-self-reversible screw gear and to reduce the required gasflow when the device control element is readjusted (15-40)%.

[0028] The advanced performance of the drive is achieved due to elimination of the second actuating medium and simplifying the limit switches adjustment procedure.

[0029] Improved accuracy of the limit switches operations is achieved due to the fact that the moving constant magnets are connected to the input roller via the mechanical overgear and are located inside the explosion-proof chamber.

Brief Drawings Description

[0030] The following example of the invention realization with the referenced drawings shall explain the invention where:
   Fig. 1 shows the pneumatic drive diagram, Fig 2 shows the A-A section view of the jet engine rotor, Fig 3 shows the side view of the jet engine rotor with four nozzles and replacement nozzles assembly, Fig 4 shows the section view of the jet engine rotor implemented as the central bushing connected to two arms and to the unidirectional nozzles, Fig 6 shows the top view of the crank screw rotation gear, Fig 7 shows the A-A section view of the rotation gear as of Fig 6, Fig. 8 shows the section view of the electropneumatic control device crank gear, Fig 9 shows the A arrow view of the Fig. 8, Fig 10 shows the section view of the electropneumatic control device pneumatic distributor, Fig 11 shows the drive latching arrangement diagram.

The Best Mode for Carrying Out the Invention

[0031] Pneumatic drive (Fig. 1) contains sequentially connected electropneumatic control device 1, comprising electromagnets 2, 3, pneumatic distributors 4,5, the inlet thereof being connected to the pressurized actuating medium source (not shown) and the outlets being connected via the channels to the gasflow-control units 6, 7 inlets, the outlets of which are connected to the input pipes 8, 9 of the reversing jet engine 10, the rotor 11 of which (Fig 2-5) contains axial channels 13, 14, connected via the tilted and radial channels to nozzles 15, 16, 17, 18, while shaft 19 of rotor 11 is connected by means of gear rim 20 to mechanical reducing gear 21 which contains hand-operated doubler 22 with the mechanism 23 for automatically braking a handweel 24 . A gear 26 of the reducing gear is mounted with limited angle rotation on the shaft connected to lead screw 27 via crank screw rotation gear 28 whereat the end of lead screw 27 is attached to the unit absorbing kinetic energy of drive movable parts 28 implemented as a package of disc springs 30 and mounted on the tip of lead screw 27 where the controlled precompression thereof is possible.

[0032] Rotation gear (Fig. 6, 7) also contains guide 31 with sliding nut 32 equipped with two trunnions 33, 34 which by means of sliders 35, 36 are fitted onto the crank 37 grooves with the crank being rigidly fixed to the drive output shaft 38 and further on to controlled object 39.

[0033] Output shaft 38 of the drive is attached to input roller 41 of electropneumatic device 1 (Fig. 8, 9) passing through cover 42 of explosion-proof chamber 43 where reed switches 44, 43 are accommodated. Roller 41 is connected with dual arm 46 with adjustment screws 47, 48, while spring-loaded rods 51, 51 with constant magnets 52, 53 affixed thereto are flexibly attached to axis 49 rigidly mounted inside the housing.

[0034] Rotor 11 of jet engine 10 (Fig. 2, 3) contains nozzle assemblies 55, 56 with nozzles 15, 16, 17, 18 made therein and installed into the rotor 11 arms.

[0035] In the other variant (Fig. 4, 5) rotor 11 of jet engine 10 contains central bushing 57 and arms 58, 59 attached thereto with unidirectional nozzles 15.

[0036] Pneumatic distributor 4, 5 (Fig. 10) contains housing 51, 5 servovalve 62, piston 63, valve 64, filter 65, rod 66, inlet channel 67, outlet channel 68, and inlet channel 69 of the servovalve.

[0037] Fig. 1 and 10 also show the input pressure P_in, output pressure P_out. and input pressure P_in1 in the servovalve input channel.

[0038] The drive pneumoelectric latching arrangement contains pneumatic cylinder 71, piston 72 with stick 73 loaded with spring 74 and linked to handle 75. The tapered tip of stick 73 fits into recess 76 made on one of the movable parts e.g. on gear 77 connected via gear 78 to shaft 19 of jet engine 10.

[0039] The joint operations of pneumatic drive, jet engine and electropneumatic control device are as follows.

[0040] When the electropneumatic control device 1 receives a control signal to rotate the drive output shaft 38 e.g. to electromagnet 2, the latter is actuated and its pusher turns shaft 66 which results in servovalve 62 operation, movement of piston 63 and valve 64 and opening the gas passage from input channel 63 with the pressure P_in into output channel 68 and further to input pipe 9 of jet engine 10 and the gas is further supplied along axial channel 14 to coupled nozzles, e.g. 15, 17 and when released there them it creates reactive force and driving torque on shaft 19 of rotor 11.

[0041] In another variant (Fig. 4, 5) the gas is released from one nozzle 15 via axial channel 57 and the channel in one of the rotor 11 arms, e.g. 58 and creates driving torque on shaft 19 of rotor 11.

[0042] The driving torque of rotor 11 shall be transferred via gear rim 20 and further on through reducing gear 21 to gear 26 and further via splined gear to lead screw 27.

[0043] When lead screw 27 rotates then sliding nut 32 threaded thereto with guide 31 moves along lead screw 27 and turns crank 37 together with the drive output shaft 38 and further the control element of controlled object 39 concurrently rotating electropneumatic control device 1 input roller 41 linked to output shaft 28 together with the dual rod 46 attached to roller 41 with adjustment screws 47, 48. While approaching its extreme position the dual rod presses the short end of one of the rods (depending on the movement direction), e.g. 51, whereat rod 51 rotates and moves constant magnet 53 attached thereto towards the reed switch 44, which results in reed switch 44 breaking thus breaking electromagnet 2 circuit whereat pneumatic distributor 4 operates and blocks the feeding gas supply to jet engine 10 but rotor 11 of jet engine 10 and other drive movable parts continue their movement powered by the kinetic energy accumulated during their movement. When crank 37 fits into the mechanical limit stop (not shown), then crank 37, output shaft 38, guide 31, sliding nut 32 are stopped while lead screw 27 continues its rotation and threads into nut 32 moving along its axis e.g. rightwards, and via the bearing compresses spring 30 which absorbs therewith the drive movable parts kinetic energy.

[0044] In order to reverse the drive output shaft 38 the control voltage is fed to electromagnet 3, which opens pneumatic distributor 5 whereat the actuating medium is admitted from its source into gasflow-control unit 7 and further to input pipe 8 of jet engine 10 whereat rotor 11 rotates in the opposite direction; when shaft 38 reaches its extreme position the contacts of appropriate limit switch 45 are broken, the actuating medium supply to engine 10 is cut off and the drive is stopped.

[0045] When the drive is equipped with the drive latching arrangement then concurrently with its admission to jet engine 10 the actuating medium is admitted into pneumatic cylinder 71 of latching arrangement and moves stick 73 out of recess 76 located on one of reducing gear 21 movable parts thus enabling rotation of rotor 11 of jet engine 10.

Industrial Applicability

[0046] Theoretical calculations and vast extent of the experimental analysis and testing of several drive standard sizes and modifications conducted at the experimental test ranges and field performance programs in different regions of Russia within the period of 1987-2000 justify competence and efficiency of the suggested structural, circuit and parametric solution.

Claims

1. The pneumatic drive comprising sequentially connected electropneumatic control device consisting of electromagnets, pneumatic distributors connected to the pressurized actuating medium source, reversing jet engine with the shaft thereof being linked through the mechanical reducing gear to crank screw rotation gear and drive output shaft, hand-operated doubler, limit switches, wherein the rotation gear housing is made as a central body with two covers where the housing is furnished with a rectangular section through reference groove which accommodates the guide with a sliding nut, whereat the two sides of the guide are equipped with trunnions with one slider on each that are flexibly fitted onto the crank grooves as appropriate.

2. The pneumatic drive as per paragraph 1 wherein the lead screw of the crank screw rotation gear is connected to the unit absorbing kinetic energy of drive movable parts that is implemented as a package of disc springs and connected to the axially movable lead screw.

3. The pneumatic drive as per paragraph 1 wherein the said drive is equipped with the drive latching arrangement comprising the pneumatic cylinder accommodated in the cylinder, the spring-loaded piston with the stick flexibly attached to one of the reducing gear recessed gears, the pneumatic cylinder is connected to the pneumatic distributors outlets by air lines.

4. The jet engine comprising the housing, the rotor fixed to the shaft, with the nozzles connected via radial and axial channels to the input pipes, wherein the rotor arms tips are furnished with through holes, which are normal to the rotor rotation axis and to its longitudinal axis of symmetry and accommodate the nozzles assemblies implemented as cylinders and inner holes in the shape of the oppositely directed Laval nozzles separated by the blank bulkhead where each nozzle has a side channel connected to the respective rotor arm channel.

5. The jet engine comprising the housing, shaft-attached rotor, equipped with the nozzles connected through radial and axial channels to the input pipes wherein the rotor is made as a central bushing rigidly fixed to two arms with the unidirectional nozzles thereof while each nozzle is respectively connected to one of the input pipes.

6. The electropneumatic control device comprising the electromagnets, limit switches, pneumatic distributors with the inlets thereof being connected to the pressurized actuating medium source and the outlets connected to the jet engine input pipes wherein the input roller of the device passes through the explosion-proof chamber casing and cover, and moving constant magnets are connected to the input roller through the mechanical overgear and are located outside the explosion-proof chamber.

7. The electropneumatic control device as per paragraph 6 wherein it is equipped with the gasflow-control units with the inlets thereof being connected to the pneumatic distributors outlets as appropriate and the outlets being connected to the jet engine input pipes.

8. Electropneumatic control device as per paragraph 6 wherein the pneumatic distributor is furnished with a separate channel the inlet thereof being connected to the compressed gas source and the outlet thereof being connected to the inlet of the pneumatic distributor servovalve.

Drawing