Double-buffered actuating device for a compressor stepless air volume regulating valve

Abstract

The application discloses a driving double-buffering execution device of a stepless air volume adjusting air valve of a compressor. The application comprises an execution mechanism main body, an oil inlet joint connected to the upper part of the execution mechanism main body, a two-position three-way high-speed electromagnetic valve connected to the middle part of the execution mechanism main body, a plunger assembly connected to the lower part of the execution mechanism main body, and an oil return joint connected to the left part of the execution mechanism main body. An air valve opening buffer assembly is arranged in the oil inlet joint. The application provides a set of buffer devices which are completely independent in the valve opening and closing process and are fast at first and slow at last, so that the opening and closing process of the valve is independently controllable, the fast movement section and the buffer section of the plunger can be well matched with the movement process of the compressor pressure valve, and thus the control precision of the air supply volume and the output pressure of the compressor is improved.

Description

Technical Field

[0001] This invention relates to the field of compressor technology, and in particular to a double-buffered actuator for driving a compressor stepless air volume regulating valve. Background Technology

[0002] In order to save energy, more and more large reciprocating piston compressors are adopting electronically controlled gas distribution systems. The electronic controller controls the opening and closing time of the intake valve according to the required gas supply downstream, so that the compressor is transformed from the original fixed displacement gas supply mode to a variable displacement gas supply mode, realizing stepless adjustment of the gas supply.

[0003] The compressor intake valve is controlled by a two-position three-way valve that controls a hydraulic piston actuator, which in turn drives the valve plate to reciprocate via an unloader. Due to the high-speed response of the hydraulic system, without buffering measures, the valve plate will rapidly impact the valve seat under hydraulic or pneumatic pressure during the opening and closing process. This enormous impact will quickly damage the valve plate and affect the service life of the intake valve.

[0004] To address the aforementioned issues, current technology employs a buffering technique where the valve closes quickly and then slows down. However, during the valve opening process, a fixed throttle nozzle is used to limit the speed of the entire opening process. While this provides a buffering effect, the slow valve opening action can affect the control accuracy of the compressor's gas supply volume and pressure.

[0005] Although the double-buffering technology is used in Chinese patent CN 110778490 A, it still has problems. In this technology, after the air valve is closed and seated, in order to ensure complete contact between the valve plate and the valve seat, the piston in the unloader and actuator must move upward for a certain distance to completely disengage the unloader from the valve plate. This results in a gap between the valve plate and the unloader when the air valve is in the closed position. Therefore, in this technology, during the process of the actuator piston pushing the unloader to open the air valve, the idle stroke between the unloader and the valve plate (the gap between the valve plate and the unloader) must be completed before the air valve can be opened. Furthermore, in this technology, the two buffering processes for the valve opening and closing are coupled together, meaning that the rapid segment of piston movement is equal in both processes. During the design process, the buffering requirements of the valve closing process are generally given priority. However, during the valve opening process, due to the gap between the valve plate and the unloader, a rapid section is used up when the valve plate just comes into contact with the valve plate. As a result, the rapid section has a short stroke and most of the stroke is in the buffer section when the valve plate is actually opened. In other words, the valve plate opening speed is mostly in a buffered state, which will affect the system control accuracy of the compressor's air supply and air supply pressure. Summary of the Invention

[0006] The purpose of this invention is to provide a dual-buffered actuator for driving a compressor's stepless air volume regulating valve. This invention provides a set of buffer devices with completely independent, fast-then-slow valve opening and closing processes, making the valve's opening and closing processes independently controllable. The rapid movement segment of the plunger and the buffer segment can be well matched with the movement process of the compressor's pressure valve, thereby improving the control accuracy of the compressor's air supply and output pressure.

[0007] The technical solution of the present invention: A dual-drive buffer actuator for a compressor stepless air volume regulating valve includes an actuator body, an oil inlet connector connected to the upper part of the actuator body, a two-position three-way high-speed solenoid valve connected to the middle part, a plunger assembly connected to the lower part, and an oil return connector connected to the left part; the oil inlet connector is provided with a valve opening buffer assembly; the two-position three-way high-speed solenoid valve is provided with a valve closing buffer assembly.

[0008] In the aforementioned compressor stepless air volume regulating valve drive double buffer actuator, the air valve opening buffer assembly includes a baffle located at the lower part of the oil inlet connector, a guide bushing in the middle, an air valve opening buffer piston in the guide bushing, a throttling orifice on the air valve opening buffer piston, and a air valve opening buffer piston return spring between the air valve opening buffer piston and the baffle; a plug is located at the upper part of the guide bushing, and a filter screen is located between the plug and the guide bushing.

[0009] In the aforementioned compressor stepless gas volume regulating valve drive double buffer actuator, an oil inlet locking plate is sleeved on the oil inlet connector; an oil outlet locking plate is sleeved on the oil return connector; the oil inlet locking plate and the oil outlet locking plate are respectively connected to the actuator body by fastening screws.

[0010] In the aforementioned compressor stepless air volume regulating valve drive double buffer actuator, the two-position three-way high-speed solenoid valve includes a valve body, the left part of which is connected to the oil return port connector, the middle part of which is provided with a valve core, the upper middle part of which is provided with a one-way valve, and the right part of which is connected to an electromagnet assembly; the right part of the valve core is provided with a spring; and the left part of the valve core and the oil return port connector are provided with an air valve closing buffer assembly.

[0011] In the aforementioned compressor stepless air volume regulating valve drive double buffer actuator, the air valve closing buffer assembly includes an air valve closing buffer piston sleeved on the left side of the valve core, an air valve closing buffer piston return spring sleeved on the air valve closing buffer piston, and a return oil valve seat on the left side of the air valve closing buffer piston return spring.

[0012] In the aforementioned compressor stepless gas volume regulating valve drive double buffer actuator, the valve closing buffer piston is provided with two symmetrically arranged throttling orifices.

[0013] In the aforementioned dual-buffered actuator for driving the stepless gas volume regulating valve of the compressor, the inner hole of the valve seat and the left end of the valve core of the return oil valve are both set with conical surfaces; the diameter of the inner hole of the valve seat is equal to the diameter of the valve core guide hole where the valve core is located.

[0014] In the aforementioned dual-buffered actuator for driving the stepless gas volume regulating valve of the compressor, the oil return valve seat and the left end of the valve core form the oil return valve port; the middle part of the valve core and the valve body form the oil inlet valve port; and the lower part of the valve body and the upper end of the plunger assembly form the control port.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] 1. The opening and closing processes of the compressor intake valve of the present invention can be controlled, and the process of fast-then-slow can be independently controlled. This allows the fast and buffer sections of the piston movement to be well matched with the valve mechanism, solving the impact problem when the valve body sits down, and improving the precise control of the compressor air volume.

[0017] 2. Compared with the existing mechanism, the inner diameter of the valve-closing buffer piston of this invention is increased and the cross-sectional area of ​​the buffer piston is reduced. In order to ensure that the stroke of the plunger in the fast section remains unchanged, the stroke of the buffer piston must be increased, which can improve the control accuracy of the transition point from the fast section to the buffer section.

[0018] 3. In this invention, the buffer throttling orifice of the valve closing buffer piston is changed from one in the existing mechanism to two symmetrical ones. In this way, the jet force of the buffer piston passing through the two throttling orifices is balanced during the valve closing process, which improves the stability of the valve closing buffer piston falling to the return valve seat and thus improves the accuracy of the valve closing process.

[0019] 4. The sealing structure of the return oil valve of this invention is changed from the current valve core outer circle sealing (the angle formed by the outer circle of the valve core and the conical surface of the valve core forms a seal with the conical surface of the valve seat) to valve seat hole sealing (the angle formed by the inner hole of the valve seat and the conical surface of the valve core forms a seal with the conical surface of the valve core, and the conical angle of the valve seat is slightly larger than the conical angle of the valve core), and it ensures that the diameter of the inner hole of the valve seat is equal to the diameter of the guide hole of the valve core (i.e., Figure 11 The formula d2 = d1) improves the sealing ability to resist the backflow force of the compressor valve, which pushes the valve and then transmits it to the plunger, increasing the pressure in the plunger cavity.

[0020] 5. The present invention adds locking gaskets at the oil inlet and oil outlet joints to prevent the two joints from loosening during operation, making the internal connection structure more reliable and improving the stability of the double buffer. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the structure of the present invention;

[0022] Figure 2 This is a schematic diagram of the internal structure of the present invention;

[0023] Figure 3 This is a schematic diagram of the structure of the air valve opening buffer assembly and the oil inlet connector;

[0024] Figure 4 This is a schematic diagram of a two-position three-way high-speed solenoid valve;

[0025] Figure 5 This is a schematic diagram of a one-way valve;

[0026] Figure 6 This is a schematic diagram of the structure of the air valve closing buffer piston;

[0027] Figure 7 This is a cross-sectional view of the air valve closing buffer piston.

[0028] Figure 8 This is a schematic diagram of the oil inlet locking plate;

[0029] Figure 9 This is a schematic diagram of the oil outlet locking plate;

[0030] Figure 10 This is a schematic diagram of the air valve opening buffer assembly;

[0031] Figure 11 This is a schematic diagram of the air valve closing buffer assembly.

[0032] The labels in the attached diagram are as follows: 1-Actuator body, 2-Inlet connector, 3-Two-position three-way high-speed solenoid valve, 4-Plunger assembly, 5-Return port connector, 6-Air valve opening buffer assembly, 7-Baffle, 8-Guide bushing, 9-Air valve opening buffer piston, 10-Air valve opening buffer piston return spring, 11-Throttle orifice one, 12-Plug, 13-Filter screen, 14-Inlet locking plate, 15-Outlet locking plate, 16-Fasting screw, 17-Valve body, 18-Valve core, 19-Electromagnet assembly, 20-Check valve, 21-Spring, 22-Air valve closing buffer assembly, 23-Air valve closing buffer piston, 24-Air valve closing buffer piston return spring, 25-Return valve seat, 26-Throttle orifice two, 27-Return valve port, 28-Inlet valve port, 29-Control port, 30-Inlet. 31-Oil return port, 32-One-way valve seat, 33-One-way valve spring, 34-Copper pad, 35-Valve seat inner hole, 36-Valve core guide hole. Detailed Implementation

[0033] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0034] In the description of this invention, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0035] Example. A dual-buffered actuator for driving a compressor stepless air volume regulating valve, configured as follows: Figure 1-11 As shown, it includes an actuator body 1, with an oil inlet connector 2 connected to the upper part of the actuator body 1, a two-position three-way high-speed solenoid valve 3 connected to the middle part, a plunger assembly 4 connected to the lower part, and an oil return connector 5 connected to the left part; the oil inlet connector 2 is provided with a valve opening buffer assembly 6; the two-position three-way high-speed solenoid valve 3 is provided with a valve closing buffer assembly 22.

[0036] The valve opening buffer assembly 6 includes a baffle 7 located at the lower part of the oil inlet connector 2, a guide bushing 8 in the middle, a valve opening buffer piston 9 located in the guide bushing 8, a throttle orifice 11 located on the valve opening buffer piston 9, and a valve opening buffer piston return spring 10 located between the valve opening buffer piston 9 and the baffle 7; a plug 12 is located at the upper part of the guide bushing 8, and a filter screen 13 is located between the plug 12 and the guide bushing 8.

[0037] An oil inlet locking plate 14 is fitted onto the oil inlet connector 2; an oil outlet locking plate 15 is fitted onto the oil return connector 5; the oil inlet locking plate 14 and the oil outlet locking plate 15 are respectively connected to the actuator body 1 by fastening screws 16.

[0038] The two-position three-way high-speed solenoid valve 2 includes a valve body 17, with the left part of the valve body 17 connected to the oil return port connector 5, the middle part provided with a valve core 18, the upper middle part provided with a one-way valve 20, and the right part connected to an electromagnet assembly 19; the right part of the valve core 18 is fitted with a spring 21; and the left part of the valve core 18 and the oil return port connector 5 are provided with a pneumatic valve closing buffer assembly 22.

[0039] The valve closing buffer assembly 22 includes a valve closing buffer piston 23 sleeved on the left side of the valve core 18, a valve closing buffer piston return spring 24 sleeved on the valve closing buffer piston 23, and a return oil valve seat 25 provided on the left side of the valve closing buffer piston return spring 24.

[0040] The gas valve closing buffer piston 23 is provided with two symmetrically arranged throttling orifices 26.

[0041] The right end of the valve seat inner hole 35 of the return valve seat 25 and the left end of the valve core 18 are both tapered surfaces; the tapered angle on the return valve seat 25 is slightly larger than the tapered angle on the valve core 18, and the diameter d2 of the valve seat inner hole 35 is equal to the diameter d1 of the valve core guide hole 36 where the valve core 18 is located (this diameter is also the diameter of the right half of the valve core 18).

[0042] The return valve seat 25 and the left end of the valve core 18 form the return valve port 27; the middle part of the valve core 18 and the valve body 17 form the inlet valve port 28; the lower part of the valve body 17 and the upper end of the plunger assembly 4 form the control port 29.

[0043] The inlet passage consists of an oil inlet 30, an air valve opening buffer assembly 6, a one-way valve 20, and an oil inlet valve port 28; the return passage consists of an oil return port 31, an air valve closing buffer assembly 22, and an oil return valve port 27.

[0044] The usage and working principle of this invention are as follows:

[0045] When this invention is used, the oil inlet connector 2 is connected to the pressure source, the oil return connector 5 is connected to the low-pressure oil tank, the electromagnet assembly 19 is controlled by the electronic controller, and the plunger of the plunger assembly 4 can push the intake valve plate to reciprocate through the unloader to open or close it.

[0046] When the two-position three-way high-speed solenoid valve 3 is not energized, the valve core 18, under the spring force of the spring 21, presses against the return oil valve seat 25, closing the return oil valve port 27 and shutting off the return oil valve. Pressurized oil enters the plunger pressure chamber of the plunger assembly 4 through the oil inlet passage composed of the air valve opening buffer assembly 6, the one-way valve 20, the oil inlet port 28 of the two-position three-way high-speed solenoid valve 3, and the control port 29, causing the plunger to move downwards and driving the compressor intake valve to the open position.

[0047] The gas flow control of the continuously variable gas volume regulation system is achieved by delaying the closing time of the compressor intake valve until the compression stage of the compressor piston. The gas supply is controlled by controlling the amount of return gas before the compressor effectively compresses. When the intake valve is about to close, the amount of return gas is relatively large, which acts on the compressor valve and is then transmitted to the plunger. The airflow back thrust on the plunger is relatively large. In order to provide high hydraulic pressure to keep the valve open without increasing the oil supply pressure, a one-way valve is installed in the oil supply channel. At this time, due to the increase in oil pressure in the plunger chamber, both the one-way valve and the return valve are closed, and the oil in the plunger chamber is locked, thus keeping the intake valve in the open position.

[0048] When the two-position three-way high-speed solenoid valve 3 is energized, the electromagnet assembly 19 generates an electromagnetic force on the valve core 18. Under the action of the electromagnetic force, the valve core 18 moves from left to right, opening the return oil valve port 27 to open the return oil passage and closing the inlet oil valve port 28 to close the inlet oil passage. The oil in the plunger pressure chamber passes through the air valve closing buffer piston 23, and the return oil valve port 27 is connected to the oil tank. At this time, due to the backflow force on the air valve plate and the return spring force of the air valve, the plunger moves upward rapidly. Under the action of the hydraulic oil in the return oil passage, in the initial stage, due to the oil pressure, the air valve closing buffer piston 23 moves rapidly to the left along with the hydraulic oil. When the left end face of the air valve closing buffer piston 23 is in contact with the right end face of the return oil valve seat 25, the air valve closing buffer piston 23 stops moving, and most of the return oil passage is cut off, leaving only the two symmetrical throttling orifices 26 on the air valve closing buffer piston 23 for oil return. The return oil flow rate drops rapidly, which in turn causes the plunger, unloader, and valve plate speeds to decrease rapidly until the valve plate slowly sits down, thus achieving a buffer function of fast at first and slow at the next.

[0049] When the diameter of the plunger and the inner and outer diameters of the valve-closing buffer piston 23 are constant, the length of the rapid movement section of the plunger is determined by dimension L2 (the distance between the left end face of the valve-closing buffer piston 23 and the right end face of the return valve seat 25), and the buffering speed is determined by the orifice diameters of the two throttling orifices 26 on the valve-closing buffer piston 23.

[0050] When the piston stops moving upward after the air valve is seated, the hydraulic oil in the return oil passage stops flowing. The pressure difference acting on the air valve closing buffer piston 23 disappears. Under the action of the return spring force of the air valve closing buffer piston return spring 24, the air valve closing buffer piston 23 moves to the right and returns to its original position, preparing for the next cycle.

[0051] When the two-position three-way high-speed solenoid valve 3 is de-energized, the valve core 18 moves from right to left under the restoring force of the spring 21 on the right end armature, closing the return valve port 27 and opening the inlet valve port 28. Pressurized oil enters the plunger pressure chamber from the inlet port 30 through the air valve opening buffer assembly 6, the check valve 20, the inlet valve port 28 of the two-position three-way high-speed solenoid valve 3, and the control port 29, pushing the plunger downwards and opening the compressor air valve. In the initial stage of de-energization of the two-position three-way high-speed solenoid valve 3, under the action of oil pressure, the hydraulic oil and the air valve opening buffer piston 9 together push the plunger downwards rapidly. When the air valve opening buffer piston 9 moves to the point where its lower end face is in contact with the baffle 7, it stops moving. At this time, only the hydraulic oil through the throttle orifice 11 on the air valve opening buffer piston 9 drives the piston downwards. Because the hydraulic oil flow through the throttle orifice 11 decreases rapidly, the plunger's movement speed decreases rapidly until the air valve slowly sits down, thus achieving a buffer function of fast at first and slow later.

[0052] When the diameter of the plunger and the diameter of the valve-opening buffer piston 9 are constant, the length of the rapid movement section of the plunger when the valve is open is determined by L1 (the distance between the lower end face of the valve-opening buffer piston 9 and the upper end face of the baffle 7), and the plunger buffer speed is determined by the throttling orifice 11 on the valve-opening buffer piston 9.

[0053] When the compressor valve is fully open, the hydraulic oil in the oil inlet passage stops flowing, the pressure difference acting on the valve opening buffer piston 9 disappears, and the valve opening buffer piston 9 moves upward to return to its initial position under the action of the valve opening buffer piston return spring 10, preparing for the next cycle.

[0054] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A double-buffered actuator for driving a compressor stepless air volume regulating valve, characterized in that: The actuator body (1) is connected to an oil inlet connector (2) at the top, a two-position three-way high-speed solenoid valve (3) at the middle, a plunger assembly (4) at the bottom, and an oil return connector (5) at the left. The oil inlet connector (2) is provided with a valve opening buffer assembly (6). The two-position three-way high-speed solenoid valve (3) is provided with a valve closing buffer assembly (22). The valve opening buffer assembly (6) includes a baffle (7) located at the lower part of the oil inlet connector (2), a guide bushing (8) in the middle, a valve opening buffer piston (9) in the guide bushing (8), a throttle hole (11) on the valve opening buffer piston (9), and a valve opening buffer piston return spring (10) between the valve opening buffer piston (9) and the baffle (7); a plug (12) is located at the upper part of the guide bushing (8), and a filter screen (13) is located between the plug (12) and the guide bushing (8); The two-position three-way high-speed solenoid valve (3) includes a valve body (17), with the left side of the valve body (17) connected to the return port connector (5), the middle part provided with a valve core (18), the upper middle part provided with a one-way valve (20), and the right side connected to an electromagnet assembly (19); the right side of the valve core (18) is provided with a spring (21); and a pneumatic valve closing buffer assembly (22) is provided between the left side of the valve core (18) and the return port connector (5). The valve closing buffer assembly (22) includes a valve closing buffer piston (23) sleeved on the left side of the valve core (18), a valve closing buffer piston return spring (24) sleeved on the valve closing buffer piston (23), and a return oil valve seat (25) on the left side of the valve closing buffer piston return spring (24). The valve closing buffer piston (23) is provided with two symmetrically arranged throttle holes (26); The right end of the valve seat inner hole (35) of the return valve seat (25) and the left end of the valve core (18) are both set with conical surfaces; the diameter of the valve seat inner hole (35) is equal to the diameter of the valve core guide hole (36) where the valve core (18) is located.

2. The dual-buffered actuator for driving the compressor stepless gas volume regulating valve according to claim 1, characterized in that: The inlet port connector (2) is fitted with an inlet port locking plate (14); the return port connector (5) is fitted with an outlet port locking plate (15); the inlet port locking plate (14) and the outlet port locking plate (15) are respectively connected to the actuator body (1) by fastening screws (16).

3. The dual-buffered actuator for driving the compressor stepless gas volume regulating valve according to claim 1, characterized in that: The return valve seat (25) and the left end of the valve core (18) form the return valve port (27); the middle part of the valve core (18) and the valve body (17) form the inlet valve port (28); the lower part of the valve body (17) and the upper end of the plunger assembly (4) form the control port (29).

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