CN214146071U - Buffer valve for realizing stepless pressure - Google Patents
Buffer valve for realizing stepless pressure Download PDFInfo
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- CN214146071U CN214146071U CN202022764611.7U CN202022764611U CN214146071U CN 214146071 U CN214146071 U CN 214146071U CN 202022764611 U CN202022764611 U CN 202022764611U CN 214146071 U CN214146071 U CN 214146071U
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Abstract
The utility model discloses a buffer valve for realizing stepless pressure, which comprises a steel ball, a main valve core, a first spring, a sliding valve core, a valve body, a pilot valve seat, a spring seat, a second spring, a screw sleeve and a sliding valve sleeve; the valve body is tubular, a step hole is formed in the valve body, a first oil inlet and outlet is formed in the small end, corresponding to the step hole, of the valve body, and a second oil inlet and outlet is formed in the side wall, corresponding to the large end of the step hole, of the valve body; the main valve core is positioned in the step hole, and the end part of the main valve core facing the small end of the step hole is provided with a conical surface; the sliding valve core is a step shaft, the small end of the sliding valve core penetrates through the main valve core, the large end of the sliding valve core is inserted into the sliding valve sleeve, a variable throttling port is formed between the sliding valve core and the main valve core, and a first oil duct is arranged in the sliding valve core. The utility model discloses can alleviate pressure impact on the basis that does not sacrifice main pump volumetric efficiency to improve closed hydraulic system's total efficiency.
Description
Technical Field
The utility model belongs to closed hydraulic system field especially relates to a closed hydraulic system's realization stepless pressure's cushion valve.
Background
The closed hydraulic system comprises an auxiliary pump, a main pump, a filter, a low-pressure overflow valve, a high-pressure overflow valve and a motor. In closed hydraulic system, the sudden change of main pump output flow will force load motor rotational speed state also to take place the sudden change, because the inertial action of load, lead to appearing higher pressure impact easily in the system, prior art suppresses pressure impact with the volumetric efficiency who sacrifices the main pump, but this can seriously reduce closed hydraulic system's volumetric efficiency, has also reduced closed hydraulic system's total efficiency, and the energy consumption increases. Therefore, there is a need for a trim valve that can mitigate pressure surges without sacrificing the volumetric efficiency of the main pump, thereby improving the overall efficiency of the closed hydraulic system.
SUMMERY OF THE UTILITY MODEL
An object of the utility model is to provide a realize the cushion valve of stepless pressure. The utility model discloses can alleviate pressure impact on the basis that does not sacrifice main pump volumetric efficiency to improve closed hydraulic system's total efficiency.
The technical scheme of the utility model: the buffer valve for realizing stepless pressure comprises a steel ball, a main valve core, a first spring, a sliding valve core, a valve body, a pilot valve seat, a spring seat, a second spring, a threaded sleeve and a sliding valve sleeve;
the valve body is tubular, a step hole is formed in the valve body, a first oil inlet and outlet is formed in the small end, corresponding to the step hole, of the valve body, and a second oil inlet and outlet is formed in the side wall, corresponding to the large end of the step hole, of the valve body;
the main valve core is positioned in the step hole, and the end part of the main valve core facing the small end of the step hole is provided with a conical surface;
the sliding valve core is a step shaft, the small end of the sliding valve core penetrates through the main valve core, the large end of the sliding valve core is inserted into the sliding valve sleeve, a variable throttling port is formed between the sliding valve core and the main valve core, a first oil duct is arranged in the sliding valve core, and the steel ball is positioned at the end part of the first oil duct;
the sliding valve sleeve is tubular and is positioned between the sliding valve core and the main valve core, a volume cavity is formed among the sliding valve sleeve, the sliding valve core and the main valve core, the first spring is positioned in the volume cavity, the first spring is connected with the main valve core and the sliding valve sleeve, and the step of the sliding valve core is positioned in the volume cavity;
the pilot valve seat is tubular, one end of the pilot valve seat is in threaded connection with the valve body, and the other end of the pilot valve seat is in threaded connection with the threaded sleeve;
the spring seat is positioned in the pilot valve seat and inserted into the sliding valve sleeve;
one end of the threaded sleeve in threaded connection with the pilot valve seat is opened;
the second spring is arranged in the screw sleeve, one end of the second spring is connected with the inner side bottom surface of the screw sleeve, and the other end of the second spring extends into the pilot valve seat and is connected with the spring seat.
The buffer valve for realizing stepless pressure further comprises a second oil duct, the second oil duct is formed by connecting a gap between the valve body and the main valve core, a gap between the valve body and the sliding valve sleeve and a gap between the sliding valve sleeve and the pilot valve seat in series, one end of the second oil duct is connected with a second oil inlet and outlet, and the other end of the second oil duct is connected to the opening end of the screw sleeve.
In the above-mentioned cushion valve for realizing stepless pressure, there are two second springs, and one of the second springs is located inside the other second spring.
In the above-mentioned buffer valve for realizing stepless pressure, the variable throttle orifice includes two inclined planes symmetrically disposed on two sides of the sliding valve core, one end of the inclined plane is located on the end surface of the sliding valve core facing the first oil inlet/outlet, and the other end is located on the side wall of the sliding valve core located in the large end of the stepped hole.
In the above-mentioned buffer valve for realizing stepless pressure, a screw hole connected with the first oil duct is provided on an end surface of the sliding valve core facing the first oil inlet/outlet, the steel ball is located in the screw hole, an end cap is provided at an outer side end of the screw hole, an oil discharge port is provided on a side wall of the screw hole, a third oil duct and a fourth oil duct are provided on the sliding valve core, one end of the third oil duct is connected with the volume cavity, the other end of the third oil duct is connected with the first oil duct, and one end of the fourth oil duct is connected with the first oil duct, and the other end of the fourth oil duct corresponds to an inner wall of the sliding valve sleeve.
Compared with the prior art, the utility model discloses can carry out effective filtering with the impact pressure who takes place among the closed hydraulic system, when assaulting the power of exerting oneself and taking place, main valve core can be opened fast and close, and the energy that will strike consumes fast, eliminates pressure impact in the twinkling of an eye, with the impact pressure restriction in load required load pressure (the load is different, load pressure is different, the load starts the back, can get into steady operating pressure behind impact pressure, load pressure is the operating pressure after steady). Current closed hydraulic system inserts the utility model discloses, the original high-pressure overflow valve of fungible, consequently, the cost also does not increase. Therefore, the utility model discloses can alleviate pressure impact on the basis that does not sacrifice main pump volumetric efficiency to improve closed hydraulic system's total efficiency.
Drawings
Fig. 1 is a front view of the present invention.
Fig. 2 is a front view of the spool.
Fig. 3 is a state diagram of the utility model when the pressure of the port A exceeds the set highest pressure.
Fig. 4 is a schematic diagram of the present invention.
Fig. 5 is a working curve diagram of the present invention for filtering pressure impact respectively under different maximum set pressures.
The labels in the figures are: 1-a steel ball, 2-a main valve core, 3-a first spring, 4-a sliding valve core, 5-a valve body, 6-a pilot valve seat, 7-a spring seat, 8-a second spring, 9-a screw sleeve, 10-a sliding valve sleeve, 11-a volume cavity, 12-a second oil channel, 13-a plug, 200-a conical surface, 400-a first oil channel, 401-a bevel, 402-a screw hole, 403-an oil outlet, 404-a third oil channel, 405-a fourth oil channel, 500-a stepped hole, 501-a first oil inlet and outlet and 502-a second oil inlet and outlet;
21-auxiliary pump, 22-main pump, 23-filter, 24-low pressure overflow valve, and 26-motor.
Detailed Description
The following description is made with reference to the accompanying drawings and examples, but not to be construed as limiting the invention.
Examples are given. The cushion valve for realizing stepless pressure, as shown in fig. 1, comprises a steel ball 1, a main valve core 2, a first spring 3, a sliding valve core 4, a valve body 5, a pilot valve seat 6, a spring seat 7, a second spring 8, a threaded sleeve 9 and a sliding valve sleeve 10;
the valve body 5 is tubular, a step hole 500 is arranged in the valve body 5, a first oil inlet/outlet 501 is arranged at the small end of the valve body 5 corresponding to the step hole 500, and a second oil inlet/outlet 502 is arranged on the side wall of the valve body 5 corresponding to the large end of the step hole 500;
the main valve element 2 is positioned in the stepped hole 500, the end part of the main valve element 2 facing the small end of the stepped hole 500 is provided with a conical surface 200, the area of the end surface of the main valve element 2 in the stepped hole 500 is smaller than that of the end surface of the other end of the main valve element 2, and the main valve element 2 can slide on the sliding valve sleeve 10;
the sliding valve core 4 is a step shaft, the small end of the sliding valve core 4 penetrates through the main valve core 2, the large end of the sliding valve core 4 is inserted into the sliding valve sleeve 10, a variable throttling port is formed between the sliding valve core 4 and the main valve core 2, a first oil duct 400 is arranged in the sliding valve core 4, and the steel ball 1 is positioned at one end of the first oil duct 400;
the sliding valve sleeve 10 is tubular and is positioned between the sliding valve core 4 and the main valve core 2, a volume cavity 11 is formed among the sliding valve sleeve 10, the sliding valve core 4 and the main valve core 2, the first spring 3 is positioned in the volume cavity 11, the first spring 3 is connected with the main valve core 2 and the sliding valve sleeve 10, and the step of the sliding valve core 4 is positioned in the volume cavity 11;
the pilot valve seat 6 is tubular, one end of the pilot valve seat 6 is in threaded connection with the valve body 5, and the other end of the pilot valve seat 6 is in threaded connection with the threaded sleeve 9;
the spring seat 7 is positioned in the pilot valve seat 6 and inserted into the sliding valve sleeve 10, and the spring seat 7 is in threaded connection with the sliding valve core 4 and blocks the other end of the first oil passage 400;
one end of the threaded sleeve 9, which is in threaded connection with the pilot valve seat 6, is opened;
the second spring 8 is arranged in the threaded sleeve 9, one end of the second spring 8 is connected with the inner side bottom surface of the threaded sleeve 9, and the other end of the second spring extends into the pilot valve seat 6 and is connected with the spring seat 7.
The hydraulic valve further comprises a second oil duct 12, the second oil duct 12 is composed of a gap between the valve body 5 and the main valve element 2, a gap between the valve body 5 and the sliding valve sleeve 10, and a gap between the sliding valve sleeve 10 and the pilot valve seat 6, one end of the second oil duct is connected with the second oil inlet/outlet 502, and the other end of the second oil duct is connected to the opening end of the screw sleeve 9. The sliding valve sleeve 10 and the pilot valve seat 6 are integrally machined on the same blank, the sliding valve sleeve 10 and the pilot valve seat 6 are fixed together, a gap between the sliding valve sleeve 10 and the pilot valve seat 6 is a through hole transversely penetrating between the sliding valve sleeve 10 and the pilot valve seat 6, and the position of the through hole is a position pointed by a reference numeral 12 in fig. 1.
The number of the second springs 8 is two, wherein one second spring 8 is positioned in the other second spring 8.
The variable orifice includes two inclined planes 401 symmetrically disposed at two sides of the sliding valve core 4, one end of the inclined plane 401 is located on the end surface of the sliding valve core 4 facing the first oil inlet/outlet 501, and the other end is located on the side wall of the sliding valve core 4 located in the large end of the stepped hole 500. When the slide valve 4 moves toward the screw sleeve 9, the variable orifice becomes larger, and conversely becomes smaller.
A screw hole 402 connected with the first oil duct 400 is formed in the end face, facing the first oil inlet/outlet port 501, of the sliding valve core 4, the steel ball 1 is located in the screw hole 402, a plug 13 is arranged at the outer end of the screw hole 402, an oil discharge port 403 is formed in the side wall of the screw hole 402, a third oil duct 404 and a fourth oil duct 405 are arranged on the sliding valve core 4, one end of the third oil duct 404 is connected with the volume cavity 11, the other end of the third oil duct is connected with the first oil duct 400, one end of the fourth oil duct 405 is connected with the first oil duct 400, and the other end of the fourth oil duct corresponds to the inner wall of the sliding valve sleeve 10.
The utility model discloses a realize the cushion valve of stepless pressure, indicate, under the arbitrary rank pressure strikes, the cushion valve homoenergetic realizes the cushioning effect.
The working principle is as follows: for convenience of description, the directions "up", "down", "left" and "right" shown in the drawings will be described. As shown in fig. 4, get rid of the high-pressure overflow valve among the current closed hydraulic system, then connect two cushion valves in current closed hydraulic system, the dotted line block diagram shows to be the utility model discloses a cushion valve, the first business turn over hydraulic fluid port 501 and the A mouth of closed hydraulic system of the cushion valve of top are connected, the first business turn over hydraulic fluid port 501 and the C mouth of closed hydraulic system of cushion valve of below are connected, A mouth and C mouth correspond two business turn over hydraulic fluid ports of main pump 22 respectively, and the second business turn over hydraulic fluid port 502 of two cushion valves all is connected on the B mouth with closed hydraulic system (B mouth is between filter 23 and low pressure overflow valve 24).
When the main pump 22 supplies oil to the port a, the port a is a high-pressure port (also an oil outlet of the main pump 22), the port B is a low-pressure port, and the port C is an oil inlet of the main pump 22. When the main pump 22 is discharged, the oil passage between the main pump 22 and the motor 26, i.e., port a, generates an impact pressure, and at this time, the upper cushion valve functions to eliminate the pressure impact of port a, while allowing the lower cushion valve to open port B to replenish oil to port C.
On the contrary, when the main pump 22 supplies oil to the port C, the port C is a high-pressure port, the port B is a low-pressure port, and the port a is an oil inlet of the main pump 22. When the main pump 22 is discharged, the oil passage between the main pump 22 and the motor 26, i.e., the port C, generates impact pressure, and the lower cushion valve functions to eliminate the pressure impact of the port C and allow the lower cushion valve to open the port B to replenish oil to the port a.
The utility model discloses the principle of performance: taking the main pump 22 as an example for supplying oil to the port a, as shown in fig. 1, when there is no rapid pressure change, since the first oil inlet/outlet port 501 is communicated with the volume chamber 11 through the variable throttle, the oil pressure between the first oil inlet/outlet port 501 and the volume chamber 11 is the same, and the force-bearing area of the right side of the main valve element 2 is larger than that of the conical surface 200, the main valve element 2 presses on the valve body 5 under the action of the first spring 3, the first oil inlet/outlet port 501 is not communicated with the second oil inlet/outlet port 502, the steel ball 1 blocks the first oil passage 400 under the action of the oil pressure of the first oil inlet/outlet port 501, no oil flows in the buffer valve, and the buffer valve does not function.
When the pressure of the port a suddenly rises, in the cushion valve on the upper side, the oil of the port a enters the volume chamber 11 from the first oil inlet/outlet 501 through the variable orifice, so that the volume of the volume chamber 11 is increased, the sliding valve core 4 moves to the right, the sliding valve core 4 pushes the spring seat 7 to move to the right, the second spring 8 is compressed, the compression amount of the second spring is associated with the highest set pressure of the system, and different pressure levels correspondingly use the sizes of the variable orifices on different sliding valve cores 4, namely the inclination size of the inclined plane 401. As long as the volume cavity 11 is always changed, a very small pressure difference is generated between the port A and the volume cavity 11, the pressure difference forces the main valve element 2 to move towards the right side, the main valve element 2 is opened, the first oil inlet/outlet 501 is communicated with the second oil inlet/outlet 502, so that the rising speed of system impact pressure is limited, when the system pressure does not rise any more, the volume of the cavity C is not changed, the pressure of the port A is equal to that of the cavity C, the main valve element 2 is forced to be closed, the impact filtering work of pressure is completed, and the stepless pressure buffering function can be realized.
As shown in fig. 3, when the pressure of the port a reaches the highest pressure set by the cushion valve, the sliding valve core 4 moves rightward until the fourth oil duct 405 is located on the right side of the sliding valve sleeve 10, the volume chamber 11 is communicated with the second oil inlet/outlet port 502 through the third oil duct 404, the first oil duct 400, the fourth oil duct 405 and the second oil duct 12, at this time, the pressure of the volume chamber 11 is substantially the same as the pressure of the port B, and is low, the main valve core 2 maintains the maximum opening degree, one part of the oil of the port a is directly discharged from the second oil inlet/outlet port 502 through the first oil inlet/outlet port 501, and the other part of the oil is discharged from the second oil inlet/outlet port 502 through the first oil inlet/outlet port 501, the variable throttle, the volume chamber 11, the third oil duct 404, the first oil duct 400, the fourth oil duct 405 and the second oil duct 12, so as to maintain the maximum pressure of the port a not to rise any more.
In the lower cushion valve, because the port B supplies low-pressure oil (oil supplementing pressure oil, about 2.5 MPa), the left end pressure bearing area of the main valve element 2 is smaller than the right end pressure bearing area, negative pressure is generated in the valve body 5, so that the main valve element 2 moves rightwards, the volume of the volume cavity 11 is reduced, the pressure in the volume cavity 11 is increased, the steel ball 1 is pushed to move leftwards, the first oil duct 400 is opened, oil in the volume cavity 11 enters the port C through the first oil duct 400, the oil discharge port 403 and the first oil inlet/outlet port 501, the main valve element 2 moves rightwards, so that the first oil inlet/outlet port 501 and the second oil inlet/outlet port 502 are communicated, and the oil enters the port C through the second oil inlet/outlet port 502 and the first oil inlet/outlet port 501 in sequence from the port B, so as to complete the oil supplementing operation.
The utility model discloses can alleviate pressure impact on the basis that does not sacrifice main pump volumetric efficiency to improve closed hydraulic system's total efficiency.
Claims (5)
1. Realize the cushion valve of stepless pressure, its characterized in that: the valve comprises a steel ball (1), a main valve core (2), a first spring (3), a sliding valve core (4), a valve body (5), a pilot valve seat (6), a spring seat (7), a second spring (8), a threaded sleeve (9) and a sliding valve sleeve (10);
the valve body (5) is tubular, a step hole (500) is formed in the valve body (5), a first oil inlet and outlet (501) is formed in the small end, corresponding to the step hole (500), of the valve body (5), and a second oil inlet and outlet (502) is formed in the side wall, corresponding to the large end of the step hole (500), of the valve body (5);
the main valve core (2) is positioned in the stepped hole (500), and the end part of the main valve core (2) facing the small end of the stepped hole (500) is provided with a conical surface (200);
the sliding valve core (4) is a step shaft, the small end of the sliding valve core (4) penetrates through the main valve core (2), the large end of the sliding valve core (4) is inserted into the sliding valve sleeve (10), a variable throttling port is formed between the sliding valve core (4) and the main valve core (2), a first oil duct (400) is arranged in the sliding valve core (4), and the steel ball (1) is located at the end part of the first oil duct (400);
the sliding valve sleeve (10) is tubular and is positioned between the sliding valve core (4) and the main valve core (2), a volume cavity (11) is formed among the sliding valve sleeve (10), the sliding valve core (4) and the main valve core (2), the first spring (3) is positioned in the volume cavity (11), the first spring (3) is connected with the main valve core (2) and the sliding valve sleeve (10), and the step of the sliding valve core (4) is positioned in the volume cavity (11);
the pilot valve seat (6) is tubular, one end of the pilot valve seat (6) is in threaded connection with the valve body (5), and the other end of the pilot valve seat is in threaded connection with the threaded sleeve (9);
the spring seat (7) is positioned in the pilot valve seat (6) and inserted into the sliding valve sleeve (10);
one end of the threaded sleeve (9) which is in threaded connection with the pilot valve seat (6) is opened;
the second spring (8) is arranged in the threaded sleeve (9), one end of the second spring (8) is connected with the inner bottom surface of the threaded sleeve (9), and the other end of the second spring extends into the pilot valve seat (6) and is connected with the spring seat (7).
2. The cushion valve for achieving stepless pressure of claim 1, wherein: the hydraulic control valve further comprises a second oil duct (12), the second oil duct (12) is formed by connecting a gap between the valve body (5) and the main valve core (2), a gap between the valve body (5) and the sliding valve sleeve (10) and a gap between the sliding valve sleeve (10) and the pilot valve seat (6) in series, one end of the second oil duct (12) is connected with a second oil inlet and outlet (502), and the other end of the second oil duct is connected to the opening end of the threaded sleeve (9).
3. The cushion valve for achieving stepless pressure of claim 1, wherein: the number of the second springs (8) is two, wherein one second spring (8) is positioned in the other second spring (8).
4. The cushion valve for achieving stepless pressure of claim 1, wherein: the variable throttling opening comprises two inclined planes (401) symmetrically arranged on two sides of the sliding valve core (4), one end of each inclined plane (401) is located on the end face, facing the first oil inlet/outlet (501), of the sliding valve core (4), and the other end of each inclined plane (401) is located on the side wall, located in the large end of the stepped hole (500), of the sliding valve core (4).
5. The cushion valve for achieving stepless pressure of claim 1, wherein: the end face, facing the first oil inlet and outlet opening (501), of the sliding valve core (4) is provided with a screw hole (402) connected with the first oil duct (400), the steel ball (1) is located in the screw hole (402), the outer side end of the screw hole (402) is provided with a plug (13), the side wall of the screw hole (402) is provided with an oil discharge opening (403), the sliding valve core (4) is provided with a third oil duct (404) and a fourth oil duct (405), one end of the third oil duct (404) is connected with the volume cavity (11), the other end of the third oil duct is connected with the first oil duct (400), one end of the fourth oil duct (405) is connected with the first oil duct (400), and the other end of the fourth oil duct corresponds to the inner wall of the sliding valve sleeve (10).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202022764611.7U CN214146071U (en) | 2020-11-25 | 2020-11-25 | Buffer valve for realizing stepless pressure |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202022764611.7U CN214146071U (en) | 2020-11-25 | 2020-11-25 | Buffer valve for realizing stepless pressure |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN214146071U true CN214146071U (en) | 2021-09-07 |
Family
ID=77566618
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202022764611.7U Active CN214146071U (en) | 2020-11-25 | 2020-11-25 | Buffer valve for realizing stepless pressure |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN214146071U (en) |
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2020
- 2020-11-25 CN CN202022764611.7U patent/CN214146071U/en active Active
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