Threaded cartridge valve for buffering hydraulic cylinder

Abstract

The utility model discloses a threaded cartridge valve for buffering a hydraulic cylinder, which relates to the technical field of threaded cartridge valves, and comprises a valve seat and a valve core in sliding connection with the inner wall of the valve seat, a spring cavity is arranged in the valve core, a return spring is arranged between the spring cavity and the valve seat, and a steel cable baffle ring for preventing the valve core from being separated from the inner cavity of the valve seat is arranged in the valve seat. The end, close to the steel wire baffle ring, of the valve seat is a port C, the end, away from the steel wire baffle ring, of the valve seat is a port B, and a port A is formed in the middle end of the valve seat. A throttling hole is formed in the end, close to the port B, of the valve element. The structure is simple and practical, space is saved, the valve seat can be additionally installed at an oil port outside a hydraulic cylinder body, the installation size of the hydraulic cylinder is not occupied, and the design size of the hydraulic cylinder is wider; the buffering effect can be adjusted at will according to the test result, only one buffering cartridge valve needs to be replaced, and the hydraulic cylinder is not damaged; the problem of size foundation leakage of the piston rod of the rod cavity of the hydraulic cylinder is avoided through the throttling hole, and the buffering requirement for extremely low speed can be met.

Description

Technical Field

[0001] The utility model belongs to the technical field of threaded cartridge valves, in particular to a threaded cartridge valve used for hydraulic cylinder buffering. Background Art

[0002] The current hydraulic cylinder needs buffering to reduce the pressure shock or impact of the hydraulic cylinder. The existing hydraulic cylinder buffering structure is to make various buffering structures inside the hydraulic cylinder, which mainly uses the reduction of the hydraulic oil circulation channel to achieve the buffering structure that reduces the cylinder running speed. These traditional buffering structures require a certain structural space and will occupy the installation size of the hydraulic cylinder itself; secondly, the buffering structure processed inside the hydraulic cylinder requires relatively high processing accuracy. Once an error occurs in the processing, the corresponding parts need to be scrapped, wasting a lot of manpower and material resources; furthermore, due to its own structural problems, the rodless cavity is still effective as a buffering structure. Since the rod cavity has a piston rod body, all buffering structures are designed based on the piston rod diameter size, which increases the basic leakage of the buffering gap. It is necessary to achieve extremely high tolerance grades and extremely high coaxiality to meet the customer's buffering control of the cylinder running speed. Especially in some occasions where the buffering speed is required to be extremely low, the basic leakage of the traditional buffering mechanism is far from meeting the customer's requirements. Therefore, it is very important to study a threaded cartridge valve for hydraulic cylinder buffering. Utility Model Content

[0003] The utility model aims to provide a threaded cartridge valve for hydraulic cylinder buffering to solve the problems raised by the above background technology.

[0004] In order to solve the above technical problems, the utility model is achieved through the following technical solutions:

[0005] The utility model discloses a threaded cartridge valve for hydraulic cylinder buffering, comprising a valve seat and a valve core slidably connected to the inner wall of the valve seat, a spring cavity is arranged in the valve core, a reset spring is arranged between the spring cavity and the valve seat, a wire retaining ring is arranged in the valve seat for preventing the valve core from escaping from the inner cavity of the valve seat, one end of the valve seat close to the wire retaining ring is a C port, one end away from the wire retaining ring is a B port, an A port is arranged in the middle end, and a throttling hole is arranged at one end of the valve core close to the B port.

[0006] Furthermore, an O-ring is provided on the valve seat, and the O-ring is located at one end of the valve seat close to the B port.

[0007] Furthermore, the outer wall of one end of the valve seat close to the C port is threaded.

[0008] Furthermore, a sealing line is provided in the valve seat.

[0009] Furthermore, the valve core is provided with a sealing surface capable of sealingly contacting the sealing line.

[0010] Furthermore, a plurality of pressure equalizing grooves are evenly arranged on the outer wall of the valve core.

[0011] Furthermore, there is a sealing level fitting tolerance between the outer wall of the valve core and the inner wall of the valve seat.

[0012] Furthermore, the C port is connected to the pressure guide hole of the hydraulic cylinder, the pressure guide hole is located in the rod chamber of the hydraulic cylinder, the A port is connected to the rod chamber of the hydraulic cylinder, the B port is connected to the T oil port of the hydraulic cylinder, and the P oil port is provided on the rodless chamber of the hydraulic cylinder.

[0013] The utility model has the following beneficial effects: the structure of the application is simple, practical, and space-saving. It can be installed at the oil port outside the hydraulic cylinder body, and can meet various requirements of customers for hydraulic cylinder buffering. It does not occupy the installation size of the hydraulic cylinder itself, and the design size of the hydraulic cylinder is more spacious; the buffering effect can be adjusted at will according to the test results, and only a buffer cartridge valve needs to be replaced without damaging the hydraulic cylinder; the throttle hole avoids the problem of basic leakage caused by the size of the piston rod of the rod cavity of the hydraulic cylinder, and can be used for extremely slow buffering requirements, avoiding the problem of wasting a lot of manpower and material resources due to errors.

[0014] Of course, any product implementing the present invention does not necessarily need to achieve all of the advantages described above at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions of the embodiments of the utility model, the drawings required for describing the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0016] Figure 1 It is a structural schematic diagram of the initial state of a threaded cartridge valve for hydraulic cylinder buffering of the utility model;

[0017] Figure 2 This is a schematic diagram of the valve seat structure of the utility model;

[0018] Figure 3 This is a schematic diagram of the valve core structure of the utility model;

[0019] Figure 4 It is a structural schematic diagram of a threaded cartridge valve used for hydraulic cylinder buffering of the utility model when it plays a buffering role;

[0020] Figure 5 This is a schematic diagram of an application of the utility model;

[0021] Figure 6 This is another application schematic diagram of the utility model;

[0022] Figure 7 It is the hydraulic graphic symbol of the utility model.

[0023] In the figure, 1. valve seat; 2. valve core; 3. O-ring; 4. return spring; 5. wire retaining ring; 6. spring chamber; 7. throttle hole; 8. pressure equalizing groove; 9. sealing surface; 10. A port; 11. B port; 12. C port; 13. thread; 14. sealing line; 15. hydraulic cylinder; 16. rodless chamber; 17. rod chamber; 18. pressure guide hole; 19. T oil port; 20. P oil port. DETAILED DESCRIPTION

[0024] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0025] See also Figure 1-7 As shown, the utility model is a threaded cartridge valve for hydraulic cylinder buffering, comprising a valve seat 1 and a valve core 2 slidably connected to the inner wall of the valve seat 1, a spring chamber 6 is arranged in the valve core 2, a return spring 4 is arranged between the spring chamber 6 and the valve seat 1, a wire retaining ring 5 is arranged in the valve seat 1 for preventing the valve core 2 from escaping from the inner cavity of the valve seat 1, the valve seat 1 has a C port 12 at one end close to the wire retaining ring 5, a B port 11 at one end away from the wire retaining ring 5, an A port 10 is opened at the middle end, and a throttling hole 7 is arranged at one end of the valve core 2 close to the B port 11. In the initial state, the return spring 4 causes the valve core 2 to always contact the wire retaining ring 5, thereby ensuring that the A port 10 and the B port 11 of the valve seat 1 are connected. The throttling hole 7 is arranged on the valve core 2, and after the main oil circuits of the A port 10 and the B port 11 of the valve seat 1 are cut off, they can be connected through the throttling hole 7 on the valve core 2.

[0026] The valve seat 1 is provided with an O-ring 3 , which is located at one end of the valve seat 1 close to the B port 11 .

[0027] The outer wall of one end of the valve seat 1 close to the C port 12 is threaded 13 .

[0028] A sealing line 14 is provided inside the valve seat 1. A sealing surface 9 capable of sealingly contacting the sealing line 14 is provided on the valve core 2. When oil pressure is passed through the C port 12 of the valve seat 1, the oil pressure overcomes the spring force of the return spring 4, forcing the valve core 2 to move leftward until the sealing surface 9 of the valve core 2 hits the sealing line 14 of the valve seat 1, and the valve core 2 stops moving and reaches a hard sealing state at the contact position, thereby cutting off the unblocked A port 10 and B port 11 of the valve seat 1.

[0029] The outer wall of the valve core 2 is evenly provided with a plurality of pressure equalizing grooves 8. The outer wall of the valve core 2 and the inner wall of the valve seat 1 have a sealing level matching tolerance, so that the contact gap between the valve seat 1 and the valve core 2 reaches a sliding sealing state with a small amount of leakage, and the valve core 2 can slide smoothly in the valve seat 1.

[0030] The C port 12 is connected to the pressure guide hole 18 of the hydraulic cylinder 15, and the pressure guide hole 18 is located in the rod chamber 17 of the hydraulic cylinder 15. The A port 10 is connected to the rod chamber 17 of the hydraulic cylinder 15, and the B port 11 is connected to the T oil port 19 of the hydraulic cylinder 15.

[0031] 16 is provided with a P oil port 20.

[0032] The threaded cartridge valve for hydraulic cylinder buffering in the present application is hereinafter referred to as the buffer cartridge valve. The functional mechanism of the buffer cartridge valve is as follows:

[0033] During the hydraulic cylinder retraction process, the hydraulic oil from the pump station enters the oil port T oil port 19 of the rod chamber 17. At this time, the buffer cartridge valve is in the initial free state, and the valve core 2 is pressed against the wire retaining ring 5 by the return spring 4. Figure 1 As shown, at this time, the buffer cartridge valve is in the open state, the A port 10 and the B port 11 are unobstructed, the hydraulic oil reaches the A port 10 through the B port 11, and then enters the rod chamber 17 of the hydraulic cylinder 15 through the oil pipe, pushing the piston rod to retract into the hydraulic cylinder 15, as shown in FIG. Figure 5 As shown. Although at this time there is high-pressure oil in the rod chamber 17 that can enter the C port 12 through the pressure guide hole 18, and the oil pressure acts on the valve core 2, but according to the hydraulic principle, this oil pressure also acts on the spring chamber 6 side of the valve core 2. The valve core 2 is in a balanced state under the action of the oil pressure, but because there is a return spring 4 in the spring chamber 6, the valve core 2 is pressed against the wire retaining ring 5, so during the entire retraction process, the valve is in an open state, that is, the A port 10 and the B port 11 are unobstructed. The hydraulic oil in the rodless chamber 16 is discharged back to the pump station tank through the P oil port 20.

[0034] During the extension process of the hydraulic cylinder, the hydraulic oil from the pump station enters the rodless chamber 16 through the P oil port 20, pushing the piston rod out of the hydraulic cylinder 15. The T oil port 19 of the hydraulic cylinder 15 is connected to the pump station oil tank, and the hydraulic oil in the rod chamber 17 is at approximately zero pressure. At this time, the buffer cartridge valve is in the initial free state, the valve core 2 is in the open state, the A port 10 and the B port 11 are unobstructed, and the hydraulic oil in the rod chamber 17 is pushed by the piston, passes through the oil pipe of the rod chamber 17 to the A port 10, passes through the internal channel of the valve to the B port 11, and then returns to the oil tank through the T oil port 19. When the piston seal ring runs to just pass the pressure guide hole 18, as shown in Figure 6As shown, the pressure-conducting hole 18 and the rodless chamber 16 are at the same high pressure. The high-pressure oil in the rodless chamber 16 reaches the C port 12 through the pressure-conducting hole 18, acts on the valve core 2, and pushes the valve core 2 to move toward the side of the return spring 4 until the sealing surface 9 of the valve core 2 contacts the sealing line 14 of the valve seat 1. Then, the buffer valve is closed, the main oil circuits of the A port 10 and the B port 11 are cut off, and the discharge of the hydraulic oil in the rod chamber 17 of the hydraulic cylinder is blocked. When the hydraulic oil passes through the A port 10, it can only reach the B port 11 through the throttle hole 7 on the valve core 2 and be discharged back to the oil tank. Since the hydraulic oil discharged through the throttle hole 7 is strictly controlled, the hydraulic cylinder 15 enters a low-speed buffer state at this time. At this time, the distance S1 between the piston of the hydraulic cylinder 15 and the front cover is the buffer distance of the hydraulic cylinder 15. By changing the size of the throttle hole 7, the speed and time of the piston rod extension at this time can be controlled. Until the piston rod of the hydraulic cylinder 15 is fully extended, the high-pressure oil in the P oil port 20 is unloaded, and the oil pressure in the rodless chamber 16 is also unloaded at the same time, and then the high-pressure oil in the C port 12 of the buffer valve is also unloaded, and the valve core 2 is restored to the initial free state under the action of the return spring 4, and the A port 10 and the B port 11 are unblocked. One working cycle is completed.

[0035] The present application has a simple, practical and space-saving structure, and can be installed at the oil port outside the hydraulic cylinder body, and can meet various requirements of customers for hydraulic cylinder buffering. It does not occupy the installation size of the hydraulic cylinder 15 itself, and the design size of the hydraulic cylinder 15 is more spacious; the buffering effect can be adjusted at will according to the test results, and only a buffer cartridge valve needs to be replaced without damaging the hydraulic cylinder 15; the throttle hole 7 avoids the basic leakage problem caused by the piston rod size of the rod chamber 17 of the hydraulic cylinder 15, and can be used for extremely slow buffering requirements, avoiding the problem of wasting a lot of manpower and material resources due to errors.

[0036] In the description of this specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0037] The preferred embodiments of the utility model disclosed above are only used to help explain the utility model. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to the specific implementation methods described. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the utility model, so that technicians in the relevant technical field can well understand and use the utility model. The utility model is limited only by the claims and their full scope and equivalents.

Claims

1. A threaded cartridge valve for hydraulic cylinder buffering, comprising a valve seat (1) and a valve core (2) slidably connected to the inner wall of the valve seat (1), characterized in that: The valve core (2) is provided with a spring chamber (6), a return spring (4) is provided between the spring chamber (6) and the valve seat (1), the valve seat (1) is provided with a wire retaining ring (5) for preventing the valve core (2) from escaping from the inner chamber of the valve seat (1), the end of the valve seat (1) close to the wire retaining ring (5) is a C port (12), the end away from the wire retaining ring (5) is a B port (11), the middle end is provided with an A port (10), and the end of the valve core (2) close to the B port (11) is provided with a throttling hole (7).

2. A threaded cartridge valve for hydraulic cylinder buffering according to claim 1, characterized in that: An O-shaped sealing ring (3) is provided on the valve seat (1), and the O-shaped sealing ring (3) is located at one end of the valve seat (1) close to the B port (11).

3. A threaded cartridge valve for hydraulic cylinder buffering according to claim 1, characterized in that: The outer wall of one end of the valve seat (1) close to the C port (12) is threaded (13).

4. A threaded cartridge valve for hydraulic cylinder buffering according to claim 1, characterized in that: A sealing line (14) is provided inside the valve seat (1).

5. A threaded cartridge valve for hydraulic cylinder buffering according to claim 4, characterized in that: The valve core (2) is provided with a sealing surface (9) capable of sealingly contacting the sealing line (14).

6. A threaded cartridge valve for hydraulic cylinder buffering according to claim 1, characterized in that: The outer wall of the valve core (2) is evenly provided with a plurality of pressure equalizing grooves (8).

7. A threaded cartridge valve for hydraulic cylinder buffering according to claim 1, characterized in that: The outer wall of the valve core (2) and the inner wall of the valve seat (1) have a sealing level matching tolerance.

8. A threaded cartridge valve for hydraulic cylinder buffering according to claim 1, characterized in that: The C port (12) is connected to a pressure-conducting hole (18) of a hydraulic cylinder (15), the pressure-conducting hole (18) is located in a rod chamber (17) of the hydraulic cylinder (15), the A port (10) is connected to the rod chamber (17) of the hydraulic cylinder (15), the B port (11) is connected to a T oil port (19) of the hydraulic cylinder (15), and a P oil port (20) is provided on the rodless chamber (16) of the hydraulic cylinder (15).

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