Bidirectional pressure balance valve and oil pump

Abstract

The utility model provides a kind of two-way pressure balance valve and oil pump, including valve shell, first valve core, first elastic element, second valve core and second elastic element, the both ends of valve shell are respectively equipped with with inside first cavity intercommunication A mouth and B mouth, first cavity inside installation has first valve core and first elastic element, first elastic element is used to force the top of first valve core and first cavity top sealing abutment;Second cavity inside installation has second valve core and second elastic element in the middle of first valve core, and second elastic element is used to force the bottom of second valve core and the bottom of second cavity sealing abutment.The utility model is by being provided with two sets of by valve core and elastic element constitute opposite direction check valve structure in valve shell, so that valve body can automatically balance the pressure change inside and outside oil pump;When oiling, oil liquid can be directly injected from the oil inlet of valve shell, the sealing of oil pump can be kept at all times by check valve structure after oiling ends;Avoid the problem such as dust impurity caused by frequently unscrewing oiling plug.

Description

Technical Field

[0001] This utility model relates to the field of bidirectional pressure balancing valve technology, and in particular to a bidirectional pressure balancing valve and an oil pump. Background Technology

[0002] In existing heavy-duty truck cab tilting hydraulic systems, a traditional oil filler plug structure is commonly used to achieve oil filling and internal / external air pressure balance in the oil pump housing. This oil filler plug is typically a screw-on plug structure with a vent hole, which is directly screwed onto the oil filler port of the oil pump housing. Its basic principle is that the small hole in the center of the plug allows air to pass through the housing. When the oil in the system expands due to heat or when the cab is lifted, causing the oil to overflow and the internal pressure to rise, gas or excess oil can be discharged through this hole. When the internal oil pressure drops and forms a negative pressure, external air can also be introduced through this hole, thereby maintaining pressure balance and preventing pumping difficulties or housing deformation.

[0003] However, traditional oil filler plugs require unscrewing to add oil when needed. This frequent unscrewing and re-screwing makes the plug highly susceptible to dust and impurities, accelerating contamination and wear in the hydraulic system. Therefore, there is an urgent need for a bidirectional pressure balancing valve that can effectively isolate contaminants. Utility Model Content

[0004] This invention proposes a bidirectional pressure balancing valve and oil pump, which solves the problems in the prior art where dust and impurities easily enter the oil injection plug during frequent opening and oil injection, accelerating the pollution and wear of the hydraulic system.

[0005] The technical solution of this utility model is implemented as follows: The first aspect of this utility model provides a bidirectional pressure balancing valve, including a valve housing, a first valve core, a first elastic element, a second valve core, and a second elastic element. The valve housing has an A port and a B port at both ends, respectively communicating with an internal first cavity. The A port and B port are respectively connected to the oil injection port of an oil pump and the outside atmosphere. The first valve core and the first elastic element are installed inside the first cavity. The first elastic element forces the top outer wall of the first valve core to seal against the top inner wall of the first cavity. The second valve core and the second elastic element are installed in a second cavity in the middle of the first valve core. The two ends of the second cavity are respectively connected to the A port and the B port. The second elastic element forces the bottom outer wall of the second valve core to seal against the bottom inner wall of the second cavity.

[0006] Preferably, the top of the first valve core is conical, the top inner wall of the first cavity matches the top conical surface of the first valve core, and a first sealing ring is provided on the contact surface between the top outer wall of the first valve core and the top inner wall of the first cavity.

[0007] Specifically, the valve housing has an open port B, and a first plug is detachably installed at the port B. The first plug has an axial through hole in the middle, and the two ends of the first elastic element abut against the first valve core and the first plug, respectively.

[0008] Specifically, the bottom of the first valve core is provided with an installation groove that communicates with the second cavity. The second sealing ring and the second plug are installed in sequence in the installation groove. The middle of the second plug is provided with an axial through hole. The top surface of the second cavity is provided with an axial through hole. The two ends of the second elastic element abut against the top surface of the second cavity and the second valve core, respectively.

[0009] Preferably, both the first elastic element and the second elastic element are compression springs.

[0010] Preferably, an extension tube is detachably connected to the A port end of the valve housing.

[0011] The second aspect of this utility model provides an oil pump, wherein the oil pump's oil inlet is equipped with the aforementioned bidirectional pressure balancing valve.

[0012] Compared with the prior art, the beneficial effects of this utility model are as follows: (1) This utility model cleverly sets two sets of one-way valve structures with opposite directions, consisting of valve cores and elastic elements, inside the valve body, so that the valve body can automatically balance the pressure changes inside and outside the oil pump; when oil needs to be injected, there is no need to unscrew the balance valve, and oil can be injected directly from the oil injection port of the valve body. The oil pressure will force the one-way valve structure corresponding to the first valve core inside to open temporarily, allowing the oil to flow into the oil pump in one direction; after the pressure disappears after the oil injection is finished, the one-way valve structure will automatically close under the action of the elastic element, ensuring that the oil will not flow back and maintaining the sealing of the oil pump at all times; fundamentally avoiding the problem of introducing dust and impurities due to frequent unscrewing of the oil injection plug, while ensuring the reliability of the oil pump seal; (2) By designing the top of the first valve core and the top of the valve cavity as a conical surface fit and adding a sealing ring, the conical sealing form has better sealing performance than the planar sealing form and can withstand higher pressure without leakage; the setting of the first sealing ring ensures that the seal is always effective when the system pressure fluctuates, prevents abnormal pressure leakage, and improves the overall service life and reliability of the valve body. (3) This utility model adopts a detachable plug design with a central through hole in the mounting groove of the B port of the valve body and the bottom of the first valve core. During assembly, the spring can be easily compressed and the required preload can be set by screwing the first plug. During maintenance, the valve core, spring and other parts inside can be inspected or replaced simply by removing the plug. This greatly facilitates the assembly of the product, the adjustment of the preload of the internal parts and subsequent maintenance and replacement. (4) By providing a detachable extension tube at the A port end, the present invention can guide the discharged oil-gas mixture to a specific position away from the oil pump housing before discharge, thereby avoiding the overflowing oil from flowing directly onto the outer surface of the oil pump to form oil stains and grease that are difficult to remove, keeping the appearance of the pump assembly clean, and preventing oil stains from affecting the normal function of other surrounding components. Attached Figure Description

[0013] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0014] Figure 1 This is a schematic diagram of the internal structure of a bidirectional pressure balancing valve according to the present invention; Figure 2 This is a schematic diagram of the state when a negative pressure is formed inside the oil pump in an embodiment of this utility model; Figure 3 This is a schematic diagram of the state when the internal pressure of the oil pump is too high in this embodiment of the present invention; Figure 4 This is a schematic diagram of the external structure of the oil pump of this utility model; In the diagram: 1. Valve housing; 2. First valve core; 3. First elastic element; 4. Second valve core; 5. Second elastic element; 6. First cavity; 7. Port A; 8. Port B; 9. Second cavity; 10. First sealing ring; 11. First plug; 12. Second sealing ring; 13. Second plug; 14. Connecting hole; 15. Extension pipe; 16. Oil pump. Detailed Implementation

[0015] The technical solution of this utility model will be clearly and completely described below with reference to its embodiments. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0016] Reference Figures 1 to 3The first aspect of this utility model provides a bidirectional pressure balancing valve, including a valve housing 1, a first valve core 2, a first elastic element 3, a second valve core 4, and a second elastic element 5. The valve housing 1 has an A port 7 and a B port 8 at its two ends, respectively, communicating with an internal first cavity 6. The A port 7 and B port 8 are respectively connected to the oil injection hole of an oil pump 16 and the outside atmosphere. The first valve core 2 and the first elastic element 3 are installed inside the first cavity 6. The first elastic element 3 is used to force the top outer wall of the first valve core 2 to seal against the top inner wall of the first cavity 6. The second valve core 4 and the second elastic element 5 are installed in a second cavity 9 in the middle of the first valve core 2. The two ends of the second cavity 9 are respectively connected to the A port 7 and the B port 8. The second elastic element 5 is used to force the bottom outer wall of the second valve core 4 to seal against the bottom inner wall of the second cavity 9.

[0017] This invention cleverly incorporates two sets of one-way valve structures, each composed of a valve core and an elastic element, arranged in opposite directions within the valve housing 1. This allows the valve body to automatically balance pressure changes inside and outside the oil pump 16. When oil injection is required, there is no need to unscrew the balancing valve; oil can be directly injected through the oil injection port of the valve housing 1. The oil pressure forces the one-way valve structure corresponding to the first valve core 2 inside to temporarily open, allowing oil to flow into the oil pump 16 in one direction. After the pressure disappears after oil injection, the one-way valve structure automatically closes under the action of the elastic element, ensuring that the oil does not flow back and maintaining the sealing of the oil pump 16 at all times. This fundamentally avoids the problem of introducing dust and impurities due to frequent unscrewing of the oil injection plug, while ensuring the reliability of the oil pump 16's seal.

[0018] Preferably, such as Figure 1 As shown, the top of the first valve core 2 is conical, and the inner wall of the top of the first cavity 6 matches the conical surface of the top of the first valve core 2. A first sealing ring 10 is provided at the contact surface between the outer wall of the top of the first valve core 2 and the inner wall of the top of the first cavity 6. By designing the top of the first valve core 2 and the top of the valve cavity to be conical and adding a sealing ring, the conical sealing form has better sealing performance than the planar sealing, and can withstand higher pressure without leakage. The setting of the first sealing ring 10 ensures that the seal is always effective when the system pressure fluctuates, preventing abnormal pressure leakage and improving the overall service life and reliability of the valve body.

[0019] Specifically, such as Figure 1As shown, the valve housing 1 has an open port B 8, and a first plug 11 is detachably installed at port B 8. The first plug 11 has an axially penetrating through hole in its center. The two ends of the first elastic element 3 abut against the first valve core 2 and the first plug 11, respectively. By adopting a detachable plug design with a central through hole at port B 8 of the valve housing 1, the spring can be easily compressed and the required preload set by screwing the first plug 11 during assembly. During maintenance, the valve core, spring, and other internal parts can be inspected or replaced simply by removing the first plug 11, greatly facilitating product assembly, adjustment of the preload of internal components, and subsequent maintenance and replacement.

[0020] Specifically, such as Figure 1 As shown, the bottom of the first valve core 2 is provided with an installation groove communicating with the second cavity 9. The second sealing ring 12 and the second plug 13 are installed in sequence in the installation groove. The second plug 13 is provided with an axial through hole in the middle. The top surface of the second cavity 9 is provided with an axial through hole 14 in the center. The two ends of the second elastic element 5 abut against the top surface of the second cavity 9 and the second valve core 4, respectively. By installing the second sealing ring 12 and the second plug 13 in sequence in the installation groove at the bottom of the first valve core 2, the sealing reliability and stability are improved by the abutment and sealing between the second sealing ring 12 and the second valve core 4. The setting of the second plug 13 facilitates the installation and replacement of the second valve core 4, the spring, and the second sealing ring 12.

[0021] Preferably, such as Figure 1 As shown, the first elastic element 3 and the second elastic element 5 are both compression springs, but other elastic elements with the same or similar physical properties can also be used instead.

[0022] In this embodiment, as Figure 1 As shown, the second valve core 4 can be a steel ball, or it can be made of other shapes (such as a conical valve core) or materials.

[0023] Preferably, such as Figure 1 , 4 As shown, an extension tube 15 is detachably connected to the A port 7 end of the valve housing 1. By setting a detachable extension tube 15 at the A port 7 end, the extension tube 15 can guide the discharged oil-gas mixture to a specific position away from the oil pump 16 housing before discharge, avoiding the overflowing oil from flowing directly onto the outer surface of the oil pump 16 to form hard-to-remove oil stains and grease, keeping the appearance of the pump assembly clean, and preventing oil stains from affecting the normal function of other surrounding components.

[0024] In this embodiment, the extension tube 15 is a flexible tube with an elbow, which makes it easy to change the direction of the extension tube 15, making the overall structure of the oil pump 16 more compact, and also makes it easier to adjust the outlet position of the extension tube 15 when needed. The extension tube 15 can be fixed to the housing of the oil pump 16 by a buckle.

[0025] like Figure 4 As shown, the second aspect of this utility model provides an oil pump, wherein the oil pump 16 is equipped with the aforementioned bidirectional pressure balance valve at its oil inlet.

[0026] In this embodiment, the B port 8 of the valve housing 1 is connected to the oil injection port of the oil pump 16 through a threaded joint. In a specific implementation, the A port 7 of the valve housing 1 can also be connected to the oil injection port of the oil pump 16, while the B port 8 is connected to the outside atmosphere.

[0027] The working process of the bidirectional pressure balancing valve in this embodiment is as follows: 1) The internal pressure of oil pump 16 is normal, and the two-way pressure balance valve is in the closed state. like Figure 1 As shown, when the internal pressure of the oil pump 16 is basically equal to the external atmospheric pressure, the first elastic element 3 forces the top conical surface of the first valve core 2 to tightly seal against the top inner wall of the first cavity 6 of the valve housing 1 (with the help of the first sealing ring 10), while the second elastic element 5 forces the bottom of the second valve core 4 to seal against the second sealing ring 12 in the mounting groove. At this time, both passages between port A 7 and port B 8 are closed, the inside of the oil pump 16 is isolated from the external environment, the system remains sealed, and impurities are prevented from entering and oil leakage is prevented.

[0028] 2) When a negative pressure is generated inside the oil pump 16, the first check valve opens to replenish air.

[0029] like Figure 2 As shown, when the internal oil pressure of the oil pump 16 decreases due to temperature drop or pumped oil, forming a negative pressure, the external atmospheric pressure is higher than the internal pressure. This pressure difference acts on the first valve core 2, overcoming the elastic force of the first elastic element 3, and pushes the first valve core 2 downward, causing its top conical surface to separate from the top surface of the valve cavity, forming a gap. External air is then drawn in from port A 7, flows in through the gap between the valve housing 1 and the first valve core 2 (the sliding contact surfaces of the valve housing 1 and the first valve core 2 are clearance fit), and finally enters the interior of the oil pump 16 housing through port B 8. Figure 2 In the image, the arrow indicates the airflow path for intake, thus quickly balancing the internal and external pressures and ensuring the normal operation of the oil pump 16.

[0030] 3) The internal pressure of oil pump 16 is too high, and the second check valve opens to release air and discharge oil.

[0031] like Figure 3As shown, when the pressure inside the oil pump 16 increases due to temperature rise or overfilling of the cab during lifting, the internal pressure is greater than the external atmospheric pressure. High-pressure fluid enters through port B 8, acting on the bottom of the second valve core 4, overcoming the elastic force of the second elastic element 5, and pushing the second valve core 4 upwards, causing its bottom surface to separate from the second sealing ring 12, forming a gap. Excess gas and oil then flow in through the gap between the second valve core 4 and the second cavity 9 (the sliding contact surfaces of the second valve core 4 and the second cavity 9 are clearance fit), and are finally guided from port A 7 (or the extension pipe 15 connected to port A 7) through the second cavity 9 and the connecting hole 14 at the top, and discharged to a specific external location. Figure 3 In the diagram, the arrows indicate the paths for venting or draining oil, effectively preventing excessive pressure and avoiding oil contamination of the pump body surface.

[0032] 4) Add oil through port A7, the first check valve opens.

[0033] When hydraulic oil needs to be added to the oil pump 16, the oil injection device is connected through port A7. Under the pressure of the injected oil, its operation is the same as the second-stage negative pressure air injection principle: the oil pressure pushes the first valve core 2 to compress the first elastic element 3 and move it downward, causing its top conical surface to separate from the top surface of the valve cavity to form a gap. The oil then flows in through the gap between the valve housing 1 and the first valve core 2 (the sliding contact surfaces of the valve housing 1 and the first valve core 2 are clearance fit), and finally enters the interior of the oil pump 16 housing through port B8. After the oil injection is completed, the oil pressure disappears, and the first elastic element 3 pushes the first valve core 2 to reset and reseal. The entire process does not require disassembly of any parts, eliminating the risk of contaminant intrusion.

[0034] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A bidirectional pressure balancing valve, characterized in that, The system includes a valve housing (1), a first valve core (2), a first elastic element (3), a second valve core (4), and a second elastic element (5). The valve housing (1) has an A port (7) and a B port (8) at both ends that communicate with the internal first cavity (6). The A port (7) and the B port (8) are respectively connected to the oil injection hole of the oil pump (16) and the outside atmosphere. The first cavity (6) is equipped with the first valve core (2) and the first elastic element (3). The first elastic element (3) is used to force the top outer wall of the first valve core (2) to seal against the top inner wall of the first cavity (6). The second cavity (9) in the middle of the first valve core (2) is equipped with the second valve core (4) and the second elastic element (5). The two ends of the second cavity (9) are connected to the A port (7) and the B port (8) respectively. The second elastic element (5) is used to force the bottom outer wall of the second valve core (4) to seal against the bottom inner wall of the second cavity (9).

2. The bidirectional pressure balancing valve as described in claim 1, characterized in that, The top of the first valve core (2) is conical, the top inner wall of the first cavity (6) matches the top conical surface of the first valve core (2), and the contact surface between the top outer wall of the first valve core (2) and the top inner wall of the first cavity (6) is provided with a first sealing ring (10).

3. The bidirectional pressure balancing valve as described in claim 1, characterized in that, The valve housing (1) has an open port (8) and a first plug (11) is detachably installed on the port (8). The first plug (11) has an axial through hole in the middle. The two ends of the first elastic element (3) abut against the first valve core (2) and the first plug (11) respectively.

4. A bidirectional pressure balancing valve as described in claim 1, characterized in that, The bottom of the first valve core (2) is provided with an installation groove that communicates with the second cavity (9). The second sealing ring (12) and the second plug (13) are installed in the installation groove in sequence. The middle part of the second plug (13) is provided with an axial through hole. The center of the top surface of the second cavity (9) is provided with an axial through hole (14). The two ends of the second elastic element (5) abut against the top surface of the second cavity (9) and the second valve core (4) respectively.

5. A bidirectional pressure balancing valve as described in claim 1, characterized in that, Both the first elastic element (3) and the second elastic element (5) are compression springs.

6. A bidirectional pressure balancing valve as described in claim 1, characterized in that, An extension tube (15) is detachably connected to the A port (7) end of the valve body (1).

7. An oil pump, characterized in that, The oil pump (16) is equipped with a bidirectional pressure balancing valve as described in any one of claims 1 to 6 at its oil inlet.

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