Gear pump

Abstract

A gear pump comprises a shell, and a gear set and a flow channel are arranged in the shell. The gear set comprises a pair of meshed gears, and one gear is connected with a motor; the flow channel is divided into a first flow channel and a second flow channel with the meshing position of the gear set as the boundary. The shell comprises an upper cover, a middle plate and a lower shell, the upper cover, the middle plate and the lower shell are matched to form an inner cavity for mounting the gear set, and the thickness of the middle plate is equal to that of the gear; elastic rings are arranged on the inner walls, corresponding to the gear end face, of the upper cover and the lower shell and abut against the gear end face. When the elastic ring is compressed to the limit under the action of oil pressure, the inner walls of the upper cover and the lower shell abut against the end face of the gear. Compared with the prior art, by means of the design of the elastic ring, pressure response type self-adaptive gap adjustment can be achieved, a complex hydraulic compensation mechanism of a traditional floating side plate is avoided, the defect that high-pressure efficiency and low-pressure efficiency cannot be considered at the same time in the design of a fixed gap is overcome, the internal structure of a pump body is greatly simplified, and the manufacturing cost is reduced.

Description

Technical Field

[0001] This utility model belongs to the field of gear pump technology, and specifically relates to a gear pump. Background Technology

[0002] The existing gear pump end face clearance design is mainly divided into two technical routes: fixed clearance and floating clearance. The two have significant differences in performance and each has its own limitations.

[0003] Fixed clearance design typically maintains a constant clearance between the gear end face and the pump body wall through mechanical limiting or pre-tightening structures (such as O-rings, metal gaskets, etc.). This design can effectively reduce leakage loss and improve volumetric efficiency under high pressure conditions, but its disadvantage is that under low pressure or no-load conditions, the fixed clearance cannot be dynamically adjusted with pressure changes, resulting in continuous contact between the gear end face and the pump body wall or an excessively small clearance, which leads to increased frictional loss. Long-term operation can easily cause wear and shorten the service life of the gear and pump body.

[0004] Floating clearance design achieves dynamic clearance adjustment through hydraulic compensation mechanisms (such as floating side plates, elastic elements, etc.). Its advantage lies in automatically increasing the clearance under low pressure or no-load conditions, reducing frictional losses and extending component life. However, this design relies on complex hydraulic control or precise response of elastic elements, making it difficult to completely eliminate leakage under high-pressure conditions. Furthermore, the complex structure of the floating mechanism increases manufacturing costs and the risk of failure. For example, traditional floating side plates require clearance adjustment via hydraulic oil pressure differential or independent springs; their response speed and stability are easily affected by oil contamination or temperature changes, leading to unreliable high-pressure sealing performance.

[0005] In summary, fixed clearances cannot meet the low-friction requirements of low-pressure conditions, while floating clearances struggle to maintain sealing reliability under high-pressure conditions. Therefore, how to integrate the advantages of both in a single structure, achieving a balance between sealing performance under high-pressure conditions and low friction loss under low-pressure conditions, while simultaneously simplifying the mechanism and reducing costs, has become a pressing technical challenge in the gear pump industry. Utility Model Content

[0006] To solve the above-mentioned technical problems, the present invention provides the following technical solution.

[0007] A gear pump includes a housing, within which a gear set and a flow channel are disposed. The gear set includes a pair of meshing gears, one of which is connected to a motor. The flow channel is divided into a first flow channel and a second flow channel, with the meshing point of the gear set as the boundary. The housing includes an upper cover, a middle plate, and a lower shell, which fit together to form an inner cavity for mounting the gear set. The thickness of the middle plate is equal to the thickness of the gear. Elastic rings are disposed on the inner walls of the upper cover and the lower shell corresponding to the gear end faces, and the elastic rings abut against the gear end faces. When the elastic rings are compressed to their limit under hydraulic pressure, the inner walls of the upper cover and the lower shell abut against the gear end faces.

[0008] Furthermore, both the first and second flow channels include a main flow channel. The main flow channel is provided with an oil inlet and an oil outlet. Oil enters the gear pump from the oil inlet, which is equipped with a flow-limiting valve that allows only one-way oil inflow. The oil outlet of the first flow channel is connected to a first pressurizing chamber, which is provided with a first oil outlet. The oil outlet of the second flow channel is connected to a second pressurizing chamber, which is provided with a second oil outlet. Both the first and second pressurizing chambers are equipped with one-way valves that allow only one-way oil outflow. The first and second pressurizing chambers are connected by a pressure regulating groove, which is equipped with a movable reciprocating valve.

[0009] Furthermore, the one-way valve includes a valve body, a valve cavity is provided inside the valve body, a valve core and a reset elastic element are installed in the valve cavity; the valve body is provided with an inlet and an outlet communicating with the valve cavity, and the valve core opens or closes the inlet with the support of the reset elastic element; the valve core is provided with a corresponding inlet and a sealing element that can close the inlet.

[0010] Furthermore, a control head is provided on the valve core. When the check valve is closed, the control head is located inside the inlet. The control head is a frustum-shaped structure with a larger bottom and a smaller top, and the lower part of the control head is connected to the valve core. The inlet is cylindrical.

[0011] Furthermore, the valve core includes a housing and an inner core, the inner core including an assembly part, the assembly part being assembled and fixed to the housing by a locking block; the control head is connected to the assembly part via a neck, the outer diameter of the neck being smaller than that of the control head, and a seal is assembled on the neck.

[0012] Furthermore, the valve core has a prismatic structure, and the space inside the valve cavity for assembling the valve core is cylindrical, with a gap between the side of the prismatic structure and the inner wall of the valve cavity for oil flow.

[0013] Furthermore, the seal protrudes from the end face of the valve core, and the valve core has several protrusions on the end face where the seal is assembled, with the protrusion height of the seal being greater than the height of the protrusions.

[0014] Furthermore, the first pressurizing chamber and the second pressurizing chamber are arranged horizontally symmetrically with respect to the pressure regulating groove; the first flow channel and the second flow channel are arranged horizontally symmetrically with respect to the gear set.

[0015] Furthermore, the main channel has a first oil groove on one side near the meshing point of the gear set and a second oil groove on the other side. The first oil groove is located on the upper cover and the second oil groove is located on the lower shell. The upper cover and the lower shell are provided with mounting grooves for installing elastic rings, and a third oil groove is provided on the side of the mounting groove.

[0016] Compared with the prior art, this application has the following beneficial technical effects:

[0017] 1. Through the design of the elastic ring inside the gear pump cavity, this application enables pressure-responsive adaptive clearance adjustment (or semi-fixed clearance adjustment): Under the action of high-pressure oil, the elastic ring is compressed to its limit, forming a fixed clearance between the gear end face and the inner wall of the pump body, significantly reducing leakage loss under high-pressure conditions and improving volumetric efficiency; when the oil pressure decreases, the elastic ring restores its deformation capacity, allowing a dynamic compensation clearance to form between the gear end face and the pump body, reducing frictional losses under low-pressure or no-load conditions and extending the service life of the gear and the pump body. This structure achieves adaptive switching of clearance between high and low pressure conditions through a single elastic element, avoiding the complex hydraulic compensation mechanism of traditional floating side plates and overcoming the defect that fixed clearance design cannot simultaneously achieve high and low pressure efficiency, greatly simplifying the internal structure of the pump body and reducing manufacturing costs.

[0018] 2. The flow-limiting valve installed in the flow channel can ensure stable oil inlet pressure and reduce the impact of pressure fluctuations on gear meshing stability; the one-way valve achieves precise control of oil outlet pressure and blocks oil backflow through the cooperation of the valve core and the reset elastic element. Combined with the movable reciprocating valve in the pressure regulating tank, it makes the oil outlet stable and avoids intermittent situations.

[0019] 3. The check valve maintains pressure by sealing the inlet with a seal. The higher the hydraulic pressure flowing back into the valve chamber, the greater the reverse pressure on the seal, resulting in a better seal and superior pressure-holding performance. This design effectively prevents oil leakage under high pressure, ensuring the check valve can stably maintain the predetermined pressure under various operating conditions, thus improving the reliability and stability of the system. The valve core adopts a prismatic structure, with a gap between its side and the inner wall of the valve chamber for oil flow. This design not only simplifies the structure but also improves the oil flow efficiency and reduces resistance and energy loss during oil flow.

[0020] 4. The valve core has several protrusions on the end face where the seal is assembled. These protrusions provide excellent protection for the seal. When the hydraulic pressure is too high, the protrusions will bear the pressure before the seal, preventing damage to the seal due to overpressure. Protected by these protrusions, the rubber seal maintains good sealing performance for a long time, significantly extending the service life of the check valve and reducing equipment maintenance costs and replacement frequency.

[0021] 5. The symmetrical layout and layered design of the flow channels and oil grooves significantly optimize the uniformity of oil flow and its anti-contamination capability within the pump: The first and second oil grooves are respectively located on the upper cover and lower shell, forming a connected loop through a third oil groove on the side of the mounting groove, making the oil distribution in the gear meshing area more uniform. This three-dimensional oil circuit design not only reduces pressure pulsation caused by local oil stagnation but also mitigates frictional heat accumulation on the gear end faces through multi-path oil circulation. Simultaneously, the symmetrical structure reduces uneven flow distribution caused by assembly deviations, improving the pump's volumetric efficiency stability under complex operating conditions.

[0022] These technological improvements work together to enable the gear pump of this application to maintain low leakage and high efficiency under high pressure conditions, reduce frictional losses under low pressure or no-load conditions, and significantly improve the pump's overall performance, reliability and environmental adaptability through multi-stage pressure control and adaptive sealing design, providing a better energy-saving and long-life operation solution for hydraulic systems. Attached Figure Description

[0023] Figure 1 This is a 3D view of a gear pump.

[0024] Figure 2 This is a cross-sectional view of the gear pump at the gear.

[0025] Figure 3 Top view of the assembly of the middle plate and lower shell.

[0026] Figure 4 For the middle plate and lower shell Figure 3 AA in the middle is a three-dimensional sectional view of the cutting line.

[0027] Figure 5 This is a 3D view of the top cover.

[0028] Figure 6 This is a three-dimensional view of the lower shell.

[0029] Figure 7 A cross-sectional view of the gear pump at the pressurization chamber.

[0030] Figure 8 for Figure 7 A magnified view of a section at point B in the middle.

[0031] Figure 9 This is an exploded view of a gear pump.

[0032] The following is an explanation of the markings in the accompanying drawings:

[0033] 100. Shell; 101. First flow channel; 102. Second flow channel; 103. Main flow channel; 104. Oil outlet channel; 105. Oil inlet channel; 106. Flow restrictor valve; 110. Top cover; 111. First oil groove; 112. Third oil groove; 120. Middle plate; 130. Lower shell; 131. Second oil groove; 140. Gear; 150. Elastic ring;

[0034] 200, First pressurizing chamber; 201, First oil inlet; 202, First oil outlet; 210, Second pressurizing chamber; 211, Second oil inlet; 212, First oil outlet; 220, Check valve; 221, Valve body; 222, Inlet; 223, Outlet; 224, Valve core; 225, Reset elastic element; 226, Seal; 227, Control head; 228, Protrusion; 230, Reciprocating valve. Detailed Implementation

[0035] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0036] In the following embodiments, the same or similar reference numerals denote the same or similar components or components with the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0037] In the description of this utility model, it should be understood that the terms such as center, longitudinal, transverse, length, width, thickness, upper, lower, front, back, left, right, vertical, horizontal, top, bottom, inner, outer, clockwise, and counterclockwise, indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description; therefore, they should not be construed as limitations on this utility model. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features shown. In the description of this utility model, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," etc., should be interpreted broadly, and those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0038] Reference Figures 1 to 9A gear pump includes a housing 100, within which a gear set and a flow channel are disposed. The gear set includes a pair of meshing gears 140, one of which is connected to a motor. The flow channel is divided into a first flow channel 101 and a second flow channel 102, with the meshing point of the gear set as the boundary. The housing 100 includes an upper cover 110, a middle plate 120, and a lower shell 130, which cooperate to form an inner cavity for mounting the gear set. The thickness of the middle plate 120 is equal to the thickness of the gear 140. Elastic rings 150 are disposed on the inner walls of the upper cover 110 and the lower shell 130 corresponding to the end faces of the gear 140, and the elastic rings 150 abut against the end faces of the gear 140. When the elastic rings 150 are compressed to their limit under hydraulic pressure, the inner walls of the upper cover 110 and the lower shell 130 abut against the end faces of the gear 140. Both the first flow channel 101 and the second flow channel 102 include a main flow channel 103. The main flow channel 103 is provided with an oil inlet channel 105 and an oil outlet channel 104. Oil enters the gear pump from the oil inlet channel 105. The oil inlet channel 105 is equipped with a flow-limiting valve 106 that allows only one-way oil inflow. The oil outlet channel 104 of the first flow channel 101 is connected to a first pressurizing chamber 200. The first pressurizing chamber 200 is provided with a first oil inlet 201 and a first oil outlet 202. The oil outlet channel 104 of the second flow channel 102 is connected to a second pressurizing chamber 210. The second pressurizing chamber 210 is provided with a first oil inlet 201 and a second oil outlet. Both the first pressurizing chamber 200 and the second pressurizing chamber 210 are equipped with a one-way valve 220 that allows only one-way oil outflow. The first pressurizing chamber 200 and the second pressurizing chamber 210 are connected by a pressure regulating groove. The pressure regulating groove is equipped with a movable reciprocating valve 230. The flow-limiting valve 106 installed in the flow channel can ensure stable oil inlet pressure and reduce the impact of pressure fluctuations on the meshing stability of gear 140; the one-way valve 220 achieves precise control of oil outlet pressure through the cooperation of valve core 224 and reset elastic element 225, and combined with the movable reciprocating valve 230 in the pressure regulating groove, it makes the oil outlet stable and avoids intermittent situations.

[0039] This application, through the design of the elastic ring 150 inside the gear pump cavity, enables pressure-responsive adaptive clearance adjustment (or semi-fixed clearance adjustment): Under the action of high-pressure oil, the elastic ring 150 is compressed to its limit, forming a fixed clearance between the end face of the gear 140 and the inner wall of the pump body, significantly reducing leakage loss under high-pressure conditions and improving volumetric efficiency; when the oil pressure decreases, the elastic ring 150 restores its deformation capacity, allowing a dynamic compensation clearance to form between the end face of the gear 140 and the pump body, reducing frictional losses under low-pressure or no-load conditions and extending the service life of the gear 140 and the pump body. This structure achieves adaptive switching of clearance between high and low pressure conditions through a single elastic element, avoiding the complex hydraulic compensation mechanism of traditional floating side plates and overcoming the shortcomings of fixed clearance designs that cannot simultaneously achieve high and low pressure efficiency, greatly simplifying the internal structure of the pump body and reducing manufacturing costs.

[0040] In this application, the one-way valve 220 includes a valve body 221, within which a valve cavity is provided. A valve core 224 and a reset elastic element 225 are installed within the valve cavity. The valve body 221 has an inlet 222 and an outlet 223 communicating with the valve cavity. The valve core 224, supported by the reset elastic element 225, opens or closes the inlet 222. The valve core 224 has a corresponding sealing element 226 that can close the inlet 222. A control head 227 is provided on the valve core 224. When the one-way valve 220 is closed, the control head 227 is located within the inlet 222. The control head 227 is a frustum-shaped structure, wider at the bottom and narrower at the top, with its lower part connected to the valve core 224. The inlet 222 is cylindrical.

[0041] Specifically, the valve core 224 includes a shell and an inner core. The inner core includes an assembly part, which is fixed to the shell by a locking block. The control head 227 is connected to the assembly part via a neck, the outer diameter of which is smaller than that of the control head 227. A seal 226 is assembled on the neck. The valve core 224 has a prismatic structure, and the space inside the valve cavity for assembling the valve core 224 is cylindrical. A gap for oil flow is formed between the side of the prism and the inner wall of the valve cavity. The seal 226 protrudes from the end face of the valve core 224. The valve core 224 has several protrusions 228 on the end face where the seal 226 is assembled, and the protrusion height of the seal 226 is greater than the height of the protrusions 228.

[0042] The check valve 220 achieves pressure maintenance by sealing the inlet 222 with the seal 226. The higher the hydraulic pressure returning to the valve chamber, the greater the reverse pressure on the seal 226, resulting in a better sealing effect and superior pressure maintenance performance. This design effectively prevents oil leakage under high pressure, ensuring that the check valve 220 can stably maintain the predetermined pressure under various operating conditions, thus improving the reliability and stability of the system. The valve core 224 adopts a prismatic structure, forming a gap between its side and the inner wall of the valve chamber for oil flow. This design not only simplifies the structure but also improves the oil flow efficiency and reduces resistance and energy loss during oil flow. The protrusion 228 provides good protection for the seal 226. When the hydraulic pressure is too high, the protrusion 228 will bear the pressure before the seal 226, preventing the seal 226 from being damaged by overpressure. Under the protection of the protrusion 228, the rubber seal 226 can maintain good sealing performance for a long time, thereby significantly extending the service life of the check valve 220 and reducing equipment maintenance costs and replacement frequency.

[0043] Furthermore, the first pressurizing chamber 200 and the second pressurizing chamber 210 are arranged horizontally symmetrically about the pressure regulating groove; the first flow channel 101 and the second flow channel 102 are arranged horizontally symmetrically about the gear set. The main flow channel 103 has a first oil groove 111 on one side near the gear meshing point and a second oil groove 131 on the other side. The first oil groove 111 is located on the upper cover 110, and the second oil groove 131 is located on the lower shell 130. The upper cover 110 and the lower shell 130 are provided with mounting grooves for installing the elastic ring 150, and a third oil groove 112 is provided on the side of the mounting groove. The symmetrical layout and layered design of the flow channels and oil grooves greatly optimizes the uniformity of oil flow and anti-contamination ability in the pump: the first oil groove 111 and the second oil groove 131 are respectively located on the upper cover 110 and the lower shell 130, and form a connected loop through the third oil groove 112 on the side of the mounting groove, so that the oil distribution in the meshing area of ​​the gear 140 is more uniform and the frictional heat accumulation on the end face of the gear 140 is reduced.

[0044] The scope of protection of this utility model includes, but is not limited to, the above embodiments. The scope of protection of this utility model is defined by the claims. Any substitutions, modifications, or improvements to this technology that are easily conceived by those skilled in the art shall fall within the scope of protection of this utility model.

Claims

1. A gear pump, comprising a housing (100), wherein a gear set and a flow channel are disposed within the housing (100); the gear set includes a pair of meshing gears (140), one of which is connected to a motor; the flow channel is divided into a first flow channel (101) and a second flow channel (102) with the meshing point of the gear set as the boundary; characterized in that, The housing (100) includes an upper cover (110), a middle plate (120) and a lower shell (130). The upper cover (110), the middle plate (120) and the lower shell (130) cooperate to form an inner cavity for installing the gear set. The thickness of the middle plate (120) is equal to the thickness of the gear (140). An elastic ring (150) is provided on the inner wall of the upper cover (110) and the lower shell (130) corresponding to the end face of the gear (140). The elastic ring (150) abuts against the end face of the gear (140). When the elastic ring (150) is compressed to the limit under the action of oil pressure, the inner wall of the upper cover (110) and the lower shell (130) abuts against the end face of the gear (140).

2. A gear pump according to claim 1, characterized in that, Both the first flow channel (101) and the second flow channel (102) include a main flow channel (103); the main flow channel (103) is provided with an oil inlet channel (105) and an oil outlet channel (104), and the oil enters the gear pump from the oil inlet channel (105). The oil inlet channel (105) is equipped with a flow restrictor valve (106) that allows only one-way oil inflow; the oil outlet channel (104) of the first flow channel (101) is connected to a first pressurization chamber (200), and the first pressurization chamber (200) is provided with a... The first oil outlet (202) and the oil outlet (104) of the second flow channel (102) are connected to the second pressurizing chamber (210). The second pressurizing chamber (210) is provided with a second oil outlet. Both the first pressurizing chamber (200) and the second pressurizing chamber (210) are equipped with a one-way valve (220) that can only discharge oil in one direction. The first pressurizing chamber (200) and the second pressurizing chamber (210) are connected by a pressure regulating groove. The pressure regulating groove is equipped with a movable reciprocating valve (230).

3. A gear pump according to claim 2, characterized in that, The one-way valve (220) includes a valve body (221), a valve cavity is provided inside the valve body (221), and a valve core (224) and a reset elastic element (225) are installed inside the valve cavity; the valve body (221) is provided with an inlet (222) and an outlet (223) that communicate with the valve cavity; the valve core (224) opens or closes the inlet (222) with the support of the reset elastic element (225); the valve core (224) is provided with a corresponding inlet (222) and a sealing element (226) that can close the inlet (222).

4. A gear pump according to claim 3, characterized in that, A control head (227) is provided on the valve core (224). When the check valve (220) is closed, the control head (227) is located inside the inlet (222). The control head (227) is a frustum shape with a larger bottom and a smaller top. The lower part of the control head (227) is connected to the valve core (224). The inlet (222) is cylindrical.

5. A gear pump according to claim 4, characterized in that, The valve core (224) includes a shell and an inner core. The inner core includes an assembly part, which is fixed to the shell by a locking block. The control head (227) is connected to the assembly part through a neck. The outer diameter of the neck is smaller than that of the control head (227). The seal (226) is assembled on the neck.

6. A gear pump according to claim 3, characterized in that, The valve core (224) has a prismatic structure. The space inside the valve cavity for assembling the valve core (224) is cylindrical. A gap for oil flow is formed between the side of the prismatic core and the inner wall of the valve cavity.

7. A gear pump according to claim 3, characterized in that, The seal (226) protrudes from the end face of the valve core (224). The valve core (224) has several protrusions (228) on the end face where the seal (226) is assembled. The protrusion height of the seal (226) is greater than the height of the protrusions (228).

8. A gear pump according to claim 2, characterized in that, The first pressurizing chamber (200) and the second pressurizing chamber (210) are arranged horizontally symmetrically about the pressure regulating groove; the first flow channel (101) and the second flow channel (102) are arranged horizontally symmetrically about the gear set.

9. A gear pump according to claim 2, characterized in that, The main channel (103) has a first oil groove (111) on one side near the meshing point of the gear set and a second oil groove (131) on the other side. The first oil groove (111) is located on the upper cover (110) and the second oil groove (131) is located on the lower shell (130). The upper cover (110) and the lower shell (130) are provided with mounting grooves for installing elastic rings (150), and a third oil groove (112) is provided on the side of the mounting groove.

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