Axially compensated micro gear pump

Abstract

The utility model discloses an axial compensation formula miniature gear pump, it includes, pump shell, sealing assembly and anti -backflow subassembly, the inside of pump shell is equipped with first gear and second gear, and first gear and second gear interlock, the one side fixedly connected with sealing element of sealing cover, the inside fixedly connected with spring of first annular groove, the one side of anti -backflow spare is provided with low pressure groove, the other side of anti -backflow spare is provided with high pressure groove, through above -mentioned structure, through the pre -tightening elastic force effect of spring in sealing assembly, continuously push sealing element axial compression anti -backflow subassembly, can compensate the axial gap of gear pair because of long -term wear, promote the dynamic sealing performance between high low pressure chamber, avoid the oil leakage caused by the gap increase, prolong the service life of gear pump, and anti -backflow subassembly adopts high low pressure groove differentiation volume structure, effectively suppresses high pressure oil liquid through gear end face gap to the oil inlet reverse backflow.

Description

Technical Field

[0001] This utility model relates to the field of gear pump technology, and in particular to an axially compensated micro gear pump. Background Technology

[0002] Miniature gear pumps, with their advantages of compact structure, few moving parts, and small output flow pulsation, have become core components of microscale fluid systems. These pumps achieve quantitative fluid delivery by rotating a pair of meshing gears to create volume changes within a sealed cavity. The key to their performance lies in controlling the gear meshing clearance, especially the axial clearance (the gap between the gear end face and the pump body side plate), which directly affects the pump's volumetric efficiency, leakage, and service life. For example, a Chinese patent discloses an axial floating compensation side plate for gear pumps, with application number 202420656356.X. It uses the elastic force provided by several elastic elements for axial compensation, ensuring that the gear end face can bear force evenly, which effectively avoids the problem of skewness that easily occurs in floating side plates in external gear pumps. However, when the system pressure is too high, leakage will occur at the gear end face gap. The reverse leakage of high-pressure oil along the end face gap not only leads to a decrease in volumetric efficiency. Utility Model Content

[0003] The purpose of this invention is to at least solve one of the technical problems existing in the prior art, and to provide an axially compensated micro gear pump. Through the pre-tightening force of the spring in the sealing assembly, the sealing element is continuously pushed to axially press against the anti-backflow assembly, which can compensate for the axial clearance caused by long-term wear of the gear pair, improve the dynamic sealing performance between the high and low pressure chambers, avoid oil leakage caused by increased clearance, and extend the service life of the gear pump. The anti-backflow assembly adopts a differentiated volume structure of high and low pressure grooves, which effectively inhibits the backflow of high pressure oil to the oil inlet through the gear end face gap.

[0004] This utility model also provides a micro gear pump with the above-mentioned axial compensation, including: a pump housing, a sealing assembly, and an anti-backflow assembly. The pump housing has a first gear and a second gear inside, and the first gear and the second gear mesh with each other. An output rod is fixedly connected inside the first gear, and a fixed rod is fixedly connected inside the second gear. The sealing assembly includes a sealing cover, and a sealing element is fixedly connected to one side of the sealing cover. A first annular groove is opened inside the sealing element, and a spring is fixedly connected inside the first annular groove. The anti-backflow assembly includes an anti-backflow element, and a second annular groove is opened inside the anti-backflow element. A low-pressure groove is opened on one side of the anti-backflow element, and a high-pressure groove is opened on the other side of the anti-backflow element. An arc-shaped baffle is formed between the anti-backflow element and the high-pressure groove. The spring is inserted into the second annular groove. Both the sealing element and the second annular groove have holes for the output rod and the fixed rod to move. There are two anti-backflow assemblies, located on both sides of the first gear and the second gear. The sealing element achieves axial dynamic compensation through spring preload, which can automatically adapt to changes in axial clearance caused by gear wear or thermal expansion and contraction, and maintain the stability of sealing performance.

[0005] According to the axially compensated micro gear pump of this utility model, the volume of the low-pressure tank is smaller than that of the high-pressure tank, which creates a pressure gradient difference and enhances the anti-backflow effect.

[0006] According to the axially compensated micro gear pump of this utility model, the pump housing has an oil outlet and an oil inlet on both sides, the low-pressure groove is located on one side of the oil inlet, and the high-pressure groove is located on the one side of the oil outlet.

[0007] According to the axially compensated micro gear pump of this utility model, the pump casing and the sealing cover are both provided with fixing holes and are fixedly connected by bolts. The pump casing and the sealing cover connected by bolts are easy to disassemble, and the internal components can be quickly replaced, shortening the maintenance cycle.

[0008] According to the axially compensated micro gear pump of this utility model, the bottom of the pump housing is fixedly connected to a support foot, and the support foot is provided with a fixing hole.

[0009] According to the axially compensated micro gear pump of this utility model, the contact surface between the pump casing and the sealing cover is provided with a sealing sleeve, which reduces the risk of leakage.

[0010] According to the axially compensated micro gear pump of this utility model, both the seal and the anti-backflow component are corrosion resistant.

[0011] According to the axially compensated micro gear pump of this utility model, the first gear and the fixed rod are both fixedly connected to the two sides of the limiting shaft, and are in contact with one side of the anti-backflow component. The limiting shafts on both sides of the gear restrict axial displacement and prevent the gear from directly contacting and wearing with the anti-backflow component.

[0012] Beneficial effects: This utility model, by setting up structures such as an oil sealing component and an anti-backflow component, uses the pre-tightening force of the spring in the sealing component to continuously push the seal to axially press the anti-backflow component, which can compensate for the axial clearance caused by long-term wear of the gear pair, improve the dynamic sealing performance between the high and low pressure chambers, avoid oil leakage caused by increased clearance, and extend the service life of the gear pump. The anti-backflow component adopts a differentiated volume structure of high and low pressure grooves, which effectively inhibits the backflow of high pressure oil to the oil inlet through the gear end face gap. Attached Figure Description

[0013] The present invention will be further described below with reference to the accompanying drawings and embodiments; Figure 1 This is a structural diagram of the entire utility model; Figure 2 This is a structural diagram of the sealing assembly of this utility model; Figure 3 This is a structural diagram showing the internal connection relationship of the pump casing of this utility model; Figure 4 This is a structural diagram showing the connection relationship between the sealing element and the anti-backflow assembly of this utility model; Figure 5 This is a structural diagram of the anti-backflow component of this utility model.

[0014] Legend: 1. Pump casing; 2. Sealing assembly; 3. Backflow prevention assembly; 101. Output rod; 102. Support foot; 103. First gear; 104. Second gear; 201. Sealing cover; 202. Seal; 203. First annular groove; 204. Spring; 301. Anti-backflow component; 302. Second annular groove; 303. Low-pressure groove; 304. High-pressure groove; 1041, fixed rod; 3041, arc-shaped baffle. Detailed Implementation

[0015] This section will describe in detail the specific embodiments of the present utility model. The preferred embodiments of the present utility model are shown in the accompanying drawings. The purpose of the drawings is to supplement the textual description with graphics, so that people can intuitively and vividly understand each technical feature and the overall technical solution of the present utility model, but they should not be construed as limiting the scope of protection of the present utility model.

[0016] Reference Figure 1-5The axially compensated micro gear pump of this utility model includes: a pump housing 1, a sealing assembly 2, and an anti-backflow assembly 3. The pump housing 1 is provided with a first gear 103 and a second gear 104 inside, and the first gear 103 and the second gear 104 mesh with each other. An output rod 101 is fixedly connected inside the first gear 103, and a fixing rod 1041 is fixedly connected inside the second gear 104. An oil outlet and an oil inlet are opened on both sides of the pump housing 1. A support foot 102 is fixedly connected to the bottom of the pump housing 1, and the support foot 102 is provided with a fixing hole.

[0017] Specifically, a first gear 103 and a second gear 104 are symmetrically installed inside the pump housing 1. The two gears form a gear pair through tooth surface meshing. The output rod 101 is fixedly connected to the center hole of the first gear 103 through a keyway or interference fit. One end of the output rod 101 extends to the outside of the pump housing 1 and is connected to the drive motor. The fixing rod 1041 is fixedly connected to the center hole of the second gear 104. The two ends of the fixing rod 1041 are fixed to the inner wall of the pump housing 1 through bearings or limiting structures to ensure that the second gear 104 follows the passive rotation of the first gear 103. An oil inlet (low-pressure side) and an oil outlet (high-pressure side) are opened on both sides of the pump housing 1, respectively. A support foot 102 is welded or integrally formed at the bottom, and a fixing hole is provided on the support foot 102.

[0018] The sealing assembly 2 includes a sealing cover 201, a sealing element 202 is fixedly connected to one side of the sealing cover 201, a first annular groove 203 is opened inside the sealing element 202, a spring 204 is fixedly connected inside the first annular groove 203, a fixing hole is opened inside the pump housing 1 and the sealing cover 201, and they are fixedly connected by bolts. A sealing sleeve is provided on the contact surface between the pump housing 1 and the sealing cover 201.

[0019] Specifically, the sealing cover 201 is fixedly connected to the end face of the pump housing 1 by bolts, and a sealing sleeve is provided on the contact surface between the two. A first annular groove 203 is opened on the inner side of the sealing element 202, and a spring 204 (preferably an oil-resistant disc spring or a helical spring) is installed in the groove. The sealing element 202 is fixed to the inner side of the sealing cover 201 by screws or buckles.

[0020] The anti-backflow assembly 3 includes an anti-backflow component 301. A second annular groove 302 is formed inside the anti-backflow component 301. A low-pressure groove 303 is formed on one side of the anti-backflow component 301, and a high-pressure groove 304 is formed on the other side. An arc-shaped baffle 3041 is formed between the anti-backflow component 301 and the high-pressure groove 304. A spring 204 is inserted into the second annular groove 302. Both the sealing component 202 and the second annular groove 302 are provided with outlet rod 101 and fixing rod 1. The 041 movable hole has two anti-backflow components 3, which are located on both sides of the first gear 103 and the second gear 104. The volume of the low-pressure groove 303 is smaller than that of the high-pressure groove 304. The low-pressure groove 303 is located on one side of the oil inlet, and the high-pressure groove 304 is located on one side of the oil outlet. Both the seal 202 and the anti-backflow component 301 are corrosion resistant. The first gear 103 and the fixed rod 1041 are fixedly connected to the limit shaft on both sides and are in contact with one side of the anti-backflow component 301.

[0021] Specifically, two sets of anti-backflow components 301 are located on both sides of the first gear 103 and the second gear 104, respectively. The anti-backflow component 301 is made of corrosion-resistant engineering plastic or metal. A second annular groove 302 is opened inside it. The free end of the spring 204 is inserted into the groove to form an axial limit. The anti-backflow component 301 is machined with a low-pressure groove 303 and a high-pressure groove 304 on the side facing the gear. The low-pressure groove 303 has a smaller volume and is connected to the oil inlet. The high-pressure groove 304 has a larger volume and is connected to the oil outlet. The anti-backflow component 301 and the high-pressure groove 304 form an arc-shaped baffle 3041.

[0022] Working principle: When the pump housing 1 and the sealing cover 201 are sealed, the spring 204 in the sealing assembly 2 pushes the sealing element 202 axially to press the anti-backflow element 301 through its pre-tightening elastic force. This forces the two sets of anti-backflow elements 301 to tightly fit the end faces of the first gear 103 and the second gear 104 respectively, compensating for the axial clearance caused by wear of the gear pair in real time, ensuring the dynamic sealing between the high and low pressure chambers. The drive motor drives the output rod 101 to rotate, and the first gear 103 and the second gear 104 mesh and rotate, drawing in oil from the oil inlet and pressurizing it through the change in the inter-tooth volume, and finally discharging it from the oil outlet. The oil squeezed by the gears migrates from the low-pressure tank 303 to the high-pressure tank 304. Since the volume of the high-pressure tank 304 is larger than that of the low-pressure tank 303, a pressure gradient is formed between the two tanks, thereby effectively suppressing the backflow of high-pressure oil to the oil inlet through the gap between the gear end faces.

[0023] The embodiments of the present utility model have been described in detail above with reference to the accompanying drawings. However, the present utility model is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present utility model.

Claims

1. An axially compensated miniature gear pump, characterized in that, include: The pump housing (1), sealing assembly (2), and anti-backflow assembly (3) are provided. The pump housing (1) is provided with a first gear (103) and a second gear (104) inside, and the first gear (103) and the second gear (104) mesh with each other. An output rod (101) is fixedly connected inside the first gear (103), and a fixing rod (1041) is fixedly connected inside the second gear (104). The sealing assembly (2) includes a sealing cover (201), and a sealing element (202) is fixedly connected to one side of the sealing cover (201). A first annular groove (203) is opened inside the sealing element (202), and a spring (204) is fixedly connected inside the first annular groove (203). The anti-backflow assembly (3) includes an anti-backflow component (301), the interior of which is provided with a second annular groove (302), a low-pressure groove (303) on one side of the anti-backflow component (301), and a high-pressure groove (304) on the other side of the anti-backflow component (301). An arc-shaped baffle (3041) is formed between the anti-backflow component (301) and the high-pressure groove (304). The spring (204) is inserted into the interior of the second annular groove (302). The sealing component (202) and the second annular groove (302) are both provided with holes for the output rod (101) and the fixing rod (1041) to move. There are two anti-backflow assemblies (3), which are located on both sides of the first gear (103) and the second gear (104).

2. The axially compensated micro gear pump according to claim 1, characterized in that, The volume of the low-pressure tank (303) is smaller than that of the high-pressure tank (304).

3. The axially compensated micro gear pump according to claim 2, characterized in that, The pump casing (1) has an oil outlet and an oil inlet on both sides. The low-pressure groove (303) is located on one side of the oil inlet, and the high-pressure groove (304) is located on the one side of the oil outlet.

4. The axially compensated micro gear pump according to claim 1, characterized in that, The pump casing (1) and the sealing cover (201) are both provided with fixing holes and are fixedly connected by bolts.

5. The axially compensated micro gear pump according to claim 1, characterized in that, The bottom of the pump casing (1) is fixedly connected to a support foot (102), and the support foot (102) has a fixing hole.

6. The axially compensated micro gear pump according to claim 1, characterized in that, The contact surface between the pump casing (1) and the sealing cover (201) is provided with a sealing sleeve.

7. The axially compensated micro gear pump according to claim 1, characterized in that, Both the seal (202) and the anti-backflow component (301) are corrosion resistant.

8. The axially compensated micro gear pump according to claim 1, characterized in that, The first gear (103) and the fixed rod (1041) are both fixedly connected to the limit shafts on both sides and are in contact with one side of the anti-backflow component (301).

Images