Internal gear pump capable of running more stably

Abstract

The invention relates to an internal gear pump capable of running more stably. The internal gear pump comprises a shell provided with a cavity and a high-pressure cavity. The cavity is rotationally provided with a gear and a gear ring, a crescent plate is arranged between the gear and the gear ring, and the cavity is provided with an inner circumferential wall and an axial wall which are matched with the gear ring. And the oil guide device between the high-pressure cavity and the cavity comprises an oil guide-in path, a movable push rod and an elastic component. An oil inlet of the introduction oil way is connected with the high-pressure cavity, and an oil outlet is formed in the inner circumferential wall of the cavity. An elastic component is arranged between the movable push rod and the shell, an oil conveying channel is formed in the movable push rod, and a first opening and a second opening are formed in the two ends of the movable push rod respectively. The lead-in oil way comprises a first section and a second section which are perpendicular, the movable push rod is movably inserted into the first section, the oil conveying channel is connected with the second section through a second opening, and the inner edge of a first section connecting opening is matched with the second opening for shielding. According to the gear pump, the pressure of introduced oil can be adjusted in time, operation is more stable, and the stability and adaptability under different working conditions are improved.

Description

Technical Field

[0001] The invention relates to an internal gear pump which operates more stably. Background Art

[0002] An internal gear pump (CN116608121A) is disclosed in a Chinese invention patent application. Its features include an oil inlet circuit connected to the oil pressure chamber (i.e., high-pressure chamber) provided on the inner wall of the housing (i.e., the inner wall of the cavity). The oil inlet circuit can introduce the high-pressure medium in the oil pressure chamber into the inner wall of the housing. The medium introduced by the oil inlet circuit acts on the outer contour of the gear ring and applies a thrust from the outside to the inside to the gear ring. The pressure offsets a part of the thrust from the inside to the outside exerted by the high-pressure medium in the oil pressure chamber on the inner gear ring, which can reduce the amount of displacement of the inner gear ring toward the housing when rotating at high speed, thereby reducing the noise generated when the inner gear ring rotates at high speed. However, in actual implementation, it is found that since the oil inlet circuit is composed of multiple sections, has a corner, and also has a narrow section, there are certain technical difficulties in how to integrally process the oil inlet circuit on a component.

[0003] In addition, in the above patent application scheme, since the aperture size of the second section of the oil introduction circuit is fixed, the oil pressure introduced into the oil introduction circuit changes with the change of the oil pressure in the oil pressure chamber, and there is a certain hysteresis. When the load and operating speed of the gear pump change suddenly, it may cause the inner ring gear to deviate more, resulting in increased friction with the housing and crescent body, increased noise and accelerated wear of components, and may also cause local pressure to be too high, affecting the stable operation of the inner ring gear. Summary of the invention

[0004] In order to overcome the defects of the above-mentioned prior art, the present invention provides an internal gear pump with more stable operation, which can timely adjust the introduced oil pressure and improve the stability and adaptability of the gear pump under different working conditions.

[0005] The present invention provides an internal meshing gear pump with more stable operation, comprising a shell, the shell comprising a cavity, a high-pressure cavity and a low-pressure cavity connected to the cavity, a gear and a gear ring are rotatably arranged in the cavity, the high-pressure cavity is arranged at the axial ends of the gear ring, a crescent plate is arranged between the gear and the gear ring, the crescent plate circumferentially divides the gap between the gear and the gear ring into a low-pressure area connected to the low-pressure cavity, a high-pressure area connected to the high-pressure cavity, and a boost area connected between the low-pressure area and the high-pressure area, the cavity comprises an inner circumferential wall that cooperates with the outer circumferential wall of the gear ring and two axial walls that can limit the axial position of the gear ring, an oil introduction device is arranged between the high-pressure cavity and the cavity, the oil introduction device comprises an oil introduction circuit arranged on the shell, the oil inlet of the oil introduction circuit is connected to the high-pressure cavity, the oil outlet of the oil introduction circuit is arranged at the inner circumferential wall of the cavity, in particular, at a position corresponding to the high-pressure area formed between the gear and the gear ring, The oil device includes a movable push rod and an elastic component. The movable push rod is movably arranged at the oil outlet of the oil introduction circuit. An elastic component is abutted between the movable push rod and the shell. The elastic component drives one end of the movable push rod to elastically abut the outer peripheral wall of the gear ring and slides in contact with the outer peripheral wall of the gear ring. An oil delivery channel is arranged in the movable push rod. A first opening connected to the oil delivery channel is arranged at one end of the movable push rod, and a second opening connected to the oil delivery channel is arranged on the peripheral side of the other end of the movable push rod. The oil introduced into the oil circuit is introduced into the cavity along the direction of the second opening, the oil delivery channel and the first opening. The oil introduction circuit includes a first section and a second section which are perpendicular to each other. The movable push rod and the first section form a movable plug-in fit. The oil delivery channel of the movable push rod is connected to the second section through the second opening at the other end thereof. The first section has a connecting port that is matched with the second section, and the inner edge of the connecting port is matched with the second opening to block.

[0006] Since there is a certain gap between the gear ring and the inner wall of the cavity, when the gear ring is affected by the oil pressure and produces a lateral displacement, the movable push rod can be displaced accordingly, and the relative position between the inner edge of the connecting port and the second opening will change accordingly, which can change the size of the connecting port diameter between the second opening and the second section of the inlet oil circuit. Therefore, the introduced oil pressure can be adjusted in time to make the introduced oil pressure counteract the offset thrust of the gear ring, thereby improving the stability and adaptability of the gear pump under different working conditions, and solving the problem of pressure imbalance in the fixed-diameter inlet oil circuit in the prior art when the working conditions change rapidly.

[0007] Furthermore, the first section has a flared opening connected to the cavity, one end of the movable push rod includes an abutment portion, one end of the flared opening is movably connected to the abutment portion of the movable push rod, the other end of the flared opening has an annular step surface, the elastic member is a spring sleeved on the movable push rod, the spring is located at the flared opening, the two ends of the spring respectively abut and cooperate with the abutment portion and the annular step surface, the setting of the abutment portion can improve the contact effect with the gear ring, the setting of the flared opening can be used to accommodate the abutment portion, only a simple hole needs to be opened on the inner circumferential wall of the cavity, and then the spring and the movable push rod are installed in turn to complete the processing and assembly. Restricted by the gear ring, the movable push rod will not fall out of the oil introduction circuit, the overall structure is simple, and assembly is convenient.

[0008] Furthermore, a third opening for connecting the oil delivery channel and the flare is provided on the peripheral side of one end of the movable push rod. The provision of the third opening is conducive to ensuring the pressure balance between the flare and the oil delivery channel and reducing the resistance when the movable push rod is displaced.

[0009] Furthermore, the abutment portion has an arc-shaped concave surface that contacts and cooperates with the outer peripheral wall of the gear ring, and the first opening is arranged on the arc-shaped concave surface, which can further improve the contact and cooperation effect between the abutment portion and the outer peripheral wall of the gear ring. The introduced oil flows out from the first opening and penetrates between the abutment portion and the gear ring, reducing wear between the components.

[0010] Furthermore, the second opening is a long strip-shaped through slot, the directions of both ends of which correspond to the length direction of the movable push rod, so as to facilitate the processing of the second opening and improve the oil pressure regulation effect.

[0011] Furthermore, there are multiple second openings, and the multiple second openings are evenly distributed along the circumference of the movable push rod, thereby improving the oil inlet effect relative to the second openings.

[0012] Furthermore, the shell includes a first part and a second part which are spliced ​​together, the inner peripheral wall of the cavity and one of the axial walls and the oil introduction device are all arranged on the first part, the other axial wall of the cavity is arranged on the second part, the oil introduction circuit includes a third section which is parallel to the first section and perpendicular to the second section, one end of the third section is connected to the high-pressure cavity, the other end of the third section is connected to one end of the second section, and the other end of the second section is provided with a process port on the splicing surface of the first section, and a plug is provided at the process port. During processing, the third section can be processed from the inner side of the high-pressure cavity, and then the second section can be processed from the splicing surface of the first section to make it connected with the first section and the second section. It is only necessary to open a number of straight holes on the first part of the shell to process the oil introduction circuit, which is convenient to process, and this structure has good sealing performance and is not prone to oil leakage risks.

[0013] Furthermore, a shallow groove is provided on the joint surface of the first part, the process port is provided at the bottom of the shallow groove, the plug is a sealing gasket embedded in the shallow groove, and the sealing gasket is pressed between the first part and the second part, which can further improve the sealing effect at the process port and prevent oil leakage. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 is a cross-sectional view of an embodiment of the present invention; Figure 2 for Figure 1 A partial enlarged view of Figure 3 This is a schematic diagram of the distribution of pressure intervals in an embodiment of the present invention; Figure 4 The figure is a schematic diagram of the structure of a movable push rod according to an embodiment of the present invention. DETAILED DESCRIPTION

[0015] An internal gear pump with more stable operation according to an embodiment of the present invention, such as Figure 1-4 As shown, The invention comprises a shell, the shell comprises a cavity 101, a high-pressure cavity 102 connected to the cavity 101, and a low-pressure cavity 103. A gear 2 and a gear ring 3 are rotatably arranged in the cavity 101. The high-pressure cavity 102 is arranged at both axial ends of the gear ring 3. A crescent plate 4 is arranged between the gear 2 and the gear ring 3. The crescent plate 4 circumferentially divides the gap between the gear 2 and the gear ring 3 into a low-pressure zone connected to the low-pressure cavity 103, a high-pressure zone connected to the high-pressure cavity 102, and a boost zone connected between the low-pressure zone and the high-pressure zone. Specifically, the connection line between the two sides of the crescent plate 4 and the axis of the gear 2 and the connection line between the axis and the meshing position of the gear 2 and the gear ring 3 are used as boundaries (i.e., Figure 3 The gap is divided into three areas, the low-pressure area connected to the low-pressure chamber 103, the high-pressure area connected to the high-pressure chamber 102, and the boost area in the middle. The cavity 101 includes an inner circumferential wall 1011 that cooperates with the outer circumferential wall of the gear ring 3 and two axial walls 1012 that can limit the axial direction of the gear ring 3. An oil introduction device is arranged between the high-pressure chamber 102 and the cavity 101, and the oil introduction device includes an oil introduction circuit arranged on the shell, the oil inlet of the oil introduction circuit is connected to the high-pressure chamber 102, and the oil outlet of the oil introduction circuit is arranged at the inner circumferential wall of the cavity 101, in particular, at a position corresponding to the high-pressure area formed between the gear 2 and the gear ring 3.

[0016] The oil introduction device includes a movable push rod 51 and an elastic member 52. The movable push rod 51 is movably arranged at the oil outlet of the oil introduction passage. The elastic member 52 is abutted between the movable push rod 51 and the housing. The elastic member 52 drives one end of the movable push rod 51 to elastically abut against the outer peripheral wall of the gear ring 3 and slides in contact with the outer peripheral wall of the gear ring 3. An oil delivery channel is arranged in the movable push rod 51. One end of the movable push rod 51 is provided with a first opening 511 connected to the oil delivery channel. The peripheral side of the other end of the movable push rod 51 is provided with a first opening 511 connected to the oil delivery channel. The second opening 512, the oil in the oil circuit is introduced into the cavity 101 along the direction of the second opening 512, the oil delivery channel and the first opening 511, the oil introduction circuit includes a first section 531 and a second section 532 which are perpendicular to each other, the movable push rod 51 and the first section 531 form a movable plug-in fit, the oil delivery channel of the movable push rod 51 is connected with the second section 532 through the second opening 512 at the other end thereof, the first section 531 has a connecting port which is connected to the second section 532, and the inner edge 5311 of the connecting port is matched with the second opening 512 to block.

[0017] Since there is a certain gap between the gear ring 3 and the inner circumferential wall of the cavity 101, when the gear ring 3 is affected by the oil pressure and produces a lateral displacement, the movable push rod 51 can be displaced accordingly, and the relative position between the inner edge 5311 of the connecting port and the second opening 512 changes accordingly, which can change the size of the connecting aperture between the second opening 512 and the second section 532 of the inlet oil circuit, thereby being able to timely adjust the introduced oil pressure so that the introduced oil pressure can counteract the offset thrust of the gear ring 3, thereby improving the stability and adaptability of the gear 2 pump under different working conditions, and solving the problem of pressure imbalance in the fixed-diameter inlet oil circuit in the prior art when the working conditions change rapidly.

[0018] Specifically, when the movable push rod 51 is pushed by the ring gear 3 to displace in the direction of extending into the first section 531, the inner edge 5311 of the connecting port reduces the blocking of the second opening 512, and the pressure of the introduced oil increases. The oil pressure and the elastic force of the elastic component 52 act together on the ring gear 3 to counteract the displacement of the ring gear 3; when the displacement thrust of the ring gear 3 decreases, the movable push rod 51 displaces toward the cavity, the inner edge 5311 increases the blocking of the second opening 512, and the pressure of the introduced oil decreases, thereby achieving the effect of balancing the pressure.

[0019] The first section 531 has a flared opening 5312 connected to the cavity 101, and one end of the movable push rod 51 includes an abutment 513. One end of the flared opening 5312 is movably connected to the abutment 513 of the movable push rod 51, and the other end of the flared opening 5312 has an annular step surface. The elastic member 52 is a spring sleeved on the movable push rod 51, and the spring is located at the flared opening 5312. The two ends of the spring are respectively abutted and matched with the abutment 513 and the annular step surface. The setting of the abutment 513 can improve the contact effect with the gear ring 3. The setting of the flared opening 5312 can be used to accommodate the abutment 513. It only needs to simply open a hole in the inner circumferential wall of the cavity 101, and then install the spring and the movable push rod 51 in sequence to complete the processing and assembly. Limited by the gear ring 3, the movable push rod 51 will not fall out of the introduced oil circuit. The overall structure is simple and easy to assemble.

[0020] A third opening 514 for connecting the oil delivery channel and the expansion port 5312 is provided at one end of the movable push rod 51 . The third opening 514 is provided to ensure pressure balance between the expansion port 5312 and the oil delivery channel and reduce resistance when the movable push rod 51 is displaced.

[0021] The abutment portion 513 has an arc-shaped concave surface 5131 that contacts and cooperates with the outer peripheral wall of the ring gear 3. The first opening 511 is arranged on the arc-shaped concave surface 5131, which can further improve the contact and cooperation effect between the abutment portion 513 and the outer peripheral wall of the ring gear 3. The introduced oil flows out from the first opening 511 and penetrates into between the abutment portion 513 and the ring gear 3, reducing the wear between the components.

[0022] The second opening 512 is a long strip through slot, and the directions of both ends thereof correspond to the length direction of the movable push rod 51 , which facilitates the processing of the second opening 512 and improves the oil pressure regulation effect.

[0023] There are multiple second openings 512 , and the multiple second openings 512 are evenly distributed along the circumference of the movable push rod 51 , so as to improve the oil inlet effect relative to the second openings 512 .

[0024] The third opening 514 preferably adopts the same structure as the second opening 512 , and only the configuration position is different, which can reduce the processing cost of the third opening 514 .

[0025] The shell includes a first part 11 and a second part 12 which are spliced ​​together. The inner circumferential wall of the cavity 101 and one of the axial walls 1012 and the oil introduction device are all arranged on the first part 11. The other axial wall 1012 of the cavity 101 is arranged on the second part 12. The oil introduction circuit includes a third section 533 which is parallel to the first section 531 and perpendicular to the second section 532. One end of the third section 533 is connected to the high-pressure chamber 102, and the other end of the third section 533 is connected to one end of the second section 532. The other end of the second section 532 is provided with a process port on the splicing surface of the first part 11, and a plug 6 is provided at the process port. During processing, the third section 533 can be processed from the inner side of the high-pressure chamber 102, and then the second section 532 can be processed from the joint surface of the first part 11 to make it connected with the first section 531 and the second section 532. It is only necessary to open a number of straight holes on the first part 11 of the shell to process the oil introduction path. The processing is relatively convenient, and this structure has good sealing performance and is not prone to oil leakage risks.

[0026] A shallow groove is arranged on the joint surface of the first part 11, and the process port is arranged at the bottom of the shallow groove. The plug 6 is a sealing gasket embedded in the shallow groove. The sealing gasket is pressed between the first part 11 and the second part 12, which can further improve the sealing effect at the process port and prevent oil leakage.

[0027] The above embodiment is only one of the preferred specific embodiments of the present invention. Common changes and substitutions made by those skilled in the art within the scope of the technical solution of the present invention are all included in the protection scope of the present invention.

Claims

1. An internal gear pump with more stable operation, comprising a housing, the housing comprising a cavity, a high-pressure cavity connected to the cavity, a gear and a gear ring rotatably arranged in the cavity, the high-pressure cavity being arranged at both axial ends of the gear ring, a crescent plate being arranged between the gear and the gear ring, the cavity comprising an inner circumferential wall in contact with the outer circumferential wall of the gear ring and two axial walls capable of limiting the axial position of the gear ring, an oil introduction device being arranged between the high-pressure cavity and the cavity, the oil introduction device comprising an oil introduction path arranged on the housing, the oil inlet of the oil introduction path being connected to the high-pressure cavity, and the oil outlet of the oil introduction path being arranged at the inner circumferential wall of the cavity, characterized in that: The oil introduction device includes a movable push rod and an elastic component. The movable push rod is movably arranged at the oil outlet of the oil introduction circuit. An elastic component is abutted between the movable push rod and the shell. The elastic component drives one end of the movable push rod to abut against the outer peripheral wall of the gear ring. An oil delivery channel is arranged in the movable push rod. A first opening connected to the oil delivery channel is arranged at one end of the movable push rod, and a second opening connected to the oil delivery channel is arranged on the peripheral side of the other end of the movable push rod. The oil introduction circuit includes a first section and a second section that are perpendicular to each other. The movable push rod and the first section form a movable plug-in fit. The oil delivery channel of the movable push rod is connected to the second section through the second opening at the other end thereof. The first section has a connecting port that is matched with the second section, and the inner edge of the connecting port is matched with the second opening to block.

2. An internal gear pump with more stable operation according to claim 1, characterized in that: The first section has a flared opening connected to the cavity, one end of the movable push rod includes an abutment portion, one end of the flared opening is movably connected to the abutment portion of the movable push rod, the other end of the flared opening has an annular step surface, the elastic component is a spring sleeved on the movable push rod, the spring is located at the flared opening, and both ends of the spring are respectively abutted and matched with the abutment portion and the annular step surface.

3. An internal gear pump with more stable operation according to claim 2, characterized in that: A third opening for connecting the oil delivery channel and the expansion port is arranged on the peripheral side of one end of the movable push rod.

4. An internal gear pump with more stable operation according to claim 2, characterized in that: The abutting portion has an arc-shaped concave surface that contacts and cooperates with the outer peripheral wall of the gear ring, and the first opening is arranged on the arc-shaped concave surface.

5. An internal gear pump with more stable operation according to claim 1, characterized in that: The second opening is a long strip-shaped through slot, and the directions of both ends thereof correspond to the length direction of the movable push rod.

6. An internal gear pump with more stable operation according to claim 5, characterized in that: There are multiple second openings, and the multiple second openings are evenly distributed along the circumference of the movable push rod.

7. An internal gear pump with more stable operation according to claim 1, characterized in that: The shell includes a first part and a second part which are spliced ​​together. The inner circumferential wall of the cavity and one of the axial walls and the oil introduction device are all arranged on the first part. The other axial wall of the cavity is arranged on the second part. The oil introduction circuit includes a third section which is parallel to the first section and perpendicular to the second section. One end of the third section is connected to the high-pressure chamber, and the other end of the third section is connected to one end of the second section. The other end of the second section is provided with a process port on the splicing surface of the first part, and a plug is provided at the process port.

8. An internal gear pump with more stable operation according to claim 7, characterized in that: A shallow groove is arranged on the joint surface of the first part, the process port is arranged at the bottom of the shallow groove, the plug is a sealing gasket embedded in the shallow groove, and the sealing gasket is pressed tightly between the first part and the second part.

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