阅读说明：本技术 一种油泵 (Oil pump ) 是由 段井胜 孟秋英 朱尚旺 于 2021-01-19 设计创作，主要内容包括：本发明公开了一种油泵,包括泵体,所述泵体的左侧设有左端开口的圆形泵腔,所述泵体的左侧固定设有左端盖,所述圆形泵腔内转动连接有内齿圈,所述圆形泵腔内设有第一月牙板、第二月牙板、第三月牙板,所述左端盖和泵体之间转动连接有第一齿轮、第二齿轮、第三齿轮,所述第一齿轮的左端设有伸出左端盖的转轴；所述泵体的侧面设有P口和T口,所述圆形泵腔内形成第一吸油区和第一排油区、第二吸油区和第二排油区、第三吸油区和第三排油区；所述第一吸油区、第二吸油区、第三吸油区均与T口连通；所述第一排油区、第二排油区、第三排油区与P口连通；该油泵不仅结构简单,而且能够根据需要改变排量。(The invention discloses an oil pump which comprises a pump body, wherein a circular pump cavity with an opening at the left end is arranged at the left side of the pump body, a left end cover is fixedly arranged at the left side of the pump body, an inner gear ring is rotationally connected in the circular pump cavity, a first crescent plate, a second crescent plate and a third crescent plate are arranged in the circular pump cavity, a first gear, a second gear and a third gear are rotationally connected between the left end cover and the pump body, and a rotating shaft extending out of the left end cover is arranged at the left end of the first gear; a P port and a T port are formed in the side face of the pump body, and a first oil suction area and a first oil discharge area, a second oil suction area and a second oil discharge area, a third oil suction area and a third oil discharge area are formed in the circular pump cavity; the first oil absorption area, the second oil absorption area and the third oil absorption area are all communicated with the T port; the first oil discharge area, the second oil discharge area and the third oil discharge area are communicated with the port P; the oil pump is simple in structure and can change the displacement according to needs.)

1. An oil pump comprises a pump body and is characterized in that a circular pump cavity with an open left end is arranged on the left side of the pump body, a left end cover is fixedly arranged on the left side of the pump body at the left end opening of the circular pump cavity, an inner gear ring is rotationally connected in the circular pump cavity, three first crescent tooth plates, second crescent tooth plates and third crescent tooth plates which are located on the inner side of the inner gear ring are uniformly arranged in the circular pump cavity along the circumferential direction at intervals, a first gear is rotationally connected between the first crescent tooth plates and the third crescent tooth plates between the left end cover and the pump body, a second gear is rotationally connected between the first crescent tooth plates and the second crescent tooth plates, a third gear is rotationally connected between the second crescent tooth plates and the third crescent tooth plates, the first gear, the second gear and the third gear are all meshed with the inner gear ring, and a rotating shaft extending out of the left end cover is arranged at the left end of the first gear; a P port and a T port are formed in the side face of the pump body, a first oil suction area and a first oil discharge area are formed in the circular pump cavity on two sides of the first gear meshed with the inner gear ring, a second oil suction area and a second oil discharge area are formed on two sides of the second gear meshed with the inner gear ring, and a third oil suction area and a third oil discharge area are formed on two sides of the third gear meshed with the inner gear ring; the first oil absorption area, the second oil absorption area and the third oil absorption area are all communicated with the T port; the first oil discharge area is communicated with the port P through a first one-way valve, the second oil discharge area is communicated with the port P through a second one-way valve, and the third oil discharge area is communicated with the port P through a third one-way valve;

a first sliding plate is connected between the first crescent plate and the third crescent plate in the circular pump cavity in a sliding mode along the radial direction, when two ends of the first sliding plate are pressed on the first crescent plate and the third crescent plate respectively, oil flows from the first oil suction area to the first oil discharge area along with the rotation of the first gear and the inner gear ring, and when the first sliding plate leaves the first crescent plate and the third crescent plate, the first oil suction area and the first oil discharge area on two sides of the first gear are communicated; a second sliding plate is connected between the first crescent tooth plate and the second crescent tooth plate in the circular pump cavity in a sliding mode along the radial direction, when two ends of the first sliding plate are pressed on the first crescent tooth plate and the second crescent tooth plate respectively, oil flows from the second oil suction area to the second oil discharge area along with the rotation of the second gear and the inner gear ring, and when the second sliding plate leaves the first crescent tooth plate and the second crescent tooth plate, the second oil suction area and the second oil discharge area on two sides of the second gear are communicated; and when the third sliding plate leaves the second crescent plate and the third crescent plate, the third oil suction areas and the third oil discharge areas on two sides of the third gear are communicated.

2. The oil pump of claim 1, wherein the pump body has a first radially extending chute in facing relation to the first slide plate, a second radially extending chute in facing relation to the second slide plate, and a third radially extending chute in facing relation to the third slide plate; the first sliding plate is provided with a first shifting column extending into the first sliding groove, the second sliding plate is provided with a second shifting column extending into the second sliding groove, and the third sliding plate is provided with a third shifting column extending into the third sliding groove; and a variable control assembly for controlling the sliding of the first shifting column, the second shifting column and the third shifting column is arranged in the pump body.

3. The oil pump according to claim 2, wherein the variable control assembly comprises a rotating wheel, a rotating groove is formed in the right side surface of the pump body, the rotating groove and the circular pump cavity are in a coaxial position, the rotating wheel is rotatably connected in the rotating groove, and a sealing cover plate is fixedly arranged on the right side surface of the pump body at an opening of the rotating groove; first radial grooves, second radial grooves and third radial grooves communicated with the rotary grooves are uniformly arranged in the pump body at intervals along the circumferential direction of the rotary grooves; a first sliding block fixedly connected with the first shifting column is connected in the first radial groove in a sliding manner, a second sliding block fixedly connected with the second shifting column is connected in the second radial groove in a sliding manner, and a third sliding block fixedly connected with the third shifting column is connected in the third radial groove in a sliding manner; the far end of the first radial groove is provided with a first spring for forcing the first sliding block to be tightly pressed on the outer side of the rotating wheel, the far end of the second radial groove is provided with a second spring for forcing the second sliding block to be tightly pressed on the outer side of the rotating wheel, and the far end of the third radial groove is provided with a third spring for forcing the third sliding block to be tightly pressed on the outer side of the rotating wheel; a first cutting groove matched with the first sliding block, a second cutting groove matched with the second sliding block and a third cutting groove matched with the third sliding block are formed in the outer side of the circumference of the rotating wheel;

when the rotating wheel rotates to the first position, the proximal ends of the first sliding block, the second sliding block and the third sliding block are all abutted against the outer side of the circumference of the rotating wheel, the two ends of the first sliding plate are respectively pressed on the first crescent plate and the third crescent plate, the two ends of the second sliding plate are respectively pressed on the first crescent plate and the second crescent plate, and the two ends of the third sliding plate are respectively pressed on the second crescent plate and the third crescent plate; when the rotating wheel rotates to the second position, the proximal ends of the first sliding block and the second sliding block are abutted to the outer side of the circumference of the rotating wheel, the proximal end of the third sliding block is abutted to the third cutting groove, the two ends of the first sliding plate are respectively pressed on the first crescent plate and the third crescent plate, the two ends of the second sliding plate are respectively pressed on the first crescent plate and the second crescent plate, and the third sliding plate is separated from the second crescent plate and the third crescent plate; when the rotating wheel rotates to a third position, the proximal end of the first sliding block abuts against the outer side of the circumference of the rotating wheel, the proximal end of the second sliding block abuts against the second cutting groove, the proximal end of the third sliding block abuts against the third cutting groove, two ends of the first sliding plate are respectively pressed on the first crescent plate and the third crescent plate, the second sliding plate leaves the first crescent plate and the second crescent plate, and the third sliding plate leaves the second crescent plate and the third crescent plate; when the rotating wheel rotates to the fourth position, the proximal end of the first sliding block abuts against the first cutting groove, the proximal end of the second sliding block abuts against the second cutting groove, the proximal end of the third sliding block abuts against the third cutting groove, the first sliding plate leaves the first crescent plate and the third crescent plate, the second sliding plate leaves the first crescent plate and the second crescent plate, and the third sliding plate leaves the second crescent plate and the third crescent plate.

4. The oil pump of claim 3, wherein the seal cover plate is fixedly provided with a first motor for driving the rotating wheel to rotate.

5. The oil pump of claim 1, wherein the pump body has a first oil suction port at each first oil suction area, a first oil discharge port at each first oil discharge area, a second oil suction port at each second oil suction area, a second oil discharge port at each second oil discharge area, a third oil suction port at each third oil suction area, and a third oil discharge port at each third oil discharge area; the pump body is internally provided with an oil absorption ring groove communicated with the T port, a first oil absorption hole used for communicating the oil absorption ring groove with the first oil absorption port, a second oil absorption hole used for communicating the oil absorption ring groove with the second oil absorption port, and a third oil absorption hole used for communicating the oil absorption ring groove with the third oil absorption port.

6. The oil pump of claim 5, wherein a first oil hole communicating with the oil suction ring groove, a second oil hole communicating with the circular pump chamber, and a third oil hole communicating with the first oil hole and the second oil hole are provided in the pump body.

7. The oil pump of claim 5, wherein an oil discharge ring groove and a first oil discharge hole for communicating the P port with the oil discharge ring groove are provided in the pump body; an oil inlet of the first one-way valve is communicated with the first oil outlet, and an oil outlet of the first one-way valve is communicated with the oil discharge ring groove through a fourth oil hole formed in the pump body; the oil inlets of the second one-way valves are communicated with a second oil drain port, and the oil outlets are communicated with an oil drain ring groove through a fifth oil hole formed in the pump body; and the oil inlet of the third one-way valve is communicated with the third oil drain port, and the oil outlet of the third one-way valve is communicated with the oil drain ring groove through a sixth oil hole formed in the pump body.

Technical Field

The invention relates to the field of pumps, in particular to an oil pump.

Background

Gear pumps are rotary pumps that deliver or pressurize fluid by virtue of the change in working volume and movement created between a pump cylinder and a meshing gear. Two gears, a pump body and front and rear covers form two closed spaces, when the gears rotate, the volume of the space on the gear disengagement side is changed from small to large to form vacuum, liquid is sucked in, and the volume of the space on the gear engagement side is changed from large to small to squeeze the liquid into a pipeline; the advantages are that: the structure is simple, the volume is small, the weight is light, the number of parts is small, the manufacturability is good, the manufacture is easy, the maintenance is convenient, the price is low, and the self-absorption performance is good; the device is insensitive to the pollution of oil, is not easy to be seized or blocked in the working engineering, and can convey high-viscosity oil and fluid with large consistency. However, gear pumps also have the following disadvantages: large flow and pressure pulsation, large noise, low high-temperature efficiency, invariable discharge capacity and the like. Wherein the non-variable displacement limits the range of applications of the gear pump to a large extent.

Disclosure of Invention

The invention aims to provide an oil pump which is simple in structure and can change the displacement according to requirements.

In order to achieve the purpose, the invention provides the following technical scheme: an oil pump comprises a pump body, wherein a circular pump cavity with an opening at the left end is arranged at the left side of the pump body, a left end cover is fixedly arranged at the left end opening of the circular pump cavity at the left side of the pump body, an inner gear ring is connected in the circular pump cavity in a rotating mode, three first crescent tooth plates, three second crescent tooth plates and three third crescent tooth plates which are located on the inner side of the inner gear ring are uniformly arranged in the circular pump cavity along the circumferential interval, a first gear is rotatably connected between the first crescent tooth plates and the third crescent tooth plates between the left end cover and the pump body, a second gear is rotatably connected between the first crescent tooth plates and the second crescent tooth plates, a third gear is rotatably connected between the second crescent tooth plates and the third crescent tooth plates, the first gear, the second gear and the third gear are all meshed with the inner gear ring, and a rotating shaft extending out of the left end cover is arranged at the left; a P port and a T port are formed in the side face of the pump body, a first oil suction area and a first oil discharge area are formed in the circular pump cavity on two sides of the first gear meshed with the inner gear ring, a second oil suction area and a second oil discharge area are formed on two sides of the second gear meshed with the inner gear ring, and a third oil suction area and a third oil discharge area are formed on two sides of the third gear meshed with the inner gear ring; the first oil absorption area, the second oil absorption area and the third oil absorption area are all communicated with the T port; the first oil discharge area is communicated with the port P through a first one-way valve, the second oil discharge area is communicated with the port P through a second one-way valve, and the third oil discharge area is communicated with the port P through a third one-way valve;

a first sliding plate is connected between the first crescent plate and the third crescent plate in the circular pump cavity in a sliding mode along the radial direction, when two ends of the first sliding plate are pressed on the first crescent plate and the third crescent plate respectively, oil flows from the first oil suction area to the first oil discharge area along with the rotation of the first gear and the inner gear ring, and when the first sliding plate leaves the first crescent plate and the third crescent plate, the first oil suction area and the first oil discharge area on two sides of the first gear are communicated; a second sliding plate is connected between the first crescent tooth plate and the second crescent tooth plate in the circular pump cavity in a sliding mode along the radial direction, when two ends of the first sliding plate are pressed on the first crescent tooth plate and the second crescent tooth plate respectively, oil flows from the second oil suction area to the second oil discharge area along with the rotation of the second gear and the inner gear ring, and when the second sliding plate leaves the first crescent tooth plate and the second crescent tooth plate, the second oil suction area and the second oil discharge area on two sides of the second gear are communicated; and when the third sliding plate leaves the second crescent plate and the third crescent plate, the third oil suction areas and the third oil discharge areas on two sides of the third gear are communicated.

Furthermore, a first sliding groove is radially arranged at the position opposite to the first sliding plate in the pump body, a second sliding groove is radially arranged at the position opposite to the second sliding plate, and a third sliding groove is radially arranged at the position opposite to the third sliding plate; the first sliding plate is provided with a first shifting column extending into the first sliding groove, the second sliding plate is provided with a second shifting column extending into the second sliding groove, and the third sliding plate is provided with a third shifting column extending into the third sliding groove; and a variable control assembly for controlling the sliding of the first shifting column, the second shifting column and the third shifting column is arranged in the pump body.

Furthermore, the variable control assembly comprises a rotating wheel, a rotating groove is formed in the right side face of the pump body, the rotating groove and the circular pump cavity are in the same axial position, the rotating wheel is rotatably connected in the rotating groove, and a sealing cover plate is fixedly arranged on the right side face of the pump body at an opening of the rotating groove; first radial grooves, second radial grooves and third radial grooves communicated with the rotary grooves are uniformly arranged in the pump body at intervals along the circumferential direction of the rotary grooves; a first sliding block fixedly connected with the first shifting column is connected in the first radial groove in a sliding manner, a second sliding block fixedly connected with the second shifting column is connected in the second radial groove in a sliding manner, and a third sliding block fixedly connected with the third shifting column is connected in the third radial groove in a sliding manner; the far end of the first radial groove is provided with a first spring for forcing the first sliding block to be tightly pressed on the outer side of the rotating wheel, the far end of the second radial groove is provided with a second spring for forcing the second sliding block to be tightly pressed on the outer side of the rotating wheel, and the far end of the third radial groove is provided with a third spring for forcing the third sliding block to be tightly pressed on the outer side of the rotating wheel; a first cutting groove matched with the first sliding block, a second cutting groove matched with the second sliding block and a third cutting groove matched with the third sliding block are formed in the outer side of the circumference of the rotating wheel;

when the rotating wheel rotates to the first position, the proximal ends of the first sliding block, the second sliding block and the third sliding block are all abutted against the outer side of the circumference of the rotating wheel, the two ends of the first sliding plate are respectively pressed on the first crescent plate and the third crescent plate, the two ends of the second sliding plate are respectively pressed on the first crescent plate and the second crescent plate, and the two ends of the third sliding plate are respectively pressed on the second crescent plate and the third crescent plate; when the rotating wheel rotates to the second position, the proximal ends of the first sliding block and the second sliding block are abutted to the outer side of the circumference of the rotating wheel, the proximal end of the third sliding block is abutted to the third cutting groove, the two ends of the first sliding plate are respectively pressed on the first crescent plate and the third crescent plate, the two ends of the second sliding plate are respectively pressed on the first crescent plate and the second crescent plate, and the third sliding plate is separated from the second crescent plate and the third crescent plate; when the rotating wheel rotates to a third position, the proximal end of the first sliding block abuts against the outer side of the circumference of the rotating wheel, the proximal end of the second sliding block abuts against the second cutting groove, the proximal end of the third sliding block abuts against the third cutting groove, two ends of the first sliding plate are respectively pressed on the first crescent plate and the third crescent plate, the second sliding plate leaves the first crescent plate and the second crescent plate, and the third sliding plate leaves the second crescent plate and the third crescent plate; when the rotating wheel rotates to the fourth position, the proximal end of the first sliding block abuts against the first cutting groove, the proximal end of the second sliding block abuts against the second cutting groove, the proximal end of the third sliding block abuts against the third cutting groove, the first sliding plate leaves the first crescent plate and the third crescent plate, the second sliding plate leaves the first crescent plate and the second crescent plate, and the third sliding plate leaves the second crescent plate and the third crescent plate.

Furthermore, a first motor for driving the rotating wheel to rotate is fixedly arranged on the sealing cover plate.

Furthermore, a first oil suction port is arranged at the first oil suction area, a first oil discharge port is arranged at the first oil discharge area, a second oil suction port is arranged at the second oil suction area, a second oil discharge port is arranged at the second oil discharge area, a third oil suction port is arranged at the third oil suction area, and a third oil discharge port is arranged at the third oil discharge area in the pump body; the pump body is internally provided with an oil absorption ring groove communicated with the T port, a first oil absorption hole used for communicating the oil absorption ring groove with the first oil absorption port, a second oil absorption hole used for communicating the oil absorption ring groove with the second oil absorption port, and a third oil absorption hole used for communicating the oil absorption ring groove with the third oil absorption port.

Furthermore, a first oil hole communicated with the oil suction ring groove, a second oil hole communicated with the circular pump cavity and a third oil hole used for communicating the first oil hole and the second oil hole are formed in the pump body.

Further, an oil discharge ring groove and a first oil discharge hole for communicating the P port with the oil discharge ring groove are formed in the pump body; an oil inlet of the first one-way valve is communicated with the first oil outlet, and an oil outlet of the first one-way valve is communicated with the oil discharge ring groove through a fourth oil hole formed in the pump body; the oil inlets of the second one-way valves are communicated with a second oil drain port, and the oil outlets are communicated with an oil drain ring groove through a fifth oil hole formed in the pump body; and the oil inlet of the third one-way valve is communicated with the third oil drain port, and the oil outlet of the third one-way valve is communicated with the oil drain ring groove through a sixth oil hole formed in the pump body.

Advantageous effects

Compared with the prior art, the technical scheme of the invention has the following advantages:

1. the displacement of the gear pump is changed by changing the positions of the first sliding plate, the second sliding plate and the third sliding plate through the rotating wheel;

2. the gear pump realizes multi-gear change of the displacement of the gear pump in a mode of changing the positions of the first sliding plate, the second sliding plate and the third sliding plate through the rotating wheel and a mode of matching the first gear, the second gear and the third gear.

Drawings

FIG. 1 is a cross-sectional view of the present invention;

FIG. 2 is a sectional view taken along line A-A of FIG. 1 in accordance with the present invention;

FIG. 3 is a sectional view taken along line B-B of FIG. 1 in accordance with the present invention;

FIG. 4 is a cross-sectional view taken along line C-C of FIG. 1 in accordance with the present invention;

FIG. 5 is a cross-sectional view taken along line D-D of FIG. 1 in accordance with the present invention;

FIG. 6 is a sectional view taken in the direction A-A of FIG. 1 with one of the gears inoperative in accordance with the present invention;

FIG. 7 is a cross-sectional view taken in the direction D-D of FIG. 1 illustrating the operation of one of the ring gears in accordance with the present invention;

FIG. 8 is a sectional view taken in the direction A-A of FIG. 1 with the two ring gears inoperative in accordance with the present invention;

FIG. 9 is a cross-sectional view taken in the direction D-D of FIG. 1 with the two ring gears inoperative in accordance with the present invention;

FIG. 10 is a cross-sectional view taken in the direction A-A of FIG. 1 at zero displacement in accordance with the present invention;

fig. 11 is a cross-sectional view taken in the direction D-D of fig. 1 at zero displacement in accordance with the present invention.

Detailed Description

Referring to fig. 1 to 11, an oil pump includes a pump body 1, a circular pump cavity 1g with an open left end is disposed on a left side of the pump body 1, a left end cover 101 is fixedly disposed on the left side of the pump body 1 at the left end opening of the circular pump cavity 1g, an inner gear ring 4 is rotatably connected to the circular pump cavity 1g, three first crescent plates 6a, second crescent plates 6b and third crescent plates 6c are circumferentially and uniformly arranged in the circular pump cavity 1g and located inside the inner gear ring 4, a first gear 2a is rotatably connected between the first crescent plate 6a and the third crescent plate 6c between the left end cover 101 and the pump body 1, a second gear 3a is rotatably connected between the first crescent plate 6a and the second crescent plate 6b, a third gear 3b is rotatably connected between the second crescent plate 6b and the third crescent plate 6c between the first crescent plate 2a and the third crescent plate 2b, The second gear 3a and the third gear 3b are both meshed with the inner gear ring 4, and the left end of the first gear 2a is provided with a rotating shaft 2b extending out of the left end cover 101; a P port and a T port are formed in the side surface of the pump body 1, a first oil suction area 2a1 and a first oil discharge area 2a2 are formed in the circular pump cavity 1g on both sides of the first gear 2a engaged with the ring gear 4, a second oil suction area 3a1 and a second oil discharge area 3a2 are formed on both sides of the second gear 3a engaged with the ring gear 4, and a third oil suction area 3b1 and a third oil discharge area 3b2 are formed on both sides of the third gear 3b engaged with the ring gear 4; the first oil absorption area 2a1, the second oil absorption area 3a1 and the third oil absorption area 3b1 are all communicated with a T port; the first oil discharge area 2a2 communicates with port P through a first check valve 7a, the second oil discharge area 3a2 communicates with port P through a second check valve 7b, and the third oil discharge area 3b2 communicates with port P through a third check valve 7 c.

A first sliding plate 5a is connected between the first crescent plate 6a and the third crescent plate 6c in the circular pump chamber 1g in a sliding manner along a radial direction, when two ends of the first sliding plate 5a are respectively pressed on the first crescent plate 6a and the third crescent plate 6c, oil flows from the first oil suction area 2a1 to the first oil discharge area 2a2 along with the rotation of the first gear 2a and the inner gear ring 4, and when the first sliding plate 5a leaves the first crescent plate 6a and the third crescent plate 6c, the first oil suction area 2a1 and the first oil discharge area 2a2 on two sides of the first gear 2a are communicated; a second sliding plate 5b is connected between the first crescent plate 6a and the second crescent plate 6b in the circular pump cavity 1g in a sliding manner along the radial direction, when two ends of the first sliding plate 5a are respectively pressed on the first crescent plate 6a and the second crescent plate 6b, oil flows from the second oil suction area 3a1 to the second oil discharge area 3a2 along with the rotation of the second gear 3a and the inner gear ring 4, and when the second sliding plate 5b leaves the first crescent plate 6a and the second crescent plate 6b, the second oil suction area 3a1 and the second oil discharge area 3a2 on two sides of the second gear 3a are communicated; a third sliding plate 5c is connected in the circular pump cavity 1g in a sliding manner in the radial direction between the second crescent plate 6b and the third crescent plate 6c, when two ends of the third sliding plate 5c are respectively pressed on the second crescent plate 6b and the third crescent plate 6c, oil flows from the third oil suction area 3b1 to the third oil discharge area 3b2 as the third gear 3b and the ring gear 4 rotate, and when the third sliding plate 5c leaves the second crescent plate 6b and the third crescent plate 6c, the third oil suction area 3b1 and the third oil discharge area 3b2 on two sides of the third gear 3b are communicated.

A first sliding chute 1r is arranged in the pump body 1 along the radial direction at a position opposite to the first sliding plate 5a, a second sliding chute 1s is arranged in the pump body 1 along the radial direction at a position opposite to the second sliding plate 5b, and a third sliding chute 1t is arranged in the pump body 1 along the radial direction at a position opposite to the third sliding plate 5 c; the first sliding plate 5a is provided with a first shifting column 5a1 extending into the first sliding chute 1r, the second sliding plate 5b is provided with a second shifting column 5b1 extending into the second sliding chute 1s, and the third sliding plate 5c is provided with a third shifting column 5c1 extending into the third sliding chute 1 t; the pump body 1 is internally provided with a variable control assembly for controlling the sliding of the first toggle column 5a1, the second toggle column 5b1 and the third toggle column 5c 1.

The variable control assembly comprises a rotating wheel 10, a rotating groove 103 is formed in the right side surface of the pump body 1, the rotating groove 103 and the circular pump cavity 1g are in the same axial position, the rotating wheel 10 is rotatably connected into the rotating groove 103, a sealing cover plate 102 is fixedly arranged on the right side surface of the pump body 1 at the opening of the rotating groove 103, and a first motor 11 for driving the rotating wheel 10 to rotate is fixedly arranged on the sealing cover plate 102; first radial grooves 104, second radial grooves 105 and third radial grooves 106 communicated with the rotary groove 103 are uniformly arranged in the pump body 1 at intervals along the circumferential direction of the rotary groove 103; a first sliding block 8a fixedly connected with the first shifting column 5a1 is connected in the first radial groove 104 in a sliding manner, a second sliding block 8b fixedly connected with the second shifting column 5b1 is connected in the second radial groove 105 in a sliding manner, and a third sliding block 8c fixedly connected with the third shifting column 5c1 is connected in the third radial groove 106 in a sliding manner; the far end of the first radial groove 104 is provided with a first spring 9a for forcing the first slide block 8a to press the outer side of the rotating wheel 10, the far end of the second radial groove 105 is provided with a second spring 9b for forcing the second slide block 8b to press the outer side of the rotating wheel 10, and the far end of the third radial groove 106 is provided with a third spring 9c for forcing the third slide block 8c to press the outer side of the rotating wheel 10; the outer side of the circumference of the rotating wheel 10 is provided with a first cutting groove 10a matched with the first sliding block 8a, a second cutting groove 10b matched with the second sliding block 8b and a third cutting groove 10c matched with the third sliding block 8 c.

When the runner 10 rotates to the first position, the proximal ends of the first slider 8a, the second slider 8b and the third slider 8c are all abutted against the outer side of the circumference of the runner 10, two ends of the first sliding plate 5a are respectively pressed on the first crescent plate 6a and the third crescent plate 6c, two ends of the second sliding plate 5b are respectively pressed on the first crescent plate 6a and the second crescent plate 6b, and two ends of the third sliding plate 5c are respectively pressed on the second crescent plate 6b and the third crescent plate 6 c; when the runner 10 rotates to the second position, the proximal ends of the first slider 8a and the second slider 8b both abut against the outer side of the circumference of the runner 10, the proximal end of the third slider 8c abuts against the third cutting groove 10c, the two ends of the first sliding plate 5a respectively press the first crescent plate 6a and the third crescent plate 6c, the two ends of the second sliding plate 5b respectively press the first crescent plate 6a and the second crescent plate 6b, and the third sliding plate 5c leaves the second crescent plate 6b and the third crescent plate 6 c; when the runner 10 rotates to the third position, the proximal end of the first slider 8a abuts against the outer side of the circumference of the runner 10, the proximal end of the second slider 8b abuts against the second slot 10b, the proximal end of the third slider 8c abuts against the third slot 10c, two ends of the first sliding plate 5a are respectively pressed on the first crescent plate 6a and the third crescent plate 6c, the second sliding plate 5b is separated from the first crescent plate 6a and the second crescent plate 6b, and the third sliding plate 5c is separated from the second crescent plate 6b and the third crescent plate 6 c; when the rotating wheel 10 rotates to the fourth position, the proximal end of the first sliding block 8a abuts in the first notch 10a, the proximal end of the second sliding block 8b abuts in the second notch 10b, the proximal end of the third sliding block 8c abuts in the third notch 10c, the first sliding plate 5a leaves the first crescent plate 6a and the third crescent plate 6c, the second sliding plate 5b leaves the first crescent plate 6a and the second crescent plate 6b, and the third sliding plate 5c leaves the second crescent plate 6b and the third crescent plate 6 c.

A first oil suction port 1b is arranged at the first oil suction area 2a1 in the pump body 1, a first oil discharge port 1a is arranged at the first oil discharge area 2a2, a second oil suction port 1d is arranged at the second oil suction area 3a1, a second oil discharge port 1c is arranged at the second oil discharge area 3a2, a third oil suction port 1f is arranged at the third oil suction area 3b1, and a third oil discharge port 1e is arranged at the third oil discharge area 3b 2; an oil suction ring groove 1k communicated with the T port, a first oil suction hole 31 communicated with the oil suction ring groove 1k and the first oil suction port 1b, a second oil suction hole 32 communicated with the oil suction ring groove 1k and the second oil suction port 1d, and a third oil suction hole 33 communicated with the oil suction ring groove 1k and the third oil suction port 1f are arranged in the pump body 1. The pump body 1 is provided with a first oil hole 1j communicated with the oil suction ring groove 1k, a second oil hole 1h communicated with the circular pump chamber 1g, and a third oil hole 1i for communicating the first oil hole 1j with the second oil hole 1 h.

An oil discharge ring groove 1P and a first oil discharge hole 1q for communicating a port P with the oil discharge ring groove 1P are arranged in the pump body 1; an oil inlet of the first one-way valve 7a is communicated with the first oil discharge port 1a, and an oil outlet of the first one-way valve is communicated with the oil discharge ring groove 1p through a fourth oil hole 1m formed in the pump body 1; the oil inlets of the second one-way valves 7b are communicated with a second oil drain port 1c, and the oil outlets are communicated with an oil drain ring groove 1p through fifth oil holes 1n arranged in the pump body 1; and the oil inlets of the third one-way valves 7c are communicated with a third oil drain port 1e, and the oil outlets are communicated with an oil drain ring groove 1p through a sixth oil hole 1o formed in the pump body 1.

When the gear pump works, firstly, the first motor 11 controls the rotating wheel 10 to rotate to a first position, the rotating shaft 2b needs to be connected with the motor, the motor is electrified to drive the rotating shaft 2b to rotate, the rotating shaft 2b drives the first gear 2a to rotate when rotating, the first gear 2a drives the inner gear ring 4 meshed with the first gear to rotate, and the inner gear ring 4 drives the second gear 3a and the third gear 3b to rotate when rotating; therefore, when the pump body 1 generates negative pressure, hydraulic oil enters the first oil suction area 2a1 from the port T through the oil suction ring groove 1k, the first oil suction hole 31 and the first oil suction hole 1b and passes through the rotation of the first gear 2a and the ring gear 4, the hydraulic oil is compressed and brought to the first oil discharge area 2a2, passes through the first oil discharge hole 1a, the first check valve 7a, the fourth oil hole 1m, the oil discharge ring groove 1P and the first oil discharge hole 1q and flows out of the port P, meanwhile, the hydraulic oil entering the oil suction ring groove 1k enters the first oil suction area 2a1 through the second oil suction hole 32 and the second oil suction hole 1d and passes through the rotation of the second gear 3a and the ring gear 4, the hydraulic oil is compressed and brought to the second oil discharge area 3a2, passes through the second oil discharge hole 1c, the second check valve 7b, the fifth oil hole 1n, the oil discharge ring groove 1P and the first oil discharge hole 1q and flows out of the port P, and the hydraulic oil entering, The third oil suction port 1f enters the third oil suction area 3b1 and the hydraulic oil is compressed and brought to the third oil discharge area 3b2 through the third oil discharge port 1e, the third check valve 7c, the sixth oil hole 1o, the oil discharge ring groove 1P and the first oil discharge hole 1q and flows out of the port P by the rotation of the third gear 3b and the ring gear 4. The full displacement of the gear pump is realized (as shown in fig. 2), so that the oil pump can complete the normal operation of the full displacement.

When the oil pump needs to be varied, the first motor 11 rotates by 30 degrees to drive the rotating wheel 10 to rotate to the second position, the third spring 9c pushes the third sliding block 8c, so that the proximal end of the third sliding block 8c enters the third cutting groove 10c, and because the third shifting column 5c1 is in sliding fit in the third sliding groove 1T, the third sliding plate 5c slides towards the direction of the center of the circular pump cavity 1g, so that the third oil discharge area 3b2 is communicated with the second oil hole 1h (as shown in fig. 6 and 7), at this time, the hydraulic oil in the third oil suction area 3b1 is driven by the third gear 3b to enter the third oil discharge area 3b2, then passes through the second oil hole 1h, the third oil hole 1i, the first oil hole 1j and the oil suction ring groove 1k and then returns to the T-port, no pressure is generated, and the third gear 3b forms self-circulation, so that the original two-thirds gear pump is changed.

When the oil pump needs to change the variable, the first motor 11 rotates 60 degrees to drive the rotating wheel 10 to rotate to the third position, the third spring 9c pushes the third slider 8c, so that the proximal end of the third slider 8c enters the third slot 10c, the second spring 9b pushes the second slider 8b, so that the proximal end of the second slider 8b enters the second slot 10b, because the third shifting column 5c1 is in sliding fit in the third sliding slot 1T, the second shifting column 5b1 is in sliding fit in the second sliding slot 1s, the third sliding plate 5c and the second sliding plate 5b slide in the direction close to the center of the circular pump cavity 1g, so that the third oil discharge area 3b2 and the second oil discharge area 3a2 are communicated with the second oil hole 1h, at this time, the hydraulic oil in the third oil suction area 3b1 drives the third oil discharge area 3b2 through the third gear 3b, and then returns to the oil hole 1h, the third oil hole 1i, the first oil suction hole 1j, and the first ring groove 1k, pressure is not generated, meanwhile, the hydraulic oil in the second oil suction area 3a1 is driven by the second gear 3a to enter the second oil discharge area 3a2, then passes through the second oil hole 1h, the third oil hole 1i, the first oil hole 1j and the oil suction ring groove 1k, and then returns to the T port, and no pressure is generated; self-circulation is formed at the third gear 3b and the second gear 3a, so that the displacement of the gear pump is changed to one third of the original displacement.

When the oil pump needs to be changed, the first motor 11 rotates by 90 degrees to drive the rotating wheel 10 to rotate to a fourth position, the third spring 9c pushes the third sliding block 8c to enable the proximal end of the third sliding block 8c to enter the third cutting groove 10c, the second spring 9b pushes the second sliding block 8b to enable the proximal end of the second sliding block 8b to enter the second cutting groove 10b, and the first spring 9a pushes the first sliding block 8a to enable the proximal end of the first sliding block 8a to enter the first cutting groove 10 a; since the third toggle lever 5c1 is slidably fitted in the third sliding groove 1t, the second toggle lever 5b1 is slidably fitted in the second sliding groove 1s, and the first toggle lever 5a1 is slidably fitted in the first sliding groove 1 r; the third sliding plate 5c, the second sliding plate 5b and the first sliding plate 5a slide towards the direction close to the center of the circular pump chamber 1g, so that the third oil discharge area 3b2, the second oil discharge area 3a2 and the first oil discharge area 2a2 are communicated with the second oil holes 1 h; at this time, the hydraulic oil in the third oil absorption area 3b1 is driven by the third gear 3b to enter the third oil discharge area 3b2, then passes through the second oil hole 1h, the third oil hole 1i, the first oil hole 1j and the oil absorption ring groove 1k and then returns to the T port, no pressure is generated, the hydraulic oil in the second oil absorption area 3a1 is driven by the second gear 3a to enter the second oil discharge area 3a2, then passes through the second oil hole 1h, the third oil hole 1i, the first oil hole 1j and the oil absorption ring groove 1k and then returns to the T port, no pressure is generated, the hydraulic oil in the first oil absorption area 2a1 is driven by the first gear 2a to enter the first oil discharge area 2a2, then passes through the second oil hole 1h, the third oil hole 1i, the first oil hole 1j and the oil absorption ring groove 1k and then returns to the T port, and no pressure is generated; self-circulation is formed at the third gear 3b, the second gear 3a and the first gear 2a, so that the gear pump displacement becomes zero.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the technical principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.