CN113833595A

CN113833595A - Shell rotation type cycloid motor with oil drainage function

Info

Publication number: CN113833595A
Application number: CN202111260184.1A
Authority: CN
Inventors: 曹伟
Original assignee: Individual
Current assignee: Individual
Priority date: 2021-10-28
Filing date: 2021-10-28
Publication date: 2021-12-24

Abstract

The invention belongs to the field of cycloid hydraulic motors, and particularly relates to a shell rotary type cycloid motor with an oil drainage function, which comprises a rotating part and a fixing part, wherein the inside of the rotating part is connected with the fixing part in a matched manner, and a hydraulic shaft seal is arranged at the matched connection position of the fixing part and the rotating part; still including draining the oil pocket, the periphery side of fixed part and rotating part cooperation junction is located in the draining chamber, drain the oil pocket with fixed part and rotating part cooperation junction intercommunication, still be equipped with the draining mouth on the fixed part, the draining mouth passes through draining oil circuit and draining chamber intercommunication. By adding the design of the splitter plate and the compensation disc, the problem that the oil drainage function of the similar shaft rotating motor cannot be increased is solved, and after the oil drainage cavity is added, the pressure of the shaft seal treatment of the motor can be reduced, so that the motor can use a common hydraulic shaft seal, the manufacturing cost is reduced, the service life of the hydraulic shaft seal is prolonged, and the maintenance cost is reduced; and adopt the shell to rotate can effectively shorten the axial length of motor, conveniently be applied to the walking drive of small-size machinery.

Description

Shell rotation type cycloid motor with oil drainage function

Technical Field

The invention belongs to the field of cycloid hydraulic motors, and particularly relates to a shell-rotation type cycloid motor with an oil drainage function.

Background

The cycloid hydraulic motor is a common hydraulic driving device, is a low-speed large-torque motor, has the advantages of small volume, high unit power density, high efficiency, wide rotating speed range and the like, is widely applied, and is more widely applied along with the improvement of the development level of industry and agriculture.

The cycloid hydraulic motor in the prior art is provided with an output shaft, the axial size is long, when the cycloid hydraulic motor is applied to small-size machines such as a miniature excavator and used as a walking motor, the motor cannot be completely installed within the width of a crawler belt due to the long axial size and can exceed the protection range of the crawler belt, and when the machine walks, the motor is easily damaged due to the severe ground conditions.

The use of the shell-and-turn gerotor motor enables the output shaft to be omitted, thereby reducing the axial dimension. The axial type cycloid motor in the prior art cannot increase an oil leakage path due to structural limitation, and when the cycloid motor lacking an oil leakage function is used, the motor needs to be assembled with a hydraulic shaft seal capable of bearing high pressure, the price is high, the cycloid motor is very easy to damage, once the hydraulic shaft seal is damaged, the motor needs to be disassembled and replaced, and the maintenance frequency and the cost are greatly improved.

Disclosure of Invention

Aiming at the problems, the invention provides a shell rotary type cycloid motor with an oil drainage function, which solves the problem that the oil drainage function of the similar shaft rotary motor cannot be increased by increasing the design of a splitter vane and a compensation disc, and can reduce the pressure of shaft seal treatment of the motor after an oil drainage cavity is increased, so that the motor can use a common hydraulic shaft seal, the manufacturing cost is reduced, the service life of the hydraulic shaft seal is prolonged, and the maintenance cost is reduced; and adopt the shell to rotate can effectively shorten the axial length of motor, conveniently be applied to the walking drive of small-size machinery.

The scheme provided by the invention is as follows:

the utility model provides a shell rotation formula cycloid motor with draining function, includes rotating part and fixed part, the fixed part outside is located to rotating part pot head to but with fixed part swivelling joint, the rotating part is inside to be connected with the fixed part cooperation, the cooperation junction is equipped with hydraulic shaft seal. The invention adopts a shell rotary type cycloid motor, the rotating part rotates to output power during operation, and the hydraulic oil seal is used for providing sealing during rotation. When the motor operates, due to the fact that relative rotation exists between the rotating portion and the fixing portion, hydraulic oil can leak from the matching connection portion of the rotating portion and the fixing portion and enter the motor oil leakage cavity, the hydraulic shaft seal seals the leaked hydraulic oil to avoid leaking out of the motor, and therefore the hydraulic shaft seal needs to bear the pressure of the hydraulic oil of the oil leakage cavity.

Still include the integral key shaft, integral key shaft one end stretches into inside the rotating part and is connected with the rotating part, and the other end stretches into inside the fixed part and is connected with the fixed part.

Specifically, the rotating part includes protecgulum, balance plate, outer rotor, valve plate and the wheel hub that connects gradually, protecgulum, balance plate, outer rotor, valve plate and wheel hub all can be around center pin synchronous revolution. The structure of the front cover, the balance disc, the outer rotor and the valve plate is a hydraulic cycloid motor working structure in the prior art, and also comprises an inner rotor, wherein the inner rotor is arranged in the outer rotor, the inner rotor is matched with the outer rotor, the balance disc and the valve plate to form a working oil cavity, the working oil cavity is divided into a plurality of oil cavities by the inner rotor and the outer rotor, one part of the working oil cavity is a high-pressure oil cavity, the other part of the working oil cavity is a low-pressure oil cavity, the inner rotor is driven by pressure difference to revolve in the outer rotor, and the high-pressure oil cavity and the low-pressure oil cavity are sequentially replaced by the revolution of the inner rotor to generate continuous power. The hydraulic oil flows into the working oil cavity after being distributed by the distribution plate to provide hydraulic power.

The ordinary cycloid motor is different from an ordinary cycloid motor in that the inner rotor revolves in the outer rotor (in the ordinary cycloid motor, the part is a stator) and simultaneously generates autorotation, the rotation is transmitted to a spline shaft connected with the inner rotor, and the spline shaft drives an output shaft to output power. The shell-rotation type cycloid motor drives the integral rotating part to rotate by hydraulic power, and the inner rotor only revolves and does not rotate when working, namely, a spline shaft connected with the inner rotor does not output power. The wheel hub in the rotating part is connected with the outer periphery side of the fixing part in a sleeved mode through the bearing, so that the whole rotating part can rotate, power output is directly carried out through the rotating part, an output shaft is not needed, the axial length is effectively reduced, and a driven tire or a driven crawler belt can be directly installed on the wheel hub to be driven.

The fixed part comprises a shell, a central oil cavity is formed in the shell and is communicated with the working oil cavity through a flow distribution plate, the fixed part further comprises a spline shaft sleeve, the spline shaft sleeve is arranged in the central oil cavity, one end of the spline shaft is connected with the spline shaft sleeve in a matched mode, and the spline shaft sleeve is only used as a connecting piece of the spline shaft and does not output power.

As described above, the hub is mounted outside the housing via a bearing and is rotatably connected to the housing.

The shell is provided with a first oil port and a second oil port, the first oil port is communicated with the working oil cavity through the flow distribution plate, and the second oil port is communicated with the central oil cavity. The first oil port and the second oil port are power connectors of the cycloid motor and are connected with a hydraulic oil source. One of the two oil ports is connected with the oil inlet, and the other one is connected with the oil return port, so that the output direction of the hydraulic oil source can be adjusted to be changed alternately. The oil port when communicated with the oil inlet is a high-pressure oil port, high-pressure oil enters a high-pressure cavity in the working oil cavity after flow distribution, and flows out of the oil return port through a channel after work is done, so that the circulating work of hydraulic oil is completed.

After the installation, relative rotation exists between the flow distribution plate and the shell, hydraulic oil at the communication position of the flow distribution hole and the first oil port can leak out from a hydraulic balance gap between the tightly attached flow distribution plate and a compensation plate arranged on the shell, and the purpose of the hydraulic shaft seal is to seal the leaked hydraulic oil. In the existing shaft rotating motor product in the market, when the central oil cavity is a high-pressure cavity, the hydraulic oil seal bears the high pressure output by the hydraulic oil source, so in the prior art, the selection of the hydraulic shaft seal needs to select a specific hydraulic shaft seal capable of bearing the high pressure, the hydraulic shaft seal is expensive, and the cost of the whole motor is greatly improved.

In order to solve the problem, the invention designs an oil drainage cavity, the position of the oil drainage cavity is positioned on the outer peripheral side of the matching contact surface of the rotating part and the fixed part, namely on the shell on the outer peripheral side of the contact surface of the distributing plate and the shell, and the oil drainage cavity is communicated with the contact surface of the distributing plate and a compensating plate mounted on the shell. Because there is relative motion in the cooperation contact surface of rotating part and fixed part, high-pressure oil flows into through the gap of this cooperation contact surface and lets out the oil pocket, again through the draining oil circuit of being connected with draining the oil pocket, flows from draining the mouth, reduces the pressure that lets out the oil pocket for hydraulic pressure oil blanket need not to undertake too high pressure, thereby can select ordinary hydraulic pressure oil blanket in the assembly can, reduction in manufacturing cost.

In order to structurally realize the structure of an oil drainage cavity, the invention is provided with a compensation disc, the compensation disc is arranged in a central oil cavity, the spline shaft penetrates through the compensation disc, one end of the compensation disc is connected with the shell, and the other end of the compensation disc is in contact connection with the valve plate; and a plurality of compensation oil through holes are formed in the compensation disc, one end of each compensation oil through hole is communicated with the first oil port, and the other end of each compensation oil through hole is communicated with the working oil cavity through the flow distribution hole of the flow distribution disc. Meanwhile, the flow distribution plate is additionally provided with a flow distribution plate on one side of a plurality of combined type flow distribution plates in the prior art, one side of the flow distribution plate is connected with the combined type flow distribution plate, the center part of the other side of the flow distribution plate is provided with a protruding end, and the protruding end extends into the shell and is in contact connection with the compensation plate; the flow distribution plate is provided with a flow distribution oil through hole, one end of the flow distribution oil through hole is communicated with the flow distribution hole, and the other end of the flow distribution oil through hole is communicated with the compensation oil through hole; the hydraulic shaft seal is arranged at the outer side of the protruding end. The smooth circulation of hydraulic oil when rotatory can be guaranteed in the cooperation work of compensation oil through hole and reposition of redundant personnel oil through the design of the protruding end of flow distribution piece, simultaneously, moves into inside the casing with hydraulic oil seal's position for there is enough space on the casing and can set up the oil drainage chamber, and the oil drainage chamber is opened promptly and is established on the protruding end of flow distribution piece and the casing of the contact surface week side of compensation dish. When the first oil port is an oil inlet, high-pressure oil enters the flow distribution plate for flow distribution after passing through the compensation oil through hole and the shunt oil through hole, and flows out of a gap between the compensation oil through hole and the shunt oil through hole, flows into the oil relief cavity and flows out of the oil relief hole when the motor rotates; and when the first oil port is an oil return port, the compensation oil through hole and the shunting oil through hole are both low-pressure passages, and the outflow oil amount is little, so that the pressure of the oil relief cavity is low and is nearly zero.

The oil drainage cavity is connected to an oil drainage port arranged on the valve body through an oil drainage oil path, and the oil drainage port is usually connected with an oil pipe to the oil tank so that oil drainage flows back to the oil tank for recovery. And in actual work, because increase an oil pipe and probably lead to reasons such as the cloth pipe is inconvenient, can seal the draining port and do not use, consequently can set up detachable end cap on the draining port usually. In design, the oil drainage oil way is respectively communicated with the first oil port and the second oil port through the one-way valve, and when the oil drainage port is normally used, oil in the oil drainage oil way flows out of the oil drainage port; when the oil drain port is closed, because the hydraulic oil in the oil drain oil path opens the one-way valve communicated with the oil return port, the oil in the oil drain oil path flows into the oil return port and flows out together with the return oil of the oil return port, and because the pressure of the oil return port is not high, the common shaft seal can meet the requirement; normally, the pressure at the return port is negligibly low.

Compared with the prior art, the invention has the advantages that:

1. the oil relief cavity is arranged, so that the hydraulic shaft seal does not need to bear high pressure, the common hydraulic shaft seal can be used, the manufacturing cost is reduced, the service life of the hydraulic shaft seal is prolonged, and the maintenance cost is reduced.

2. Through the design of splitter vane and compensating disc, solve the problem that prior art axle cycloid motor can't increase the draining function in structure.

3. The shell rotating type motor can effectively shorten the axial length of the motor, and is conveniently applied to the walking drive of small machinery.

Drawings

Fig. 1 is a sectional structure view of the present application.

Fig. 2 is a sectional view of the port plate.

Fig. 3 is a front view of the port plate.

Fig. 4 is a sectional view of the compensating disc.

Fig. 5 is a front view of the compensating disc.

FIG. 6 is a sectional view taken along the line A-A.

Fig. 7 is a sectional view of the first oil passage.

Fig. 8 is a sectional view of the second oil passage.

In the figure, 1, a front cover, 2, a spline shaft, 3, an inner rotor, 4, a bolt, 5, an outer rotor, 6, a flow distribution disc, 7, a flow distribution sheet, 8, a hub, 9, a shell, 10, an oil drainage port, 11, a spline sleeve, 12, a central oil cavity, 13, an oil drainage oil way, 14, a bearing, 15, an oil drainage cavity, 16, a compensation oil through hole, 17, a flow distribution oil through hole, 18, a balance disc, 19, a compensation disc, 19-1, a first joint, 19-2, a second joint, 19-3, a third joint, 20, a one-way valve, 21, a second oil way channel, 22, a second oil port, 23, a first oil port, 24, a first oil way channel, 25 and a hydraulic shaft seal.

Detailed Description

The invention is further illustrated below with reference to the figures and examples.

As shown in fig. 1, a shell-and-turn type cycloid motor with a drain function includes a rotating portion and a fixing portion.

The rotating part is the protecgulum 1, balance disc 18, outer rotor 5, valve plate 6, wheel hub 8 in proper order from left to right, and above-mentioned part passes through bolt 4 zonulae occludens, all has the sealing washer to connect the sealed of gap between each part, prevents the oil leak. An inner rotor 3 is arranged in the outer rotor 5, a spline shaft 2 is connected to the center of the inner rotor 3, and the fitting installation mode of the front cover 1, the balance disc 18, the outer rotor 5, the inner rotor 3, the spline shaft 2 and the port plate 6 is the installation mode of the cycloid motor in the prior art.

The fixed part comprises a shell 9, a semi-closed central cavity is formed in the axis position of a motor inside the shell 9, the spline shaft 2 extends into the central cavity from the opening, a compensation disc 19 and a spline housing 11 are sequentially arranged along the extending direction of the spline shaft 2, and one end, extending into the shell, of the spline shaft 2 is connected with the spline housing 11. And a sealing ring is also arranged between the outer peripheral sides of the compensating disc 19 and the spline sleeve 11 and the inner wall of the shell.

The hub 8 is fitted on the outer peripheral side of the housing on the inner peripheral side thereof, and a bearing 14 is mounted between the hub 8 and the housing 2 so that the hub 8 can rotate about the outer peripheral side of the housing 9 about the motor axis. A portion capable of engaging with the hub 8 is provided on the outer peripheral side of the case 2, and the portion where the hub 8 and the case 9 engage with each other is sealed with a seal ring.

As shown in fig. 1, 2 and 3, the port plate 6 is a multi-piece composite port plate, that is, it is formed by combining and welding a plurality of port plates provided with specific holes, and the hole shapes of the port plates are combined with each other to form a port hole for operation. The valve plate of this embodiment still welds a slice splitter plate 7 on prior art multi-disc combined type valve plate 6's right side, and the diameter of splitter plate 7 is the same with other valve plates, and there is the arch of cylinder in the central part on right side, and the internal diameter at the inside central cavity left side opening part of casing 9 cooperatees with the diameter of bulge, and after the installation of accomplishing wheel hub 8 and casing 9, the bulge of splitter plate 7 can stretch into central cavity and form the cooperation. The hydraulic oil seal 25 is fitted around the outer peripheral side of the above-mentioned projecting portion. The splitter plate 7 is provided with a splitter oil through hole 17 which can be communicated with the flow distribution hole, and the working state of the original flow distribution hole is not influenced.

As shown in fig. 1, 4 and 5, a compensation disc 17 is disposed in the middle cavity of the housing 9 near the opening, and a through hole is formed in the middle of the compensation disc 17 for the spline shaft to pass through. The compensating disc 17 is in the shape of three hollow cylinders with successively reduced diameters, when the compensating disc is installed, the section with the smallest diameter is taken as a first section 19-1, the first section 19-1 is fixedly pressed with the inner wall of the shell, and a sealing ring is arranged on the outer periphery side; the second section 19-2 is also fixedly pressed against the inner wall of the shell, a sealing ring is arranged on the periphery of the second section, and a gap is reserved between the surface of the second section 19-2 and the inner wall of the right shell and serves as an oil passage; the left side of the third section 19-3 abuts the raised portion of the splitter plate 7 after the motor assembly is complete. The compensating disc 19 is provided with a plurality of compensating oil through holes 16 which transversely penetrate through the third section 19-3 and the second section 19-2, and the compensating oil through holes 16 can be matched with the shunting oil through holes 17 to work.

After the motor is assembled, a central oil cavity 12 of the motor is formed by the middle through hole of the port plate 6, the middle through hole of the compensating plate 19 and the middle cavity of the shell 9, and the spline shaft 2 is installed in the central oil cavity 12.

An oil drainage cavity 15 is formed in the lower shell of the compensation disc 19, and the oil drainage cavity 15 is communicated with a gap between the flow distribution sheet 7 and the compensation disc 19, so that oil leaked from the gap can flow into the oil drainage cavity 15. The oil drain chamber 15 is communicated to the oil drain port 10 provided on the right side of the casing through an oil drain oil passage 13 in the lower part of the casing. Since all the chambers of the hydraulic system are filled with hydraulic oil during operation, the oil drain chamber 15 is not necessarily located at the lower side, and only needs to be communicated with the gap capable of contacting with the splitter plate 7 and the compensating disc 19.

As shown in fig. 6, a first oil port 23 and a second oil port 22 are also provided on the right side of the housing, the first oil port 23 is communicated to a gap between the right side of the second joint 19-2 of the compensating disc and the housing 9 through a first oil passage 24, and the second oil port 22 is communicated to the central oil chamber 12 through a second oil passage 21. The oil drain port 10, the first oil port 23 and the second oil port 22 are all arranged on the right side of the shell 9, the oil drain oil path 13 is communicated to the oil drain port 10, two branches are branched and respectively connected to the first oil port 23 and the second oil port 22, and the check valves 20 are installed on the two branches.

As shown in fig. 1, 7 and 8, the first and

second ports

23 and 22 are connected to a hydraulic oil source during operation. When the first oil port 23 is an oil inlet, hydraulic oil enters a gap between the second section 19-2 of the compensation disc and the shell 9 through the first oil passage channel 24, enters a flow distribution hole through the compensation oil through hole 16 and the flow distribution oil through hole 17, enters a working oil cavity between the outer rotor 5 and the inner rotor 3 after flow distribution, and is used as high-pressure oil to drive the outer rotor 5 to rotate, so that the whole rotating part rotates around the axis of the motor under the action of the bearing 14; due to the working principle of the cycloid motor, the high-pressure cavity which completes work is replaced by the low-pressure cavity, hydraulic oil flows into the central oil cavity 12 after flow distribution and flows out of the second oil port 22 through the second oil passage 21, at the moment, the second oil port 22 is an oil return port, and the central oil cavity 12 is the low-pressure cavity. On the other hand, because of the relative rotational movement between the compensating flow distribution plate 7 and the compensating disc 19, the hydraulic oil leaks out from the gap between the end surface of the compensating oil passage hole 16 and the end surface of the branch oil passage hole 17, flows into the oil drain cavity 15 below, and flows out from the oil drain port 10 through the oil drain oil passage 13. Since the hydraulic oil sealed by the hydraulic shaft seal 5 is also the leaked hydraulic oil, the pressure at the hydraulic shaft seal 5 can be reduced, so that the hydraulic oil seal 5 does not need to bear high pressure.

When the second oil port 22 is an oil inlet, the hydraulic oil flows into the central oil chamber 12 through the second oil passage 21, flows into the working oil chamber for doing work after flow distribution, flows into the compensation oil through hole 16 through flow distribution after doing work, and flows out of the first oil port 23 through the first oil passage 24. At this time, the compensation oil through hole 16 and the branch oil through hole 17 are both low-pressure passages, so that little hydraulic oil leaks from the gap, the hydraulic shaft seal 5 does not need to bear high pressure, and the pressure in the oil leakage cavity 15 is also very small at this time.

Normally, the drain port 10 is connected to a tank, and hydraulic oil flowing out of the drain port is recovered. And part of the time, the drain port 10 can be sealed by using a plug, at the moment, the one-way valve 20 on one side of the oil return port can be opened due to the pressure difference between the hydraulic oil in the drain oil path 13 and the hydraulic oil on one side of the oil return port, so that the drain oil path is communicated with the oil return port, the hydraulic oil in the drain cavity can flow back through the oil return port, and the effect of reducing pressure can be achieved.

The operating principle of the shell-rotating type cycloid motor can refer to the prior art, a tire required to be driven can be mounted on a wheel hub of a rotating part, power output is directly carried out by the rotating part, and the axial length of the motor is effectively shortened. In the shell rotation type cycloid motor, the inner rotor only revolves around the axis in the outer rotor to achieve the effect of the working principle of the cycloid motor with the alternative high-pressure cavity and low-pressure cavity, and the cycloid motor does not rotate, so that the connected spline shaft only swings and does not rotate and does not serve as a power output part.

Claims

1. A shell rotation type cycloidal motor with an oil drainage function comprises a rotating part and a fixing part, wherein one end of the rotating part is sleeved outside the fixing part and is rotatably connected with the fixing part, the inside of the rotating part is connected with the fixing part in a matching way, and a hydraulic shaft seal is arranged at the matching connection position of the fixing part and the rotating part;

also comprises a spline shaft, one end of the spline shaft extends into the rotating part and is connected with the rotating part, the other end of the spline shaft extends into the fixing part and is connected with the fixing part,

still including draining the oil pocket, the periphery side of fixed part and rotating part cooperation junction is located in the draining chamber, drain the oil pocket with fixed part and rotating part cooperation junction intercommunication, still be equipped with the draining mouth on the fixed part, the draining mouth passes through draining oil circuit and draining chamber intercommunication.

2. The shell-turn gerotor motor with oil drainage of claim 1, wherein the rotating part comprises a front cover, an outer rotor, a port plate and a hub, all of which are connected in sequence, and the front cover, the outer rotor, the port plate and the hub are all rotatable synchronously about an axis;

the inner rotor is arranged in the outer rotor, the inner rotor, the outer rotor and the valve plate are matched to form a working oil cavity, and one end of the spline shaft is matched and connected with the inner rotor;

the fixing part comprises a shell, a central oil cavity is arranged in the shell and is communicated with the working oil cavity through a valve plate, the fixing part also comprises a spline sleeve, the spline sleeve is arranged in the central oil cavity, and one end of the spline shaft is in fit connection with the spline sleeve;

the wheel hub sleeve is arranged on the outer side of the shell and is rotatably connected with the shell;

the shell is provided with a first oil port and a second oil port, the first oil port is communicated with the working oil cavity through the flow distribution plate, and the second oil port is communicated with the central oil cavity.

3. The shell-rotation type cycloid motor with the oil draining function of claim 2 further comprises a compensation disc, wherein the compensation disc is arranged in the central oil cavity, the spline shaft penetrates through the compensation disc, one end of the compensation disc is connected with the shell, and the other end of the compensation disc is connected with the port plate in a matched mode;

and a plurality of compensation oil through holes are formed in the compensation disc, one end of each compensation oil through hole is communicated with the first oil port, and the other end of each compensation oil through hole is communicated with the working oil cavity through the flow distribution disc.

4. The shell-and-turn gerotor motor with oil draining function as claimed in claim 3, wherein the port plate is a multi-piece composite port plate, and a plurality of flow distribution holes are arranged on the multi-piece composite port plate and are in fit communication with the working oil chamber.

5. The shell-rotation type gerotor motor with the oil draining function as claimed in claim 4, wherein one end of the multiple combined type port plates is further provided with a splitter plate, one side of the splitter plate is connected with the multiple combined type port plates, the center part of the other side of the splitter plate is provided with a protruding end, and the protruding end extends into the shell and is connected with the compensation plate in a matching manner;

the flow distribution plate is provided with a flow distribution oil through hole, one end of the flow distribution oil through hole is communicated with the flow distribution hole, and the other end of the flow distribution oil through hole is communicated with the compensation oil through hole;

the hydraulic shaft sleeve is arranged on the outer side of the protruding end.

6. The shell-rotation type gerotor motor with the oil draining function as claimed in claim 5, wherein the oil draining cavity is formed in the shell body on the outer peripheral side of the compensating disc, and the oil draining cavity is communicated with the compensating oil through hole and the shunting oil through hole through a matching connection part of the compensating disc and the port plate.

7. The shell-rotation type gerotor motor with the oil draining function as claimed in claim 2, wherein the first oil port and the second oil port are respectively communicated with an oil draining oil path through a one-way valve.

8. The shell-turn gerotor motor with oil draining function as claimed in claim 7, wherein the oil drain is provided with a detachable oil drain plug.