CN114087120A

CN114087120A - Integral type back pressure resistant cycloid hydraulic motor structure

Info

Publication number: CN114087120A
Application number: CN202111595566.XA
Authority: CN
Inventors: 郭福光; 化金明; 仲崇成; 孙滨; 郑凯
Original assignee: Shandong Rnomac Hydraulic Machinery Co ltd
Current assignee: Shandong Rnomac Hydraulic Machinery Co ltd
Priority date: 2021-12-23
Filing date: 2021-12-23
Publication date: 2022-02-25

Abstract

The invention relates to an integral back pressure resistant cycloid hydraulic motor structure, and belongs to the field of hydraulic motors. Its technical scheme does, an integral resistant back pressure cycloid hydraulic motor structure, including casing and stator rotor subassembly, install the output shaft in the casing, the casing is made for integrated into one piece, the inner chamber diameter of casing and the diameter looks adaptation of output shaft transmission portion, the one end of casing forms the baffle portion, the center of baffle portion is equipped with the baffle hole, the aperture in baffle hole and the diameter looks adaptation of output shaft output portion, transmission portion is located inside the casing, the output portion wears out the casing through the baffle hole, stator rotor subassembly sets up the one end of keeping away from the baffle portion at the casing. The invention has the advantages that the shell is integrally formed, and the baffle part of the shell is used as the front end cover, thereby greatly improving the strength of the shell, thoroughly eliminating the problem that the front end cover is easy to leak oil and oil, and meeting the working requirements of high back pressure such as series connection of hydraulic motors; meanwhile, the assembly difficulty is reduced, and the manufacturing and the use are more convenient.

Description

Integral type back pressure resistant cycloid hydraulic motor structure

Technical Field

The invention relates to the field of hydraulic motors, in particular to an integral back pressure resistant cycloid hydraulic motor structure.

Background

The cycloid hydraulic motor is widely applied to the fields of engineering machinery, agricultural machinery, fishery machinery and the like due to the characteristics of simple structure, small volume, wide rotating speed range, large torque and the like. Gerotor hydraulic motors belong to devices that convert hydraulic energy into mechanical energy.

The current BM series motor shell structure is shown in fig. 1 and fig. 2, the front end of the shell is provided with a front cover through bolts, the output shaft of the motor passes through the front cover, the front cover of the cycloid motor and the shell are installed in a bolt connection way at the present stage, when the BM series motor is installed in series with a large back pressure, the front cover is easy to damage due to the low structural strength of the sinking platform of the front cover, and the oil leakage or oil leakage phenomenon is caused.

Disclosure of Invention

The invention provides an integral back pressure-resistant cycloid hydraulic motor structure, aiming at the problem that the existing motor is easy to damage oil leakage and oil leakage under high back pressure.

In order to solve the problems, the technical scheme adopted by the invention is that the integral back pressure resistant cycloid hydraulic motor structure comprises a shell and a stator and rotor assembly, an output shaft is installed in the shell and comprises a transmission part and an output part, the transmission part and the output part are coaxially arranged, the diameter of the transmission part is larger than that of the output part, the shell is manufactured in an integrated mode, a cylindrical cavity is formed inside the shell, the diameter of an inner cavity of the shell is matched with that of the transmission part, a baffle part is formed at one end of the shell, a baffle hole is formed in the center of the baffle part, the aperture of the baffle hole is matched with that of the output part, the transmission part is located inside the shell, the output part penetrates out of the shell through the baffle hole, and the stator and rotor assembly is arranged at one end of the shell, which is far away from the baffle part. The front shell is integrally formed, and the baffle part of the shell is used as a front end cover, so that the strength of the shell is greatly improved, the back pressure resistance is improved, the problem that the front end cover is easy to leak oil and oil under high back pressure is greatly avoided, and the working requirements of high back pressure such as series connection of hydraulic motors can be met; greatly reduced the processing degree of difficulty, be convenient for more make and use, reduced the assembly degree of difficulty simultaneously.

Preferably, the inner wall of the casing is circumferentially provided with a casing oil distribution ring groove, the outer circumferential surface of the transmission part is circumferentially provided with an on-shaft oil distribution ring groove, the outer wall of the casing is provided with two oil inlet/return ports which are communicated to the inner cavity of the casing, the two oil inlet/return ports are respectively arranged at positions corresponding to the on-shaft oil distribution ring groove and the casing oil distribution ring groove, and the casing oil distribution ring groove and the on-shaft oil distribution ring groove are used for supplying and discharging oil of the stator and rotor assembly. The oil distribution ring groove is arranged on the shell, so that the structure of the output shaft is simplified, the processing process of the output shaft is further simplified, the shell and the oil distribution ring groove are integrally formed when the shell is manufactured, the processing is simpler and more convenient, and the overall cost is reduced; meanwhile, the diameter change of the output shaft is reduced, and the strength of the output shaft is improved.

Preferably, the outer circular surface of the transmission part is also provided with a certain number of first on-shaft oil distribution straight grooves and second on-shaft oil distribution straight grooves, and the number of the first on-shaft oil distribution straight grooves is equal to that of the second on-shaft oil distribution straight grooves; a certain number of shell oil distribution holes are uniformly formed in the side wall of the shell along the circumferential direction, one end of each shell oil distribution hole is communicated to the inner cavity of the shell, the other end of each shell oil distribution hole is communicated to the fixed rotor assembly, the axial position of the oil distribution straight groove on the first shaft is arranged between the shell oil distribution ring groove and the shell oil distribution holes, and the oil distribution straight groove on the first shaft can be communicated with the shell oil distribution ring groove and the shell oil distribution holes; one end of the oil distribution straight groove on the second shaft is connected with the oil distribution ring groove on the shaft, the axial position of the other end of the oil distribution straight groove on the second shaft corresponds to the oil distribution hole of the shell, and the oil distribution straight groove on the second shaft can be communicated with the oil distribution ring groove on the shaft and the oil distribution hole of the shell. The oil duct is integrated into one piece on the casing, reduces the holistic production processing degree of difficulty of motor, improves work efficiency.

Preferably, the shell oil distribution hole is a counter bore arranged on the end face of the shell, the axial direction of the shell oil distribution hole is parallel to the output shaft, and the side wall of the bottom of the counter bore is provided with a slot communicated to the inner cavity of the shell. Is convenient for the process design of integral molding.

Preferably, a casing one-way oil duct is further arranged inside the side wall of the casing, one end of the casing one-way oil duct is communicated to the stator and rotor assembly, the other end of the casing one-way oil duct is communicated with the casing oil distribution ring groove or the on-shaft oil distribution ring groove, a one-way valve is installed at one end of the casing one-way oil duct, which is connected with the stator and rotor assembly, and the conduction direction of the one-way valve is the direction of the stator and rotor assembly to the casing. The hydraulic oil that leaks in enters into the inside cavity of motor housing, realizes the lubrication and the cooling to the output shaft.

Preferably, the baffle hole is provided with a thrust bearing, the output part penetrates through the thrust bearing, one end face of the thrust bearing is abutted against the baffle part, and the other end face of the thrust bearing is abutted against the end face of the transmission part. Baffle portion of integrative design can bear bigger pressure, and the output shaft can bear bigger axial load, sets up to thrust bearing for the output shaft can smoothly rotate when axial load is big, and the bearing can not damage simultaneously.

Preferably, a transmission shaft mounting hole is formed in the end face, far away from the output portion, of the transmission portion, a transmission shaft is mounted in the transmission shaft mounting hole, one end of the transmission shaft is connected with the transmission portion, the other end of the transmission shaft is connected with a rotor in the stator and rotor assembly, a small shaft hole is formed in the bottom of the transmission portion mounting hole, a side hole is formed in the inner side wall of the small shaft hole, and the side hole is communicated to the outer circular face of the output portion and corresponds to the position of the thrust bearing. The internal leakage hydraulic oil can lubricate the thrust bearing.

Preferably, the back lid is installed to the terminal surface of stator and rotor subassembly dorsad casing, and the stopper is installed at the center of back lid, and the stopper is arranged in the hole of rotor, and the diameter of stopper is less than the diameter of transmission shaft. So that the transmission shaft is not clamped due to the contact with the rear cover when the axial load is large.

Preferably, the housing is integrally cast. The oil way integrated casting die is convenient to manufacture, can easily complete the integrated casting of the oil way through the die design, and is low in mass production cost.

According to the technical scheme, the invention has the advantages that: the front shell of the hydraulic motor is provided with an integrally formed baffle part, namely the front cover and the shell are of an integral structure, the structure can bear high back pressure, can completely meet the special requirements under specific working conditions, meets the working condition use requirements of high back pressure of multi-motor series connection, and avoids the phenomena of oil leakage and oil leakage at the front end of the motor; the casing is integrally cast, the oil duct is integrated in the casing and integrally formed by casting, so that the processing is more convenient, the structure of the output shaft is simplified, the strength of the output shaft is improved, the production cost and the production processing difficulty are reduced, and the production efficiency is improved; the motor output shaft can bear higher axial load, the internal lubrication is good, the motor output shaft can smoothly rotate under high load, the use performance is good, the service life is long, and the application field of the cycloid motor is increased.

Drawings

In order to more clearly illustrate the technical solution of the present invention, the drawings used in the description will be briefly introduced, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained based on these drawings without creative efforts.

Fig. 1 is a schematic structural view of a conventional BM-series hydraulic motor.

Fig. 2 is a front end view of a conventional BM-series hydraulic motor.

Fig. 3 is a schematic structural diagram of an embodiment of the present invention.

Fig. 4 is a cross-sectional view of an embodiment of the present invention.

In the figure: 01. the oil-gas separator comprises a front end cover, a shell, 1-1 baffle parts, 2 output shafts, 2-1 transmission parts, 2-2 output parts, 3 shell oil distribution ring grooves, 4 shaft oil distribution ring grooves, 5-1 first shaft oil distribution straight grooves, 5-2 second shaft oil distribution straight grooves, 6 shell oil distribution holes, 7 shell one-way oil passages, 8 one-way valves, 9 thrust bearings, 10 transmission shafts, 11 shaft small holes, 12 side holes, 13 rear covers, 14 limiting blocks, 15 stator rotor assemblies, 16 partition plates, 17 rear cover bolts, 18 bolt holes, 19 oil seals, 20 dust rings and 21 oil inlet/return ports.

Detailed Description

In order to make the objects, features and advantages of the present invention more obvious and understandable, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings in the present embodiment, and it is apparent that the embodiments described below are only a part of embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the scope of protection of this patent.

As shown in fig. 3 and 4, an integral back pressure resistant cycloid hydraulic motor structure comprises a housing 1, the housing 1 is integrally formed by a casting process, the interior of the housing 1 is a cylindrical cavity, one end of the housing 1 is cast to form a baffle portion 1-1, a baffle hole is formed in the center of the baffle portion 1-1, the other end of the housing 1 is an open end face, a stator-rotor assembly 15 is installed on the open end face, a baffle plate 16 is arranged between the stator-rotor assembly 15 and the housing 1, an outer ring stator of the stator-rotor assembly 15 is fixedly connected with the housing 1, a rear cover 13 is installed on the end face, opposite to the housing 1, of the stator-rotor assembly 15, a certain number of rear cover bolts 17 are installed on the rear end face of the rear cover 13, and the housing 1, the baffle plate 16, the stator-rotor assembly 15 and the rear cover 13 are connected into a whole; an output shaft 2 is arranged in a shell 1, the output shaft 2 comprises an output part 2-2 with a smaller diameter and a transmission part 2-1 with a larger diameter, the transmission part 2-1 rotates along with a rotor in a stator-rotor assembly and transmits torque, the output part 2-2 penetrates out of the shell 1 to be connected with an external load and drive the load, the transmission part 2-1 and the output part 2-2 are coaxially arranged, the aperture of a baffle hole is matched with the diameter of the output part 2-2, the transmission part 2-1 is positioned in the shell 1, the output part 2-2 penetrates out of the shell 1 through the baffle hole, a dust ring 20 and an oil seal 19 are arranged on the inner circular surface of the baffle hole, the dust ring 20 is close to the outer end surface of the baffle part 1-1, the oil seal 19 is close to the inner cavity of the shell 1, and a thrust bearing 9 is arranged between the transition end surface between the transmission part 2-1 and the output part 2-2 and the baffle part 1-1, the output part 2-2 penetrates through a thrust bearing 9, one end face of the thrust bearing 9 is abutted to a baffle part 1-1, the other end face of the thrust bearing is abutted to the end face of a transmission part 2-1, one end, far away from the output part 2-2, of the transmission part 2-1 is provided with a transmission shaft mounting hole, a transmission shaft 10 is installed in the transmission shaft mounting hole and used for transmitting the torque of a rotor to the transmission part 2-1 and further driving the output shaft 2 to integrally rotate, one end of the transmission shaft 10 is connected with the transmission part 2-1, the other end of the transmission shaft 10 is connected with the rotor in a stator and rotor assembly, a shaft small hole 11 is formed in the bottom of the transmission part mounting hole, a side hole 12 is formed in the inner side wall of the shaft small hole 11, the side hole 12 is communicated to the outer circular face of the output part 2-2 and corresponds to the position of the thrust bearing 9, hydraulic oil which is internally leaked in the stator and rotor assembly passes through the transmission shaft mounting hole, The small shaft hole and the side hole reach the thrust bearing to lubricate the thrust bearing, a limiting block 14 is arranged in the center of one surface of the rear cover 13 facing the stator and rotor assembly and is positioned in an inner hole of the rotor, the diameter of the limiting block is smaller than that of the transmission shaft, when the output shaft is subjected to larger axial load, the limiting block supports against the transmission shaft, the rotor and the rear cover are prevented from being contacted with each other at the same time, and the rotation smoothness is improved;

among this hydraulic motor, hydraulic pressure oil circuit most part is integrated on the casing, with casing integrated into one piece cast molding: a shell oil distribution ring groove 3 is formed in the inner wall of the shell 1 along the circumferential direction, an on-shaft oil distribution ring groove 4 is formed in the outer circumferential surface of the transmission part 2-1 along the circumferential direction, two oil inlet/return ports 21 are formed in the outer wall of the shell 1, bolt holes 18 used for fixing an external oil way pipeline are formed in two sides of each oil inlet/return port 21 respectively, each oil inlet/return port 21 is communicated with the inner cavity of the shell 1, and the two oil inlet/return ports 21 are arranged at positions corresponding to the on-shaft oil distribution ring groove 4 and the shell oil distribution ring groove 3 respectively and are communicated with the corresponding oil distribution ring grooves; the outer circular surface of the transmission part 2-1 is also provided with six first on-shaft oil distribution straight grooves 5-1 and six second on-shaft oil distribution straight grooves 5-2, in the circumferential direction of the transmission part 2-1, the first on-shaft oil distribution straight grooves 5-1 are arranged in the range of a semicircle at one side of the transmission part 2-1, and the second on-shaft oil distribution straight grooves 5-2 are arranged in the range of a semicircle at the opposite side; the inner side wall of the shell 1 is uniformly provided with 7 shell oil distribution holes 6 along the circumferential direction, one end of each shell oil distribution hole 6 is communicated to the inner cavity of the shell 1, the other end of each shell oil distribution hole 6 is communicated to the stator and rotor assembly, specifically, one end of each shell oil distribution hole close to the stator and rotor assembly is positioned at the meshing line of a stator and a rotor in the stator and rotor assembly 15, so that oil distribution of a high-pressure cavity and a low-pressure cavity is realized, the axial position of an oil distribution straight groove 5-1 on a first shaft is arranged between the shell oil distribution ring groove 3 and the shell oil distribution holes, and the oil distribution straight groove 5-1 on the first shaft can communicate the shell oil distribution ring groove 3 with the shell oil distribution holes 6; one end of a straight oil distribution groove 5-2 on the second shaft is connected with an oil distribution ring groove 4 on the shaft, the axial position of the other end corresponds to an oil distribution hole 6 of the shell, the straight oil distribution groove 5-2 on the second shaft can be communicated with the oil distribution ring groove on the shaft and the oil distribution hole 6 of the shell, the oil distribution hole 6 of the shell is a counter bore arranged on the end surface of the shell 1, the axial direction of the oil distribution hole 6 of the shell is parallel to the output shaft 2, and the side wall of the bottom of the counter bore is provided with a slot communicated with the inner cavity of the shell 1; the inside one-way oil duct 7 of casing that still is equipped with of lateral wall of casing 1, the one-way oil duct 7 one end of casing communicates to the stator-rotor subassembly, the other end communicates with casing oil distribution ring groove 3 or epaxial oil distribution ring groove 4, check valve 8 is installed to the one end that casing one-way oil duct 7 is connected with the stator-rotor subassembly, the direction that switches on of check valve 8 is the direction that the stator-rotor subassembly accesss to casing 1, the hydraulic oil that leaks in flows back to the casing inner chamber, lubricate the output shaft and cool down, the position that corresponds casing one-way oil duct 7 and casing oil distribution hole on baffle 16 all is equipped with the oil through-hole.

When the hydraulic motor is in oil distribution work, one of the two oil inlet/return ports is used as a high-pressure oil inlet, the other oil inlet/return port is used as a low-pressure oil return port, the oil inlet is communicated with the shell oil distribution ring groove 3, the oil return port is communicated with the shaft oil distribution ring groove 4, hydraulic oil enters the shell oil distribution ring groove 3 through the oil inlet, enters the corresponding shell oil distribution hole through the first shaft oil distribution straight groove 5-1 and further enters the stator and rotor assembly to form a high-pressure oil cavity, and the rotor is pushed to rotate; the low-pressure oil enters the oil distribution ring groove 4 on the shaft through the oil distribution straight groove 5-2 on the second shaft and is discharged from the oil return port through the shell oil distribution hole communicated with the oil distribution straight groove 5-2 on the second shaft; the rotor drives the output shaft to rotate through the transmission shaft, meanwhile, the oil distribution straight groove on the first shaft and the oil distribution straight groove on the second shaft also synchronously rotate, and the high-pressure oil cavity and the low-pressure oil cavity in the stator-rotor component synchronously change, so that continuous rotation output is realized; the forward and reverse rotation switching can be realized by changing the flow direction of the hydraulic oil of the two oil inlet/return ports.

The above embodiment shows that the beneficial effects of the invention are as follows: the front shell of the hydraulic motor is provided with an integrally formed baffle part, namely the front cover and the shell are of an integral structure, the structure can bear high back pressure, can completely meet special requirements under specific working conditions, meets the working condition use requirements of high back pressure of multiple motors in series connection, and avoids the phenomena of oil leakage and oil leakage at the front end of the motor; the casing is integrally cast, the oil duct is integrated in the casing and integrally formed by casting, so that the processing is more convenient, the structure of the output shaft is simplified, the strength of the output shaft is improved, the production cost and the production processing difficulty are reduced, and the production efficiency is improved; the motor output shaft can bear higher axial load, the internal lubrication is good, the motor output shaft can smoothly rotate under high load, the use performance is good, the service life is long, and the application field of the cycloid motor is increased.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An integral back pressure resistant cycloid hydraulic motor structure is characterized by comprising a shell (1) and a stator-rotor assembly (15), wherein an output shaft (2) is installed in the shell (1), the output shaft (2) comprises a transmission part (2-1) and an output part (2-2), the transmission part (2-1) and the output part (2-2) are coaxially arranged, the diameter of the transmission part (2-1) is larger than that of the output part (2-2), the shell (1) is integrally manufactured, a cylindrical cavity is formed inside the shell (1), the diameter of an inner cavity of the shell (1) is matched with that of the transmission part (2-1), a baffle part (1-1) is formed at one end of the shell (1), a baffle hole is formed in the center of the baffle part (1-1), and the aperture of the baffle hole is matched with that of the output part (2-2), the transmission part (2-1) is positioned in the shell (1), the output part (2-2) penetrates out of the shell (1) through the baffle hole, and the stator-rotor assembly (15) is arranged at one end, far away from the baffle part (1-1), of the shell (1).

2. The integral back pressure resistant cycloid hydraulic motor structure of claim 1, wherein the inner wall of the housing (1) is circumferentially provided with a housing oil distribution ring groove (3), the outer circumferential surface of the transmission part (2-1) is circumferentially provided with an on-shaft oil distribution ring groove (4), the outer wall of the housing (1) is provided with two oil inlet/return ports (21), the oil inlet/return ports (21) are communicated with the inner cavity of the housing (1), the two oil inlet/return ports (21) are respectively arranged at positions corresponding to the on-shaft oil distribution ring groove (4) and the housing oil distribution ring groove (3), and the housing oil distribution ring groove (3) and the on-shaft oil distribution ring groove (4) are used for oil supply and discharge of the stator assembly (15).

3. The integral back pressure resistant cycloid hydraulic motor structure of claim 2 wherein the outer circumferential surface of the transmission part (2-1) is further provided with a certain number of first on-axis oil distribution straight grooves (5-1) and second on-axis oil distribution straight grooves (5-2), the number of the first on-axis oil distribution straight grooves (5-1) and the number of the second on-axis oil distribution straight grooves (5-2) are equal; a certain number of shell oil distribution holes (6) are formed in the inner portion of the side wall of the shell (1) along the circumferential direction, one end of each shell oil distribution hole (6) is communicated with the inner cavity of the shell (1), the other end of each shell oil distribution hole (6) is communicated with the fixed rotor assembly (15), the axial position of the first-shaft oil distribution straight groove (5-1) is arranged between the shell oil distribution ring groove (3) and the shell oil distribution holes, and the first-shaft oil distribution straight groove (5-1) can communicate the shell oil distribution ring groove (3) and the shell oil distribution holes (6); one end of the second shaft oil distribution straight groove (5-2) is connected with the shaft oil distribution ring groove (4), the axial position of the other end of the second shaft oil distribution straight groove corresponds to the shell oil distribution hole (6), and the second shaft oil distribution straight groove (5-2) can be communicated with the shaft oil distribution ring groove (4) and the shell oil distribution hole (6).

4. The integral back pressure resistant cycloid hydraulic motor structure of claim 3, characterized in that the housing oil distribution hole (6) is a counter bore arranged on the end face of the housing (1), the axial direction of the housing oil distribution hole (6) is parallel to the output shaft (2), and the side wall of the bottom of the counter bore is provided with a slot communicated to the inner cavity of the housing (1).

5. The integral back pressure resistant cycloid hydraulic motor structure as claimed in claim 2, wherein a housing one-way oil passage (7) is further provided inside the side wall of the housing (1), one end of the housing one-way oil passage (7) is communicated to the stator and rotor assembly (15), the other end of the housing one-way oil passage is communicated with the housing oil distribution ring groove (3) or the on-shaft oil distribution ring groove (4), a one-way valve (8) is installed at one end of the housing one-way oil passage (7) connected with the stator and rotor assembly (15), and the conduction direction of the one-way valve (8) is the direction of the stator and rotor assembly (15) to the housing (1).

6. The integrated back pressure resistant gerotor hydraulic motor structure as claimed in any one of claims 1-5, characterized in that a thrust bearing (9) is arranged at the baffle hole, the output part (2-2) passes through the thrust bearing (9), one end surface of the thrust bearing (9) abuts against the baffle part (1-1), and the other end surface abuts against the end surface of the transmission part (2-1).

7. The integral back pressure resistant cycloid hydraulic motor structure of claim 6, wherein the end face of the transmission part (2-1) far away from the output part (2-2) is provided with a transmission shaft mounting hole, a transmission shaft (10) is mounted in the transmission shaft mounting hole, one end of the transmission shaft (10) is connected with the transmission part (2-1), the other end of the transmission shaft (10) is connected with a rotor in the stator-rotor assembly (15), the bottom of the transmission part mounting hole is provided with a shaft small hole (11), the inner side wall of the shaft small hole (11) is provided with a side hole (12), and the side hole (12) is communicated to the outer circular surface of the output part (2-2) and corresponds to the position of the thrust bearing (9).

8. The integral back pressure resistant cycloid hydraulic motor structure of claim 7, wherein the end surface of the stator-rotor assembly (15) opposite to the housing (1) is provided with a rear cover (13), the center of the rear cover (13) is provided with a limit block (14), the limit block (14) is positioned in the inner hole of the rotor, and the diameter of the limit block is smaller than that of the transmission shaft (10).

9. The integrated back pressure resistant gerotor hydraulic motor structure of any one of claims 1-5, characterized in that the housing (1) is integrally cast.