CN202520499U

CN202520499U - Plunger-type motor pump

Info

Publication number: CN202520499U
Application number: CN2012201291176U
Authority: CN
Inventors: 朱碧海; 贺小峰; 刘银水; 朱玉泉; 吴肖宇
Original assignee: Huazhong University of Science and Technology
Current assignee: Huazhong University of Science and Technology
Priority date: 2012-03-30
Filing date: 2012-03-30
Publication date: 2012-11-07
Anticipated expiration: 2022-03-30

Abstract

The utility model discloses a plunger-type motor pump, belongs to a plunger pump, and solves the problems that the strength of a cylinder body of the conventional plunger-type motor pump is weak and the whole power density is low. According to the plunger-type motor pump, a motor stator is arranged in a shell; two ends of a cylinder body are respectively supported at the center of left and right end covers; a motor rotor is sleeved and fixedly connected with a boss in the middle of the cylinder body; N plunger cavities are formed on left and right end faces of the boss of the cylinder body respectively; a plunger piston shoe assembly is arranged in each plunger cavity; suction and discharge valve assemblies corresponding to the plunger piston shoe assemblies are arranged on the boss of the cylinder body respectively; left and right swash plates are tightly fastened to the inner sides of the left and right end covers respectively, and plate surfaces of the left and right swash plates are parallel; every two coaxial plunger piston shoe assemblies are supported by a support rod; and piston shoe heads at two ends are pressed on the plate surfaces of the left and right swash plates respectively. According to the plunger-type motor pump, a reaction thrust generated between the plunger piston shoe assemblies at two ends and the swash plates and an internal hydraulic acting force of the cylinder body are transferred by the support rod, so the number of parts is decreased, the strength of a pump is improved and the space utilization rate of the cylinder body is improved integrally.

Description

A kind of plunger type electric-motor pump

Technical field

The utility model belongs to plunger pump, particularly a kind of plunger type electric-motor pump.

Background technique

Electric-motor pump is a kind of new type hydraulic power unit, and it is combined as integral body with motor and pump, and is simple and compact for structure, efficient is high, amount of leakage is few, noise is low." 3 stops " power unit that connects than in the past coupling; Electric-motor pump structure level of integration is very high; And volume size has very greatly on basis in the past and dwindles, and very is easy to carry, and can directly be used for the very high special occasions of the narrow and small environmental requirement in many spaces.

The level of integration of electric-motor pump own is very high; It also makes its inner space very nervous when bringing the advantage of compact structure; When electric-motor pump is worked; For the phase mutual noninterference between the part inside guaranteeing and reliable and stable its function of realization, in the setting of its structural parameter, can run into a lot of problem, especially electric-motor pump overall power density and pump integral rigidity, intensity balances between the two that are difficult to solve and choose; Often in order to guarantee the electric-motor pump integral intensity; The designer can only select to sacrifice the specific power of electric-motor pump part, so how can effectively optimize the electric-motor pump internal structure, the specific power that can effectively improve the electric-motor pump of compact structure is the biggest problem that electric-motor pump development now faces.

The application number that the claimant submits to is 201010103656.8 " diclinic moushroom valve ported axial plunger formula water hydraulic canned motorpump "; Comprise shell, motor stator, rotor, cylinder body, plunger piston slippery boots assembly, backhaul dish, ball pivot, swash plate and flow-distributing valve assembly; Symmetrical placement two swash plates in the cylinder body left and right sides; Such design can effectively improve flow; But because the spatial limitation of both sides backhaul dish and spherical hinge structure makes that the pump cylinder support zone diameter of axle is less than normal, and do not produce cavitation erosion when guaranteeing the whole flow of pump, the aperture of its water sucking mouth and setting-out mouth can not be too little; So make the wall thickness dimension at cylinder body two end supports position greatly cut down, influenced the intensity of pump cylinder structure position; Moreover, can not becoming of water sucking mouth size greatly also determined the whole flow of pump can not do greatly, hinders the raising of electric-motor pump specific power, reduced the development space of electric-motor pump to a great extent.

Summary of the invention

The utility model provides a kind of plunger type electric-motor pump, solves the problem that cylinder strength is on the weak side and overall power density is not high of existing plunger type electric-motor pump.

A kind of plunger type electric-motor pump that the utility model provided comprises shell, motor stator, rotor, cylinder body, a 2N plunger piston slippery boots assembly, left swash plate, right swash plate and 2N suction valve assembly and 2N delivery valve assembly, and N is 3～11 odd number; Said shell, motor stator and rotor are cylindrical shape; Motor stator is assemblied in the shell, and left end cap and right end cap pass through bolt respectively in said shell right ends, and said cylinder body is the step axle with middle part boss; Its two ends are supported on left end cap center and right end cap center by tapered roller bearing respectively; Left bearing lid is fastened on the left end cap center through screw, and the tapered roller bearing of left end is held out against in the cylinder body left end, and left bearing lid center has oil through; Cylinder body middle part projection section is with rotor and is connected; It is inner and have air gap between the two that rotor is positioned at motor stator, and cylinder body, rotor, motor stator three are coaxial, and the cylinder body longitudinal center line is as the central rotating shaft of rotor;

The left and right two ends of said cylinder body have axial inlet port and oil drain out; The left and right end face axial of cylinder body boss has the plunger cavity along the equally distributed N of circumference; The coaxial one by one correspondence of N plunger cavity of the left and right end face of cylinder body boss, and through first hole link; Be inlaid with plunger bushing in each plunger cavity, plunger bushing is built-in with the plunger piston slippery boots assembly of Spielpassung; Said cylinder body boss radially has N left suction chamber, a N left side extrudes chamber, a N right suction chamber, a N right chamber that extrudes, and N left suction chamber, a N left side extrude chamber, a N right suction chamber and N the right coaxial one by one correspondence in chamber that extrudes; N left suction chamber position is corresponding with N plunger cavity position of cylinder body boss left side respectively, and is communicated with plunger cavity and inlet port; A N left side extrudes the chamber respectively through the second hole link oil drain out; N right suction chamber is respectively through the 3rd hole link inlet port; N the right chamber that extrudes is communicated with plunger cavity and oil drain out respectively; In N left suction chamber and N right suction chamber suction valve assembly is housed respectively, extrusion chamber, a N left side and N right the extrusion in the chamber are equipped with the delivery valve assembly respectively; It is characterized in that:

Left end cap inboard with the right end cap inboard respectively with left swash plate, that right swash plate passes through locating stud is fastening, the center of said left swash plate and right swash plate is coaxial, card is parallel;

Hold mutually through the strut in said first duct between the plunger piston slippery boots assembly of per two the coaxial correspondences of the left and right end face of said cylinder body boss; It is right to constitute plunger-piston shoes, and each plunger-piston shoes is pressed on respectively on the card of left swash plate and right swash plate two ends piston shoes head;

Said cylinder body right-hand member stretches out right end cap, adopts the oil drain out of screw plug closed cylinder right side, and cylinder body right-hand member side has the radially oil drainage hole of the said oil drain out of UNICOM;

The right bearing lid is fastened on the right end cap outer side center through screw, and tapered roller bearing is held in the cylinder body right-hand member, and said right bearing lid is the cylindrical shape of bottom lock; The inside is equipped with the end cover; Is limited the Cock screw that passes right bearing lid and to rotate in a circumferential direction, the end cover is the inwardly protruded cylinder of last lower limb, and bore cooperates with said cylinder body right-hand member external diameter about it; Be placed in said cylinder body right-hand member, end cover one end is by the circlip axial limiting that is embedded in the right bearing lid; The radially oil drainage hole position of said right bearing lid and corresponding said cylinder body right-hand member side, end cover side has oil outlet; Hydraulic oil is from the oil outlet connection extraneous hydraulic system of side of cylinder block oil drainage hole through end cover and right bearing lid.

Described plunger type electric-motor pump is characterized in that:

Said left suction chamber, right suction chamber shape are identical, are the secondary shoulder hole, and the following hole UNICOM less by the bigger last hole of internal diameter and internal diameter constitutes; Said suction valve assembly is made up of spool, spring, valve seat and bonnet, and spool, spring, valve seat and bonnet are inserted in the last hole of left suction chamber or right suction chamber in regular turn, and spool is spherical; Be pressed in the place, following hole of left suction chamber or right suction chamber, form valve port, said spring one end withstands spool; The spring the other end withstands valve seat, and valve seat is a ring, has the stepped shaft endoporus; The valve seat top is withstood by bonnet; Said bonnet has the undercut shape cross section, after bonnet is inserted the last hole of left suction chamber or right suction chamber, abdicates the position in first duct; The following hole of N right suction chamber is communicated with inlet port through N the 3rd duct;

A said left side extrudes the chamber, right extrusion cavity shape is identical, is three grades of shoulder holes, and hole, the upper, middle and lower UNICOM of being successively decreased successively by internal diameter constitutes; Said delivery valve assembly is made up of spring, spool and valve gap, and said spring is inserted a left side and extruded in the mesopore in chamber or right extrusion chamber, and an end is by the hole is spacing down; Said spool and valve gap are inserted a left side in regular turn and are extruded chamber or the right last hole that extrudes the chamber; The spool pressing spring the other end, the spool top is withstood by valve gap, and said valve gap has the undercut shape cross section; After valve gap is inserted the last hole in extrusion chamber, a left side or right extrusion chamber, abdicate the position in first duct; The following hole in extrusion chamber, a N left side is communicated with oil drain out through N second duct;

Said second duct and the 3rd duct are the inclination duct, and they are in cylinder interior even distribution alternate with each other, and isolated mutually between second duct and the 3rd duct.

Second duct and the 3rd duct manufacturing process can adopt the method for casting, also can split processing weld in assembling then.

Described plunger type electric-motor pump; Said cylinder body middle part projection section and rotor be connected mode can for: the boss left hand edge has the seam step in the middle part of the said cylinder body; The left side of rotor is withstood spacing by said seam step, the right side of rotor connects through flat key, sunk screw and thrust button are fastening with the right side of cylinder body boss.

Said cylinder body middle part projection section and the rotor mode that is connected also can be: the left and right sides end face of rotor connects through flat key, sunk screw and thrust button are fastening respectively with the left and right sides end face of cylinder body boss.

The utility model working procedure is following: when the motor stator energized; The rotating magnetic field that the motor stator the inside produces produces electromagnetic torque on rotor; Under the effect of electromagnetic torque; The fastening integrative-structure that is connected into of rotor and cylinder body rotates around the cylinder body central axis; Then drive the plunger piston slippery boots assembly that is assemblied in the cylinder body plunger cavity and rotate together, because the parallel spacing of the swash plate assembly of cylinder body both sides limits, a pair of plunger piston slippery boots assembly of cylinder body both sides correspondence is to reciprocating in plunger cavity back and forth under the effect of holding of strut; Cooperate the suction valve assembly be installed in the cylinder body and the periodicity of delivery valve assembly to open and closure simultaneously; Plunger piston slippery boots assembly from the inlet port of cylinder body in the inspiration cylinder body plunger cavity, and then is pressed onto the oil extraction end with the hydraulic oil of high pressure from the oil drain out of cylinder body with hydraulic oil, accomplishes the suction-oil extraction process of electric-motor pump; Be set with the end cover in cylinder body oil extraction splaying; Be enclosed within cylinder body rotary course middle-end and keep motionless under the effect of Cock screw; Rationally control gap amount size makes cylinder body oil extraction section and end inner room form the stable rotation sealing; The high pressure oil that gets into the oil extraction end is because the rotary seal effect that end cover and cylinder body oil extraction end form smoothly in the space through runner inlet end cover in the cylinder body, and drains into extraneous hydraulic system and supply follow-up hydraulic equipment use.

The working medium that adopts in the utility model is not limited to above-mentioned hydraulic oil, can be the medium that water or other hydraulic pressure installation adopt.

Compare with existing diclinic dish hydraulic plunger formula electric-motor pump, the utlity model has following advantage:

1. fully effectively utilized interaction force between cylinder interior hydraulic coupling and the part; Between two plungers of correspondence, introduce strut; Effect through strut passes to a corresponding other end plug with reaction thrust that produces between two ends plunger piston slippery boots assembly and the swash plate and cylinder interior hydraulic action; Impel its return motion, played a kind of effect that impels the plunger backhaul; Thereby saved the backhaul mechanism of pump on the traditional sense, comprised a series of parts such as backhaul dish, ball pivot and retracting spring, reduced the number of pump component from structure; Removed the trouble design of ball pivot simultaneously from; The wall thickness that has guaranteed the pump cylinder supporting section (when the design ball pivot, because pump cylinder two end supports section need be passed parts such as swash plate ball pivot, and is limited to the ball pivot outside diameter within the specific limits; The size that makes the ball pivot center hole to allow is limited; Will certainly make the cylinder body supporting section diameter of axle attenuate, greatly weaken the strength and stiffness of cylinder body), effectively improved the strength and stiffness of cylinder body.

2. greatly improve pump cylinder inner space utilization ratio, no longer received the constraint of a series of backhaul mechanism sizes during owing to the pump cylinder design, made that the inherent design of pump cylinder flow distribution apparatus time space is more sufficient, given structural design bigger performance space.

Description of drawings

Fig. 1 is the utility model embodiment plan view

Fig. 2 (A) is suction valve assembly assembling schematic representation;

Fig. 2 (B) is the left view of Fig. 2 (A);

Fig. 3 (A) is delivery valve assembly assembling schematic representation;

Fig. 3 (B) is the left view of Fig. 3 (A);

Fig. 4 is a cylinder body centre section schematic representation.

Mark among the figure: bolt 1; Left end cap 2; Screw 3; Left bearing lid 4; Tapered roller bearing 5; Locating stud 6; Left side swash plate 7; Shell 8; Plunger piston slippery boots assembly 9; Plunger bushing 10; Cylinder body 11; Suction valve assembly 12; Delivery valve assembly 13; Strut 14; Rotor 15; Motor stator 16; Right end cap 17; Thrust button 18; Right bearing lid 19; Cock screw 20; Screw plug 21; End cover 22; Circlip 23; Right swash plate 24; First duct 25; Second duct 26; The 3rd duct 27; Spool 28; Spring 29; Valve seat 30; Bonnet 31; Valve gap 32.

Embodiment

Below in conjunction with accompanying drawing and embodiment the utility model is further specified.

As shown in Figure 1; The utility model embodiment comprises shell 8, motor stator 16,

rotor

15,11,10 plunger piston slippery boots assemblies 9 of cylinder body, left swash plate 7,

right swash plate

24 and 10

suction valve assemblies

12 and 10 delivery valve assemblies 13; Said shell 8, motor stator 16 and rotor 15 are cylindrical shape; Motor stator 16 is assemblied in the shell 8; Left end cap 2 is fixed in said shell 8 right ends through bolt 1 respectively with right end cap 17, and said cylinder body 11 is for having the step axle of middle part boss, and its two ends are supported on left end cap 2 centers and right end cap 17 centers by tapered roller bearing 5 respectively; Left bearing lid 4 is fastened on left end cap 2 centers through screw 3; The tapered roller bearing 5 of left end is held out against in cylinder body 11 left ends, and left bearing covers 4 centers and has oil through, and cylinder body 11 middle part projection sections are with rotor 15 and are connected; (left and right sides end face of the left and right sides end face of rotor 15 and cylinder body 11 boss is respectively through flat key, sunk screw and 18 fastening connections of thrust button;) rotor 15 is positioned at that motor stator 16 is inner and have air gap between the two, 16 threes are coaxial for cylinder body 11, rotor 15, motor stator, and the cylinder body longitudinal center line is as the central rotating shaft of rotor 15;

Said cylinder body 11 left and right two ends have axial inlet port and oil drain out; The left and right end face axial of cylinder body boss has along equally distributed 10 plunger cavities of circumference; The coaxial one by one correspondence of 10 plunger cavities of the left and right end face of cylinder body boss, and through 25 connections of first duct; Be inlaid with plunger bushing 10 in each plunger cavity, plunger bushing 10 is built-in with the plunger piston slippery boots assembly 9 of Spielpassung; Said cylinder body boss radially has 5 left suction chambers, 5 left sides extrude chamber, 5 right suction chambers, 5 right chambeies that extrude, and 5 left suction chambers, 5 left sides extrude chamber, 5 right suction chambers and 5 right coaxial one by one correspondences in chamber that extrude; 5 left suction chamber positions are corresponding with 5 plunger cavity positions of cylinder body boss left side respectively, and are communicated with plunger cavity and inlet port; 5 left sides extrude the chamber and are communicated with oil drain out through second duct 26 respectively; 5 right suction chambers are communicated with inlet port through the 3rd duct 27 respectively; 5 right chambeies that extrude are communicated with plunger cavity and oil drain out respectively; Be equipped with respectively in 5 left suction chambers and 5 the right suction chambers that 12,5 left sides of suction valve assembly extrude chambeies and 5 right extrusion in the chambeies are equipped with delivery valve assembly 13 respectively;

Left end cap 2 inboard with right end cap 17 inboards respectively with left swash plate 7, that right swash plate 24 passes through locating stud 6 is fastening, said left swash plate 7 is coaxial with the center of right swash plate 24, card is parallel;

Hold mutually through the strut 14 in said first duct 25 between the plunger piston slippery boots assembly 9 of per two the coaxial correspondences of the left and right end face of said cylinder body boss; It is right to constitute plunger-piston shoes, and each plunger-piston shoes is pressed on the card of left swash plate 7 and right swash plate 24 respectively to two ends piston shoes head;

Said cylinder body 11 right-hand members stretch out right end cap 17, adopt the oil drain out of screw plug 21 closed cylinders 11 right sides, and cylinder body 11 right-hand member sides have the radially oil drainage hole of the said oil drain out of UNICOM,

Right bearing lid 19 is fastened on right end cap 17 outer side center through screw 3; Tapered roller bearing 5 is held in cylinder body 11 right-hand members; Said right bearing lid 19 is the cylindrical shape of bottom lock, and the inside is equipped with end cover 22, is limited the Cock screw 20 that passes right bearing lid 19 to rotate in a circumferential direction; End cover 22 is the inwardly protruded cylinder of last lower limb; Bore cooperates with said cylinder body 11 right-hand member external diameters about it, is placed in said cylinder body 11 right-hand members, and end cover 22 1 ends are by circlip 23 axial limitings that are embedded in the right bearing lid 19; Said right bearing lid 19 has oil outlet with the radially oil drainage hole position of corresponding said cylinder body 11 right-hand member sides, end cover 22 sides; Hydraulic oil is communicated with the hydraulic system in the external world from cylinder body 11 side oil drainage holes through holding the cover 22 and the oil outlet of right bearing lid 19.

Shown in Fig. 2 (A), Fig. 2 (B), said left suction chamber, right suction chamber shape are identical, are the secondary shoulder hole, and the following hole UNICOM less by the bigger last hole of internal diameter and internal diameter constitutes; Said suction valve assembly 12 is made up of spool 28, spring 29, valve seat 30 and bonnet 31, and spool 28, spring 29, valve seat 30 and bonnet 31 are inserted in the last hole of left suction chamber or right suction chamber in regular turn, and spool 28 is spherical; Be pressed in the place, following hole of left suction chamber or right suction chamber, form valve port, said spring 29 1 ends withstand spool 28; Spring 29 the other ends withstand valve seat 30, and valve seat 30 is a ring, has the stepped shaft endoporus; Valve seat 30 tops are withstood by bonnet 31; Said bonnet 31 has the undercut shape cross section, after bonnet 31 is inserted the last hole of left suction chamber or right suction chamber, abdicates the position in first duct 25; The following hole of 5 right suction chambers is communicated with inlet port through 5 the 3rd ducts 27;

Shown in Fig. 3 (A), Fig. 3 (B), a said left side extrudes the chamber, right extrusion cavity shape is identical, is three grades of shoulder holes, and hole, the upper, middle and lower UNICOM of being successively decreased successively by internal diameter constitutes; Said delivery valve assembly is made up of spring 29, spool 28 and valve gap 32, and said spring 29 is inserted a left side and extruded in the mesopore in chamber or right extrusion chamber, and an end is by the hole is spacing down; Said spool 28 is inserted a left side in regular turn with valve gap 32 and is extruded chamber or the right last hole that extrudes the chamber; Spool 28 pressing springs 29 the other ends, spool 28 tops are withstood by valve gap 32, and said valve gap 32 has the undercut shape cross section; After valve gap 32 is inserted the last hole in extrusion chamber, a left side or right extrusion chamber, abdicate the position in first duct 25; The following hole in extrusion chamber, 5 left sides is communicated with oil drain out through 5 second ducts 26;

As shown in Figure 4, said second duct 26 and the 3rd duct 27 are the inclination duct, and they are in cylinder interior even distribution alternate with each other, and isolated mutually between second duct 26 and the 3rd duct 27.

Second duct 26 and the 3rd duct 27 manufacturing process can adopt the method for casting, also can split processing weld in assembling then.

Said cylinder body 11 middle part projection sections and rotor 15 mode that is connected is: said cylinder body 11 middle part boss left hand edges have the seam step; The left side of rotor 15 is withstood spacing by said seam step, the right side of the right side of rotor 15 and cylinder body 11 boss is through flat key, sunk screw and 18 fastening connections of thrust button.

Said cylinder body 11 middle part projection sections and rotor 15 be connected mode can also for:

The left and right sides end face of the left and right sides end face of rotor 15 and cylinder body 11 boss is respectively through flat key, sunk screw and 18 fastening connections of thrust button.

Claims

1. plunger type electric-motor pump; Comprise shell (8), motor stator (16), rotor (15), cylinder body (11), a 2N plunger piston slippery boots assembly (9), left swash plate (7), right swash plate (24) and 2N suction valve assembly (12) and 2N delivery valve assembly (13); N is 3～11 odd number; Said shell (8), motor stator (16) and rotor (15) are cylindrical shape; Motor stator (16) is assemblied in the shell (8), and left end cap (2) and right end cap (17) are fixed in said shell (8) right ends through bolt (1) respectively, and said cylinder body (11) is for having the step axle of middle part boss; Its two ends are supported on left end cap (2) center and right end cap (17) center by tapered roller bearing (5) respectively; Left bearing lid (4) is fastened on left end cap (2) center through screw (3), and the tapered roller bearing (5) of left end is held out against in cylinder body (11) left end, and left bearing covers (4) center and has oil through; Cylinder body (11) middle part projection section is with rotor (15) and is connected; It is inner and have air gap between the two that rotor (15) is positioned at motor stator (16), and cylinder body (11), rotor (15), motor stator (16) three are coaxial, and the cylinder body longitudinal center line is as the central rotating shaft of rotor (15);

The left and right two ends of said cylinder body (11) have axial inlet port and oil drain out; The left and right end face axial of cylinder body boss has the plunger cavity along the equally distributed N of circumference; The coaxial one by one correspondence of N plunger cavity of the left and right end face of cylinder body boss, and through first duct (25) connection; Be inlaid with plunger bushing (10) in each plunger cavity, plunger bushing (10) is built-in with the plunger piston slippery boots assembly (9) of Spielpassung; Said cylinder body boss radially has N left suction chamber, a N left side extrudes chamber, a N right suction chamber, a N right chamber that extrudes, and N left suction chamber, a N left side extrude chamber, a N right suction chamber and N the right coaxial one by one correspondence in chamber that extrudes; N left suction chamber position is corresponding with N plunger cavity position of cylinder body boss left side respectively, and is communicated with plunger cavity and inlet port; A N left side extrudes the chamber and is communicated with oil drain out through second duct (26) respectively; N right suction chamber is communicated with inlet port through the 3rd duct (27) respectively; N the right chamber that extrudes is communicated with plunger cavity and oil drain out respectively; In N left suction chamber and N right suction chamber suction valve assembly (12) is housed respectively, extrusion chamber, a N left side and N right the extrusion in the chamber are equipped with delivery valve assembly (13) respectively; It is characterized in that:

Left end cap (2) inboard with right end cap (17) inboard respectively with left swash plate (7), that right swash plate (24) passes through locating stud (6) is fastening, said left swash plate (7) is coaxial with the center of right swash plate (24), card is parallel;

Hold mutually through the strut (14) in said first duct (25) between the plunger piston slippery boots assembly (9) of per two the coaxial correspondences of the left and right end face of said cylinder body boss; It is right to constitute plunger-piston shoes, and each plunger-piston shoes is pressed on the card of left swash plate (7) and right swash plate (24) respectively to two ends piston shoes head;

Said cylinder body (11) right-hand member stretches out right end cap (17), adopts the oil drain out of screw plug (21) closed cylinder (11) right side, and cylinder body (11) right-hand member side has the radially oil drainage hole of the said oil drain out of UNICOM,

Right bearing lid (19) is fastened on right end cap (17) outer side center through screw (3); Tapered roller bearing (5) is held in cylinder body (11) right-hand member; Said right bearing lid (19) is the cylindrical shape of bottom lock, and the inside is equipped with end cover (22), is limited the Cock screw (20) that passes right bearing lid (19) to rotate in a circumferential direction; End cover (22) is the inwardly protruded cylinder of last lower limb; Bore cooperates with said cylinder body (11) right-hand member external diameter about it, is placed in said cylinder body (11) right-hand member, and end cover (22) one ends are by circlip (23) axial limiting that is embedded in the right bearing lid (19); The radially oil drainage hole position of said right bearing lid (19) and corresponding said cylinder body (11) right-hand member side, end cover (22) side has oil outlet; Oil drainage hole is communicated with extraneous hydraulic system through the oil outlet that end cover (22) and right bearing cover (19) to hydraulic oil from cylinder body (11) side.

2. plunger type electric-motor pump as claimed in claim 1 is characterized in that:

Said left suction chamber, right suction chamber shape are identical, are the secondary shoulder hole, and the following hole UNICOM less by the bigger last hole of internal diameter and internal diameter constitutes; Said suction valve assembly (12) is made up of spool (28), spring (29), valve seat (30) and bonnet (31), and spool (28), spring (29), valve seat (30) and bonnet (31) are inserted in the last hole of left suction chamber or right suction chamber in regular turn, and spool (28) is spherical; Be pressed in the place, following hole of left suction chamber or right suction chamber; Form valve port, said spring (29) one ends withstand spool (28), and spring (29) the other end withstands valve seat (30); Valve seat (30) is a ring; Have the stepped shaft endoporus, valve seat (30) top is withstood by bonnet (31), and said bonnet (31) has the undercut shape cross section; After bonnet (31) is inserted the last hole of left suction chamber or right suction chamber, abdicate the position of first duct (25); The following hole of N right suction chamber is communicated with inlet port through N the 3rd duct (27);

A said left side extrudes the chamber, right extrusion cavity shape is identical, is three grades of shoulder holes, and hole, the upper, middle and lower UNICOM of being successively decreased successively by internal diameter constitutes; Said delivery valve assembly is made up of spring (29), spool (28) and valve gap (32); Said spring (29) is inserted a left side and is extruded in the mesopore in chamber or right extrusion chamber; One end is by the hole is spacing down, and said spool (28) and valve gap (32) are inserted a left side in regular turn and extruded chamber or the right last hole that extrudes the chamber, spool (28) pressing spring (29) the other end; Spool (28) top is withstood by valve gap (32); Said valve gap (32) has the undercut shape cross section, after valve gap (32) is inserted the last hole in extrusion chamber, a left side or right extrusion chamber, abdicates the position of first duct (25); The following hole in extrusion chamber, a N left side is communicated with oil drain out through N second duct (26);

Said second duct (26) and the 3rd duct (27) are the inclination duct, and they are in cylinder interior even distribution alternate with each other, and isolated mutually between second duct (26) and the 3rd duct (27).

3. according to claim 1 or claim 2 plunger type electric-motor pump is characterized in that:

Said cylinder body (11) middle part projection section and rotor (15) mode of being connected are: said cylinder body (11) middle part boss left hand edge has the seam step; The left side of rotor (15) is withstood spacing by said seam step, the right side of the right side of rotor (15) and cylinder body (11) boss is through fastening connection of flat key, sunk screw and thrust button (18).

4. according to claim 1 or claim 2 plunger type electric-motor pump is characterized in that:

Said cylinder body (11) middle part projection section with rotor (15) mode of being connected is: the left and right sides end face of the left and right sides end face of rotor (15) and cylinder body (11) boss is respectively through fastening connection of flat key, sunk screw and thrust button (18).