RU1788312C - Piston motor - Google Patents

Abstract

Usage: in mechanical engineering, namely, in volumetric hydraulic machines. The inventive motor contains a housing 7, a front end cover 4, a rear end cover G with channels for supplying and discharging fluid and cylinder blocks 9 with pistons located in the housing 7, mounted on a hollow eccentric output shaft 1, and furthermore contains an insert 12 in the form cylindrical ring. with a flat annular protrusion, spring 17, bushings 16 with annular outer and inner recesses, support discs 13 and couplings 14 with radial inlet and axial drainage holes, the back cover 5 is made of two x parts, the spring 17 is located in the inner recesses of the sleeves 16, installed between the couplings 14, the insert 12 is mated with the outer recesses of the sleeves 16 with its cylindrical section, and is fixed between the parts of the back cover 5 flat, the inner diameter of the cylindrical surface of the insert 12 is less than the diameter of the outer sleeve dimension 16. 1 z.p. f-ly, 3 ill. (L C

Description

The invention relates to techniques related to the manufacture and operation of volumetric hydraulic machines.

A piston motor converts hydraulic energy into mechanical energy and can fulfill its functions in the power drive of rolling equipment, winches, transmissions of mobile machines, in the mechanisms of robots and manipulators, and also as a power drive of metalworking machines.

The described analogues cannot fulfill the function of, for example, turning, drilling and milling machines, since they do not satisfy a number of requirements, the main of which are:

- the presence of a through hole in the shaft with the possibility of fixing the faceplate on it;

- combination of qualities of high-torque and low-torque motors;

- relatively high static and dynamic balance;

- high reliability, durability, compactness.

Analogs in the form of axial hydraulic machines are not suitable for the above purposes due to the lack of designs with a hollow shaft and insufficient static and dynamic imbalance of the rotor and piston group.

A radial-piston hydraulic motor with a hollow shaft is also not suitable, since it does not combine the qualities of high-torque and high-speed hydraulic motors and does not provide a speed of 4000.

As a prototype, a radial piston motor was selected, the shaft of which can be made monolithic or hollow.

In the prototype and in the inventive reciprocating motor, the same fluid distribution system that feeds and discharges fluid from a rotating shaft through a fixed housing cover. Fluid through the shaft channels is supplied to one of the two distribution grooves of each cam. These grooves connect the cylinder chambers for half a turn to the pressure head and for the other half of the turn to the drain line. The rotating shaft may have a runout with respect to the fixed housing cover, and therefore requires the use of special sealing means in the fluid transition unit from the housing cover to the shaft.

The disadvantage of the prototype is the low reliability of the sealing means in said assembly.

The goal is to improve the tightness of the fluid inlet and outlet. To achieve this goal, the motor is equipped with an insert in the form of a cylindrical ring with a flat annular protrusion, a spring, bushings with ring outer and inner recesses, support discs, couplings with radial inlet and axial drainage holes, while the back cover is made of two parts , the spring is located in the inner recesses of the bushings installed between the couplings and spring-loaded to them, and the insert, with its cylindrical section, is mated to the external recesses of the bushings and flat fixed between ast mi back cover.

The inner diameter of the cylindrical surface of the insert is less than the diameter of the outer dimension of the bushings.

In the design of the application is achieved:

- combining the action of one spring on two sets of parts;

- interchangeability of parts in the inlet and outlet lines;

- maintaining the simplicity of the shaft device.

A significant difference is that the insert, bushings and couplings, interconnected, provide a regulated ratio of hydrostatic compressive and compressive forces during reverse flow.

Figure 1 presents a longitudinal section of the motor and its node supply and removal of fluid; figure 2 is a cross section with elements of a node for supplying and discharging liquid; Fig. 3 shows a design diagram of a fluid inlet (or outlet) assembly.

The hydraulic motor (Fig. 1) has a hollow shaft 1 in which the tubular part 2 is rigidly mounted. The longitudinal grooves of the material on the outer surface of this part are disconnected from each other and form cavities for supplying and discharging liquid from the cylinder chambers through eccentrics. The hollow shaft is mounted on bearings 3 in the front 4 and in the rear cover 5. The rear cover is divided into two parts 5 and 6 and attached to the housing 7. On the hollow shaft 1, the eccentrics 8 are rigidly fixed, with the mutual rotation of the pair of extremes relative to the middle pair by 180 ° .. The outer surface of the eccentrics acts as a distributor and this surface is associated with the inner surface of the cylinder blocks 9. The number of cylinder blocks is four. Plungers 10 are installed in the cylinder bores, which during operation interact with the fixed support plate 11.

The fluid inlet and outlet assembly consists of two parts 5 and 6 of the back cover, an insert 12 in the form of a cylindrical ring with an annular protrusion, two sets of sealing parts. Leaks accumulate in the body cavity and are discharged through the opening C. The two extreme support discs 13 are in contact with the corresponding ends of the couplings 14. The couplings 14 have radial inlet (or outlet) openings. The second end of the clutch 14 is in contact with the ends of the bushings 16. The bushings 16 have inner and outer annular grooves. The inner recesses are designed to accommodate the spring 17, and the outer ones for tight connection with the corresponding surface of the annular protrusion of the insert 12. The bushings 16 are axially susceptible to the action of the spring, and when the motor is operating under the action of the working pressure, they are pressed against the ends of the couplings 14.

Figure 2 shows a cross section of the motor in section aa; Bb. A section of the sleeve 14 (Fig. 2) shows a series of radial drills O for the flow of the working fluid and axial channels K for the through connection of the stub cavities with the drain line. A pair of locking screws 15 is installed between the holes of the coupling 14. These screws hold the coupling 14 on the shaft from relative rotation. The locking screws 15 do not exclude some axial displacement of the coupling 14 when it is worn, the slotted groove Щ1 on the shaft is oriented relative to the jumpers (11 on the tubular part 2, the M2 line is hermetically disconnected from the M1 line.

In Fig. 3, a design diagram of the fluid supply (or tap) assembly is given. The diagram gives an idea of pressure plots on the sealing (sealing) ends of bushings, couplings, and support discs. An approximately linear law of pressure drop is observed in the thin layer of the end gap. The area of the sealing grooves on both ends of the coupling is the same, therefore, the hydrostatic pressing forces are the same, which we denote Т0тж Working pressure in one of the lines (for example M2) propagates through the radial holes in the coupling to the cylinder blocks and the same pressure propagates through the radial clearance couplings and sleeves 16 in the annular volume behind the shoulder of this sleeve.

On the area l (R22 - Ri2), a pressing force Tmr appears, which coincides in direction with the action of the spring.

According to the regulated ratio of pressing and pressing forces

ATriz-Toj

A is the ratio of forces is known from the handbooks. The force of the compression spring is neglected. With this in mind, a simplified calculation

A (R22-Ri2) 0.5 (R2-Ro2) Description in working condition.

Of the two lines M1 and M2, one is pressure and the other is a drain. Suppose pressure is applied to line M2. The liquid under these pressures freely penetrates through the sleeve 14 to the cylinder chambers. The clutch is sealed on the shaft and rotates with the shaft. The end surfaces of the clutch 14 interact with the corresponding planes of the support discs 13 and the bushings 16, which do not rotate.

The regulated ratio of forces pressing the collar of the sleeve 16 to the clutch and squeezing this collar from the end surface of the clutch ensures minimal friction and reliable sealing.

Further, the flow through the slot Щ2 enters the cavity formed by the inner surface of the shaft and the surface of the tubular insert 2 to the grooves on the eccentrics 8.

According to the figure in figure 1, the neutral plane is located in the plane of the sheet. Eccentrics 8 are rotated 180 ° in pairs. Two longitudinal jumpers on the tubular insert 2 separate the recesses forming the fluid inlet and outlet cavities. They are

oriented relative to the neutral plane. The liquid under working pressure is supplied to a pair of extreme eccentrics, for example, facing our gaze, i.e. on one side of the neutral plane and to

a pair of averages located on the other side of the neutral plane. The eccentricity of the pair of extreme blocks (Fig. 1) is lower than the main axis, and the pairs of middle ones are above the axis. Porshnev resultant pair strength

extreme blocks is directed from our gaze, and similar forces of a pair of middle blocks are directed to our gaze. The moment from all 4 blocks is summed on the shaft. The neutral plane rotates with the shaft. Blocks have

scanning motion. Pistons entering the discharge phase displace the fluid through the channels and windows to the fluid return line.

In assessing the technical and economic efficiency of the proposed unit for supplying and discharging liquids, the following should be taken into account:

increase the reliability and durability of the motor;

ensuring high tightness with minimal friction.

Claims (2)

SUMMARY OF THE INVENTION 1. A piston motor comprising a housing, a front end cover, a rear end cover with fluid inlet and outlet channels, and piston cylinders located in the housing mounted on a hollow eccentric output shaft, characterized in that, in order to improve the tightness of the assembly fluid inlet and outlet to the rotating shaft, the motor is equipped with an insert in the form of a cylindrical ring with a flat annular protrusion, a spring, bushings with annular external and internal grooves, support discs and couplings with radial inlet and axial drainage holes, the back cover being made of two parts, the spring is located in the inner grooves of the bushings installed between the couplings and spring-loaded to them, and the insert has its own cylindrical section wife with outdoor recessed bushings, and flat - fixed between parts of the back cover. 2. The motor according to claim 1. Characterized in that the inner diameter of the cylindrical surface of the insert is smaller. Diameter outer dimension of bushings. AA; H-5 % g2 Fig.Z