CN1542295A - Fully water-lubricated pure water hydraulic axial piston pump/motor - Google Patents

Abstract

The invention discloses a fully water-lubricated pure water hydraulic axial piston pump/motor, which uses filtered natural water (including fresh water and sea water) as the working medium, and is mainly composed of a shell and a rotatable pump installed in the shell. composition of the cylinder. There are an odd number of cylinder holes parallel to the drive/output shaft evenly distributed on the same circumference of the cylinder body. The plunger in the plunger shoe assembly is placed in the cylinder hole, and a flow sleeve is installed on the other end of the cylinder hole. Put it into the corresponding hole on the thrust plate, the thrust plate floats relative to the cylinder body, automatically compensates the error of parts processing and installation, one end of the center spring presses the thrust plate on the distribution plate through the compression plastic rod, and the other end The sliding shoe is pressed on the swash plate through the cylinder body, spherical joint and return plate, and the drive/output shaft and the cylinder body are connected by interference fit. All the friction pairs of the device of the present invention are directly lubricated and cooled with water, and have small radial dimension, small volume, light weight and high specific power.

Description

Fully water-lubricated pure water hydraulic axial piston pump/motor

Technical field

The invention relates to an energy conversion device in hydraulic transmission, in particular to a fully water-lubricated pure water hydraulic axial plunger pump/motor.

Background technique

Pure water hydraulic transmission technology uses filtered natural water (including seawater and fresh water) as the hydraulic medium, which has the advantages of cleanness, no pollution, and no fire hazard. In the past ten years, the development of new materials, the progress of processing technology and the successful development of hydraulic components with new structures have overcome the shortcomings of early hydraulic transmissions such as easy corrosion, easy wear, large leakage, and low efficiency, making pure water hydraulic transmission The technology has made great progress, and it has begun to widely enter the industrial application fields such as food, paper making, textile, medical equipment, fire protection, metallurgy, mining, nuclear power plant, and ocean development.

The pure water hydraulic pump/motor is the key power component in the pure water hydraulic system, and its performance index directly determines the performance index of the entire pure water hydraulic system. So far, the pure water hydraulic pumps/motors that have been developed mainly have the following two representative structures:

The first is oil-water separation, valve distribution axial plunger structure. This structure adopts cone valve flow distribution, the plunger and the cylinder hole are axially distributed on the circumference relative to the main shaft, and the reciprocating motion of the plunger is realized by the swash plate and the central spring. The distribution valve and cylinder bore are submerged in water, and other major friction pairs (such as plunger ball head and slider ball socket, slider sole and swash plate, bearings, etc.) are submerged in oil. In order to prevent the oil and water from colluding, a seal must be added on the friction pair of the plunger and the cylinder bore to isolate the oil and water. The overall device life depends on the life of the seal ring. This structure is a transitional technology proposed in the initial stage of the development of pure water hydraulic technology to solve the problem of shortage of water-lubricated friction pair materials.

The second is full water lubrication, valve distribution radial plunger structure. The representative is the German Hauhinco company. This structure uses a flat valve for flow distribution, and the plunger and cylinder hole are distributed radially and uniformly relative to the circumference of the main shaft. The reciprocating motion of the plunger is realized by the eccentric wheel on the main shaft and the return spring at the root of each plunger. All friction pairs are directly lubricated and cooled with water. This structure has a large radial dimension, and the entire device has a large volume and low specific power.

Contents of the invention

The purpose of the present invention is to provide a pure water hydraulic axial piston pump/motor with full water lubrication, which utilizes filtered natural water (including fresh water and sea water) as the pressure working medium and lubricating medium, and does not need any other lubricant.

In order to achieve the above object, the technical solution adopted by the present invention is that it includes: a shell composed of a left end cover, a right end cover, and a housing, the cylinder bearing hole in the shell is equipped with a cylinder, and the cylinder is evenly distributed on the same circumference as the cylinder. There are an odd number of cylinder holes parallel to the body axis. The plunger in the plunger shoe assembly is placed in the cylinder hole and forms a plunger pair with the plunger. A thrust plate is installed at one end of the cylinder body, and a spring placed in the center hole of the cylinder body One end of the thrust plate is pressed against the distribution plate by pressing the plastic rod. The thrust plate and the distribution plate form a friction pair—a distribution pair. The other end of the central spring passes through the cylinder body, the ball joint outside the cylinder, and the return stroke outside the ball joint The sliding shoe in each plunger sliding shoe assembly is pressed against the swash plate, and one end of the drive/output shaft passes through the sliding bearing in the center of the left end cover and is inserted into the center of the cylinder to form an interference fit with the cylinder. One end is correspondingly put into a cylinder hole, and the other end of the flow distribution sleeve is put into the corresponding hole on the thrust plate. The distribution plate is fixed on the right end cover, and the other two positioning pins fix the swash plate on the left end cover, and there are water guide grooves in the sliding bearing and the cylinder bearing.

The plunger of the plunger slipper assembly is placed in the cylinder bore, and the inner wall of the cylinder bore is injected with an engineering plastic layer and a metal plunger to form a plunger pair.

There are 7 or 9 odd-numbered cylinder holes parallel to the axis of the cylinder body evenly distributed on the same circumference of the cylinder body.

The said shoe includes: a semicircular base body made of metal material, which is covered with an engineering plastic layer in the ball socket of the base body, outside the cylindrical surface of the base body, and on the side of the base body, and the ball socket covered with the engineering plastic layer is formed by the ball head of the plunger. In the ball and socket pair, the cylindrical surface of the base body covered with the engineering plastic layer is loaded into the hole of the return plate, and the side surface covered with the engineering plastic layer and the swash plate form a sliding shoe pair.

The beneficial effects that the present invention has are:

The device adopts flow distribution on the end face of the distribution plate, and the reciprocating motion of the plunger is realized by the swash plate and the central spring; all friction pairs are directly lubricated and cooled by water, with small radial size, small volume, light weight and high specific power.

The drive/output shaft and the cylinder block are interference fit. In this way, the concentricity between the cylinder body and the drive/output shaft is high, and the cylinder body runs smoothly. The length of the drive/output shaft is short and the deformation of the shaft is small. The axial size of the pump/motor is small, and the whole device has a compact structure.

There is a certain radial clearance between the distribution sleeve and the cylinder bore and the thrust plate, so that the thrust plate can float relative to the cylinder body. The floating end face distribution can automatically compensate the errors of parts processing and installation. There are O-ring rubber seals at both ends of the distribution sleeve. Make sure that high-pressure water does not leak from the radial clearance of the distribution sleeve.

The left sliding bearing is installed in the left end cover to support the drive/output shaft; the cylinder bearing is installed in the housing to support the cylinder. In this way, the drive/output shaft is basically not affected by the bending moment, but only bears the torque, thereby reducing the wear of the shaft and prolonging the service life of the shaft.

The matching materials of the main friction pairs are stainless metal materials and engineering plastics, which not only ensure the corrosion resistance, strength, toughness and rigidity of the components in the pure water hydraulic axial piston pump/motor, but also ensure the self-sufficiency of each friction pair. Lubricating, wear-resistant, shock-absorbing and other tribological properties can effectively avoid the phenomenon of adhesive wear, corrosion wear and jamming of the friction pair under the condition of high speed, heavy load and water lubrication, and effectively improve the working reliability and service life. life.

Description of drawings

Fig. 1 is the structural principle schematic diagram of the present invention;

Figure 2 is an enlarged view of the plunger shoe assembly.

In the figure: 1 key, 2 drive/output shaft, 3 baffle plate, 4 shaft seal, 5 sliding bearing, 6 left end cover, 7 housing, 8 swash plate, 9 sliding shoe, 10 plunger, 11 center spring, 12 O Shaped rubber sealing ring, 13 distribution sleeve, 14 thrust plate, 15 distribution plate, 16 right end cover, 17 distribution plate pillar, 18 positioning pin, 19 compression plastic rod, 20 cylinder block, 21 cylinder block bearing, 22 spherical hinge, 23 return trip disk.

Detailed ways

As shown in Fig. 1 and Fig. 2, the present invention comprises a shell (comprising left end cover 6, right end cover 16, housing 7) and a rotatable cylinder body 20 installed in the shell. Cylinder holes parallel to the axis of the cylinder body 20 are evenly distributed on the same circumference of the cylinder body 20. The plunger 10 of the plunger shoe assembly is placed in the cylinder hole, and the inner wall of the cylinder hole is injected with engineering plastics and the plunger 10 of stainless metal material. Dubbed as a plunger pair. On the right side of the cylinder block 20 is the thrust plate 14 . The central spring 11 placed in the center of the cylinder body 20 compresses the sliding shoe 9 and the swash plate 8 of each plunger shoe assembly through the cylinder body, the ball joint 22 and the return plate 23 . The other end of the central spring 11 presses the thrust plate 14 to the flow plate 15 by pressing the plastic rod 19 . The thrust plate 14 and the distribution plate 15 form a pair of friction pairs—a distribution pair. The distribution sleeve 13 connects the cylinder body 20 and the thrust plate 14 and makes the thrust plate 14 rotate together with the cylinder body 20 . One end of the distribution sleeve 13 is packed into the cylinder bore, and the other end is packed into the corresponding hole on the thrust plate 14 . There is a certain radial clearance between the flow distribution sleeve 13 , the cylinder hole 20 and the thrust plate 14 , so that the thrust plate 14 can float relative to the cylinder body 20 . There are O-shaped rubber sealing rings 12 at both ends of the distribution sleeve 13 to ensure that high-pressure water does not leak from the radial gap of the distribution sleeve. The distribution pillar 17 and the positioning pin 18 fix the distribution plate 15 on the right end cover 16 . One end of the drive/output shaft 2 passes through the sliding bearing 5 at the center of the left end cover 6, and the shaft end has a keyway for installing the key 1; Two positioning pins 18 fix the swash plate 8 on the left end cover 6 . Axle 2 is supported by sliding bearing 5, and cylinder block 20 is supported by cylinder block bearing 21. There are several water guide grooves in sliding bearing 5 and cylinder block bearing 21, and water is introduced to play a role in lubrication and cooling. The water guiding groove of the cylinder block bearing 21 also communicates with the water chambers on the left and right sides. The shaft end seal is completed by the skeleton type shaft seal 4, and the outside of the skeleton type shaft seal 4 is the baffle plate 3.

When the device of the present invention is used as a pump, the water pumping process is as follows: the drive shaft 2 drives the cylinder body 20, the thrust plate 14, the plunger shoe assembly rotates, the central spring 11 passes through the cylinder body 20, the ball joint 22 and the return disk 23 The active force is evenly applied to each sliding shoe 9 to ensure that the sole of the sliding shoe 9 always slides closely against the slope of the swash plate 8, thereby realizing the continuous reciprocating motion of the plunger 10 in the cylinder bore. When the plunger 10 moves to the left limit position to the left, the corresponding waist-shaped window on the thrust plate 14 is fully covered by the flow plate 15, and the cylinder bore is closed. With the rotation of the drive shaft 2, the sliding shoe 9 slides against the swash plate 8 under the action of the spring force, driving the plunger 10 to move to the right, reducing the closed volume of the cylinder hole, increasing the water pressure, and then thrusting The waist-shaped window of disc 14 communicates with the high-pressure waist-shaped window of distribution plate 15, and the high-pressure water in the cylinder hole is continuously discharged by plunger 10, and reaches the outlet of the pump through the high-pressure waist-shaped window of distribution plate 15, realizing the drainage process of the pump . When the plunger 10 moves to its right limit position, the volume of the cylinder bore can no longer be increased. At this time, the corresponding waist-shaped window on the thrust plate 14 is also completely covered by the valve plate 15, and the cylinder bore is closed again. As the drive shaft 2 continues to rotate, the closed volume of the cylinder bore increases, and the water pressure decreases, then the waist window of the thrust plate 14 communicates with the low-pressure waist window of the distribution plate 15, and the low-pressure water continuously enters the cylinder from the inlet of the pump through the distribution plate 15 In the hole, the water absorption process of the pump is completed. With the rotation of the drive shaft 2, each cylinder hole will continue to absorb and drain water, and multiple plungers 10 complete the suction and drain work independently in a certain order, and the high-pressure water discharged by each plunger 10 is discharged at the outlet of the pump. Orderly superposition, so as to pump out high-pressure water with continuous and uniform flow.

When the device is used as a motor, the working process is the reverse process of the pump working process.

All friction pairs of this device are directly lubricated and cooled by water, including cylinder bore and plunger, plunger ball head and shoe ball socket, shoe sole and swash plate, thrust plate and flow plate, drive/output shaft and left Sliding bearings, cylinder and cylinder bearings, ball joints and return discs, etc. Specifically, this is achieved:

There is a certain gap between the cylinder hole and the plunger 10, and the sealing is realized by this gap. During the drainage process, there is high-pressure water in the cylinder hole, and a high-low pressure difference is formed at both ends of the sealing gap between the cylinder hole and the plunger 10, so that the high-pressure water in the cylinder hole leaks into the low-pressure housing through the sealing gap. The pressure of this part of the leakage water in the gap decreases successively, and has a considerable bearing capacity. For the friction pair of the cylinder hole and the plunger 10, it plays a supporting, lubricating and cooling role.

The high-pressure water in the cylinder hole also passes through the center hole of the plunger, and the center hole of the plunger ball head reaches the friction pair of the plunger ball head and the ball socket of the sliding shoe for lubrication; The disc friction pair forms a static pressure bearing.

There are many water guide grooves in the left sliding bearing 5 and the cylinder bearing 21, and the water in the housing is introduced therein to lubricate and cool the two pairs of bearing pairs.

The main friction pairs of this device are all made of stainless metal materials and engineering plastics. This pairing has the characteristics of corrosion resistance, wear resistance and self-lubrication, which can effectively ensure sufficient reliability and service life under water lubrication conditions. Details are as follows:

Bearing pair has two: slide bearing 5 and drive/output shaft 2, cylinder block bearing 21 and cylinder block 20, two slide bearings all adopt engineering plastics to make completely, and axle 2 and cylinder block 20 are stainless metal materials. The ball joint pair is a ball joint 22 and a return plate 23, wherein the ball joint 22 is made of stainless metal material, and the return plate 23 consists of two parts, the first part is the base body of the stainless metal material, and the second part is an injection molding project A plastic ball socket, which cooperates with the ball joint 22 to form a ball joint pair. Cylinder block 20 also comprises two parts, and the first part is the base body of stainless metal material, and the second part is the engineering plastics injected in the cylinder hole of cylinder block base body, and it forms plunger pair with the plunger of stainless metal material. Sliding shoe 9 is also divided into two parts, the first part is stainless metal material substrate 9.1, and the second part is engineering plastics 9.2 injection molded at its ball socket and the end face contacted with the swash plate, and it forms a ball with the ball head of plunger 10. The nest pair forms the shoe pair with the slope of the swash plate 8. In the middle of the flow distribution plate 15 is a metal substrate, which is injection-molded engineering plastics on both sides, and forms a flow distribution pair with the thrust plate 14 of stainless metal material.

In a word, the main friction pair matching materials used in the device of the present invention are stainless metal materials and engineering plastics, which not only ensure the corrosion resistance, strength, toughness and rigidity of the parts in the pure water hydraulic axial pump/motor, but also ensure the The self-lubricating, wear-resistant, shock-absorbing and other tribological properties of each friction pair can effectively avoid the phenomenon of adhesive wear, corrosion wear and seizure of the friction pair under the condition of high speed, heavy load and water lubrication, and effectively improve the Work reliability and service life.

Claims (4)

1, a kind of pure water hydraulics axial plunger pump/motor of fully water lubricating, it is characterized in that it comprises: by left end cap (6), right end cap (16), the shell that housing (7) is formed, cylinder body bearing (21) endoporus in the shell is equipped with cylinder body (20), be evenly equipped with odd number cylinder hole on the same circumference of cylinder body (20) with cylinder body (20) parallel axes, plunger in the plunger piston slippery boots assembly (10) places in the cylinder hole, constitute trunk piston set with plunger (10), cylinder body (20) one ends are equipped with thrust button (14), place an end of the spring (11) of cylinder body (20) center hole thrust button (14) to be pressed on the thrust plate (15) through compressing plastic rod (19), thrust button (14) and thrust plate (15) constitute friction pair-flow pair, central spring (11) the other end is by cylinder body (20), the ball pivot (22) that cylinder body is outer, the outer backhaul dish (23) of ball pivot is pressed in the piston shoes in each plunger piston slippery boots assembly (9) on the swash plate (8), the sliding bearing (5) that one end of driving/output shaft (2) passes left end cap (6) center inserts cylinder body (20) center, constitute interference fit with cylinder body (20), each flow cover (13) one end is correspondingly packed in the cylinder hole, the other end of flow cover (13) is packed in the last corresponding hole of thrust button (14), thrust button (14) is unsteady with respect to cylinder body (20), at right end cap (16) center flow pillar (17) is housed, flow pillar (17) and locating stud (18) are fixed on thrust plate (15) on the right end cap (16), two other locating stud (18) is fixed on swash plate (8) on the left end cap (6), all has the water guide groove in sliding bearing (5) and the cylinder body bearing (21).

2, according to the pure water hydraulics axial plunger pump/motor of the described a kind of fully water lubricating of claim 1, it is characterized in that: the plunger of plunger piston slippery boots assembly (10) places in the cylinder hole, and the plunger (10) of cylinder hole inwall injection moulding engineering plastics layer and metal constitutes trunk piston set.

3, according to the pure water hydraulics axial plunger pump/motor of the described a kind of fully water lubricating of claim 1, it is characterized in that: the odd number cylinder hole that is evenly equipped with on the same circumference of cylinder body (20) with cylinder body (20) parallel axes is 7 or 9.

4, according to the pure water hydraulics axial plunger pump/motor of the described a kind of fully water lubricating of claim 1, it is characterized in that said piston shoes (9) comprising: the semicircle matrix (9.1) that metallic material is made, in matrix (9.1) ball-and-socket, outside the matrix cylndrical surface, the matrix side covers engineering plastics layers (9.2), be coated with the ball-and-socket of engineering plastics layer and the bulb of plunger (10) and constitute the ball-and-socket pair, pack in backhaul dish (23) hole in the matrix cylndrical surface that is coated with the engineering plastics layer, the side and the swash plate (8) that are coated with engineering plastics constitute the piston shoes pair.

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