CN116335935A - Axial piston pump one-way control valve and control method - Google Patents

Abstract

The invention discloses a one-way control valve of an axial piston pump and a control method thereof. The one-way control valve comprises a valve sleeve (1), and a slidingly connected valve core (3) is arranged inside the valve sleeve (1). The valve core ( 3) One side is provided with a spring (2) connected to the valve sleeve (1), the other side of the valve core (3) is provided with a plug (5), and the plug (5) is provided with a guide hole ( 50), the guide hole (50) is provided with a ejector rod (4); the side wall of the valve sleeve (1) is provided with a liquid discharge channel (10) and a liquid replenishment channel (11); the valve core (3) is provided with a second One oil passage (30) and the second oil passage (31), one end of the first oil passage (30) and one end of the second oil passage (31) are all connected to the inner cavity of the valve sleeve (1), and the first oil passage ( The other end of 30) is located between the liquid discharge hole (10) and the liquid replenishment hole (11), and the other end of the second oil passage (31) communicates with the liquid replenishment hole (11). The invention has the advantages of fast response speed and low failure rate.

Description

Axial piston pump one-way control valve and control method

technical field

The invention belongs to the field of axial plunger pumps, and in particular relates to a one-way control valve and a control method for axial plunger pumps.

Background technique

Axial piston pump is a kind of positive displacement hydraulic pump. Due to its compact structure, small radial size and small moment of inertia, it is widely used in agricultural machinery, engineering machinery, metallurgy, aviation and other fields.

Axial piston pumps generally have a high-pressure relief check valve. The structure of the existing high-pressure relief check valve is shown in Figure 3. Its function is to limit the peak operating pressure of the plunger pump and form a check valve with other parts. , to realize oil replenishment in the low-pressure chamber of the plunger pump. The existing high-pressure relief check valve is a split structure consisting of a high-pressure relief valve and a check valve. The high-pressure relief valve is used as the spool of the check valve. After being assembled with other parts of the check valve, A high pressure relief check valve is formed. When controlling the charge on and off of the axial piston pump, the high-pressure relief valve, as the spool of the check valve, needs to slide repeatedly in the channel of the check valve. The high-pressure overflow check valve with the above structure is matched with the LHPV-37-L-01C axial piston pump.

However, as shown in Figure 4, since there are multiple oil passages intersecting on the hole wall of the check valve, the high-pressure relief valve is prone to slip and stick due to damage to the hole wall, so that the oil supply circuit cannot be controlled in time. slower. In addition, because the traditional high-pressure relief valve controls the opening and closing of the overflow channel by frequently compressing the spring through the tie rod, the tie rod has the problem of fatigue fracture and a high failure rate.

Therefore, the existing high-pressure relief check valve has the defects of slow response speed and high failure rate.

Contents of the invention

The object of the present invention is to provide a one-way control valve and a control method for an axial piston pump. The invention has the advantages of fast response speed and low failure rate.

The technical scheme of the present invention: the one-way control valve of the axial plunger pump includes a valve sleeve, a valve core that is slidingly connected is arranged in the valve sleeve, a spring connected with the valve sleeve is provided on one side of the valve core, and a spring connected with the valve sleeve is provided on the other side of the valve core. There is a plug on the side, and a guide hole is arranged on the axial direction of the plug, and a ejector rod is arranged in the guide hole;

The side wall of the valve sleeve is provided with a liquid discharge hole and a liquid replenishment hole;

The spool is provided with a first oil passage and a second oil passage, one end of the first oil passage and one end of the second oil passage are connected to the inner cavity of the valve sleeve, and the other end of the first oil passage is located on the side wall of the spool It is located between the liquid discharge hole and the liquid replenishment hole, and the other end of the second oil passage is located on the side wall of the valve core and communicates with the liquid replenishment hole.

In the one-way control valve of the aforementioned axial piston pump, the guide hole includes a middle hole that is slidingly connected with the ejector rod, the end of the middle hole close to the valve core is provided with a bottom hole, and the end of the middle hole far away from the valve core is provided with a top hole , the diameters of the top hole, middle hole, and bottom hole increase sequentially.

In the one-way control valve of the axial piston pump mentioned above, a balance hole is provided on the end surface of the valve core close to the ejector rod, one end of the balance hole is connected to the bottom hole, and the other end of the balance hole is connected to the second oil passage.

In the one-way control valve of the axial piston pump mentioned above, one end of the valve sleeve shrinks inwardly to form a stepped surface, one end of the spring is elastically connected to the valve core, and the other end of the spring is elastically connected to the stepped surface.

In the one-way control valve of the aforementioned axial piston pump, one end of the spool is provided with a blind hole inserted by a spring; the first oil passage includes a first annular groove on the outer peripheral surface of the spool, and the first annular The bottom surface of the groove is provided with a first through hole, and the first through hole communicates with the blind hole; the second oil passage includes a second annular groove on the outer peripheral surface of the valve core, and a second through hole is provided on the bottom surface of the second annular groove. holes, and the second through hole communicates with the bottom surface of the blind hole.

In the aforementioned control method of the one-way control valve of the axial piston pump, the required overflow pressure of the one-way control valve is achieved by presetting the spring stiffness.

Compared with the prior art, the present invention uses the movement of the spool in the valve sleeve to change the oil flow track through structural optimization, and not only has the function of a one-way valve, but also has the function of a high-pressure relief valve, and the structure is simpler , composed of only five parts, the inner hole of the valve sleeve is regular, and there is no cross oil passage, so that the valve core moves smoothly and responds quickly. The improved valve core is a single part, which replaces the existing high-pressure relief valve and has high structural strength. , It is not easy to fatigue and fracture, and the failure rate is significantly reduced. Therefore, the present invention has the advantages of fast response speed and low failure rate.

Description of drawings

Figure 1 is a front view of the present invention.

Fig. 2 is a structural schematic diagram of the spool.

Fig. 3 is a structural schematic diagram of an existing high-pressure relief valve.

Fig. 4 is a structural schematic diagram of a channel of a conventional one-way valve.

The marks in the attached drawings are: 1-valve sleeve, 2-spring, 3-spool, 4-ejector, 5-plug, 10-discharging channel, 11-refilling channel, 12-step surface, 30-the first One oil passage, 31-second oil passage, 32-balance hole, 33-blind hole, 34-first annular groove, 35-first through hole, 36-second annular groove, 37-second through hole, 50 - guide hole, 51 - middle hole, 52 - bottom hole, 53 - top hole.

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings and embodiments, but not as a basis for limiting the present invention.

Example. The one-way control valve of the axial piston pump, as shown in Figure 1, includes a valve sleeve 1, which is provided with a slidingly connected valve core 3, and one side of the valve core 3 is provided with a spring 2 connected to the valve sleeve 1. , the other side of the spool 3 is provided with a threaded plug 5, the plug 5 is provided with a guide hole 50 axially, and the ejector rod 4 is arranged in the guide hole 50;

The side wall of the valve sleeve 1 is provided with a liquid discharge channel 10 and a liquid replenishment channel 11;

The spool 3 is provided with a first oil passage 30 and a second oil passage 31, one end of the first oil passage 30 and one end of the second oil passage 31 are connected to the inner cavity of the valve sleeve 1, and the other end of the first oil passage 30 The other end of the second oil passage 31 is located on the side wall of the valve core 3 and communicates with the replenishment hole 11 .

The guide hole 50 includes a middle hole 51 which is slidingly connected with the ejector rod 4. The end of the middle hole 51 near the valve core 3 is provided with a bottom hole 52, and the end of the middle hole 51 away from the valve core 3 is provided with a top hole 53. The top hole 53 , the diameters of the middle hole 51 and the bottom hole 52 increase sequentially.

A balance hole 32 is provided on the end surface of the valve core 3 close to the push rod 4 , one end of the balance hole 32 communicates with the bottom hole 52 , and the other end of the balance hole 32 communicates with the second oil passage 31 .

One end of the valve sleeve 1 shrinks inwardly to form a stepped surface 12 , one end of the spring 2 is elastically connected to the valve core 3 , and the other end of the spring 2 is elastically connected to the stepped surface 12 .

One end of the spool 3 is provided with a blind hole 33 inserted by the spring 2; the first oil passage 30 includes a first annular groove 34 located on the outer peripheral surface of the spool 3, and the bottom surface of the first annular groove 34 is provided with The first through hole 35, the first through hole 35 communicates with the blind hole 33; the second oil passage 31 includes a second annular groove 36 located on the outer peripheral surface of the valve core 3, and a second annular groove 36 is arranged on the bottom surface of the second annular groove 36. The through hole 37 , the second through hole 37 communicates with the bottom surface of the blind hole 33 .

The control method of the one-way control valve of the axial plunger pump achieves the required relief pressure of the one-way control valve by presetting the stiffness of the spring 2, that is, when the required high-pressure relief pressure changes, by Just replace the spring 2 with different rigidities.

Working principle: When installed in the axial piston pump, the lower end of the valve sleeve 1 (that is, the end where the spherical surface is located) is located outside the working cavity of the axial piston pump and forms the inlet of the oil, and other parts are inserted into the axial piston pump. In the plunger pump, the first annular groove 34 , the second annular groove 36 and the top hole 53 are located in the working cavity of the axial piston pump.

In the initial state, under the elastic force of the spring 2, the spool 3 abuts against the lower end surface of the plug 5. At this time, the second annular groove 36 is located at the replenishment channel 11, and the working volume passes through the replenishment channel 11, the second The second annular groove 36, the second through hole 37, and the blind hole 33 are in communication with the valve sleeve 1, while the first annular groove 34 is located between the liquid replenishment channel 11 and the liquid discharge channel 10, and the first annular groove 34 is not connected to the liquid replenishment channel 11. When the external oil enters from the lower end of the valve sleeve 1, the external oil smoothly enters into the working chamber to replenish the working chamber. The flow enters the working volume.

With the work of the axial piston pump, when the oil pressure in the working chamber increases to a certain level, the ejector rod 4 moves downward under the action of the oil pressure in the working chamber, and the ejector rod 4 pushes the valve core 3 to overcome the spring The spring moves down. When the spool 3 moves a certain distance, the second annular groove 36 is disconnected from the replenishment hole 11, and the external oil cannot enter the working cavity, and the one-way valve function of the one-way control valve is in a closed state, and the external oil cannot into the working chamber. As the oil pressure in the working chamber continues to increase, the spring 2 is further compressed, and the spool 3 continues to move down until the pressure in the working chamber reaches the set overflow pressure, and the first annular groove 34 moves down to It communicates with the drain hole 10, and the oil in the working chamber is discharged from the lower end of the valve sleeve 1 through the drain hole 10, the first annular groove 34, the first through hole 35, and the blind hole 33, and the overflow of the one-way control valve The function of the flow valve is opened, and the oil in the working chamber overflows out to realize decompression.

In the initial state, the spool 3 is in contact with the plug 5 under the pressure F2 of the spring 2, and the plug 5 gives the reaction force F1 of the spool 3, and the one-way control valve is in the open position of the one-way valve function. Then, the oil pressure in the working chamber forms a force F3 on the ejector rod 4, and the ejector rod 4 is forced to move down for h, and exerts a pressure F4 on the valve core 3. The spool 3 moves down the distance h by the pressure F4 of the ejector rod, and exerts pressure F5 on the spring, and the spring with a stiffness of K is contracted by the pressure F5 to a length of h. Under the action of F2 and F4, the spool 3 is in the position where the overflow valve function is turned on, and the high-pressure oil is discharged from the working chamber. F1=F2, F3=F4=F5.

The condition of the one-way valve function closing, the valve core 3 moves down the distance h≥the one-way valve orifice diameter D1 (that is, the communication distance between the replenishment hole 11 and the second annular groove 36 in the axial direction);

The opening condition of the high-pressure relief valve is that the valve core moves down a distance h≥the distance L between the one-way valve orifice and the high-pressure relief orifice (that is, the distance between the first annular groove 34 and the discharge channel 10 ).

Claims (6)

1. The utility model provides an axial plunger pump check valve which characterized in that: the valve comprises a valve sleeve (1), wherein a valve core (3) in sliding connection is arranged in the valve sleeve (1), a spring (2) connected with the valve sleeve (1) is arranged on one side of the valve core (3), a plug (5) is arranged on the other side of the valve core (3), a guide hole (50) is axially formed in the plug (5), and a push rod (4) is arranged in the guide hole (50);

the side wall of the valve sleeve (1) is provided with a liquid draining pore canal (10) and a liquid supplementing pore canal (11);

be equipped with first oil duct (30) and second oil duct (31) on case (3), the inner chamber of valve pocket (1) is all linked together to the one end of first oil duct (30) and the one end of second oil duct (31), and the other end of first oil duct (30) is located on the lateral wall of case (3) and is located between flowing back duct (10) and fluid replacement duct (11), and the other end of second oil duct (31) is located on the lateral wall of case (3) and communicates fluid replacement duct (11).

2. The axial plunger pump unidirectional control valve of claim 1, wherein: the guide hole (50) comprises a middle hole (51) which is slidably connected with the ejector rod (4), a bottom hole (52) is formed in one end, close to the valve core (3), of the middle hole (51), a top hole (53) is formed in one end, far away from the valve core (3), of the middle hole (51), and the diameters of the top hole (53), the middle hole (51) and the bottom hole (52) are sequentially increased.

3. The axial plunger pump unidirectional control valve of claim 2, wherein: the valve core (3) is provided with a balance hole (32) on the end face close to the ejector rod (4), one end of the balance hole (32) is communicated with a bottom hole (52), and the other end of the balance hole (32) is communicated with a second oil duct (31).

4. The axial plunger pump unidirectional control valve of claim 1, wherein: one end of the valve sleeve (1) is contracted inwards to form a step surface (12), one end of the spring (2) is elastically connected to the valve core (3), and the other end of the spring (2) is elastically connected to the step surface (12).

5. The axial plunger pump unidirectional control valve of claim 1, wherein: one end of the valve core (3) is provided with a blind hole (33) which is inserted by the spring (2); the first oil duct (30) comprises a first annular groove (34) positioned on the outer peripheral surface of the valve core (3), a first through hole (35) is formed in the bottom surface of the first annular groove (34), and the first through hole (35) is communicated with the blind hole (33); the second oil duct (31) comprises a second annular groove (36) positioned on the outer peripheral surface of the valve core (3), a second through hole (37) is formed in the bottom surface of the second annular groove (36), and the second through hole (37) is communicated with the bottom surface of the blind hole (33).

6. The control method of the one-way control valve of the axial plunger pump according to any one of claims 1 to 5, characterized by: the required overflow pressure of the one-way control valve is achieved by presetting the rigidity of the spring (2).

Images