CN221033050U

CN221033050U - Displacement control valve with power override negative control

Info

Publication number: CN221033050U
Application number: CN202321234693.1U
Authority: CN
Inventors: 樊百夫
Original assignee: Zhantuo Hydraulic Shanghai Co ltd
Current assignee: Zhantuo Hydraulic Shanghai Co ltd
Priority date: 2023-05-22
Filing date: 2023-05-22
Publication date: 2024-05-28
Anticipated expiration: 2033-05-22

Abstract

The utility model discloses a displacement control valve with power override negative control, which comprises: the negative power override control mechanism comprises a power adjusting spring and a first connector body and is used for adjusting the pump power according to the first pressure applied to the first connector body and the elasticity of the power adjusting spring. The hydraulic stroke control mechanism comprises an adjusting spring and a second connector body and is used for adjusting the pump displacement according to the second pressure applied to the second connector body and the elastic force of the adjusting spring. Further comprises: and the pressure cut-off control mechanism is used for opening or cutting off the displacement of the pump. The utility model can reduce the cost.

Description

Displacement control valve with power override negative control

Technical Field

The utility model belongs to the field of hydraulic control valves, in particular to a displacement control with power negative control, which is applied to a closed variable plunger pump and is a pump control valve.

Background

The LG1DH type control valve has a pressure cut-off function, a negative power override control function and a hydraulic stroke control function.

Pressure cutoff is a type of pressure control where the pump displacement is returned to a minimum when the system pressure is above a set point. The negative power override is controlled by external pilot pressure, the external pilot pressure acts on the regulating spring of the power regulating mechanism, and the applied force is opposite to the acting force of the regulating spring, so that the function of power negative control is achieved. The hydraulic stroke control may steplessly limit or vary the displacement of the pump throughout the control range.

At present, LG1DH type control valves are not available in China. If a user needs this type of control valve, only foreign products can be purchased. However, such control valves are expensive and add significant cost to the user.

Disclosure of utility model

The utility model aims to provide a displacement control valve with power override negative control, which can reduce cost.

The utility model provides a displacement control valve with power override negative control, comprising:

The negative power override control mechanism comprises a power adjusting spring, a reset spring and a first connector body, and is used for adjusting pump power according to first pressure applied to the first connector body and elasticity of the power adjusting spring and the reset spring.

The hydraulic stroke control mechanism comprises a first spring and a second connector body and is used for realizing adjustment of pump displacement according to second pressure applied to the second connector body and elasticity of the adjusting spring.

Further, the negative power override control mechanism comprises a screwing adjusting screw, a power adjusting spring, a piston, a first pin, a rocker arm, a power control valve core and a second pin, wherein the screwing adjusting screw is used for extruding the power adjusting spring, and the elastic force of the power adjusting spring acts on one side of the rocker arm through the piston and the first pin; the elastic force of the return spring acts on the other side of the rocker arm through the power control valve core and the second pin.

Further, the negative power override control mechanism further comprises a plunger rod assembly, the plunger rod assembly applies thrust to the rocker arm, the rocker arm is provided with a rotating shaft, and the contact position of the plunger rod assembly and the rocker arm and the contact position of the first pin and the rocker arm are distributed on two sides of the rotating shaft.

Specifically, a first pressure of the first fitting body is applied to the piston.

Specifically, the piston includes a third step having a diameter smaller than the diameter of the second step.

In particular, the power control piston core is drilled.

Further, the hydraulic stroke control mechanism includes: the pressure of the first spring acts on one side of the control valve core through the first spring seat. The pressure of the plunger acts on the other side of the control valve core. The pressure of the pump outlet acts on the plunger.

Further, the hydraulic stroke control mechanism further includes: valve housing and hydraulic valve cap. The control valve core is arranged in a central hole of the valve sleeve, and the valve sleeve is fixed by the hydraulic valve cover.

Further, the method further comprises the following steps: pressure cut-off control mechanism. The pressure cut-off control mechanism is used for opening or cutting off the displacement of the pump.

Specifically, the pressure cutoff control mechanism includes: the second spring, the third spring, the pressure cut-off case, second elasticity seat, screw adjusting screw is used for extrudeing second spring and third spring, the pressure of second spring, third spring passes through the second spring holder is acted on one side of pressure cut-off case. The first pressure acts on the other side of the pressure shut-off spool.

Compared with the prior art, the utility model has at least the following beneficial effects:

The utility model provides an LG1DH type plunger pump displacement control valve with power override negative control. The external control oil with certain pressure is introduced through the first connector body, the power of the pump is reduced, and the higher the pressure of the external control oil of the first connector body is, the lower the power of the pump is. And introducing external control oil with certain pressure through the second joint body. The second joint body controls the pressure of the oil to rise, and the pump swings to a larger displacement. When the system pressure of the present utility model is greater than the pressure cutoff set point, the pressure is cut off and the displacement of the pump is minimized.

Drawings

In order to more clearly illustrate the embodiments of the present utility model or the technical solutions in the prior art, the drawings that are required to be used in the embodiments or the description of the prior art will be briefly described below, and it is obvious that the drawings in the following description are only embodiments of the present utility model, and that other drawings can be obtained according to the provided drawings without inventive effort for a person skilled in the art.

Fig. 1 is a right side view of a displacement control valve with power override negative control.

FIG. 2 is a schematic cross-sectional view of a displacement control valve with power override along line AA.

Fig. 3 is a schematic cross-sectional view of a displacement control valve with power override control along line BB.

1: An adjusting screw; 3: adjusting the rod sleeve; 5: a power adjustment spring; 7: a first connector body; 8: a power regulating piston sleeve; 9: a piston; 10: a first pin; 11: a valve body; 12: a second pin; 13: a power control spool; 15: a return spring; 16: a screw plug; 17: a hydraulic valve cover; 18: a screw; 20: a plunger; 21: a control valve core; 22: a valve sleeve; 23: a first spring seat; 24: a first spring; 25: a piston rod assembly; 26: a piston sleeve; 29: a rocker arm; 31: an adjusting nut; 32: a second spring; 33: a third spring; 34: a second spring seat; 35: a pressure cut-off valve core; 36: a control oil passage of the pump displacement control chamber; 37: a high pressure oil passage at the pump outlet; 38: and a pump outlet.

Detailed Description

A displacement control valve with power override control of the present utility model will be described in more detail below in conjunction with the schematic drawings, in which preferred embodiments of the present utility model are shown, it being understood that one skilled in the art could modify the utility model described herein while still achieving the advantageous effects of the utility model. Accordingly, the following description is to be construed as broadly known to those skilled in the art and not as limiting the utility model.

It is noted that relational terms such as first and second, and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Moreover, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.

The utility model is more particularly described by way of example in the following paragraphs with reference to the drawings. The advantages and features of the present utility model will become more apparent from the following description. It should be noted that the drawings are in a very simplified form and are all to a non-precise scale, merely for convenience and clarity in aiding in the description of embodiments of the utility model.

Referring to fig. 1, in this embodiment, a displacement control valve with power override negative control is provided, including:

The power control means that the displacement of the pump is changed along with the change of the working pressure, and as a result, the product of the pressure and the flow tends to be a fixed value, so that the constant power control is realized.

Wherein the height of the device is schematically shown in fig. 1 as 86.9cm, it will be appreciated that this is not to be taken as a particular limitation of the application, and that the person skilled in the art may adjust the device according to the actual situation, e.g. its height may be between 50 and 100cm, etc.

Further, the negative power override control mechanism comprises an adjusting screw 1, a power adjusting spring 5, a piston 9, a first pin 10, a rocker arm 29, a power control valve core 13 and a second pin 12, the adjusting screw 1 is screwed for pressing the first spring, and the elastic force of the power adjusting spring 5 acts on one side of the rocker arm 29 through the piston 9 and the first pin 10. The elastic force of the return spring 15 acts on the other side of the rocker arm 29 through the power control valve spool 13 and the second pin 12.

Further, the negative power override mechanism further includes a plunger rod assembly 25 that applies a pushing force to the rocker arm 29, the rocker arm 29 having a rotation axis, the contact of the plunger rod assembly 25 with the rocker arm 29 and the contact of the first pin 10 with the rocker arm 29 being distributed on both sides of the rotation axis.

Specifically, referring to fig. 2, the adjustment screw 1 is tightened to cause the power adjustment spring 5 to generate a constant compressive force that acts on the rocker arm 29 via the first pin 10. The power control spool 13 is pressed against the rocker arm by the second pin 12 under the pre-compression force of the return spring 15.

Referring to fig. 2, when the power control is in an initial state, the compression force of the power adjustment spring 5 sequentially passes through the piston 9, the first pin 10, the rocker arm 29, and the second pin 12 acts on the power control spool 13. At this time, the oil passage controlled by the power control valve core 13, that is, the control oil passage 36 of the pump displacement control chamber is communicated with the casing of the pump, the pressure of the pump displacement control chamber is minimum, and the pump displacement is at a maximum.

Referring to fig. 2, the pressure of pump outlet 38 acts on plunger rod assembly 25, plunger rod assembly 25 is pushed upward, and rocker arm 29 is subjected to a thrust force that turns to the left. By the arm conversion, the thrust force exerted by the rocker arm 29 is ultimately applied to the first pin 10, the piston 9 and the power adjustment spring 5.

Specifically, when the pressure of the pump outlet 38 is greater than a certain value, that is, when the rocker arm 29 receives a thrust force to rotate leftward greater than the compression force of the power adjustment spring 5, the power adjustment spring 5 is compressed to shorten, the piston 9 and the first pin 10 move leftward, and the rocker arm 29 receives a thrust force to rotate leftward. Simultaneously, the power control valve core 13 moves leftwards under the action of the precompression force of the return spring 15, and the other two oil channels controlled by the power control valve core 13, namely a high-pressure oil channel 37 connected with a pump outlet, are communicated with a control oil channel 36 connected with a pump displacement control cavity, so that the pump displacement is reduced.

Specifically, as the operating pressure of the pump outlet 38 increases, the power control spool 13 moves to the left, causing the pressure of the variable chamber to increase and the pump displacement to decrease.

In another embodiment of the utility model, when the device requires reduced power use, an external pressure is introduced from the Xr port in the figure (i.e. the first connector body 7), which external pressure is supplied by the customer, i.e. the first pressure of the first connector body 7, which acts on the end face of the piston 9 on the right side of the large step, so that the piston 9 is subjected to a thrust force to the left, thereby reducing the thrust force exerted on the rocker arm 29.

The power control spool 13 eventually moves to the left under the force of the return spring 15 due to the leftward rotation of the rocker arm 29 by the leftward thrust decrease. The two oil channels controlled by the power control valve core 13, namely a high-pressure oil channel 37 connected with a pump outlet, are communicated with a control oil channel 36 connected with a pump displacement control cavity, so that the pressure of a variable cavity is increased, the pump displacement is reduced, the power is reduced, and the negative power control is realized.

The higher the first pressure to which the first joint body 7 is subjected, the greater the power reduction amplitude.

Specifically, the first pressure of the first joint body 7 is applied to the piston 9.

In particular, the piston 9 comprises three steps, the diameter of the third step being smaller than the diameter of the second step.

In particular, the piston 9 is core-drilled.

In another embodiment of the present utility model, there is provided a displacement control valve with power override negative control, including:

The hydraulic stroke control mechanism comprises a first spring and a second connector body and is used for realizing adjustment of pump displacement according to second pressure applied to the second connector body and elasticity of the mechanical adjusting spring.

Further, the hydraulic stroke control mechanism includes: the pressure of the first spring 24 acts on one side of the control valve core 21 through the first spring seat 23, and the control valve core 21, the plunger 20, the first spring seat 23, and the first spring 24. The pressure of the plunger 20 acts on the other side of the control spool 21. The second pressure of the second joint acts on the plunger 20.

Further, the hydraulic stroke control mechanism further includes: a valve housing 22 and a hydraulic valve cap 17. The control valve core 21 is installed in the central hole of the valve sleeve 22, and the valve sleeve 22 is fixed by the hydraulic valve cover 17.

Specifically, referring to fig. 2, the hydraulic valve cap 17 is fixed to the valve body 11 by a screw, the control valve core 21 is installed in the center hole of the valve sleeve 22, and the valve sleeve 22 is fixed in the valve body hole by the hydraulic valve cap 17. The left side of the control valve core 21 is connected with a piston sleeve 26 through a first spring seat 23 and a first spring 24. The right side of the control valve core 21 is connected together through a plunger 20 and a screw 18.

In one embodiment of the present utility model, when the second joint body (i.e., the Xh port shown in fig. 2) does not provide pressure, the control spool 21 is placed at the rightmost position by the pressure of the first spring 24, at this time, two oil passages controlled by the control spool 21, that is, the high pressure oil passage 37 connected to the pump outlet is communicated with the control oil passage 36 connected to the pump displacement control chamber, and the pressure of the high pressure oil is directly introduced into the displacement control chamber so that the displacement of the pump is zero.

In one embodiment of the present utility model, when the second connector body provides pressure, the pressure acts on the plunger 20 to generate a leftward pushing force, pushing the control valve spool 21 to move leftward against the pressure of the first spring 24. After the valve core moves leftwards, an oil port between the pump outlet 38 and the variable cavity of the plunger pump is reduced, so that the pressure of the variable cavity is reduced, and the displacement of the plunger pump is increased.

The displacement of the plunger pump is in direct proportion to the external pressure value of the second joint body, and different second pressures correspond to different displacements, so that the hydraulic stroke control of the pump is realized.

and the pressure cut-off control mechanism is used for opening or cutting off the displacement of the pump.

Specifically, the pressure cutoff control mechanism includes: the second spring 32, the third spring 33, the pressure cut-off valve core and the second elastic seat 34 are used for pressing the second spring 32 and the third spring 33 by screwing the adjusting screw 1, and the pressure of the second spring 32 and the third spring 33 acts on one side of the pressure cut-off valve core 35 through the second spring seat 34. The first pressure acts on the other side of the pressure cutoff valve core 35.

Specifically, referring to fig. 3, an adjusting nut 31 is screwed to the valve body 11. The pressure cutoff valve body 35 is connected to the second spring seat 34, the second spring 32, the third spring 33, and the adjusting screw 1, and is installed in the pressure cutoff valve hole. The pressure cutoff valve element 35 is abutted against the bottom of the valve hole by being pressed by the second spring 32 and the third spring 33.

Referring to fig. 3, the pressure cut-off value is set by the adjusting screw 1 of the pressure cut-off mechanism, and the pressure cut-off function determines the maximum working pressure of the equipment in operation, so as to protect the system and the host.

In one embodiment of the utility model, the system operates in a power control state when the pressure of pump outlet 38 does not reach a pressure cutoff value. As the pressure of pump outlet 38 approaches the pressure cutoff value, the pump displacement begins to decrease. After the pressure at the pump outlet 38 continues to rise to the pressure cutoff set point, the pump enters a cutoff state where the displacement of the pump becomes zero and the pressure at the pump outlet is maintained at the pressure cutoff set point.

In another embodiment of the utility model, when the pump is in a pressure cut-off state, the output power of the pump also tends to zero as the output flow of the pump tends to zero, and the power control at this time is disabled, i.e., the pressure cut-off function takes precedence over the power control function.

Specifically, referring to fig. 3, the left end surface of the pressure cutoff valve core 35 (i.e., the bottom of the valve hole) communicates with the pump outlet through a process hole in the valve body 11. The adjusting screw 1 is screwed, the second spring 32 and the third spring 33 are compressed to generate compression force, and the spring force acts on the pressure cut-off valve core 35 through the second spring seat 34, so that the left end face of the pressure cut-off valve core 35 is tightly pressed against the bottom of the valve hole.

When the pressure of the pump outlet 38 acting on the left end surface of the pressure cut-off valve spool 35 exceeds the compression forces of the second spring 32 and the third spring 33, the pressure cut-off valve spool 35 moves rightward, causing the pump variable chamber to be in pressure communication with the outlet of the pump, and the pressure of the variable chamber increases, so that the displacement of the pump decreases. As the pressure at the pump outlet 38 continues to rise, the pressure shut-off spool continues to move to the right, the variable chamber pressure continues to increase, the pump displacement continues to decrease, and eventually approaches zero, thereby effecting pressure shut-off.

In summary, in the displacement control valve with power override control proposed in the present embodiment, the higher the pressure of the first joint body of the negative power override control mechanism, the larger the power reduction amplitude. The displacement of the plunger pump of the hydraulic stroke control mechanism is in direct proportion to the second pressure value of the second joint body, and different second pressures correspond to different displacements, so that the hydraulic stroke control of the pump is realized. The pressure cut-off control mechanism continuously increases the pump outlet pressure, the cut-off pressure cut-off valve core continuously moves rightwards, the pressure of the variable cavity continuously increases, the pump discharge capacity continuously decreases, and finally the pressure tends to zero, so that the pressure cut-off is realized.

It will be apparent to those skilled in the art that various modifications and variations can be made to the present utility model without departing from the spirit or scope of the utility model. Thus, it is intended that the present utility model also include such modifications and alterations insofar as they come within the scope of the appended claims or the equivalents thereof.

Claims

1. A displacement control valve with power override control, comprising:

The negative power override control mechanism comprises a power adjusting spring, a reset spring and a first connector body, and is used for adjusting pump power according to first pressure applied to the first connector body and elasticity of the power adjusting spring and the reset spring;

2. A displacement control valve with power override according to claim 1, characterized in that the negative power override control mechanism comprises an adjusting screw (1), a power adjusting spring (5), a piston (9), a first pin (10), a rocker arm (29), a power control valve core (13), a second pin (12), the adjusting screw (1) being screwed for pressing the first spring, the elastic force of the power adjusting spring (5) acting on one side of the rocker arm (29) through the piston (9), the first pin (10); the elastic force of the return spring (15) acts on the other side of the rocker arm through the power control valve core (13) and the second pin (12).

3. A displacement control valve with power override as claimed in claim 2, wherein the negative power override control mechanism further comprises a plunger rod assembly (25) that applies a pushing force to the rocker arm, the rocker arm having a rotational axis, the contact of the plunger rod assembly with the rocker arm and the contact of the first pin with the rocker arm being split on either side of the rotational axis.

4. A displacement control valve with power override as recited in claim 2, wherein the first pressure of the first fitting body is applied to the piston.

5. A displacement control valve with power override as recited in claim 2, wherein the piston includes a three-stage step having a diameter less than a diameter of the second-stage step.

6. A displacement control valve with power override as recited in claim 2, wherein the power control piston core is bored.

7. A displacement control valve with power override as recited in claim 1, wherein the hydraulic travel control mechanism comprises: the pressure of the first spring (24) acts on one side of the control valve core (21) through the first spring seat (23); the pressure of the plunger (20) acts on the other side of the control valve core (21); the pressure at the pump outlet acts on the plunger.

8. A displacement control valve with power override as recited in claim 7, wherein the hydraulic travel control mechanism further comprises: a valve housing and a hydraulic valve cover; the control valve core is arranged in a central hole of the valve sleeve, and the hydraulic valve cover (17) is used for fixing the valve sleeve (22).

9. A displacement control valve with power override as recited in claim 2, further comprising: and the pressure cut-off control mechanism is used for opening or cutting off the displacement of the pump.

10. A displacement control valve with power override as recited in claim 9, wherein the pressure cutoff control mechanism comprises: the second spring, the third spring, the pressure cut-off valve core and the second spring seat; screwing the adjusting screw (1) for pressing the second spring (32) and the third spring (33), wherein the pressure of the second spring (32) and the third spring (33) acts on one side of the pressure cutting valve core (35) through the second spring seat (34); the first pressure acts on the other side of the pressure shut-off spool (35).