CN111664136A

CN111664136A - Load compensation balance valve

Info

Publication number: CN111664136A
Application number: CN202010447759.XA
Authority: CN
Inventors: 姜伟; 王震山; 王清送; 张夕航; 唐红彩; 张晓磊; 史浙安; 陈钊汶; 王哲亮; 林俊策
Original assignee: Shanghai Shengbang Hydraulic Co ltd; Xuzhou Shengbang Machinery Co Ltd; Zhejiang Sunbun Technology Co Ltd; Sunbun Group Co Ltd
Current assignee: Shanghai Shengbang Hydraulic Co ltd; Xuzhou Shengbang Machinery Co Ltd; Zhejiang Sunbun Technology Co Ltd; Sunbun Group Co Ltd
Priority date: 2020-05-25
Filing date: 2020-05-25
Publication date: 2020-09-15
Anticipated expiration: 2040-05-25
Also published as: CN111664136B

Abstract

A load compensation balance valve. The problem of current gravity system's balanced valve leveling speed regulating ability poor in the in-service use is solved. The valve comprises a valve body and a valve core, wherein a first oil port and a second oil port are arranged on the valve body, a control cavity and a spring cavity are arranged at two ends of the valve core, a first passage is arranged on the valve core and communicated with the first oil port, the valve core has a first state that the first oil port is isolated from the second oil port and a second state that the first oil port is communicated with the second oil port, when the valve core is in the second state, pressure oil of the first oil port is communicated with the spring cavity through the first passage and a first throttling port, and the spring force of the spring cavity and the pressure of the spring cavity for picking up the pressure oil of the first oil port are mutually matched with each other and mutually balance the control force of the control cavity to control the opening of the valve core. The invention also has the advantages of simple structure, convenient assembly, reliable action, long service life and the like.

Description

Load compensation balance valve

Technical Field

The invention relates to a hydraulic control system of engineering machinery, in particular to a load compensation balance valve.

Background

Along with the requirement of the building industry on efficiency improvement, the demand of aerial work platform equipment is more and more extensive. It is often used to perform high-altitude operations such as exterior wall maintenance, high-altitude buildings and street lamp installation. The existing aerial work platform product amplitude-variable lowering system has two amplitude-variable lowering modes of gravity falling and power falling, and the two amplitude-variable lowering modes respectively have own advantages and disadvantages.

In many arm support type engineering machinery, along with the change of an arm support angle, the load of an oil cylinder for supporting the arm support changes along with the change, and generally, the lower the arm support angle is, the larger the load is; the higher the boom angle, the smaller the load. The oil cylinders of the hydraulic systems are generally provided with balance valves, and the balance valves play a role in load maintenance in a static state, so that oil drainage of the oil cylinders is prevented, and further, the overturning of the arm support structure is prevented, so that dangers are avoided; when the arm support falls, the falling speed of the arm support is controlled through the throttling effect of the balance valve, so that the falling speed of the arm support can be controlled according to the requirement of an operator.

The control of the falling speed of the arm support is to control the oil quantity of a load cavity of an oil cylinder, and generally has two modes, one mode is control through an external control pilot low-pressure oil source, namely, only a balance valve is opened, and the flow is generated on the balance valve by means of the gravity of the arm support; one is a high-pressure oil source, which acts on the other cavity of the oil cylinder, controls the control port of the balance valve, opens the balance valve, and forms a closed loop, namely a power falling mode; the two modes of amplitude lowering have own advantages and disadvantages.

The power falling mode has the characteristic of high efficiency, and the power lowering system has the defect that certain pressure oil is needed to open the balance valve on the corresponding oil return path through the control port in the extending and retracting processes of the oil cylinder, so that the energy consumption is increased; meanwhile, in the process of amplitude-variable lowering, the load acting force changes greatly, so that the balance valve is easy to shake, and the amplitude-variable oil cylinder falls unstably. Gravity whereabouts mode has steadily, the characteristics that the energy consumption is low, and gravity is transferred the system shortcoming lies in, and the influence that receives the load is transferred to the gravity of the width of cloth hydro-cylinder simultaneously, and when the load was great, along with diminishing of cantilever crane angle, the effort that gravity was applyed to the width of cloth hydro-cylinder is great, and the falling speed is relatively very fast, and corresponding flow through balanced valve this moment also can increase, in case danger such as the too fast will take place out of control, causes certain economic loss and casualties. When the load is smaller, the acting force applied to the amplitude variation oil cylinder by gravity is smaller, the falling speed is very slow, and the working efficiency is reduced.

Disclosure of Invention

In order to solve the problem that the balance valve of the existing gravity system in the background technology is poor in speed leveling capability in the actual use process, the invention provides the load compensation balance valve.

The technical scheme of the invention is as follows: the utility model provides a load compensation balance valve, includes valve body and case, the valve body on be equipped with first hydraulic fluid port and second hydraulic fluid port, the both ends of case are equipped with control chamber and spring chamber, the case on be equipped with first passageway, first passageway and first hydraulic fluid port be linked together, the case have make first hydraulic fluid port and second hydraulic fluid port isolated first state and make first hydraulic fluid port and second state that the second hydraulic fluid port is linked together, the case when being in the second state, the pressure oil of first hydraulic fluid port be linked together through first passageway, first choke and spring chamber, the spring force in spring chamber, the pressure that the spring chamber picked up first hydraulic fluid port pressure oil mutually support with the opening of the control chamber's control force is balanced each other control case.

As an improvement of the invention, a first valve sleeve is arranged in the valve body, a load pickup port is arranged on the first valve sleeve, and the load pickup port enables pressure oil of the first throttling port to be communicated with the spring cavity when the valve core is in the second state.

As a further improvement of the invention, an oil return port is arranged on the valve body, and an oil outlet of the load pickup port is communicated with the oil return port.

As a further improvement of the invention, the valve body is provided with a reversing valve and a first damping hole, the reversing valve is arranged at an oil outlet of the load pickup port, and the reversing valve is provided with a first position enabling pressure oil at the load pickup port to be communicated with the oil return port and a second position enabling the pressure oil at the load pickup port to be communicated with the oil return port through the first damping hole.

As a further improvement of the invention, the first throttling opening is a fixed throttling groove.

As a further improvement of the present invention, the first orifice is a variable orifice groove, and the opening size of the variable orifice groove changes with a change in the position of the valve body when the valve body is in the second state.

As a further improvement of the invention, the first throttling port is arranged on the outer surface of the valve core, and the first throttling port is in a bevel groove or triangular groove structure.

As a further improvement of the invention, the valve body is provided with a second valve sleeve, the second valve sleeve is arranged at one end of the valve core and is mutually matched with the valve body to form the spring cavity, and the valve core and the second valve sleeve are axially, slidably and circumferentially matched in a rotating manner.

As a further improvement of the invention, the valve further comprises a positioning piece, and a positioning notch which is matched with each other and used for accommodating the positioning piece is arranged between the end part of the valve core and the end part of the second valve sleeve.

As a further improvement of the invention, a control piston is arranged in the control cavity, the control piston comprises a pushing end abutting against the valve core and a control end for receiving control oil pressure, the diameter of the control end of the control piston is larger than that of the valve core, and a second damping hole for communicating the control cavity with the oil return port is arranged on the control piston.

The invention has the advantages that the compensation function is set, the speed can be adjusted in a compensation mode, namely, the higher the load pressure is, the lower the speed is, the dynamic balance is realized under the condition of not changing the pressure of the external control oil source, and the product acts stably and reliably. The invention also has the advantages of simple structure, convenient assembly, reliable action, long service life and the like.

Drawings

Fig. 1 is a schematic structural diagram of an embodiment of the present invention.

FIG. 2 is a schematic view of the half-section structure of FIG. 1.

Fig. 3 is a partially enlarged view of the first orifice 22 of fig. 2.

Fig. 4 is a schematic structural diagram of the valve core 2 in fig. 2.

Fig. 5 is a hydraulic schematic diagram of a first embodiment of the present invention.

Fig. 6 is a hydraulic schematic diagram of a second embodiment of the present invention.

In the figure, 1, a valve body; 11. a diverter valve; 2. a valve core; 21. a first channel; 22. a first orifice; 3. a control chamber; 4. a spring cavity; 5. a first valve housing; 51. a load pick-up port; 6. a first orifice; 7. a second valve housing; 8. a positioning member; 9. a control piston; 91. a pushing end; 92. a control end; 93. a second orifice; A. a first oil port; B. a second oil port; l, an oil return port.

Detailed Description

The embodiments of the invention will be further described with reference to the accompanying drawings in which:

as shown in fig. 1 in conjunction with fig. 2 to 6, a load compensation balance valve includes a valve body 1 and a valve core 2, the valve body 1 is provided with a first oil port A and a second oil port B, two ends of the valve core 2 are provided with a control cavity 3 and a spring cavity 4, the valve core 2 is provided with a first channel 21, the first channel 21 is communicated with a first oil port A, the valve core 2 has a first state that the first oil port A is isolated from the second oil port B and a second state that the first oil port A is communicated with the second oil port B, when the valve core 2 is in the second state, the pressure oil of the first oil port A is communicated with the spring cavity 4 through the first channel 21 and the first throttling port 22, the spring force of the spring cavity 4 and the pressure of the pressure oil of the first oil port A picked up by the spring cavity 4 are matched with each other, and the opening of the control valve core 2 is balanced with the control force of the control cavity 3. The invention has the advantages that the compensation function is set, the speed can be adjusted in a compensation mode, namely, the higher the load pressure is, the lower the speed is, the dynamic balance is realized under the condition of not changing the pressure of the external control oil source, and the product acts stably and reliably. The invention also has the advantages of simple structure, convenient assembly, reliable action, long service life and the like. According to the invention, load pressure oil is introduced into the spring cavity of the balance valve, so that when the swing arm is in a system under gravity and the load oil pressure rises along with the reduction of the angle, the speed can be regulated, and the damage to personnel and products caused by the over-high speed of the swing arm is avoided.

The valve body 1 is internally provided with a first valve sleeve 5, the first valve sleeve 5 is provided with a load pickup port 51, and the load pickup port 51 enables pressure oil of the first throttling port 22 to be communicated with the spring cavity 4 when the valve core 2 is in the second state. The valve body 1 is provided with an oil return port L, and an oil outlet of the load pickup port 51 is communicated with the oil return port L. Specifically, a first damping hole is formed in the valve body, and oil outlets of the load pickup port 51 are communicated through a first damping hole oil return port L. The difference between fig. 5 and 6 is whether a reversing valve is provided for control, the valve body 1 is provided with a reversing valve 11 and a first damping hole 6, the reversing valve 11 is provided at an oil outlet of the load pickup port 51, and the reversing valve 11 has a first position at which the pressure oil at the load pickup port 51 is communicated with the oil return port L and a second position at which the pressure oil at the load pickup port 51 is communicated with the oil return port L through the first damping hole 6. Specifically, the reversing valve is a two-position three-way electromagnetic valve, so that the compensation electric selection can be realized by switching on and off the electromagnetic valve. When compensation is not needed, the electromagnetic valve is powered off and corresponds to the falling speed of the oil cylinder (at this time, the first damping hole can be understood to be large enough to enable pressure oil at the oil outlet of the load pickup port 51 to be directly communicated with the oil return port, namely no pressure oil enters the spring cavity); when compensation is needed, the electromagnetic valve is electrified, and the speed compensation is correspondingly carried out (the structure can be simply understood as the attached figure 2). A bridge circuit is formed between the first throttling port and the first damper, and pressure (called compensation pressure) between the first throttling port and the first damper acts on a spring cavity of the balance valve, so that a valve core of the balance valve is under the action of both the spring force and the compensation pressure, and the pressure of the spring cavity is related to the displacement and the load of the valve core, so that the compensation effect is realized. Specifically, the first damping hole is arranged, so that the compensation amount can be adjusted through the first damping hole, and the smaller the first damping hole is, the earlier the compensation is; the larger the first damping hole is, the later the compensation is, namely the first damping hole can be set into a variable damping hole, and the pressure oil quantity entering the spring cavity can be adjusted by adjusting the first damping hole.

The balance valve has A, B, K, L four oil ports, and of course, the balance valve can be adjusted according to requirements, for example, a pressure measuring port is added, and a heat-sensitive overflow valve can be added at the port A according to requirements. Specifically, an oil return port L is arranged behind the first damping hole, and the port L is directly communicated with an oil tank without any back pressure. Of course, if it is necessary to keep the spring chamber full, for example, to charge the spring chamber, the back pressure may be increased appropriately, so as to improve the responsiveness of compensation, and the K port is the control pressure port of the control chamber. Typically, port a is connected to the load cylinder and port B is connected to the tank.

The first orifice 22 is a fixed orifice groove. Specifically, the first orifice 22 is a variable orifice groove, and the opening size of the variable orifice groove changes with the position of the valve element 2 when the valve element 2 is in the second state. Specifically, the first throttling opening can be a fixed throttling groove or a variable throttling groove, the fixed throttling groove is the throttling groove, the size of the throttling groove does not change along with the displacement, the variable throttling groove changing along with the displacement is different from the fixed throttling groove in compensation characteristics, the compensation characteristics of the variable throttling groove are influenced by pressure and displacement, and the fixed throttling groove is only influenced by the pressure.

The first throttling orifice 22 is arranged on the outer surface of the valve core 2, and the first throttling orifice 22 is in an inclined plane groove or triangular groove structure. Of course, the first restriction may have other configurations during actual production.

The valve body 1 is provided with a second valve sleeve 7, the second valve sleeve 7 is arranged at one end of the valve core 2 and is matched with the valve body 1 to form the spring cavity 4, and the valve core 2 and the second valve sleeve 7 are in axial sliding and circumferential rotation matching. Specifically, the invention further comprises a positioning piece 8, and a positioning notch which is matched with the end part of the valve core 2 and the end part of the second valve sleeve 7 for accommodating the positioning piece 8 is arranged between the end part of the valve core and the end part of the second valve sleeve. The variable throttling groove is an inclined groove on the valve core, the load picking port is a round hole, the main valve core can rotate 360 degrees in the assembling process, a steel ball positioning mode is designed in the patent, namely, half positioning notches (rectangular grooves) are respectively cut in the valve core and the second valve sleeve, and a positioning piece (steel ball) is arranged in the rectangular groove, so that the movement of the valve core is restrained by the positioning piece (steel ball), namely, the valve core is fixed in the circumferential direction and is free in the linear movement direction, so that the positioning relation between the first throttling port and the load picking port is ensured, and the picking of compensation pressure is ensured. The positioning structure design realizes the positioning function, has the function of an oil duct, and makes compensating pressure enter the spring cavity by means of the oil duct.

The control cavity 3 in be equipped with control piston 9, control piston 9 includes the control end 92 that pushes away with case 2 and be used for receiving the control oil pressure, the diameter of control end 92 of control piston 9 is greater than the diameter of case 2, control piston 9 on be equipped with the second damping hole 93 that is used for communicateing control cavity 3 and oil return opening L. The diameter of the control end 92 of the control piston 9 is larger than that of the valve core 2, so that the conditioning pressure of a spring of the spring cavity can be increased, and the pressure regulating interval is larger. The invention controls the movement of the valve core by controlling the piston, is convenient to control, and can also control the action of the valve core in other modes in the actual production process.

In the description of the present invention, it should be noted that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art. In addition, in the description of the present invention, "a plurality" means two or more unless otherwise specified.

The skilled person should understand that: although the invention has been described in terms of the above specific embodiments, the inventive concept is not limited thereto and any modification applying the inventive concept is intended to be included within the scope of the patent claims.

Claims

1. A load compensation balance valve comprises a valve body (1) and a valve core (2), and is characterized in that a first oil port (A) and a second oil port (B) are arranged on the valve body (1), a control cavity (3) and a spring cavity (4) are arranged at two ends of the valve core (2), a first channel (21) is arranged on the valve core (2), the first channel (21) is communicated with the first oil port (A), the valve core (2) has a first state enabling the first oil port (A) and the second oil port (B) to be separated and a second state enabling the first oil port (A) and the second oil port (B) to be communicated, when the valve core (2) is in the second state, pressure oil of the first oil port (A) is communicated with the spring cavity (4) through the first channel (21) and a first throttling port (22), and spring force of the spring cavity (4), The spring cavity (4) picks up the pressure of the pressure oil of the first oil port (A) and is matched with the control force of the control cavity (3) to balance the opening of the control valve core (2).

2. A load-compensating balancing valve according to claim 1, characterized in that the valve body (1) is provided with a first valve housing (5), the first valve housing (5) being provided with a load pick-up port (51), the load pick-up port (51) communicating the pressurized oil of the first restriction (22) with the spring chamber (4) when the spool (2) is in the second state.

3. A load compensating balance valve according to claim 2, characterized in that said valve body (1) is provided with an oil return port (L), and an oil outlet of said load pick-up port (51) is communicated with said oil return port (L).

4. A load-compensating balancing valve according to claim 3, characterized in that the valve body (1) is provided with a directional control valve (11) and a first damping hole (6), the directional control valve (11) is provided at the oil outlet of the load pick-up port (51), the directional control valve (11) has a first position at which the pressure oil at the load pick-up port (51) is communicated with the oil return port (L) and a second position at which the pressure oil at the load pick-up port (51) is communicated with the oil return port (L) through the first damping hole (6).

5. A load compensating balance valve according to claim 1 wherein the first restriction (22) is a fixed restriction slot.

6. A load compensating balance valve according to claim 1 wherein the first restriction (22) is a variable restriction recess, the opening of the variable restriction recess varying with the position of the spool (2) when the spool (2) is in the second state.

7. The load compensation balance valve according to claim 6, wherein the first orifice (22) is formed on the outer surface of the valve body (2), and the first orifice (22) has a bevel groove or triangular groove structure.

8. The load compensation balance valve according to claim 2, wherein the valve body (1) is provided with a second valve sleeve (7), the second valve sleeve (7) is arranged at one end of the valve core (2) and is matched with the valve body (1) to form the spring cavity (4), and the valve core (2) is axially slidably matched with the second valve sleeve (7) in a circumferential rotation manner.

9. A load-compensating balancing valve according to claim 8, further comprising a positioning member (8), wherein a positioning notch is provided between the end of the spool (2) and the end of the second valve sleeve (7) for receiving the positioning member (8).

10. The load compensation balance valve according to claim 3, wherein a control piston (9) is arranged in the control chamber (3), the control piston (9) comprises a pushing end (91) abutting against the valve core (2) and a control end (92) for receiving control oil pressure, the diameter of the control end (92) of the control piston (9) is larger than that of the valve core (2), and a second damping hole (93) for communicating the control chamber (3) with the oil return port (L) is formed in the control piston (9).