CN114321044A - Bucket rod control valve structure and excavator - Google Patents

Abstract

The invention relates to the technical field of excavators, and particularly discloses a bucket rod control valve structure and an excavator. The first valve core of the first control valve is provided with a rodless cavity which can be communicated with the first pressure source and the arm cylinder, the rodless cavity of the arm cylinder is communicated with a working position A1 of the oil tank, the working position A2 which can be disconnected from the rodless cavity, the first pressure source and the oil tank, the second valve core of the second control valve is provided with a working position B1 which is communicated with the second pressure source and the rodless cavity and is communicated with the regeneration port, and a working position B2 which can be disconnected from the rodless cavity, the first pressure source and the oil tank, when the arm is retracted, the second valve core is positioned at the working position B2, and the regeneration one-way valve allows oil to flow into an input port B1 which is communicated with the second pressure source through the regeneration port, so that the oil in the rod cavity can be filled into the rodless cavity, a regeneration cut-off valve is not needed, the regeneration back pressure can be reduced, and the energy efficiency can be improved.

Description

A stick control valve structure and excavator

technical field

The invention relates to the technical field of excavators, in particular to a structure of a stick control valve and an excavator.

Background technique

The hydraulic control system of the stick of the existing excavator is usually controlled by two pumps and two valve cores. Taking the stick cylinder as an example, two pumps provide hydraulic oil to the stick cylinder through two spools synchronously. During the recovery process of the stick, there may be positive pressure or negative pressure in the rodless cavity of the stick cylinder. It is necessary to supply oil to the oil inlet side of the rodless cavity from the hydraulic oil in the rod cavity through the oil return channel in the spool and the regeneration check valve. Not required when positive pressure. However, in order to avoid the shock phenomenon, it is usually necessary to add a regeneration cut-off valve on the oil return passage. When the negative pressure or small positive pressure in the rodless cavity, the regeneration cut-off valve is in the throttled open state, and the oil return back pressure is increased, which can To prevent the phenomenon of air suction and forward rush caused by the stick cylinder extending too fast; when there is positive pressure in the rodless cavity and the pressure is large, the regeneration cut-off valve is fully opened, and the throttling is no longer opened, thereby releasing the regeneration.

However, when the regenerative shut-off valve is throttled open, the back pressure of the oil return is high, the pressure loss is large, and the power loss is also large.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a stick control valve structure and an excavator, so as to solve the problem of large pressure loss caused by using a regeneration cut-off valve to open or cancel regeneration in the related art.

In one aspect, the present invention provides a stick control valve structure, the stick control valve structure includes:

The first control valve, the first control valve includes a first valve core, the first control valve has an input port A1, an oil return port A1, an output port A1 and an output port A2, and the input port A1 is used to communicate with the first control valve. A pressure source is connected, the oil return port A1 is used to communicate with the oil tank, the output port A1 is used to communicate with the oil port A, the output port A2 is used to communicate with the oil port B, and the oil port A is used to communicate with the bucket The rodless cavity of the rod cylinder communicates with the rod cavity of the stick cylinder, the oil port B communicates with the rod cavity of the stick cylinder, and the first valve core can be switched between the working position A1 and the working position A2. When the first valve When the spool is in the working position A1, the input port A1 communicates with the output port A1, and the oil return port A1 communicates with the output port A2; when the first spool is in the working position A2 , the input port A1, the oil return port A1, the output port A1 and the output port A2 are all closed;

The second control valve, the second control valve includes a second valve core, the first control valve has an input port B1, a regeneration port, an oil return port B1, an output port B1 and an output port B2, and the input port B1 is used for In order to communicate with the second pressure source, the oil return port B1 is used for communication with the oil tank, the output port B1 is used for communication with the oil port A, the output port B2 is used for communication with the oil port B, The second valve core can be switched between the working position B1 and the working position B2. When the second valve core is located at the working position B1, the input port B1 and the output port B1 are communicated, and the regeneration The port is connected to the output port B2, and the oil return port B1 is disconnected; when the second spool is at the working position B2, the input port B1, the regeneration port, and the oil return port B1. Both the output port B1 and the output port B2 are closed;

A regeneration check valve is provided between the regeneration port and the input port B1, and only allows oil to flow from the regeneration port to the input port B1.

As a preferred technical solution of the stick control valve structure, the first control valve further includes a first pilot hydraulic control end, and the first pilot hydraulic control end is used to drive the first valve core to move to the working position A1 , the first pilot hydraulic control end supplies pilot oil through the first oil supply device.

As a preferred technical solution of the stick control valve structure, the stick control valve structure further includes a first electric proportional flow valve disposed on the oil supply pipeline of the first pilot hydraulic control end.

As a preferred technical solution of the stick control valve structure, the second control valve further includes a second pilot hydraulic control end, and the second pilot hydraulic control end is used to drive the second spool to move to the working position B1 , the second pilot hydraulic control end supplies pilot oil through the second oil supply device.

As a preferred technical solution of the stick control valve structure, the stick control valve structure further includes a second electric proportional flow valve disposed on the oil supply pipeline of the second pilot hydraulic control end.

As a preferred technical solution of the stick control valve structure, the first valve core further has a working position A3, the working position A2 is located between the working position A3 and the working position A1, and the first valve core can Switching between the working position A1, the working position A2 and the working position A3, when the first valve core is in the working position A3, the input port A1 and the output port A2 are communicated, The oil return port A1 communicates with the output port A1.

As a preferred technical solution of the stick control valve structure, the second valve core further has a working position B3, the working position B2 is located between the working position B3 and the working position B1, and the second valve core can Switching between the working position B1, the working position B2 and the working position B3, when the second spool is in the working position B3, the input port B1 and the output port B2 communicate with each other, The oil return port B1 and the output port B2 communicate with each other, and the regeneration port is disconnected.

As a preferred technical solution of the stick control valve structure, the first control valve further includes a third pilot hydraulic control end, and the third pilot hydraulic control end is used to drive the first spool to move to the working position A3 , the second control valve further includes a fourth pilot hydraulic control end, the fourth pilot hydraulic control end is used to drive the second spool to move to the working position B3, the third pilot hydraulic control end and The fourth pilot hydraulic control end is supplied with pilot oil through the third oil supply device.

As a preferred technical solution of the stick control valve structure, the stick control valve structure further includes a load holding valve, one end of the load holding valve is communicated with the oil port B, and the other end of the load holding valve is respectively connected with the oil port B. The output port A2 and the output port B2 communicate with each other.

In another aspect, the present invention provides an excavator, including the stick control valve structure in any of the above solutions.

The beneficial effects of the present invention are:

The invention provides an arm control valve structure and an excavator. The arm control valve structure includes a first control valve, a second control valve and a regeneration check valve. The first control valve includes a first spool, the first control valve has an input port A1, an oil return port A1, an output port A1 and an output port A2, the input port A1 is used for communicating with the first pressure source, and the oil return port A1 is used for Connected with the oil tank, the output port A1 is used to communicate with the oil port A, the output port A2 is used to communicate with the oil port B, the oil port A is communicated with the rodless cavity of the stick cylinder, and the oil port B is connected with the rod cavity of the stick cylinder. Connected. The first spool can be switched between the working position A1 and the working position A2. When the first spool is in the working position A1, the input port A1 is communicated with the output port A1, and the oil return port A1 is communicated with the output port A2. When the spool is in the working position A2, the input port A1, the oil return port A1, the output port A1 and the output port A2 are all closed. The second control valve includes a second valve core. The first control valve has an input port B1, a regeneration port, an oil return port B1, an output port B1 and an output port B2. The input port B1 is used to communicate with the second pressure source, and the oil return port B1 is used to communicate with the oil tank, the output port B1 is used to communicate with the oil port A, and the output port B2 is used to communicate with the oil port B. The second spool can be switched between the working position B1 and the working position B2. When the second spool is in the working position B1, the input port B1 and the output port B1 communicate with each other, the regeneration port communicates with the output port B2, and the oil return port B1 Disconnected; when the second spool is at the working position B2, the input port B1, regeneration port, oil return port B1, output port B1 and output port B2 are all closed; regeneration check valve is set between the regeneration port and input port B1 and only allow the oil to flow from the regeneration port to the input port B1. When the second spool is in the working position B1, if the oil pressure in the rod chamber is greater than the oil pressure in the rodless chamber, the rod cylinder of the stick cylinder has a rod. The pressure oil in the cavity can also be supplemented to the input port B1 through the second valve core and the regeneration check valve, and then supplemented to the rodless cavity to avoid emptying. If the oil pressure in the rod chamber is lower than the oil pressure in the rodless chamber, the regeneration check valve remains closed. The structure of the stick control valve does not need to use the regeneration cut-off valve in the prior art, which can effectively reduce the regeneration back pressure and improve the energy efficiency, and the regeneration oil passage can be arranged outside the second valve core, and the regeneration flow will not be affected by the second valve. The effect of core strength.

Description of drawings

Fig. 1 is a structural schematic diagram 1 of a stick control valve structure in an embodiment of the present invention (the first valve core is located at the working position A2, and the second valve core is located at the working position B2);

2 is a second structural schematic diagram of the structure of the stick control valve in the embodiment of the present invention (the first valve core is located at the working position A1, and the second valve core is located at the working position B1);

3 is a third structural schematic diagram of the structure of the stick control valve in the embodiment of the present invention (the first valve core is located at the working position A1, and the second valve core is located at the working position B2);

FIG. 4 is a structural schematic diagram 4 of the structure of the stick control valve in the embodiment of the present invention (the first valve core is located at the working position A2, and the second valve core is located at the working position B1);

5 is a structural schematic diagram 5 of the structure of the stick control valve in the embodiment of the present invention (the first valve core is located at the working position A3, and the second valve core is located at the working position B3).

In the picture:

11. The first valve core; 12. The first pilot hydraulic control end; 13. The third pilot hydraulic control end;

21, the second valve core; 22, the second pilot hydraulic control end; 23, the fourth pilot hydraulic control end;

3. Regeneration check valve;

4. Load holding valve;

5. The first on-off control valve;

6. The second on-off control valve;

7. Stick cylinder; 71. With rod cavity; 72. Without rod cavity.

Detailed ways

The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are a part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. The indicated orientation or positional relationship is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the indicated device or element must have a specific orientation or a specific orientation. construction and operation, and therefore should not be construed as limiting the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed to indicate or imply relative importance. Wherein, the terms "first position" and "second position" are two different positions, and the first feature being "above", "over" and "above" the second feature includes the first feature being "over" the second feature Directly above and diagonally above, or simply means that the first feature is level higher than the second feature. The first feature is "below", "below" and "below" the second feature includes the first feature being directly below and diagonally below the second feature, or simply means that the first feature has a lower level than the second feature.

In the description of the present invention, it should be noted that the terms "installed", "connected" and "connected" should be understood in a broad sense, unless otherwise expressly specified and limited, for example, it may be a fixed connection or a detachable connection Connection, or integral connection; can be mechanical connection, can also be electrical connection; can be directly connected, can also be indirectly connected through an intermediate medium, can be internal communication between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood in specific situations.

The following describes in detail the embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals refer to the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary, only used to explain the present invention, and should not be construed as a limitation of the present invention.

In the stick cylinder in the prior art, during the recovery process of the stick, the rodless cavity of the stick cylinder may be either positive pressure or negative pressure. If the pressure is greater than the pressure of the rodless cavity of the stick cylinder, the hydraulic oil in the rod cavity needs to be replenished to the oil inlet side of the rodless cavity through the oil return channel in the valve core and the regeneration check valve. Not required when positive pressure. However, in order to avoid the shock phenomenon, it is usually necessary to add a regeneration cut-off valve on the oil return passage. When the negative pressure or small positive pressure in the rodless cavity, the regeneration cut-off valve is in the throttled open state, and the oil return back pressure is increased, which can To prevent the phenomenon of air suction and forward rush caused by the stick cylinder extending too fast; when there is positive pressure in the rodless cavity and the pressure is large, the regeneration cut-off valve is fully opened, and the throttling is no longer opened, thereby releasing the regeneration. However, when the regenerative shut-off valve is throttled open, the back pressure of the oil return is high, the pressure loss is large, and the power loss is also large.

In this regard, the present embodiment provides an arm control valve structure, which eliminates the need to provide a regeneration cut-off valve. The stick control valve structure is used to control the extension or retraction of the piston rod of the stick oil cylinder 7 of the excavator, thereby controlling the stick up or retraction. Among them, the stick is rotatably connected to the excavator boom, the cylinder body of the stick cylinder 7 is installed on the boom of the excavator, and the piston rod of the boom cylinder is rotatably connected to the stick. When the piston rod of the stick cylinder 7 extends, The stick is retracted; when the piston rod of the stick cylinder 7 retracts, the stick rises.

1 is a schematic diagram of the structure of the stick control valve structure in the embodiment of the present invention when the first valve core is located at the working position A2 and the second valve core is located at the working position B2; FIG. 2 is the stick control valve structure in the embodiment of the present invention. A schematic diagram of the structure when the first valve core is at the working position A1 and the second valve core is at the working position B1; FIG. 3 is the first valve core at the working position A1 and the second valve core at the working position A1 in the structure of the stick control valve according to the embodiment of the present invention. Schematic diagram of the structure at work position B2; FIG. 4 is a schematic view of the structure when the first valve core is located at working position A2 and the second valve core is located at working position B1 in the structure of the stick control valve in the embodiment of the present invention; FIG. 5 is the implementation of the present invention In the example, in the structure of the stick control valve, the first valve core is located at the working position A3, and the second valve core is located at the working position B3. As shown in FIGS. 1 to 5 , the stick control valve structure includes a first control valve, a second control valve and a regeneration check valve 3 .

The first control valve includes a first valve core 11. The first control valve has an input port A1, an oil return port A1, an output port A1 and an output port A2. The input port A1 is used to communicate with the first pressure source, and the oil return port A1 is used for In order to communicate with the oil tank, the output port A1 is used to communicate with the oil port A, the output port A2 is used to communicate with the oil port B, the oil port A is communicated with the rodless cavity 72 of the stick cylinder 7, and the oil port B is used to communicate with the stick cylinder 7. The rod cavity 71 is connected. Wherein, the first hydraulic source is not shown in the drawings, and may be a quantitative pump or a variable displacement pump, which provides hydraulic oil with a pressure of P1. The first spool 11 can be switched between the working position A1 and the working position A2. When the first spool 11 is in the working position A1, the input port A1 is communicated with the output port A1, and the oil return port A1 is communicated with the output port A2. When the hydraulic oil in the rod cavity 71 of the stick cylinder 7 can be returned to the oil tank through the first valve core 11, the hydraulic oil provided by the first pressure source can be provided to the rodless cylinder of the stick cylinder 7 through the first valve core 11. In the cavity 72, the piston rod of the stick cylinder 7 is extended. When the first spool 11 is at the working position A2, the input port A1, the oil return port A1, the output port A1 and the output port A2 are all closed, and there is no communication between the arm cylinder 7 and the first spool 11.

The second control valve includes a second valve core 21. The first control valve has an input port B1, a regeneration port, an oil return port B1, an output port B1 and an output port B2. The input port B1 is used to communicate with the second pressure source and return oil. The port B1 is used to communicate with the oil tank, the output port B1 is used to communicate with the oil port A, and the output port B2 is used to communicate with the oil port B, wherein the second hydraulic source is not shown in the drawings, and can be a quantitative pump or a variable Pump, which supplies hydraulic oil at pressure P2. The second spool 21 can be switched between the working position B1 and the working position B2. When the second spool 21 is at the working position B1, the input port B1 communicates with the output port B1, the regeneration port communicates with the output port B2, and the oil returns When the port B1 is disconnected, the hydraulic oil provided by the second pressure source can be supplied to the rodless cavity 72 of the stick cylinder 7 through the second spool 21, and the pressure oil in the rod cavity 71 of the stick cylinder 7 can also be Reach the regeneration port through the second spool 21; when the second spool 21 is at the working position B2, the input port B1, the regeneration port, the oil return port B1, the output port B1 and the output port B2 are all closed; at this time, the stick cylinder 7 There is no communication relationship with the second valve core 21 .

It should be noted that the first control valve in this embodiment may be a three-position multi-way valve with four or more ports, and the second control valve may be a three-position multi-port valve with five or more ports.

The regeneration check valve 3 is arranged between the regeneration port and the input port B1, and only allows the oil to flow from the regeneration port to the input port B1. When the second spool 21 is at the working position B1, if there is oil in the rod cavity 71 When the pressure is greater than the oil pressure in the rodless cavity 72, the pressure oil in the rod cavity 71 of the stick cylinder 7 can also be supplemented to the input port B1 through the second spool 21 and the regeneration check valve 3, and then supplemented to no inside the rod cavity 72 to avoid emptying. If the oil pressure in the rod chamber 71 is lower than the oil pressure in the rodless chamber 72, the regeneration check valve 3 is kept closed. Therefore, the structure of the stick control valve provided in this embodiment does not need to use the regeneration cut-off valve in the prior art, which can effectively reduce the regeneration back pressure and improve the energy efficiency. The flow rate is not affected by the strength of the second spool 21 .

In this embodiment, the valve housing of the first control valve and the valve housing of the second control valve are integrally provided.

In this embodiment, the first valve core 11 also has a working position A3, the working position A2 is located between the working position A3 and the working position A1, and the first valve core 11 can be located between the working position A1, the working position A2 and the working position A3. Switching, when the first spool 11 is in the working position A3, the input port A1 is connected to the output port A2, and the oil return port A1 is connected to the output port A1. At this time, the hydraulic oil provided by the first pressure source can pass through the first spool 11. The rod cavity 71 provided to the stick cylinder 7 and the hydraulic oil in the rodless cavity 72 of the stick cylinder 7 can be returned to the oil tank through the first valve core 11, and the piston rod of the stick cylinder 7 is retracted.

In this embodiment, the second spool 21 also has a working position B3, the working position B2 is located between the working position B3 and the working position B1, and the second spool 21 can be located between the working position B1, the working position B2 and the working position B3 Switching, when the second spool 21 is in the working position B3, the input port B1 and the output port B2 are connected, the oil return port B1 and the output port B2 are connected, and the regeneration port is disconnected. At this time, the hydraulic oil provided by the second pressure source can be supplied to the rod cavity 71 of the stick cylinder 7 through the second valve core 21, and the pressure oil in the rod cavity 71 of the stick cylinder 7 can also pass through the second valve core. 21 returns to the tank and the regeneration circuit is cut off.

In this embodiment, the first control valve further includes a first pilot hydraulic control end 12, the first pilot hydraulic control end 12 is used to drive the first spool 11 to move to the working position A1, and the first pilot hydraulic control end 12 passes through the first The oil supply device supplies pilot oil. The second control valve further includes a second pilot hydraulic control end 22, the second pilot hydraulic control end 22 is used to drive the second spool 21 to move to the working position B1, and the second pilot hydraulic control end 22 supplies the pilot through the second oil supply device Oil. Since the first pilot hydraulic control end 12 and the second pilot hydraulic control end 22 use different oil supply devices to supply the pilot oil, different combinations can be realized. For example, the first spool 11 of the first control valve is at the working position A1 and the second spool 21 of the second control valve is at the working position B1 or B2; the first spool 11 of the first control valve is at the working position A2 and the second spool 21 of the second control valve is at the working position B1 or B2; The second valve core 21 of the two control valves is located at the working position B1 or B2.

Optionally, the first control valve further includes a third pilot hydraulic control end 13, the third pilot hydraulic control end 13 is used to drive the first spool 11 to move to the working position A3, and the second control valve further includes a fourth pilot hydraulic control The end 23 and the fourth pilot hydraulic control end 23 are used to drive the second spool 21 to move to the working position B3. The third pilot hydraulic control end 13 and the fourth pilot hydraulic control end 23 both supply pilot oil through the third oil supply device. By supplying pilot oil to the third pilot hydraulic control end 13 and the fourth pilot hydraulic control end 23 at the same time by the third oil supply device, sufficient hydraulic power can be ensured when the arm is raised.

The stick control valve structure further includes a load holding valve 4, one end of the load holding valve 4 is connected to the oil port B, and the other end of the load holding valve 4 is connected to the output port A2 and the output port B2 respectively. The load holding valve 4 is an existing mature technical means, which can ensure stable pressure in the rod cavity 71 of the stick cylinder 7 .

Optionally, the stick control valve structure further includes a first on-off control valve 5 and a second on-off control valve 6, and the first on-off control valve 5 is arranged on the connecting pipeline between the first pressure source and the input port A1. , and is used to control the connection or disconnection between the first pressure source and the input port A1. The second on-off control valve 6 is disposed on the connecting pipeline between the second pressure source and the input port B1, and is used to control the connection or disconnection between the second pressure source and the input port B1.

Optionally, the stick control valve structure further includes a first electric proportional flow valve disposed on the oil supply pipeline of the first pilot hydraulic control end 12 . The stick control valve structure further includes a second electric proportional flow valve disposed on the oil supply pipeline of the second pilot hydraulic control end 22 . The signal oil pressure supplied to the first pilot hydraulic control end 12 can be adjusted through the first electronically controlled proportional flow valve, and the signal oil pressure supplied to the second pilot hydraulic control end 22 can be adjusted through the second electronically controlled proportional flow valve.

The working principle of the stick control valve structure provided in this embodiment is as follows:

1. The initial state.

As shown in Figure 1, at this time, the first pilot hydraulic control end 12 and the third pilot hydraulic control end 13 of the first control valve have no pilot oil input, the first spool 11 of the first control valve is located at the working position A2, The second pilot hydraulic control end 22 and the fourth pilot hydraulic control end 23 have no pilot oil input, the second spool 21 of the second control valve is located at the working position B2, the position of the piston rod of the stick cylinder 7 remains unchanged, and the The location remains the same.

2. Stick recovery.

The stick recovery is specifically divided into three situations: the first control valve and the second control valve work together, only the first control valve works, and only the second control valve works.

The first control valve and the second control valve cooperate. As shown in Figure 2, at this time, the first pilot hydraulic control end 12 of the first control valve has pilot oil input, the third pilot hydraulic control end 13 has no pilot oil input, and the first spool 11 is located at the working position A1; the second control valve The second pilot hydraulic control end 22 of the valve has pilot oil input, the fourth pilot hydraulic control end 23 has no pilot oil input, and the second spool 21 is located at the working position B1. At this time, the hydraulic oil provided by the first pressure source can be provided to the rodless cavity 72 of the stick cylinder 7 through the first valve core 11 , and the hydraulic oil provided by the second pressure source can be provided to the stick cylinder 7 through the second valve core 21 . The rodless cavity 72 of the stick cylinder 7 communicates with the fuel tank, and the rod cavity 71 of the stick cylinder 7 communicates with the regeneration port. When the oil pressure in the rod chamber 71 is higher than the oil pressure in the rodless chamber 72, the regeneration check valve 3 opens, and part of the hydraulic oil in the rod chamber 71 of the stick cylinder 7 returns to the oil tank through the first valve core 11 , the other part of the hydraulic oil in the rod cavity 71 of the stick cylinder 7 is supplemented to the input port B1 through the second valve core 21 and the regeneration check valve 3 , and then supplied to the rodless cavity 72 through the second valve core 21 . When the oil pressure of the rod chamber 71 is lower than the oil pressure of the rodless chamber 72, the regeneration check valve 3 is closed, and all the hydraulic oil in the rod chamber 71 of the stick cylinder 7 is returned to the oil tank through the first valve core 11. , the piston rod of the stick cylinder 7 is extended.

Only the first control valve operates. As shown in FIG. 3 , at this time, the first pilot hydraulic control end 12 of the first control valve has pilot oil input, the third pilot hydraulic control end 13 has no pilot oil input, and the first spool 11 is located at the working position A1; the second control valve The second pilot hydraulic control end 22 and the fourth pilot hydraulic control end 23 of the valve have no pilot oil input, and the second spool 21 is located at the working position B2. At this time, the hydraulic oil provided by the first pressure source can be supplied to the rodless cavity 72 of the stick cylinder 7 through the first spool 11 , and all the hydraulic oil in the rod cavity 71 of the stick cylinder 7 passes through the first spool 11 Return to the fuel tank, and the piston rod of the stick cylinder 7 extends.

Only the second control valve operates.

As shown in FIG. 4 , at this time, the first pilot hydraulic control end 12 and the third pilot hydraulic control end 13 of the first control valve have no pilot oil input, the first spool 11 is located at the working position A2, and the second control valve The second pilot hydraulic control end 22 has pilot oil input, the fourth pilot hydraulic control end 23 has no pilot oil input, and the second spool 21 is located at the working position B1. The hydraulic oil provided by the second pressure source can be supplied to the rodless cavity 72 of the stick cylinder 7 through the second spool 21. Since the hydraulic oil in the rod cavity 71 can only be discharged through the regeneration check valve 3, regardless of the rod cavity 71 Depending on the oil pressure and the oil pressure in the rodless cavity 72, the regeneration check valve 3 will be forcibly opened, and all the hydraulic oil in the rod cavity 71 of the stick cylinder 7 will pass through the second spool 21 and the regeneration check valve. 3 flows into the input port B1, and then is supplied to the rodless chamber 72 through the second valve core 21, and the piston rod of the arm cylinder 7 extends.

3. The stick rises.

As shown in Figure 5, at this time, the first pilot hydraulic control end 12 of the first control valve has no pilot oil input, the third pilot hydraulic control end 13 has pilot oil input, the first spool 11 is located at the working position A3, and the second control valve The second pilot hydraulic control end 22 of the valve has no pilot oil input, the fourth pilot hydraulic control end 23 has pilot oil input, and the second spool 21 is located at the working position B3. At this time, the hydraulic oil provided by the first pressure source can be provided to the rod cavity 71 of the stick cylinder 7 through the first valve core 11 , and the hydraulic oil provided by the second pressure source can be provided to the stick cylinder 7 through the second valve core 21 . There is a rod cavity 71, the hydraulic oil in the rodless cavity 72 of the stick cylinder 7 can be returned to the oil tank through the first valve core 11 and the second valve core 21, and the piston rod of the stick cylinder 7 is retracted.

This embodiment also provides an excavator, including the stick control valve structure in the above solution.

Obviously, the above-mentioned embodiments of the present invention are only examples for clearly illustrating the present invention, rather than limiting the embodiments of the present invention. For those of ordinary skill in the art, changes or modifications in other different forms can also be made on the basis of the above description. There is no need and cannot be exhaustive of all implementations here. Any modifications, equivalent replacements and improvements made within the spirit and principle of the present invention shall be included within the protection scope of the claims of the present invention.

Claims (10)

1. A bucket rod control valve structure, comprising:

the first control valve comprises a first valve core (11), the first control valve is provided with an input port A1, an oil return port A1, an output port A1 and an output port A2, the input port A1 is used for being communicated with a first pressure source, an oil return port A1 is used for being communicated with an oil tank, an output port A1 is used for being communicated with an oil port A, the output port A2 is used for being communicated with an oil port B, the oil port A is communicated with a rodless cavity (72) of an arm cylinder (7), the oil port B is communicated with a rod cavity (71) of the arm cylinder (7), the first valve core (11) can be switched between a working position A1 and a working position A2, when the first valve core (11) is located at the working position A1, the input port A1 is communicated with the output port A1, and the oil return port A1 is communicated with the output port A2; when the first valve spool (11) is located at the working position A2, the input port A1, the oil return port A1, the output port A1 and the output port A2 are all closed;

the second control valve comprises a second valve core (21), the first control valve is provided with an input port B1, a regeneration port, an oil return port B1, an output port B1 and an output port B2, the input port B1 is used for being communicated with a second pressure source, an oil return port B1 is used for being communicated with an oil tank, the output port B1 is used for being communicated with the oil port A, the output port B2 is used for being communicated with the oil port B, the second valve core (21) can be switched between a working position B1 and a working position B2, when the second valve core (21) is located at the working position B1, the input port B1 is communicated with the output port B1, the regeneration port is communicated with the output port B2, and the oil return port B1 is disconnected; when the second valve spool (21) is located at the working position B2, the input port B1, the regeneration port, the oil return port B1, the output port B1 and the output port B2 are all closed;

a regeneration check valve (3) disposed between the regeneration port and the input port B1 and allowing oil to flow only from the regeneration port to the input port B1.

2. The arm control valve arrangement according to claim 1, wherein the first control valve further comprises a first pilot hydraulic control port (12), the first pilot hydraulic control port (12) being adapted to drive the first spool (11) to move to the operating position a1, the first pilot hydraulic control port (12) being supplied with pilot oil by a first oil supply.

3. The arm control valve structure of claim 2, further comprising a first electro-proportional flow valve disposed on an oil supply line of the first pilot hydraulic control port (12).

4. The arm control valve arrangement according to claim 1, wherein the second control valve further comprises a second pilot hydraulic control end (22), the second pilot hydraulic control end (22) being configured to drive the second spool (21) to move to the operating position B1, the second pilot hydraulic control end (22) being supplied with pilot oil by a second oil supply.

5. The arm control valve structure of claim 4, further comprising a second electro-proportional flow valve disposed on an oil supply line of the second pilot hydraulic control port (22).

6. The arm control valve structure according to claim 1, wherein the first valve spool (11) further has a working position A3, the working position a2 is located between the working position A3 and the working position a1, the first valve spool (11) is switchable among the working position a1, the working position a2, and the working position A3, when the first valve spool (11) is located at the working position A3, the input port a1 is communicated with the output port a2, and the return port a1 is communicated with the output port a 1.

7. The arm control valve structure according to claim 6, wherein the second spool (21) further has a working position B3, the working position B2 is located between the working position B3 and the working position B1, the second spool (21) is switchable among the working position B1, the working position B2, and the working position B3, when the second spool (21) is located at the working position B3, the input port B1 and the output port B2 are communicated, the return port B1 and the output port B2 are communicated, and the regeneration port is disconnected.

8. The arm control valve arrangement according to claim 7, wherein the first control valve further comprises a third pilot hydraulic control end (13), the third pilot hydraulic control end (13) being adapted to drive the first spool (11) to move to the operating position A3, the second control valve further comprises a fourth pilot hydraulic control end (23), the fourth pilot hydraulic control end (23) being adapted to drive the second spool (21) to move to the operating position B3, the third pilot hydraulic control end (13) and the fourth pilot hydraulic control end (23) each being supplied with pilot oil by a third oil supply.

9. The arm control valve structure according to claim 1, further comprising a load holding valve (4), one end of the load holding valve (4) communicating with the oil port B, and the other end of the load holding valve (4) communicating with the output port a2 and the output port B2, respectively.

10. A shovel comprising the stick control valve arrangement of any of claims 1-9.

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