Differential circuit multi-way valve with external oil circulation function

Abstract

The application discloses a differential circuit multi-way valve with a circulating external oil supplement function, which is characterized in that a valve body is provided with a working port A, a working port B, an oil return T(A) of the working port A, an oil return T(B) of the working port B and an oil return cavity T; the oil return T(A) of the working port A is connected to the oil return cavity T; an oil supplement channel is arranged in communication at the oil return T(B) of the working port B; one end of the oil supplement channel is communicated to the oil return cavity T; a back pressure oil supplement valve for realizing bidirectional oil flow is arranged between the oil supplement channel and the oil return cavity T; the other end of the oil supplement channel is communicated to the working port A; and a one-way oil supplement valve is arranged between the oil supplement channel and the working port A; the differential circuit design of oil supplement through the oil return T(B) of the working port B converging to the working port A and the circulating external oil supplement design of the oil return cavity T converging to the working port A are realized through the cooperation of the structure of the oil supplement channel and the structure of the back pressure oil supplement valve; the oil return of the working port B is fully utilized; the oil supplement capacity is improved; and the cavitation condition is reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to a differential circuit multi-way valve with a circulating external oil supplement function. BACKGROUND

[0002] In a hydraulic machine, an oil cylinder is a hydraulic execution element that converts hydraulic energy into mechanical energy and performs linear reciprocating motion. When the piston rod of the oil cylinder is moving rapidly, insufficient oil supplement in the rod cavity of the oil cylinder causes negative pressure in the cavity. Negative pressure in the oil cylinder not only causes cavitation erosion of the piston, piston rod and cylinder cover, but also can damage the support ring on the piston, causing insufficient support of the piston and causing the oil cylinder to be pulled. To solve the problem of negative pressure caused by insufficient oil supplement during rapid movement of the piston rod of the oil cylinder, the prior art generally adds a forced oil supplement valve to the hydraulic system. The forced oil supplement valve uses pressure difference to supplement oil in the oil return cavity T to the oil cylinder through the working oil port. However, due to the long path of the oil flowing back into the working oil port, the oil supplement response is slow. SUMMARY

[0003] To solve the above technical problems, the present application provides a differential circuit multi-way valve with a circulating external oil supplement function.

[0004] The technical solution of the present application is: a differential circuit multi-way valve with a circulating external oil supplement function, a valve body is provided with a working port A, a working port B, a return oil T(A) of the working port A, a return oil T(B) of the working port B, and a return oil cavity T, the return oil T(A) of the working port A is connected to the return oil cavity T, a supplement oil channel is provided at the return oil T(B) of the working port B, one end of the supplement oil channel is connected to the return oil cavity T, a back pressure supplement oil valve that can realize bidirectional flow of oil is provided between the supplement oil channel and the return oil cavity T, the other end of the supplement oil channel is also connected to the working port A, a one-way supplement oil valve is provided between the supplement oil channel and the working port A; the back pressure supplement oil valve includes a back pressure supplement oil valve hole provided in the valve body, the inside of the back pressure supplement oil valve hole is connected between the supplement oil channel and the return oil cavity T, an outer return oil valve core and an inner supplement oil valve core are coaxially sleeved in the back pressure supplement oil valve hole, the inner supplement oil valve core is axially limited and fitted in the outer return oil valve core, the inner end of the inner supplement oil valve core is sealed from inside to outside at the inner end of the outer return oil valve core, the outer return oil valve core is axially limited and fitted in the back pressure supplement oil valve hole, the inner end of the outer return oil valve core is sealed from outside to inside on the inner side wall of the back pressure supplement oil valve hole, and the inner end of the outer return oil valve core is also provided with a supplement oil through hole.

[0005] As a preferred technical scheme, the outer return oil valve core is slidably installed in the back pressure oil supplement valve hole, and an outer valve core reset member is arranged between the outer end of the outer return oil valve core and the valve body.

[0006] As a preferred technical scheme, the outer valve core reset member comprises a back pressure oil supplement valve seat installed on the valve body, and an outer valve core spring is arranged between the outer end of the outer return oil valve core and the back pressure oil supplement valve seat.

[0007] As a preferred technical scheme, the inner end of the outer return oil valve core is provided with a valve core flow guide cavity in communication with the oil supplement channel, the oil supplement through hole is in communication with the oil circuit between the return oil cavity T and the valve core flow guide cavity, an inner valve core reset member is arranged between the outer end of the inner oil supplement valve core and the outer return oil valve core, and the inner end of the inner oil supplement valve core abuts against the inner end face of the outer return oil valve core under the action of the inner valve core reset member to externally close the oil circuit between the oil supplement channel and the valve core flow guide cavity.

[0008] As a preferred technical scheme, the inner valve core reset member comprises an inner valve core outer sleeve installed outside the inner oil supplement valve core, and an inner valve core spring is arranged between the inner valve core outer sleeve and the outer return oil valve core.

[0009] Due to the above technical scheme, when the flow at the working port A is sufficient, the one-way oil supplement valve is closed, the oil liquid of the return oil T(B) of the working port B accumulates pressure in the oil supplement channel, pushes the back pressure oil supplement valve to open, and the oil liquid in the oil supplement channel flows back to the return oil tank T; when the flow at the working port A is insufficient and negative pressure occurs, the one-way oil supplement valve opens, the back pressure oil supplement valve closes, the oil liquid of the return oil T(B) of the working port B enters the working port A through the oil supplement channel and the one-way oil supplement valve, and the return oil T(B) of the working port B supplements oil; when the return oil T(B) of the working port B does not meet the flow demand of the working port A and there is still negative pressure at the working port A, the back pressure oil supplement valve opens, the oil liquid in the return oil tank T enters the working port A through the back pressure oil supplement valve, the oil supplement channel and the one-way oil supplement valve, and the return oil tank T further supplements oil.

[0010] The beneficial effects of the present application are realized by the cooperation of the structure of the oil supplement channel and the structure of the back pressure oil supplement valve, first, the differential circuit design of the oil return T(B) of the working port B converging to the working port A for oil supplement and the circulating external oil supplement design of the oil return cavity T converging to the working port A are realized. When the oil return T(B) of the working port B just meets the oil supplement demand, the oil supplement of the oil return cavity T does not need to be started. When the oil return T(B) of the working port B does not meet the oil supplement demand, the oil in the oil return cavity T is used for oil supplement. When the oil return T(B) of the working port B exceeds the oil supplement demand, the back pressure function of the back pressure oil supplement valve is opened to return to the oil return cavity T. In this way, the oil return of the working port B can be fully utilized, the oil supplement response is faster, the oil supplement capacity is improved, and the conditions for cavitation erosion are reduced. BRIEF DESCRIPTION OF DRAWINGS

[0011] The following drawings are only intended to illustrate and explain the present application and do not limit the scope of the present application. Among them:

[0012] Figure 1 is a schematic diagram of an embodiment of the present application;

[0013] Figure 2 is a hydraulic principle diagram of an embodiment of the present application;

[0014] Figure 3 is a principle of state one of an embodiment of the present application Figure 1 ;

[0015] Figure 4 is a principle of state one of an embodiment of the present application Figure 2 ;

[0016] Figure 5 is a principle diagram of the back pressure oil supplement valve of state one of an embodiment of the present application;

[0017] Figure 6 is a principle of state two of an embodiment of the present application Figure 1 ;

[0018] Figure 7 is a principle of state two of an embodiment of the present application Figure 2 ;

[0019] Figure 8 is a principle of state three of an embodiment of the present application Figure 1 ;

[0020] Figure 9 is a principle of state three of an embodiment of the present application Figure 2 ;

[0021] Figure 10 is a principle diagram of the back pressure oil supplement valve of state three of an embodiment of the present application;

[0022] In the figure: 1-valve body; 2-oil return T(A) of working port A; 3-oil return T(B) of working port B; 4-oil supplement channel; 5-back pressure oil supplement valve; 51-valve hole of back pressure oil supplement valve; 52-outer oil return valve core; 53-inner oil supplement valve core; 54-oil supplement through hole; 55-valve seat of back pressure oil supplement valve; 56-outer valve core spring; 57-valve core flow guide cavity; 58-inner valve core sleeve; 59-inner valve core spring; 6-one-way oil supplement valve. DETAILED DESCRIPTION

[0023] The application will be further described below in conjunction with the drawings and examples. In the following detailed description of the application, only certain exemplary embodiments of the application are described through illustration only. It should be apparent that the application can be carried out in a variety of ways, and that the exemplified embodiments are only exemplary. Variations of these embodiments can become apparent to those of ordinary skill in the art upon reading the foregoing description. Accordingly, inventive embodiments encompass all modifications implied by these equivalents and same are intended to be encompassed by the claims.

[0024] In the description of the application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the application and simplifying the description, and therefore cannot be understood as indicating or implying that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the application. In addition, the terms "first", "second", "third" are only for the purpose of description, and cannot be understood as indicating or implying relative importance.

[0025] As Figures 1 to 4As shown, the differential circuit multi-way valve with circulating external oil supplement function comprises a valve body 1, wherein the valve body 1 is provided with a working port A, a working port B, a return oil port T(A) 2 of the working port A, a return oil port T(B) 3 of the working port B, the return oil port T(A) 2 of the working port A is connected to a return oil chamber T, the return oil port T(B) 3 is provided with an oil supplement channel 4, one end of the oil supplement channel 4 is connected to the return oil chamber T, a back pressure oil supplement valve 5 for realizing bidirectional flow of oil is arranged between the oil supplement channel 4 and the return oil chamber T, the other end of the oil supplement channel 4 is also connected to the working port A, and a one-way oil supplement valve 6 is arranged between the oil supplement channel 4 and the working port A. The return oil port T(A) 2 of the working port A is directly connected to the return oil chamber T without obstruction, which can be called a large return oil channel, the other end of the oil supplement channel 4 is connected to the large return oil channel, which belongs to indirect connection to the return oil chamber T, and a back pressure oil supplement valve 5 is arranged between the oil supplement channel 4 and the large return oil channel for oil passage control. When the flow at the working port A is sufficient, the one-way oil supplement valve 6 is closed, the oil in the return oil port T(B) 3 of the working port B accumulates pressure in the oil supplement channel 4, pushes the back pressure oil supplement valve 5 to open, and the oil in the oil supplement channel 4 flows back to the return oil chamber T; when the flow at the working port A is insufficient and negative pressure occurs, the one-way oil supplement valve 6 is opened, the back pressure oil supplement valve 5 is closed, the oil in the return oil port T(B) 3 of the working port B enters the working port A through the oil supplement channel 4 and the one-way oil supplement valve 6, and is supplemented through the return oil port T(B) 3 of the working port B; when the oil supplement of the return oil port T(B) 3 of the working port B cannot meet the flow demand of the working port A and there is still negative pressure at the working port A, the back pressure oil supplement valve 5 is opened, and the oil in the return oil chamber T enters the working port A through the back pressure oil supplement valve 5, the oil supplement channel 4 and the one-way oil supplement valve 6, and is further supplemented through the return oil chamber T.

[0026] The oil supplement channel 4 has the following functions: 1. The oil supplement channel 4 directly connects the working port A and the return oil port T(B) of the working port B, and is used for guiding the oil in the return oil port T(B) 3 of the working port B to the working port A, so as to supplement the oil by using the return oil port T(B) 3 of the working port B; 2. The oil supplement channel 4 is also connected to the return oil chamber T, and when the return oil amount of the return oil port T(B) 3 of the working port B cannot meet the oil supplement demand of the working port A, the oil in the return oil chamber T enters the working port A through the oil supplement channel 4 to supplement the oil. The back pressure oil supplement valve 5 is arranged between the oil supplement channel 4 and the return oil chamber T, realizes the forward and reverse passing of the oil, the oil in the oil supplement channel 4 can enter the return oil chamber T, and the oil in the return oil chamber T can also enter the oil supplement channel 4, and the specific flow direction is determined according to the pressure difference between the return oil chamber T and the oil supplement channel 4.

[0027] Referring to Figure 5, the back pressure oil supplement valve 5 comprises a back pressure oil supplement valve hole 51 arranged in the valve body 1, an inner side of the back pressure oil supplement valve hole 51 is communicated between the oil supplement channel 4 and the oil return cavity T, an outer oil return valve core 52 and an inner oil supplement valve core 53 are coaxially sleeved in the back pressure oil supplement valve hole 51, the inner oil supplement valve core 53 is axially limited and matched in the outer oil return valve core 52, an inner end head part (the right end in Figure 5 ) of the inner oil supplement valve core 53 is sealed from inside to outside on an inner end of the outer oil return valve core 52, the outer oil return valve core 52 is axially limited and matched in the back pressure oil supplement valve hole 51, an inner end head part (the right end in Figure 5 ) of the outer oil return valve core 52 is sealed from outside to inside on an inner side wall of the back pressure oil supplement valve hole 51, and the outer oil return valve core 52 is further provided with an oil supplement through hole 54 on an inner end peripheral side.

[0028] The outer oil return valve core 52 is slidably installed in the back pressure oil supplement valve hole 51, an outer end of the outer oil return valve core 52 and the valve body 1 are provided with an outer valve core reset member, the outer valve core reset member comprises a back pressure oil supplement valve seat 55 installed on the valve body 1, an outer end (the left end in Figure 5 ) of the outer oil return valve core 52 and the back pressure oil supplement valve seat 55 are provided with an outer valve core spring 56, and an inner end head part (the right end in Figure 5 ) of the outer oil return valve core 52 abuts against an inner side end face of the back pressure oil supplement valve hole 51 to close an oil path between the oil supplement channel 4 and the oil return cavity T under the action of the outer valve core reset member (a normally closed state, that is, the right position in Figure 5 ), and when the outer oil return valve core 52 moves to the left by overcoming the pressure of the outer valve core spring 56, the oil path between the oil supplement channel 4 and the oil return cavity T is opened.

[0029] The inner end of the outer oil return valve core 52 is provided with a valve core flow guide cavity 57 communicated with the oil supplement channel 4, an outer peripheral surface of the inner oil supplement valve core 53 is slidably sealed with an outer end (the left end in Figure 5 ) of the valve core flow guide cavity 57, and an inner end (the right end in Figure 5 ) of the valve core flow guide cavity 57 is open for communication with the oil supplement channel 4, the oil supplement through hole 54 communicates an oil path between the oil return cavity T and the valve core flow guide cavity 57, and an outer end (the left end in Figure 5 ) of the inner oil supplement valve core 53 and the outer oil return valve core 52 are provided with an inner valve core reset member, the inner valve core reset member comprises an inner valve core outer sleeve 58 installed outside the inner oil supplement valve core 53, the inner valve core outer sleeve 58 and the outer oil return valve core 52 are provided with an inner valve core spring 59, and an inner end (the left end in Figure 5the outer oil return valve core 52 (the right end in the figure) is closed against the inner end face of the outer oil return valve core 52 under the action of the inner valve core reset member, closing the oil passage between the oil supplement passage 4 and the valve core flow guide cavity 57 (normally closed state, i.e. Figure 5 When the inner oil supplement valve core 53 moves to the right against the pressure of the inner valve core spring 59, the oil passage between the oil supplement passage 4 and the oil return cavity T is opened through the oil supplement passage through hole 54 and the valve core flow guide cavity 57.

[0030] The working principle of the embodiment is as follows:

[0031] State one: when the flow at the working port A is sufficient, the oil in the oil return T(B) 3 of the working port B enters the oil supplement passage 4, at this time the oil pressure in the oil supplement passage 4 is obviously smaller than the oil pressure at the working port A, the one-way oil supplement valve 6 is closed, and the accumulated pressure of the oil in the oil supplement passage 4 gradually rises. When the pressure in the oil passage is greater than the elastic force of the outer valve core spring 56, the outer oil return valve core 52 is pushed to move to the left, so that the oil passage between the oil supplement passage 4 and the oil return cavity T is opened. At this time, the oil in the oil supplement passage 4 flows back to the oil return cavity T, and the oil flow route is shown in Figure 3 , Figure 4 and Figure 5 ;

[0032] State two: when the flow at the working port A is insufficient and a negative pressure occurs, the oil in the oil return T(B) 3 of the working port B enters the oil supplement passage 4, and a larger pressure difference at the working port A causes the valve core of the one-way oil supplement valve 6 to move to the left to open. At this time, the oil in the oil supplement passage 4 flows back and enters the working port A through the one-way oil supplement valve 6, and is supplemented through the oil return T(B) 3 of the working port B. In this process, since the oil in the oil supplement passage 4 first enters the working port A, the outer oil return valve core 52 will not be pushed open. At this time, the oil return T(B) 3 of the working port B will first enter the working port A for oil supplement, and since there is oil in the oil supplement passage 4, the pressure is greater than that in the oil return cavity T, the inner oil supplement valve core 53 is closed, i.e. the back pressure oil supplement valve 5 is closed in both forward and reverse directions, and the oil flow route is shown in Figure 6 and Figure 7 ;

[0033] State three: when the oil return T(B) 3 of the working port B cannot meet the flow demand of the working port A, and there is still negative pressure at the working port A, the inner oil supplement valve core 53 moves right under the action of the negative pressure at the working port A and overcomes the elastic force of the inner valve core spring 59, and the oil channel between the inner oil supplement valve core 53 and the outer oil return valve core 52 is opened, at this time, the oil in the oil return cavity T enters the oil supplement channel 4 through the oil supplement through hole 54 and the valve core flow guide cavity 57, and then enters the working port A through the one-way oil supplement valve 6, and the oil supplement is performed through the oil return cavity T, and the oil flow route is shown in Figure 8 、 Figure 9 and Figure 10 .

[0034] The present application realizes the oil supplement through the oil return T(B) 3 of the working port B first, and when the oil return T(B) 3 of the working port B can meet the oil supplement demand, the oil supplement of the oil return cavity T is not needed to be started, and when the oil return T(B) 3 of the working port B cannot meet the oil supplement demand, the oil supplement is performed through the oil in the oil return cavity T, and this oil supplement mode can fully utilize the oil return of the working port B and has a faster oil supplement response.

[0035] The working port A is supplied with oil according to the action of the main valve core, in the embodiment, referring to Figure 2 When the valve body has two main valve cores, the first main valve core corresponds to the working port A1 and the working port B1 respectively, and the second main valve core corresponds to the working port A2 and the working port B2, wherein the oil return channel of the working port B1 and the oil return channel of the working port B2 are connected in parallel at one end of the oil supplement channel, and the working port A1 and the working port A2 are connected in parallel at the other end of the oil supplement channel. When the first main valve core is in action and the second main valve core is not in action, and the flow at the working port A1 meets the requirement, the oil in the oil return channel of the working port B1 enters the oil supplement channel 4, at this time, the oil pressure in the oil supplement channel 4 is obviously smaller than the oil pressure at the working port A1, so the one-way oil supplement valve at the working port A1 is closed, and the accumulated pressure of the oil in the oil supplement channel 4 gradually rises until the outer oil return valve core 52 is pushed to move left, so that the oil channel between the oil supplement channel 4 and the oil return cavity T is opened, at this time, the oil in the oil supplement channel 4 flows back to the oil return cavity T, and the state of the working port A2 is not affected.

[0036] The above shows and describes the basic principles, main features and advantages of the present application. Those skilled in the art should understand that the present application is not limited to the above-mentioned embodiments, and the above-mentioned embodiments and descriptions in the specification are only to illustrate the principles of the present application. Without departing from the spirit and scope of the present application, various changes and improvements can be made to the present application, and these changes and improvements all fall within the scope of the claimed present application. The scope of protection of the present application is defined by the appended claims and their equivalents.

Claims

1. A differential circuit multi-way valve with a circulating external oil supplement function, a valve body is provided with a working port A, a working port B, a working port A oil return T(A), a working port B oil return T(B), and an oil return cavity T, the working port A oil return T(A) is connected to the oil return cavity T, characterized in that: The oil return T(B) of the working port B is communicated with an oil supplement channel, one end of the oil supplement channel is communicated with the oil return cavity T, a back pressure oil supplement valve enabling bidirectional oil flow is arranged between the oil supplement channel and the oil return cavity T, the other end of the oil supplement channel is also communicated with the working port A, and a one-way oil supplement valve is arranged between the oil supplement channel and the working port A; the back pressure oil supplement valve comprises a back pressure oil supplement valve hole arranged in the valve body, an inner oil supplement valve core and an outer oil return valve core are coaxially sleeved in the back pressure oil supplement valve hole, the inner oil supplement valve core is axially limited and matched in the outer oil return valve core, the inner end head of the inner oil supplement valve core is sealed from inside to outside on the inner end of the outer oil return valve core, the outer oil return valve core is axially limited and matched in the back pressure oil supplement valve hole, the inner end head of the outer oil return valve core is sealed from outside to inside on the inner side wall of the back pressure oil supplement valve hole, and the inner end side of the outer oil return valve core is also provided with an oil supplement through hole.

2. The differential circuit multi-way valve with a circulating external oil supplement function according to claim 1, characterized in that: The outer oil return valve core is slidably installed in the back pressure oil supplement valve hole, an outer valve core reset member is arranged between the outer end of the outer oil return valve core and the valve body, and the inner end head of the outer oil return valve core is abutted against the inner side end face of the back pressure oil supplement valve hole to close the oil path between the oil supplement channel and the oil return cavity T under the action of the outer valve core reset member.

3. The differential circuit multi-way valve with a circulating external oil supplement function according to claim 2, characterized in that: The outer valve core reset member comprises a back pressure oil supplement valve seat installed on the valve body, and an outer valve core spring is arranged between the outer end of the outer oil return valve core and the back pressure oil supplement valve seat.

4. The differential circuit multi-way valve with a circulating external oil supplement function according to claim 1, characterized in that: The inner end of the outer oil return valve core is provided with a valve core flow guide cavity communicated with the oil supplement channel, the oil supplement through hole is communicated with the oil path between the oil return cavity T and the valve core flow guide cavity, an inner valve core reset member is arranged between the outer end of the inner oil supplement valve core and the outer oil return valve core, and the inner end of the inner oil supplement valve core is abutted against the inner end face of the outer oil return valve core to externally close the oil path between the oil supplement channel and the valve core flow guide cavity under the action of the inner valve core reset member.

5. The differential circuit multi-way valve with a circulating external oil supplement function according to claim 4, characterized in that: The inner valve core reset member comprises an inner valve core outer sleeve installed outside the inner oil supplement valve core, and an inner valve core spring is arranged between the inner valve core outer sleeve and the outer oil return valve core.

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