Synchronous oil cylinder hydraulic system

Abstract

The utility model provides a synchronous oil cylinder hydraulic system which comprises a pressure oil way, an oil return way, a multi-way valve, a first oil cylinder and a second oil cylinder, the pressure oil way is connected with a pressure oil port of the multi-way valve, and the oil return way is connected with an oil return port of the multi-way valve; the multi-way valve is provided with a first working interface and a second working interface, the first working interface of the multi-way valve is connected with a cylinder body side interface of the first oil cylinder, a piston rod side interface of the first oil cylinder is connected with a cylinder body side interface of the second oil cylinder, and a piston rod side interface of the second oil cylinder is connected with the second working interface of the multi-way valve. According to the utility model, the multi-way valve, the first oil cylinder and the second oil cylinder form a series loop, so that the synchronization and the same-stroke control of the first oil cylinder and the second oil cylinder are realized; the flow grabbing phenomenon of double oil cylinders is avoided, and the reliability is good; and the multi-way valve controls the output direction of the hydraulic oil, so that the first oil cylinder and the second oil cylinder can synchronously extend and retract, and bidirectional control is realized.

Description

Technical Field

[0001] The utility model relates to the technical field of hydraulic systems for agricultural machinery, in particular to a synchronous oil cylinder hydraulic system. Background Art

[0002] As tractors are equipped with more and more tools, the heads of tractors also have a wider range of uses. Among the tools configured for small horsepower models, some working tools need to be controlled synchronously and with the same stroke. However, in the current dual-cylinder hydraulic system, synchronous movement can only be achieved if both cylinders are used to drive the same tool. For example, in the grain box lifting system of the harvester, the cylinders on both sides of the grain box are used to drive the same grain box, and the load capacity of a single cylinder is less than the weight of the grain box, so that the two cylinders can automatically divide the pressure and move synchronously. If the two cylinders are used to drive two tools respectively, there will be a flow rush phenomenon, and the hydraulic oil will preferentially flow to the tool with less resistance, and synchronous and same-stroke control cannot be reliably achieved. At the same time, the return of the above-mentioned dual-cylinder hydraulic system relies on the self-gravity of the tool, and two-way control cannot be achieved. Utility Model Content

[0003] The technical problem to be solved by the utility model is: how to reliably perform synchronization and bidirectional control of the same stroke on a working machine.

[0004] The technical solution of the utility model to solve the above technical problems is as follows:

[0005] The utility model provides a synchronous oil cylinder hydraulic system, comprising a pressure oil circuit, an oil return circuit, a multi-way valve, a first oil cylinder, and a second oil cylinder, wherein the pressure oil circuit is connected to the pressure oil port of the multi-way valve, and the oil return circuit is connected to the oil return port of the multi-way valve; the multi-way valve is provided with a first working interface and a second working interface, the first working interface of the multi-way valve is connected to the cylinder body side interface of the first oil cylinder, the piston rod side interface of the first oil cylinder is connected to the cylinder body side interface of the second oil cylinder, and the piston rod side interface of the second oil cylinder is connected to the second working interface of the multi-way valve.

[0006] The beneficial effects of the utility model are:

[0007] By adopting the utility model, a series circuit is formed by the multi-way valve, the first oil cylinder and the second oil cylinder, so that the synchronization and the same stroke control of the first oil cylinder and the second oil cylinder are realized; the phenomenon of double oil cylinders competing for flow is avoided, and the reliability is good; the multi-way valve controls the output direction of the hydraulic oil, so that the first oil cylinder and the second oil cylinder can be extended and retracted synchronously, and two-way control is realized.

[0008] On the basis of the above technical solution, the present invention can also be improved as follows.

[0009] Furthermore, a first compensation interface is provided on the first oil cylinder, and the first compensation interface and the piston rod side interface of the first oil cylinder are arranged at intervals along the axial direction of the first oil cylinder; the first compensation interface is provided with a first one-way valve, and the outlet of the first one-way valve is connected to the cylinder body side of the second oil cylinder.

[0010] When the first cylinder is fully extended, the cylinder body side of the first cylinder is connected to the first one-way valve. At this time, if the second cylinder has not been fully extended, the hydraulic oil on the cylinder body side of the first cylinder can enter the cylinder body side of the second cylinder through the first one-way valve, ensuring that the strokes of the two cylinders are consistent.

[0011] Furthermore, the distance between the first compensation interface and the piston rod side interface of the first oil cylinder is the piston length of the first oil cylinder.

[0012] When the first oil cylinder is fully extended, the piston of the first oil cylinder just passes through the first compensation interface, so that the first compensation interface just connects to the cylinder body side of the first oil cylinder, ensuring that the first oil cylinder can be fully extended with good reliability.

[0013] Furthermore, the second oil cylinder is also provided with a second compensation interface, and the second compensation interface and the cylinder body side interface of the second oil cylinder are arranged at intervals along the axial direction of the second oil cylinder; the second compensation interface is provided with a second one-way valve, and the outlet of the second one-way valve is connected to the piston rod side of the first oil cylinder.

[0014] When the second cylinder is fully retracted, the piston rod side of the second cylinder is connected to the second one-way valve. At this time, if the first cylinder has not been fully retracted, the hydraulic oil on the piston rod side of the second cylinder can enter the piston rod side of the first cylinder through the second one-way valve, ensuring the consistency of the strokes of the two cylinders.

[0015] Furthermore, the distance between the second compensation interface and the cylinder body side interface of the second oil cylinder is the piston length of the second oil cylinder.

[0016] When the second oil cylinder is fully retracted, the piston of the second oil cylinder just passes through the second compensation interface, so that the second compensation interface just connects to the piston rod side of the second oil cylinder, ensuring that the second oil cylinder can be fully retracted with good reliability.

[0017] Furthermore, a first hydraulically controlled one-way valve is provided on the oil circuit from the first working interface of the multi-way valve to the first oil cylinder, and the control oil port of the first hydraulically controlled one-way valve is connected to the second working interface of the multi-way valve; a second hydraulically controlled one-way valve is provided on the oil circuit from the second working interface of the multi-way valve to the second oil cylinder, and the control oil port of the second hydraulically controlled one-way valve is connected to the first working interface of the multi-way valve.

[0018] The first hydraulically controlled one-way valve and the second hydraulically controlled one-way valve stroke bidirectional hydraulic lock, when the first working interface and the second working interface of the multi-way valve do not deliver oil, it is convenient to close the two oil cylinders so that the two oil cylinders stay in the same extension position at the same time, thereby realizing the load holding function.

[0019] Furthermore, it also includes a safety valve, the inlet of the safety valve is connected to the pressure oil circuit, and the outlet of the safety valve is connected to the return oil circuit.

[0020] When the oil pressure in the pressure oil circuit is too high, part of the oil is released to the return oil circuit through the safety valve, which improves the safety of the hydraulic system.

[0021] Furthermore, it also includes a hydraulic pump and an oil tank, the inlet of the hydraulic pump and the oil return line are respectively connected to the oil tank, and the outlet of the hydraulic pump is connected to the pressure oil circuit.

[0022] It is convenient to provide a pressure oil source and the hydraulic oil can be recycled at the same time, which is economical.

[0023] Furthermore, an oil filter is provided on the oil line from the oil tank to the hydraulic pump.

[0024] It is convenient to filter the hydraulic oil and improve the cleanliness of the hydraulic oil entering the hydraulic system.

[0025] Furthermore, the oil filter is also connected in parallel with a third one-way valve, and the third one-way valve can allow the oil to flow from the oil tank to the hydraulic pump in one direction.

[0026] When the flow rate of the hydraulic pump is large or the resistance of the oil filter increases, oil can be sucked through the third one-way valve to prevent the hydraulic pump from sucking air and play a protective role. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a structural schematic diagram of the utility model.

[0028] In the accompanying drawings, the technical features represented by the reference numerals are as follows:

[0029] 1-pressure oil circuit; 2-return oil circuit; 3-multi-way valve; 4-first oil cylinder; 5-second oil cylinder; 6-first working interface; 7-second working interface; 8-first one-way valve; 9-second one-way valve; 10-first hydraulically controlled one-way valve; 11-second hydraulically controlled one-way valve; 12-safety valve; 13-hydraulic pump; 14-oil tank; 15-oil filter; 16-third one-way valve. DETAILED DESCRIPTION

[0030] The principles and features of the present invention are described below in conjunction with the accompanying drawings. The examples given are only used to explain the present invention and are not used to limit the scope of the present invention.

[0031] This utility model refers to Figure 1 .

[0032] The utility model provides a synchronous oil cylinder hydraulic system, comprising a pressure oil circuit 1, an oil return circuit 2, a multi-way valve 3, a first oil cylinder 4, and a second oil cylinder 5. The pressure oil circuit 1 is connected to the pressure oil port of the multi-way valve 3, and the oil return circuit 2 is connected to the oil return port of the multi-way valve 3; the multi-way valve 3 is provided with a first working interface 6 and a second working interface 7, the first working interface 6 of the multi-way valve 3 is connected to the cylinder body side interface of the first oil cylinder 4, the piston rod side interface of the first oil cylinder 4 is connected to the cylinder body side interface of the second oil cylinder 5, and the piston rod side interface of the second oil cylinder 5 is connected to the second working interface 7 of the multi-way valve 3.

[0033] principle:

[0034] During installation, the pressure oil circuit 1 is used to connect the hydraulic oil source to provide hydraulic oil for the multi-way valve 3; the return oil circuit 2 is used for hydraulic oil return. The first oil cylinder 4 and the second oil cylinder 5 can be used to drive the lifting of the machine. A two-way oil cylinder is used. The two-way oil cylinder has two interfaces on the cylinder body side and the piston rod side. Oil supply on the cylinder body side can extend the oil cylinder, and oil supply on the piston rod side can retract the oil cylinder. This is the existing technology.

[0035] When working, the multi-way valve 3 can be switched to the output of the first working interface 6 and the output of the second working interface 7. When the multi-way valve 3 is switched to the output of the first working interface 6, the first working interface 6 supplies oil to the cylinder body side of the first oil cylinder 4, and the first oil cylinder 4 extends; at the same time, the hydraulic oil on the piston rod side of the first oil cylinder 4 is output to the cylinder body side of the second oil cylinder 5, and the second oil cylinder 5 extends; the hydraulic oil on the piston rod side of the second oil cylinder 5 enters the multi-way valve 3 through the second working interface 7 of the multi-way valve 3 and flows back to the oil return line 2. This ensures that the first oil cylinder 4 and the second oil cylinder 5 extend synchronously and have the same stroke. When the multi-way valve 3 switches to the output of the second working interface 7, the second working interface 7 supplies oil to the piston rod side of the second oil cylinder 5, and the second oil cylinder 5 retracts; at the same time, the hydraulic oil on the cylinder body side of the second oil cylinder 5 is output to the piston rod side of the first oil cylinder 4, and the first oil cylinder 4 retracts; the hydraulic oil on the cylinder body side of the first oil cylinder 4 enters the multi-way valve 3 through the first working interface 6 of the multi-way valve 3 and flows back to the oil return line 2. This ensures that the first oil cylinder 4 and the second oil cylinder 5 retract synchronously and have the same stroke.

[0036] By adopting the utility model, a series circuit is formed by the multi-way valve 3, the first oil cylinder 4 and the second oil cylinder 5, so that the synchronization and the same stroke control of the first oil cylinder 4 and the second oil cylinder 5 are realized; the double cylinder flow grabbing phenomenon is avoided, and the reliability is good; the multi-way valve 3 controls the output direction of the hydraulic oil, so that the first oil cylinder 4 and the second oil cylinder 5 can be extended and retracted synchronously, realizing two-way control.

[0037] Furthermore, a first compensation interface is provided on the first oil cylinder 4, and the first compensation interface and the piston rod side interface of the first oil cylinder 4 are arranged at intervals along the axial direction of the first oil cylinder 4; the first compensation interface is provided with a first one-way valve 8, and the outlet of the first one-way valve 8 is connected to the cylinder body side of the second oil cylinder 5.

[0038] Note: The outlet of the first check valve 8 can be used as a branch to connect to the cylinder body side interface of the second cylinder 5. In actual products, there are theoretical errors and different leakage amounts of the cylinders. This may cause the two cylinders to retract / extend synchronously, but there is an error in the actual stroke, for example, the first cylinder 4 is fully extended, but the second cylinder 5 is not fully extended.

[0039] When the first cylinder 4 is fully extended, the cylinder body side of the first cylinder 4 is connected to the first one-way valve 8. At this time, if the second cylinder 5 has not been fully extended, the hydraulic oil on the cylinder body side of the first cylinder 4 can enter the cylinder body side of the second cylinder 5 through the first one-way valve 8, ensuring that the strokes of the two cylinders are consistent.

[0040] Furthermore, the distance between the first compensation interface and the piston rod side interface of the first oil cylinder 4 is the piston length of the first oil cylinder 4 .

[0041] When the first oil cylinder 4 is fully extended, the piston of the first oil cylinder 4 just passes through the first compensation interface, so that the first compensation interface just connects to the cylinder body side of the first oil cylinder 4, ensuring that the first oil cylinder 4 can be fully extended with good reliability.

[0042] Furthermore, a second compensation interface is provided on the second oil cylinder 5, and the second compensation interface and the cylinder body side interface of the second oil cylinder 5 are arranged at intervals along the axial direction of the second oil cylinder 5; a second one-way valve 9 is provided on the second compensation interface, and the outlet of the second one-way valve 9 is connected to the piston rod side of the first oil cylinder 4.

[0043] When the second cylinder 5 is fully retracted, the piston rod side of the second cylinder 5 is connected to the second one-way valve 9. At this time, if the first cylinder 4 has not been fully retracted, the hydraulic oil on the piston rod side of the second cylinder 5 can enter the piston rod side of the first cylinder 4 through the second one-way valve 9, ensuring that the strokes of the two cylinders are consistent.

[0044] Furthermore, the distance between the second compensation interface and the cylinder body side interface of the second oil cylinder 5 is the piston length of the second oil cylinder 5 .

[0045] When the second oil cylinder 5 is fully retracted, the piston of the second oil cylinder 5 just passes through the second compensation interface, so that the second compensation interface just connects to the piston rod side of the second oil cylinder 5, ensuring that the second oil cylinder 5 can be fully retracted, with good reliability.

[0046] Furthermore, a first hydraulically controlled one-way valve 10 is provided on the oil circuit from the first working interface 6 of the multi-way valve 3 to the first oil cylinder 4, and the control oil port of the first hydraulically controlled one-way valve 10 is connected to the second working interface 7 of the multi-way valve 3; a second hydraulically controlled one-way valve 11 is provided on the oil circuit from the second working interface 7 of the multi-way valve 3 to the second oil cylinder 5, and the control oil port of the second hydraulically controlled one-way valve 11 is connected to the first working interface 6 of the multi-way valve 3.

[0047] The first hydraulically controlled one-way valve 10 and the second hydraulically controlled one-way valve 11 form a two-way hydraulic lock. When the first working interface 6 and the second working interface 7 of the multi-way valve 3 do not deliver oil, it is convenient to close the two cylinders so that the two cylinders stay in the same extension position at the same time, thereby realizing the load holding function.

[0048] Furthermore, it also includes a safety valve 12 , the inlet of the safety valve 12 is connected to the pressure oil circuit 1 , and the outlet of the safety valve 12 is connected to the return oil circuit 2 .

[0049] When the oil pressure in the pressure oil circuit 1 is too high, part of the oil is released to the return oil circuit 2 through the safety valve 12, thereby improving the safety of the hydraulic system.

[0050] Furthermore, it also includes a hydraulic pump 13 and an oil tank 14 , the inlet of the hydraulic pump 13 and the oil return line 2 are connected to the oil tank 14 respectively, and the outlet of the hydraulic pump 13 is connected to the pressure oil circuit 1 .

[0051] It is convenient to provide a pressure oil source and the hydraulic oil can be recycled at the same time, which is economical.

[0052] Furthermore, an oil filter 15 is provided on the oil line from the oil tank 14 to the hydraulic pump 13 .

[0053] It is convenient to filter the hydraulic oil and improve the cleanliness of the hydraulic oil entering the hydraulic system.

[0054] Furthermore, the oil filter 15 is also connected in parallel with a third one-way valve 16 , and the third one-way valve 16 can allow oil to flow from the oil tank 14 to the hydraulic pump 13 in one direction.

[0055] When the flow rate of the hydraulic pump 13 is large or the resistance of the oil filter 15 increases, oil can be sucked through the third one-way valve 16 to prevent the hydraulic pump 13 from sucking empty, thus playing a protective role.

[0056] Preferably, a plurality of multi-way valves 3 can be provided, and the number of first oil cylinders 4 and the number of second oil cylinders 5 are the same as the number of multi-way valves 3. This facilitates simultaneous control of multiple groups of double oil cylinders to move synchronously with the same stroke.

[0057] In the description of the present invention, it should be understood that if there are descriptive terms indicating orientation, direction or positional relationship, such as: "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., the orientation or positional relationship indicated in this specification is based on the orientation or positional relationship shown in the accompanying drawings, which is only for the convenience of understanding the present invention and simplifying the description, and does not indicate or imply that the referred part, element or whole must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0058] In addition, if there are order description terms, such as "first", "second", etc., their purpose in this specification is to facilitate understanding or simplify description. For example, in order to distinguish multiple technical features of the same type or function, but they have to be mentioned separately, this specification may use prefix or suffix order description terms to distinguish them. Therefore, it cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present utility model, the meaning of "multiple" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0059] In the present utility model, if the terms describing the relative functional relationship of the structures are used, such as "install", "connect", "connect", "fix", etc., they should be understood in a broad sense unless otherwise clearly specified and limited. For example, "install", "connect", "connect", etc. can be a fixed connection, a detachable connection, or an integrated one; can be a mechanical connection or an electrical connection; can be a direct connection or an indirect connection through an intermediate medium, can be the internal connection of two elements or the interaction relationship between two elements; "fix" can be an integrated fixation or a detachable fixation through fasteners; can be a direct fixation or a fixation through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above-mentioned descriptive terms in the present utility model can be understood according to the specific circumstances, the context, the coherence of the context, etc.

[0060] In the present invention, if there are descriptive terms with subsidiary or connecting meanings, for example, a first feature is "on" or "below" a second feature, unless otherwise clearly specified and limited, it should not be understood in a restrictive manner. For example, "on" or "below" may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above descriptive terms in the present invention can be understood according to the specific circumstances, the context, the coherence of the context, etc.

[0061] Furthermore, the first feature being “above”, “above”, and “above” the second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. The first feature being “below”, “below”, and “below” the second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0062] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in a suitable manner in any one or more embodiments or examples. In addition, those skilled in the art may combine and combine the different embodiments, examples and features of the different embodiments and examples described in this specification without contradiction, and these combinations or combinations shall all fall within the scope summarized by the utility model.

[0063] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are illustrative and cannot be construed as limitations on the present invention. A person skilled in the art can change, modify, replace and modify the above embodiments within the scope of information available from public channels and in combination with the technical inspiration provided by the present application documents.

Claims

1. A synchronous cylinder hydraulic system, characterized in that: The invention comprises a pressure oil circuit (1), an oil return circuit (2), a multi-way valve (3), a first oil cylinder (4), and a second oil cylinder (5); the pressure oil circuit (1) is connected to the pressure oil port of the multi-way valve (3), and the oil return circuit (2) is connected to the oil return port of the multi-way valve (3); the multi-way valve (3) is provided with a first working interface (6) and a second working interface (7); the first working interface (6) of the multi-way valve (3) is connected to the cylinder body side interface of the first oil cylinder (4), the piston rod side interface of the first oil cylinder (4) is connected to the cylinder body side interface of the second oil cylinder (5), and the piston rod side interface of the second oil cylinder (5) is connected to the second working interface (7) of the multi-way valve (3); The first oil cylinder (4) is also provided with a first compensation interface, the first compensation interface and the piston rod side interface of the first oil cylinder (4) are arranged at intervals along the axial direction of the first oil cylinder (4); the first compensation interface is provided with a first check valve (8), the outlet of the first check valve (8) is connected to the cylinder body side of the second oil cylinder (5); The second oil cylinder (5) is also provided with a second compensation interface, and the second compensation interface and the cylinder body side interface of the second oil cylinder (5) are arranged at intervals along the axial direction of the second oil cylinder (5); the second compensation interface is provided with a second one-way valve (9), and the outlet of the second one-way valve (9) is connected to the piston rod side of the first oil cylinder (4).

2. The synchronous cylinder hydraulic system according to claim 1, characterized in that: The distance between the first compensation interface and the piston rod side interface of the first oil cylinder (4) is the piston length of the first oil cylinder (4).

3. The synchronous cylinder hydraulic system according to claim 1, characterized in that: The distance between the second compensation interface and the cylinder body side interface of the second oil cylinder (5) is the piston length of the second oil cylinder (5).

4. The synchronous cylinder hydraulic system according to claim 1, characterized in that: A first hydraulically controlled one-way valve (10) is also provided on the oil circuit from the first working interface (6) of the multi-way valve (3) to the first oil cylinder (4), and the control oil port of the first hydraulically controlled one-way valve (10) is connected to the second working interface (7) of the multi-way valve (3); a second hydraulically controlled one-way valve (11) is also provided on the oil circuit from the second working interface (7) of the multi-way valve (3) to the second oil cylinder (5), and the control oil port of the second hydraulically controlled one-way valve (11) is connected to the first working interface (6) of the multi-way valve (3).

5. The synchronous cylinder hydraulic system according to claim 1, characterized in that: It also includes a safety valve (12), the inlet of the safety valve (12) is connected to the pressure oil circuit (1), and the outlet of the safety valve (12) is connected to the return oil circuit (2).

6. The synchronous cylinder hydraulic system according to claim 1, characterized in that: It also includes a hydraulic pump (13) and an oil tank (14); the inlet of the hydraulic pump (13) and the oil return line (2) are respectively connected to the oil tank (14); and the outlet of the hydraulic pump (13) is connected to the pressure oil line (1).

7. The synchronous cylinder hydraulic system according to claim 6, characterized in that: An oil filter (15) is also provided on the oil line from the oil tank (14) to the hydraulic pump (13).

8. The synchronous cylinder hydraulic system according to claim 7, characterized in that: The oil filter (15) is also connected in parallel with a third one-way valve (16), and the third one-way valve (16) can allow oil to flow from the oil tank (14) to the hydraulic pump (13) in one direction.

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