Electric control load sensitive valve assembly, hydraulic system and tractor

Abstract

The utility model relates to the technical field of hydraulic control, in particular to an electric control load-sensitive valve assembly, a hydraulic system and a tractor, which comprises an oil inlet unit and a plurality of hydraulic output units which are connected in sequence, a main overflow valve and a diverter valve are connected in parallel between an oil inlet P and an oil return port T; the LS overflow valve and the constant flow valve are connected in parallel among the diverter valve, the control oil port and the oil return port T; the hydraulic output units form first four-position seven-way valves through internal valve rods respectively, the oil inlet P is communicated with an oil inlet of each first four-position seven-way valve, and a port A and a port B of each first four-position seven-way valve are communicated with a pair of corresponding working ports respectively. A valve rod of the first four-position seven-way valve is in transmission connection with an output shaft of the motor. The proportional valve has the advantages that the valve rod is controlled and pushed through the motor so as to reach the corresponding position, compared with a common proportional valve, the thrust of the motor is larger, and therefore the pollution resistance is higher.

Description

Technical Field

[0001] The utility model relates to the technical field of hydraulic control, in particular to an electronically controlled load-sensitive valve component, a hydraulic system and a tractor. Background Art

[0002] The informatization of tractor machinery is a crucial component of modern agricultural production and a key supporting technology for intelligent agricultural machinery. With the centralization of land, tractor horsepower is continuously increasing. In high-power hydraulic systems, load-sensing control is often employed to conserve energy and reduce oil heating. This system ensures that the pressure and flow supplied by the hydraulic pump (variable pump) precisely meet the load requirements, eliminating excessive energy loss.

[0003] Existing electronically controlled load-sensing systems typically utilize proportional valves for control. The proportional valve group's control feeds into the actuator, actuating it. For example, in patent number 201320165642.8, titled "Load Sensing System," the oil inlet of the proportional valve group is connected to the oil outlet of a variable displacement pump group, enabling the actuator to be controlled via the proportional valve. Existing electronically controlled load-sensing systems utilizing proportional valves generally suffer from poor oil contamination resistance. Utility Model Content

[0004] The technical problem to be solved by the utility model is to provide an electronically controlled load-sensing valve assembly, a hydraulic system and a tractor, so as to solve the shortcoming of poor oil contamination resistance of the electronically controlled load-sensing system in the prior art.

[0005] The technical solution of the utility model for solving the above technical problems is as follows: an electronically controlled load-sensitive valve assembly, comprising an oil inlet link and a plurality of hydraulic output links connected in sequence, the oil inlet link being provided with a main overflow valve, a diverter valve, an LS overflow valve, a constant flow valve, an oil inlet P and an oil return port T, the main overflow valve and the diverter valve being connected in parallel between the oil inlet P and the oil return port T, the LS overflow valve and the constant flow valve being connected in parallel between the diverter valve and the control oil port and the oil return port T; the plurality of hydraulic output links respectively form a first four-position seven-way valve through an internal valve stem, the oil inlet P being respectively connected to the oil inlet of each of the first four-position seven-way valves, the A and B ports of each of the first four-position seven-way valves being respectively connected to a corresponding pair of working ports; the valve stems of the first four-position seven-way valves are respectively transmission-connected to the output shaft of the motor.

[0006] The beneficial effects of the present invention are as follows: the main relief valve is used to control the maximum pressure of the system and protect the hydraulic system; the Ls relief valve controls the maximum pressure of the feedback signal; the function of the diverter valve is to unload the load in the neutral position; in a quantitative load-sensitive system, the oil of the quantitative pump is unloaded from the diverter valve when it is not working; in a variable system, it can protect the variable pump from pressure buildup when it is not working; the hydraulic output link adopts a four-position seven-way control to realize the control of the lifting, neutral, lowering and floating position of the actuator; the valve stem is pushed by the motor control to reach the corresponding position. Compared with ordinary proportional valves, the thrust of the motor is greater, so the pollution resistance is stronger.

[0007] On the basis of the above technical solution, the present invention can also be improved as follows.

[0008] Furthermore, it also includes an electronically controlled lifting link, which is connected in parallel with multiple hydraulic output links. The electronically controlled lifting link forms a second four-position seven-way valve through an internal valve stem. The A and B ports of the second four-position seven-way valve are connected to the corresponding working ports, and the valve stems of the second four-position seven-way valve are respectively connected to the output shaft of the motor.

[0009] The beneficial effect of adopting the above further solution is that the setting of the electric-controlled lifting link can realize the lifting and lowering of the machine, control the tillage depth or lifting height of the machine, and meet different operation requirements.

[0010] Furthermore, port A of the second four-position seven-way valve is connected to a hydraulically controlled one-way valve.

[0011] The beneficial effect of adopting the above further solution is that the provision of the hydraulically controlled one-way valve can prevent the oil pressure of the actuator from being too high.

[0012] Furthermore, a pressure compensation valve is provided in the hydraulic output link, and the pressure compensation valve is connected to the first four-position seven-way valve.

[0013] The beneficial effect of adopting the above-mentioned further scheme is that the setting of the pressure compensation valve can make the oil flow rate output flow to each actuator in proportion to the opening area of ​​the valve stem in each hydraulic output link, avoiding the oil flow to the low-load hydraulic output link, causing the action of the high-load part to run slowly or stagnate, thereby ensuring that each hydraulic output link can operate normally.

[0014] Furthermore, the number of the hydraulic output links is 5.

[0015] The beneficial effect of adopting the above further solution is: realizing the control of multiple execution elements.

[0016] Furthermore, port A of the second four-position seven-way valve is connected to a hydraulically controlled one-way valve.

[0017] The beneficial effect of adopting the above further solution is that the provision of the hydraulically controlled one-way valve can prevent the oil pressure of the actuator from being too high.

[0018] The utility model solves the above technical problem and further provides a hydraulic system including the above-mentioned electronically controlled load-sensing valve assembly.

[0019] The beneficial effects of adopting the above scheme are: the main relief valve is used to control the maximum pressure of the system and protect the hydraulic system, the Ls relief valve controls the maximum pressure of the feedback signal, and the function of the diverter valve is to unload the load in the neutral position. In the quantitative load-sensitive system, the oil of the quantitative pump is unloaded from the diverter valve when it is not working; in the variable system, it can protect the variable pump from pressure buildup when it is not working; the hydraulic output link adopts a four-position seven-way control to realize the control of the actuator lifting, neutral, lowering and floating position; the valve stem is pushed by the motor control to reach the corresponding position. Compared with the ordinary proportional valve, the thrust of the motor is greater, so it has stronger pollution resistance.

[0020] The utility model solves the above technical problem and further provides a tractor, comprising the above hydraulic system.

[0021] The beneficial effects of adopting the above scheme are: the main relief valve is used to control the maximum pressure of the system and protect the hydraulic system, the Ls relief valve controls the maximum pressure of the feedback signal, and the function of the diverter valve is to unload the load in the neutral position. In the quantitative load-sensitive system, the oil of the quantitative pump is unloaded from the diverter valve when it is not working; in the variable system, it can protect the variable pump from pressure buildup when it is not working; the hydraulic output link adopts a four-position seven-way control to realize the control of the actuator lifting, neutral, lowering and floating position; the valve stem is pushed by the motor control to reach the corresponding position. Compared with the ordinary proportional valve, the thrust of the motor is greater, so it has stronger pollution resistance. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a structural diagram of the utility model;

[0023] In the accompanying drawings, the components represented by the reference numerals are as follows:

[0024] 1. Hydraulic output link; 2. Main relief valve; 3. Diverter valve; 4. LS relief valve; 5. Constant flow valve; 6. Oil inlet P; 7. Oil return port T; 8. First four-position seven-way valve; 9. Electric control lifting link; 10. Second four-position seven-way valve; 11. Hydraulic control one-way valve; 12. Pressure compensation valve. DETAILED DESCRIPTION

[0025] 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.

[0026] Example 1

[0027] like Figure 1As shown, this embodiment discloses an electronically controlled load-sensitive valve assembly, comprising an oil inlet link and a plurality of hydraulic output links 1 connected in sequence, wherein the oil inlet link is provided with a main relief valve 2, a diverter valve 3, an LS relief valve 4, a constant flow valve 5, an oil inlet P6 and an oil return port T7, the main relief valve 2 and the diverter valve 3 are connected in parallel between the oil inlet P6 and the oil return port T7, the LS relief valve 4 and the constant flow valve 5 are connected in parallel between the diverter valve 3 and the control oil port and the oil return port T7; the plurality of hydraulic output links 1 respectively form a first four-position seven-way valve 8 through an internal valve stem, the oil inlet P6 is respectively connected to the oil inlet of each of the first four-position seven-way valves 8, and the A (working oil inlet) and B (working oil return) ports of each of the first four-position seven-way valves 8 are respectively connected to a corresponding pair of working ports; the valve stems of the first four-position seven-way valves 8 are respectively transmission-connected to the output shaft of the motor.

[0028] In this embodiment, the number of the hydraulic output links 1 is 5, and the A and B ports of the 5 first four-position seven-way valves 8 are A1 port B1 port, A2 port B2 port, A3 port B3 port, A5 port B5 port, and A6 port B6 port, respectively, for connecting to 5 corresponding actuators.

[0029] In this embodiment, an electric-controlled lifting link 9 is also included. The electric-controlled lifting link 9 is connected in parallel with the plurality of hydraulic output links 1. The electric-controlled lifting link 9 forms a second four-position seven-way valve 10 through an internal valve stem. The A (working oil inlet) and B (working oil return) ports of the second four-position seven-way valve 10 are connected to the corresponding working ports. Figure 1 In the figure, the A and B ports of the second four-position seven-way valve 10 correspond to the A4 port and the B4 port, and the valve stem of the second four-position seven-way valve 10 is respectively connected to the output shaft of the motor. The setting of the electric lifting link 9 can realize the lifting and lowering of the machine, control the tillage depth or lifting height of the machine, and meet different operation requirements.

[0030] In this embodiment, port A of the second four-position seven-way valve 10 is connected to a hydraulically controlled one-way valve 11. Port A of the second four-position seven-way valve 10 is connected to a hydraulically controlled one-way valve 11. The setting of the hydraulically controlled one-way valve 11 can prevent the oil pressure of the actuator from being too high.

[0031] In this embodiment, a pressure compensating valve 12 is provided in the hydraulic output link 1, and the pressure compensating valve 12 is connected to the first four-position seven-way valve 8. Specifically, the oil inlet and the control oil port at one end of the pressure compensating valve 12 are connected to the corresponding C port of the first four-position seven-way valve 8 and the second four-position seven-way valve 10, and the A port of the pressure compensating valve 12 is connected to the D port and LS port of the corresponding first four-position seven-way valve 8 and the second four-position seven-way valve 10, so that after each first four-position seven-way valve 8 and the second four-position seven-way valve 10 are switched, they are connected to the oil inlet P6, the oil return port T7 and the corresponding pair of working ports through the pressure compensating valve 12.

[0032] Example 2

[0033] This embodiment discloses a hydraulic system, including the electronically controlled load-sensing valve assembly described in the above embodiment.

[0034] Example 3

[0035] This embodiment discloses a tractor, comprising the hydraulic system described in the above embodiment.

[0036] The main relief valve 2 of the utility model is used to control the maximum pressure of the system and protect the hydraulic system. The LS relief valve 4 controls the maximum pressure of the feedback signal. The function of the diverter valve 3 is to unload the load in the neutral position. In the quantitative load-sensitive system, the oil of the quantitative pump is unloaded from the diverter valve 3 when it is not working; in the variable system, it can protect the variable pump from pressure buildup when it is not working; the hydraulic output link 1 adopts a four-position seven-way control to realize the control of the lifting, neutral, lowering and floating position of the actuator; the valve stem is pushed by the motor control to reach the corresponding position. Compared with the ordinary proportional valve, the thrust of the motor is greater, so the pollution resistance is stronger.

[0037] In the description of the present invention, it should be understood that the terms "center", "length", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "inside", "outside", "peripheral", "circumferential" and the like indicating orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the system or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0038] In the description of the present invention, “a plurality of” means at least two, such as two, three, etc., unless otherwise clearly defined.

[0039] In this utility model, unless otherwise specified or limited, the terms "installed," "connected," "connect," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection; direct connection, or indirect connection through an intermediate medium; internal communication between two components, or interaction between two components, unless otherwise specified. Those skilled in the art will understand the specific meanings of the above terms in this utility model based on specific circumstances.

[0040] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" 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 present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and features of different embodiments or examples without contradiction.

[0041] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. An electronically controlled load-sensing valve assembly, characterized in that: The invention comprises an oil inlet link and a plurality of hydraulic output links (1) connected in sequence, wherein the oil inlet link is provided with a main overflow valve (2), a diverter valve (3), an LS overflow valve (4), a constant flow valve (5), an oil inlet P (6) and an oil return port T (7), wherein the main overflow valve (2) and the diverter valve (3) are connected in parallel between the oil inlet P (6) and the oil return port T (7), and the LS overflow valve (4) and the constant flow valve (5) are connected in parallel between the diverter valve (3) and the control oil port and the oil return port T (7); the plurality of hydraulic output links (1) respectively form a first four-position seven-way valve (8) through an internal valve stem, wherein the oil inlet P (6) is respectively communicated with the oil inlet of each of the first four-position seven-way valves (8), and the A and B ports of each of the first four-position seven-way valves (8) are respectively communicated with a corresponding pair of working ports; and the valve stems of the first four-position seven-way valves (8) are respectively connected to the output shaft of the motor in a transmission manner.

2. An electrically controlled load sensing valve assembly according to claim 1, characterized in that: The invention also includes an electrically controlled lifting link (9), which is connected in parallel with the plurality of hydraulic output links (1). The electrically controlled lifting link (9) forms a second four-position seven-way valve (10) through an internal valve stem. The A and B ports of the second four-position seven-way valve (10) are connected to corresponding working ports, and the valve stems of the second four-position seven-way valve (10) are respectively connected to the output shaft of the motor.

3. The electronically controlled load sensing valve assembly according to claim 2, characterized in that: The port A of the second four-position seven-way valve (10) is connected to a hydraulically controlled one-way valve (11).

4. The electronically controlled load sensing valve assembly according to claim 1, characterized in that: A pressure compensation valve (12) is provided in the hydraulic output link (1), and the pressure compensation valve (12) is connected to the first four-position seven-way valve (8).

5. The electronically controlled load sensing valve assembly according to claim 1, characterized in that: The number of the hydraulic output links (1) is 5.

6. The electronically controlled load sensing valve assembly according to claim 2, characterized in that: The port A of the second four-position seven-way valve (10) is connected to a hydraulically controlled one-way valve (11).

7. A hydraulic system, characterized in that: The invention comprises an electrically controlled load sensing valve assembly according to any one of claims 1 to 6.

8. A tractor, characterized in that: Comprising a hydraulic system as claimed in claim 7.

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