An electric proportional flow control valve

Abstract

The present invention relates to an electric proportional flow control valve, comprising an electric proportional control pilot stage part and a hydraulically controlled main stage part, wherein the pilot stage part comprises an electromagnet, a pilot valve sleeve, a pilot main valve core and a pilot cone valve core, wherein the electromagnet controls the movement of the pilot cone valve core, the movement of the pilot cone valve core controls the movement of the pilot main valve core, and the mutual movement of the pilot main valve core and the pilot valve sleeve can control the flow direction of the hydraulic oil of a third control oil circuit and a second control oil circuit; the main stage part comprises a main spring, a main spring seat and a first main valve core without a one-way valve hole or a second main valve core with a one-way valve hole, and under the action of the flow direction of the hydraulic oil of the third control oil circuit and the second control oil circuit, controls the proportional opening and closing of the flow of the hydraulic oil from the first control oil circuit to the second control oil circuit.

Description

Technical Field

[0001] The invention relates to an electric proportional flow control valve, mainly to a pilot stage part of electric proportional control and a main stage part of hydraulic control, wherein the pilot stage part of the electric proportional control controls the proportional opening of the main stage part of hydraulic control. Background Art

[0002] In the hydraulic system, the movement speed of the actuator depends on the flow of the system. For a single pump with multiple actuators, a control valve is required to distribute the flow. The hydraulic system of the excavator is a typical machine with a single pump and multiple actuators. The electronically controlled hydraulic system is the development direction of the future excavator system. This system mostly uses an electric proportional pressure reducing valve to control the movement of the valve core to control the system flow. Since the system consists of multiple actuators and each actuator has different loads and the working conditions of each actuator are complex, only controlling the flow through the valve core cannot meet all the action requirements of the actuator. Based on this shortcoming, a new type of electric proportional flow control valve is designed. Summary of the invention

[0003] The object of the present invention is to provide a novel electric proportional flow control valve to solve the problems of the existing electric control hydraulic system, and to cooperate with the valve core to more accurately control the flow of the actuator.

[0004] An electric proportional flow control valve comprises an electric proportional control pilot stage part and a hydraulically controlled main stage part, wherein the pilot stage part comprises an electromagnet, a pilot valve sleeve, a pilot main valve core and a pilot cone valve core, wherein the electromagnet controls the movement of the pilot cone valve core, and the movement of the pilot cone valve core controls the movement of the pilot main valve core, and the mutual movement of the pilot main valve core and the pilot valve sleeve can control the flow direction of the hydraulic oil of a third control oil circuit and a second control oil circuit; the main stage part comprises a main spring, a main spring seat and a first main valve core without a one-way valve hole or a second main valve core with a one-way valve hole, and controls the proportional opening and closing of the flow of the hydraulic oil from the first control oil circuit to the second control oil circuit under the action of the flow direction of the hydraulic oil of the third control oil circuit and the second control oil circuit.

[0005] Furthermore, when the main stage part adopts the second main valve core with a one-way valve hole, it also includes a throttling screw plug, a throttling one-way valve spring, a throttling one-way valve core, a one-way valve screw plug, a one-way valve spring and / or a one-way valve core.

[0006] Furthermore, when the electromagnet of the pilot stage is energized, the hydraulic oil in the third control oil circuit flows to the second control oil circuit; when the electromagnet is de-energized, the hydraulic oil in the second control oil circuit flows to the third control oil circuit, and the hydraulic oil in the third control oil circuit cannot flow to the second control oil circuit.

[0007] Furthermore, when the electromagnet of the pilot stage part is energized, and the third control oil circuit and the fourth control oil circuit flow to the second control oil circuit through the pilot stage part, the first main valve core or the second main valve core moves to make the hydraulic oil of the first control oil circuit flow to the second control oil circuit; when the electromagnet loses power, the third control oil circuit and the fourth control oil circuit are closed chambers, the first main valve core or the second main valve core is in the initial position, and the hydraulic oil of the first control oil circuit cannot flow to the second control oil circuit.

[0008] Compared with the prior art, the present invention has the following beneficial effects:

[0009] 1. Independent control of oil inlet and oil return can be achieved. The electric proportional flow control valve of the present invention can be used in conjunction with valve core control to separately control the oil inlet flow and oil return flow of the hydraulic system.

[0010] 2. More precise flow control: The electric proportional flow control valve of the present invention can precisely control the flow of the actuator as required. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 It is a schematic diagram of the hydraulic structure of the present invention.

[0012] Figure 2 It is a schematic structural diagram of the pilot stage part of the present invention.

[0013] Figure 3 It is a structural schematic diagram of the main stage part of the present invention.

[0014] Figure 4 Another structural schematic diagram of the main stage part of the present invention.

[0015] In the figure:

[0016] 1- Pilot stage of electric proportional control 2- Main stage of hydraulic control 3- Fourth control oil circuit

[0017] 4- Third control oil circuit 5- Second control oil circuit 6- First control oil circuit

[0018] 7-valve core assembly 8-valve body 1.1-electromagnet

[0019] 1.2-pilot valve sleeve 1.3-pilot main valve core 1.4-pilot cone valve core

[0020] 2.1- Main spring 2.2- Main spring seat 2.3- The first main valve core

[0021] 2.4-Throttling screw plug 2.5-Throttling check valve spring 2.6-Throttling check valve core

[0022] 2.7- One-way valve plug 2.8- One-way valve spring 2.9- One-way valve core

[0023] 2.10-The second main valve core. DETAILED DESCRIPTION

[0024] The specific implementation modes of the present invention are further described in detail below in combination with the accompanying drawings. However, the following embodiments only list preferred embodiments, which only serve to explain and illustrate the present invention and cannot be understood as limiting the present invention.

[0025] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions.

[0026] like Figure 1 As shown, this hydraulic circuit structure diagram only shows the elements used to illustrate the principles of the present invention, and omits some basic elements in the hydraulic circuit, such as the overflow valve, the pilot electric proportional pressure reducing valve and other elements. Since these elements do not affect the description of the principles of the present invention, they are omitted in the description of the present invention.

[0027] like Figure 1 As shown, the present invention comprises an electric proportional control pilot stage part 1 , a hydraulic control main stage part 2 , a valve core assembly 7 and a valve body 8 .

[0028] The pilot stage part 1 of the electric proportional control comprises an electromagnet 1.1, a pilot valve sleeve 1.2, a pilot main valve core 1.3 and a pilot cone valve core 1.4.

[0029] The pilot stage part 1 of the electric proportional control controls the flow direction of the hydraulic oil in the third control oil circuit 4 and the second control oil circuit 5 .

[0030] The main stage part 2 of the hydraulic control at least includes a main spring 2.1, a main spring seat 2.2, a first main valve core 2.3 or a second main valve core 2.10, and may also selectively include a throttle screw plug 2.4, a throttle check valve spring 2.5, a throttle check valve core 2.6, a check valve screw plug 2.7, a check valve spring 2.8, and a check valve core 2.9. For example, the main stage part 2 of the hydraulic control includes the main spring 2.1, the main spring seat 2.2, and the first main valve core 2.3, which is the first example of this description. The main stage part 2 of the hydraulic control includes the main spring 2.1, the main spring seat 2.2, the second main valve core 2.10, the throttle screw plug 2.4, the throttle check valve spring 2.5, the throttle check valve core 2.6, the check valve screw plug 2.7, the check valve spring 2.8, and the check valve core 2.9, which is the second example of this description. The first example of the main stage part 2 of the hydraulic control is the simplest combination form, and the second example is the most complex combination form. Different examples can also be combined by including several parts in 2.4~2.9.

[0031] The main stage part 2 of the hydraulic control controls the opening and closing of the ratio of the flow of hydraulic oil from the first control oil circuit 6 to the second control oil circuit 5 .

[0032] In the main stage part 2 of the hydraulic control, the hydraulic oil of the fourth control oil circuit 3 can flow directly to the third control oil circuit 4; or, the hydraulic oil of the fourth control oil circuit 3 can flow to the third control oil circuit 4 through the throttling screw plug 2.4; or, the hydraulic oil of the fourth control oil circuit 3 can flow to the third control oil circuit 4 through the throttling screw plug 2.4 and then through the throttling check valve core 2.6.

[0033] In the main stage part 2 of the hydraulic control, the hydraulic oil of the third control oil circuit 4 can flow directly to the fourth control oil circuit 3; or, the hydraulic oil of the third control oil circuit 4 can flow to the fourth control oil circuit 3 through the throttling screw plug 2.4; or, the hydraulic oil of the third control oil circuit 4 can flow to the fourth control oil circuit 3 through the throttling screw plug 2.4 and then through the throttling check valve core 2.6.

[0034] In the main stage part 2 of the hydraulic control, the hydraulic oil of the first control oil circuit 6 can flow to the second control oil circuit 5 through the first main valve core 2.3 or the second main valve core 2.10.

[0035] In the main stage part 2 of the hydraulic control, the hydraulic oil of the first control oil circuit 6 can flow to the third control oil circuit 4 through the throttling formed by the first main valve core 2.3 and the valve body 8; or, the hydraulic oil of the first control oil circuit 6 can flow to the third control oil circuit 4 through the one-way valve core 2.9 and then through the throttling formed by the second main valve core 2.10 and the valve body 8.

[0036] In the main stage part 2 of the hydraulic control, the hydraulic oil of the first control oil circuit 6 flows to the fourth control oil circuit 3 through the third control oil circuit 4 .

[0037] In the main stage part 2 of the hydraulic control, the main spring 2.1 keeps the first main valve core 2.3 or the second main valve core 2.10 in the initial position when not in operation. The throttle check valve spring 2.5 keeps the throttle check valve core 2.6 in the initial position when not in operation. The check valve spring keeps the check valve core in the initial position when not in operation.

[0038] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations on the present invention. A person skilled in the art may change, modify, replace and modify the above embodiments within the scope of the present invention without departing from the principles and purpose of the present invention. Simple combination changes thereof are all within the protection of the present invention.

Claims

1. An electric proportional flow control valve, comprising an electric proportional control pilot stage part (1) and a hydraulic control main stage part (2), characterized in that: The pilot stage part (1) comprises an electromagnet (1.1), a pilot valve sleeve (1.2), a pilot main valve core (1.3) and a pilot cone valve core (1.4); the electromagnet (1.1) controls the movement of the pilot cone valve core (1.4); the movement of the pilot cone valve core (1.4) controls the movement of the pilot main valve core (1.3); the mutual movement of the pilot main valve core (1.3) and the pilot valve sleeve (1.2) can control the flow direction of the hydraulic oil in the third control oil circuit (4) and the second control oil circuit (5); The main stage part (2) comprises a main spring (2.1), a main spring seat (2.2) and a main valve core (2.10) with a one-way valve hole, and controls the proportional opening and closing of the flow of hydraulic oil from the first control oil circuit (6) to the second control oil circuit (5) under the influence of the flow direction of hydraulic oil in the third control oil circuit (4) and the second control oil circuit (5); when the electromagnet (1.1) of the pilot stage part (1) is energized, the hydraulic oil in the third control oil circuit (4) flows to the second control oil circuit (5); When the electromagnet (1.1) loses power, the hydraulic oil in the second control oil circuit (5) flows to the third control oil circuit (4), and the hydraulic oil in the third control oil circuit (4) cannot flow to the second control oil circuit (5); when the electromagnet (1.1) of the pilot stage part (1) is energized, and the third control oil circuit (4) and the fourth control oil circuit (3) flow to the second control oil circuit (5) through the pilot stage part (1), the main valve core (2.10) moves to make the hydraulic oil in the first control oil circuit (6) flow to the second control oil circuit (5). When the electromagnet (1.1) loses power, the third control oil circuit (4) and the fourth control oil circuit (3) are closed chambers, the main valve core (2.10) is in an initial position, and the hydraulic oil in the first control oil circuit (6) cannot flow to the second control oil circuit (5); the main valve core (2.10) further includes a throttle screw plug (2.4), a throttle check valve spring (2.5), a throttle check valve core (2.6), a check valve screw plug (2.7), a check valve spring (2.8) and a check valve core (2.9).

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