Electro-hydraulic control valve

Abstract

An electro-hydraulic control valve according to an embodiment of the present invention comprises: a valve body including a plurality of spool receiving portions formed parallel to each other, a plurality of first supply passages each connected to one side area of ​​the plurality of spool receiving portions, a plurality of second supply passages each connected to the other side area of ​​the plurality of spool receiving portions, a parallel passage formed in a direction intersecting the plurality of spool receiving portions and spaced apart from the plurality of spool receiving portions, and a plurality of connecting passages each connecting the parallel passages and the central area of ​​the plurality of spool receiving portions; a plurality of control spools each movably installed in the plurality of spool receiving portions to control the direction of movement of the hydraulic fluid according to positional movement; and a plurality of check valves each installed at the confluence point of the parallel passages and the plurality of connecting passages to restrict the movement of the hydraulic fluid in the direction of the parallel passages from the plurality of connecting passages.

Description

Technology Field

[0001] The present invention relates to construction machinery, and more specifically, to a flow control assembly capable of controlling the speed of a boom and a construction machine equipped with the same. Background Technology

[0002] Construction machinery broadly refers to all machinery used in civil engineering or construction work. Generally, construction machinery has an engine and a hydraulic pump that operates using the engine's power, and it drives or operates work devices using the power generated through the engine and hydraulic pump.

[0003] For example, an excavator, which is a type of construction machine, is a construction machine that performs tasks such as excavation work to dig the ground, loading work to transport soil, crushing work to demolish buildings, and leveling work to prepare the ground at civil engineering, construction, and construction sites. It consists of a driving body that serves as the moving part of the equipment, an upper slewing body mounted on the driving body that rotates 360 degrees, and a working device.

[0004] In addition, the excavator includes drive devices such as a travel motor used for travel, a swing motor used for the swing of the upper slewing body, and boom cylinders, arm cylinders, bucket cylinders, and optional cylinders used for the working device. These drive devices are driven by hydraulic fluid discharged from a variable displacement hydraulic pump driven by an engine or an electric motor, and the hydraulic fluid discharged from the hydraulic pump is distributed to each drive device by a hydraulic control valve having multiple control spools. That is, the hydraulic control valve has multiple control spools proportional to the number of drive devices to be controlled.

[0005] Furthermore, in conventional hydraulic control valves based on mechanical control, multiple passages such as a center bypass passage, a driving signal passage, and an auto-idle passage are formed within the valve body for mechanical control; consequently, not only is the overall structure complex, but the size is also inevitably large.

[0006] Recently, electronically controlled hydraulic control valves have become widely available, but they were being used by simply changing the control method of the valve body of a mechanically controlled hydraulic control valve to electronic.

[0007] However, conventional mechanically controlled hydraulic control valves have a problem in that their valve bodies are unnecessarily complex in structure and large in size, making them unsuitable for electronic control systems. The problem to be solved

[0008] An embodiment of the present invention provides an electro-hydraulic control valve that can simplify the overall structure and reduce the size. means of solving the problem

[0009] According to an embodiment of the present invention, an electro-hydraulic control valve comprises a valve body including a plurality of spool receiving portions formed parallel to each other, a plurality of first supply passages each connected to one side area of ​​the plurality of spool receiving portions, a plurality of second supply passages each connected to the other side area of ​​the plurality of spool receiving portions, a parallel passage formed in a direction intersecting the plurality of spool receiving portions and spaced apart from the plurality of spool receiving portions, and a plurality of connecting passages each connecting the parallel passages and the central area of ​​the plurality of spool receiving portions; a plurality of control spools each movably installed in the plurality of spool receiving portions to control the direction of movement of the hydraulic fluid according to positional movement; and a plurality of check valves each installed at the confluence point of the parallel passages and the plurality of connecting passages to restrict the movement of the hydraulic fluid in the direction of the parallel passages from the plurality of connecting passages.

[0010] The above-described electro-hydraulic control valve may further include a plurality of electro-proportional pressure reducing valves that regulate the pilot pressure applied to one end of the plurality of control spools in proportion to the input current signal.

[0011] The plurality of check valves are positioned offset to be relatively adjacent to any one of the plurality of first supply passages and the plurality of second supply passages, and the plurality of connecting passages may be formed offset to be relatively adjacent to the other of the plurality of first supply passages and the plurality of second supply passages.

[0012] The valve body may further include a plurality of relief valve couplings each connected to the plurality of first supply passages and the plurality of second supply passages. Additionally, the electro-hydraulic control valve may further include an overload relief valve installed in each of the plurality of relief valve couplings to reduce peak pressure generated in the plurality of first supply passages and the plurality of second supply passages.

[0013] Each of the above multiple connecting channels may include an inclined section.

[0014] The above-mentioned spool receiving portion has a length in the transverse direction of the valve body and can be arranged in parallel in two rows along the longitudinal direction of the valve body.

[0015] The first supply path, the second supply path, the connecting path, and the check valve are arranged in a plurality of rows along the longitudinal direction of the valve body, and the rows may be symmetrical to each other.

[0016] Additionally, the spool receiving portion may have a length in the transverse direction of the valve body and a plurality of them may be arranged in a parallel row along the longitudinal direction of the valve body, and a pair of the valve bodies may be combined such that the first supply path, the second supply path, the connecting path, and the check valve are each symmetrical to each other. Effects of the invention

[0017] According to an embodiment of the present invention, the electro-hydraulic control valve can simplify the overall structure and reduce the size. Brief explanation of the drawing

[0018] FIG. 1 is a cross-sectional view of an electro-hydraulic control valve according to one embodiment of the present invention. Figure 2 is a cross-sectional view of an electro-hydraulic control valve along line II-II of Figure 1. Figure 3 is a cross-sectional view of an electro-hydraulic control valve along line III-III of Figure 2. Figure 4 is an enlarged cross-sectional view of the check valve and the connecting path in Figure 2. FIG. 5 is a cross-sectional view of an electro-hydraulic control valve according to a modified example of one embodiment of the present invention. Specific details for implementing the invention

[0019] Hereinafter, embodiments of the present invention will be described in detail with reference to the attached drawings so that those skilled in the art can easily implement the present invention. The present invention may be embodied in various different forms and is not limited to the embodiments described herein.

[0020] It should be noted that the drawings are schematic and not drawn to scale. The relative dimensions and proportions of parts in the drawings are exaggerated or reduced in size for clarity and convenience in the drawings, and any dimensions are merely illustrative and not limiting. Additionally, the same reference numerals are used to denote similar features for the same structure, element, or part appearing in two or more drawings.

[0021] The embodiments of the present invention specifically illustrate ideal embodiments of the present invention. As a result, various variations of the illustration are expected. Accordingly, the embodiments are not limited to the specific form of the illustrated area and include, for example, variations in form resulting from manufacturing.

[0022] Hereinafter, an electro-hydraulic control valve (101) according to an embodiment of the present invention will be described with reference to FIGS. 1 to 4.

[0023] For example, the electronic hydraulic control valve (101) can not only distribute the hydraulic fluid discharged by the hydraulic pump in the construction machine to various drive devices, but also switch the direction of operation of each drive device.

[0024] As illustrated in FIGS. 1 to 3, an electro-hydraulic control valve (101) according to one embodiment of the present invention includes a valve body (200), a plurality of control spools (300), and a plurality of check valves (400).

[0025] An electronic hydraulic control valve (101) according to one embodiment of the present invention may further include a plurality of electronic proportional pressure reducing valves (EPPRV) (500) and overload relief valves (700).

[0026] The valve body (200) may include a plurality of spool receiving portions (230), a plurality of first supply passages (261), a plurality of second supply passages (262), a parallel passage (250), and a plurality of connecting passages (240).

[0027] Additionally, the valve body (200) may further include a plurality of relief valve coupling parts (270).

[0028] A plurality of spool receiving portions (230) may be formed parallel to each other. For example, a plurality of spool receiving portions (230) may have a length in the horizontal direction of the valve body (200) and may be arranged in parallel in two rows along the vertical direction of the valve body (200). Additionally, a plurality of control spools (300), which will be described later, may each be movably received in the plurality of spool receiving portions (230).

[0029] A plurality of first supply channels (261) can each be connected to one side area of ​​a plurality of spool receiving portions (230).

[0030] A plurality of second supply channels (262) can each be connected to the other side of a plurality of spool receiving portions (230).

[0031] The parallel passage (250) may be formed spaced apart from the plurality of spool receiving portions (230) and in a direction intersecting the plurality of spool receiving portions (230). For example, if the plurality of spool receiving portions (230) are formed to have a length in the horizontal direction of the valve body (200), the parallel passage (250) may be formed to have a length in the vertical direction of the valve body (200). The parallel passage (250) may receive hydraulic fluid from the outside, and the hydraulic fluid flowing into the parallel passage (250) moves toward each spool receiving portion (230). For example, hydraulic fluid discharged by a hydraulic pump may flow into the parallel passage (250).

[0032] Multiple connecting channels (240) can each connect the central region of the parallel channels (250) and the multiple spool receiving portions (230).

[0033] A plurality of relief valve coupling portions (270) can be connected to a plurality of first supply passages (261) and a plurality of second supply passages (262), respectively.

[0034] It can be formed to be connected to one or more of the two ends of each of the plurality of spool receiving portions (230). Each of the plurality of relief valve coupling portions (270) may be equipped with an overload relief valve (700) to be described later.

[0035] Additionally, a first supply path (261), a second supply path (262), a connecting path (240), an electronic proportional pressure reducing valve coupling part (270), and a check valve (400) to be described later may be arranged in a plurality of rows along the longitudinal direction of the valve body (200), and the first supply path (261), second supply path (262), connecting path (240), electronic proportional pressure reducing valve coupling part (270), and check valve (400) of different rows may be formed symmetrically.

[0036] A plurality of control spools (300) can be movably installed in each of the plurality of spool receiving portions (230). And the direction of movement of the hydraulic fluid can be controlled according to the positional movement of the plurality of control spools (300).

[0037] A plurality of control spools (300) may be provided in proportion to the number of drive devices to be controlled by the electro-hydraulic control valve (101). For example, if the electro-hydraulic control valve (101) is used in a construction machine such as an excavator, the electro-hydraulic control valve (101) can control the supply of hydraulic fluid to drive devices such as a drive motor used for driving, a swing motor used for swinging the upper slewing body, a boom cylinder, an arm cylinder, a bucket cylinder, and an optional cylinder used for the working device, and includes control spools (300) corresponding to the number of drive devices to be controlled.

[0038] Additionally, depending on the positional movement of the control spool (300), the hydraulic fluid flowing into the spool receiving portion (230) through the connecting channel (240) moves to one of the first supply channel (261) or the second supply channel (262).

[0039] For example, in the case of a slewing motor, it can turn left when receiving hydraulic fluid through the first supply path (261) of the electro-hydraulic control valve (101), and turn right when receiving hydraulic fluid through the second supply path (262). Also, in the case of a cylinder, it can extend when receiving hydraulic fluid through the first supply path (261) of the electro-hydraulic control valve (101), and contract when receiving hydraulic fluid through the second supply path (262).

[0040] A plurality of check valves (400) may each be installed at the junction of a parallel flow path (250) and a plurality of connecting flow paths (240). The plurality of check valves (400) may restrict the movement of working fluid from the plurality of connecting flow paths (240) toward the parallel flow path (250).

[0041] An overload relief valve (700) is installed in each of the multiple relief valve coupling parts (270) to reduce the peak pressure generated in the multiple first supply paths (261) and multiple second supply paths (262).

[0042] The check valve (400) can protect the hydraulic pump by preventing the hydraulic fluid from flowing back into the hydraulic pump when the pressure of the hydraulic fluid rises rapidly and instantaneously during the operation of various drive devices. In addition, if the check valve (400) completely blocks the flow of the hydraulic fluid, it can prevent the drive device, such as a boom cylinder, from sagging due to its own weight.

[0043] Additionally, a plurality of check valves (400) may be positioned so as to be relatively adjacent to one of the plurality of first supply channels (261) and the plurality of second supply channels (262) between the plurality of first supply channels (261) and the plurality of second supply channels (262).

[0044] And a plurality of connecting channels (240) may be formed offset so as to be relatively adjacent to one of the plurality of first supply channels (261) and the plurality of second supply channels (262) between the plurality of first supply channels (261) and the plurality of second supply channels (262).

[0045] In this way, by arranging multiple check valves (400) at an angle, space to form multiple connecting passages (240) can be secured, and the overall size of the valve body (200) can be reduced.

[0046] Additionally, as illustrated in FIG. 4, a plurality of connecting passages (240) may each include an inclined section (s). Specifically, the connecting passage (240) is connected to a parallel passage (250) with the check valve (400) in between. At this time, the connecting passage (240) is positioned to be offset from the check valve (400) and has an inclined section (s), thereby reducing pressure loss. That is, the further the check valve (400) is offset from the center, the longer the inclined section of the connecting passage (240) can be secured, thereby further reducing pressure loss.

[0047] A plurality of electronic proportional pressure reducing valves (EPPRV) (700) can adjust the pilot pressure applied to one end of a plurality of control spools (300) in proportion to the input current signal. The plurality of control spools (300) move according to the pilot pressure to control the flow of hydraulic fluid.

[0048] In this way, the electronic hydraulic control valve (101) according to one embodiment of the present invention is controlled in an electronic control manner in which the control spool (300) is controlled according to a current signal input to the electronic proportional pressure reducing valve (700).

[0049] With such a configuration, the electro-hydraulic control valve (101) according to one embodiment of the present invention can simplify the overall structure and reduce the size.

[0050] In particular, it may have a valve body (200) suitable for an electro-hydraulic control valve (101) controlled by an electronic control method using an electric current signal.

[0051] Hereinafter, a modified example of an embodiment of the present invention will be described with reference to FIG. 5.

[0052] As illustrated in FIG. 5, in an electro-hydraulic control valve (102) according to a modified example of an embodiment of the present invention, a plurality of spool receiving portions (230) may have a length in the transverse direction of the valve body (201, 202) and may be arranged in parallel in a row along the longitudinal direction of the valve body (201, 202). In addition, a pair of valve bodies (201, 202) may be combined such that the first supply passage (261), the second supply passage (262), the connecting passage (240), and the check valve (400) are each symmetrical to each other.

[0053] In this way, according to a modified example of one embodiment of the present invention, multiple flow paths can be easily machined inside the valve body (201, 202).

[0054] Although embodiments of the present invention have been described above with reference to the attached drawings, those skilled in the art to which the present invention pertains will understand that the present invention may be implemented in other specific forms without changing its technical concept or essential features.

[0055] Therefore, the embodiments described above should be understood as illustrative in all respects and not limiting, and the scope of the invention is defined by the claims set forth below, and all modifications or variations derived from the meaning and scope of the claims and equivalents thereof should be interpreted as being included within the scope of the invention. Explanation of the symbols

[0056] 101: Electro-hydraulic control valve 200, 201, 202: Valve body 230: Spool receiving section 240: Connect Euro 250: Parallel Euro 261: First supply Euro 262: Second supply Euro 270: Relief valve joint 300: Control spool 400: Check valve 500: Electronic proportional pressure reducing valve 700: Overload relief valve

Claims

Claim 1 An electro-hydraulic control valve comprising: a plurality of spool receiving portions formed parallel to each other; a plurality of first supply passages each connected to one side area of ​​the plurality of spool receiving portions; a plurality of second supply passages each connected to the other side area of ​​the plurality of spool receiving portions; a parallel passage formed in a direction intersecting the plurality of spool receiving portions and spaced apart from the plurality of spool receiving portions; and a plurality of connecting passages each connecting the parallel passages and the central area of ​​the plurality of spool receiving portions; a plurality of control spools each movably installed in the plurality of spool receiving portions to control the direction of movement of the hydraulic fluid according to positional movement; and a plurality of check valves each installed at the confluence point of the parallel passages and the plurality of connecting passages to restrict the movement of the hydraulic fluid in the direction of the parallel passages from the plurality of connecting passages, wherein the plurality of check valves are offset so as to be relatively adjacent to either of the plurality of first supply passages or the plurality of second supply passages, and the plurality of connecting passages are formed offset so as to be relatively adjacent to the other of the plurality of first supply passages or the plurality of second supply passages. Claim 2 In claim 1, the electro-hydraulic control valve further comprises a plurality of electro-proportional pressure reducing valves that regulate a pilot pressure applied to one end of the plurality of control spools in proportion to an input current signal. Claim 3 delete Claim 4 In claim 1, the valve body further comprises a plurality of relief valve coupling portions each connected to the plurality of first supply passages and the plurality of second supply passages, and the electro-hydraulic control valve further comprises an overload relief valve installed in each of the plurality of relief valve coupling portions to reduce peak pressure generated in the plurality of first supply passages and the plurality of second supply passages. Claim 5 An electro-hydraulic control valve according to claim 1, characterized in that each of the plurality of connecting passages includes an inclined section. Claim 6 An electro-hydraulic control valve according to claim 1, wherein the spool receiving portion has a length in the transverse direction of the valve body and a plurality of spools are arranged in two parallel rows along the longitudinal direction of the valve body. Claim 7 An electro-hydraulic control valve according to claim 6, wherein the first supply path, the second supply path, the connecting path, and the check valve are arranged in a plurality of rows along the longitudinal direction of the valve body, and the rows are symmetrical to each other. Claim 8 An electro-hydraulic control valve according to claim 1, wherein the spool receiving portion has a length in the transverse direction of the valve body and a plurality of them are arranged in a parallel row along the longitudinal direction of the valve body, and a pair of valve bodies are combined such that the first supply path, the second supply path, the connecting path, and the check valve are each symmetrical to each other.

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