Movable arm lifting height limiting system of loading machine, loading machine and method

Abstract

The invention discloses a movable arm lifting height limiting system of a loading machine, the loading machine and a method, solves the problem that certain danger exists when a movable arm of the loading machine lifts too high in the prior art, and has the beneficial effect of effectively limiting the lifting height of the movable arm. Comprising a signal acquisition component, the signal acquisition component is installed on a front frame, the signal acquisition component penetrates through an arc-shaped support to be fixed to the front frame, the arc-shaped support is fixed to a movable arm oil cylinder, the arc-shaped support is provided with an arc-shaped groove, and the signal acquisition component is located in the arc-shaped groove and protrudes out of the arc-shaped groove. In the lifting process of the movable arm, the movable arm oil cylinder drives the arc-shaped support to move relative to the signal collecting component, and when the movable arm oil cylinder is lifted to a limited position, the signal collecting component can sense the movable arm oil cylinder and generate an electric signal; the on-off valve is arranged in a pilot oil way of the boom cylinder; and the signal acquisition part and the on-off valve are respectively connected with the controller.

Description

Technical Field

[0001] The invention relates to the field of boom lifting, and in particular to a boom lifting height limiting system of a loader, a loader and a method. Background Art

[0002] The statements in this section merely provide background information related to the present invention and do not necessarily constitute prior art.

[0003] Loaders are usually set with a maximum lift height. For example, for a 5t loader, refer to Figure 1 As shown, its normal lifting height (including materials) is about 5892mm. The driver can adjust the lifting height of the boom through the pilot handle during work; but in some specific workplaces, such as under viaducts, in workshops, under high-voltage lines and other construction sites, lifting the boom too high will bring certain dangers. The height limit of the boom lifting that only relies on the driver to refer to the pilot handle is not timely and accurate, which affects the safety of normal operations.

[0004] Lifting height control systems are also designed in the prior art. For example, Chinese patent application CN202310794920.4, with an application date of June 30, 2023, discloses a loader boom lifting control system, method and loader, but the lifting height is mainly controlled by controlling the oil circuit, and still relies on the control of the driver, and there is a problem of insufficient timely and accurate response.

[0005] There are also limit devices with limit switches. For example, Chinese patent application CN201420204734.7, filed on April 25, 2014, discloses a loader boom lifting limit device, which provides feedback on the position of the boom through the limit switch, but it limits the position of the boom.

[0006] In summary, in the prior art, the position of the boom is limited, but due to the high height of the boom, it is inconvenient to set a limit switch. Summary of the invention

[0007] In view of the deficiencies in the prior art, an object of the present invention is to provide a boom lifting height limiting system for a loader, which can effectively limit the boom lifting height.

[0008] In order to achieve the above object, the present invention is implemented through the following technical solutions:

[0009] A boom lifting height limiting system for a loader includes a signal collection component, the signal collection component is installed at a front frame, the signal collection component passes through an arc bracket and is fixed at the front frame, the arc bracket is fixed to a boom oil cylinder, the arc bracket is provided with an arc groove, the signal collection component is located in the arc groove, the signal collection component protrudes from the arc groove, during the boom lifting process, the boom oil cylinder drives the arc bracket to move relative to the signal collection component, and when the boom oil cylinder is lifted to a limited position, the signal collection component can sense the boom oil cylinder and generate an electrical signal;

[0010] The on-off valve is arranged in the pilot oil circuit of the boom cylinder. The signal acquisition component is interlocked with the on-off valve. When the on-off valve receives the electrical signal sent by the signal acquisition component, the on-off valve is switched to cut off the pilot oil circuit.

[0011] In the boom lifting height limiting system of a loader as described above, the sensing end of the signal acquisition component is arranged toward one side of the arc-shaped bracket, and a protrusion is arranged at one end of the arc-shaped bracket close to the rodless chamber of the boom cylinder. The protrusion is arranged opposite to the sensing end of the signal acquisition component, and the signal acquisition component senses the limited position of the boom cylinder by obtaining the distance between its sensing end and the protrusion.

[0012] In the boom lifting height limiting system of a loader as described above, an L-shaped positioning piece is provided at one end of the arc-shaped bracket close to the rodless chamber of the boom cylinder, and the signal acquisition component senses the limited position of the boom cylinder by obtaining the distance between its sensing end and one side of the L-shaped positioning piece.

[0013] In the above-mentioned boom lifting height limiting system for a loader, one end of the arc bracket is detachably mounted on the outer shell of the boom cylinder, the arc length of the arc groove is selected according to the use location of the boom, the arc bracket is arranged along the moving path direction of the boom cylinder during lifting, and the arc bracket is arranged in a direction away from the boom;

[0014] The inner side surface of the arc-shaped bracket is spaced apart from the hinge seat of the front frame, the hinge seat is hingedly connected to the boom cylinder, and the center of the arc-shaped groove is arranged toward the direction of the assembly hole of the front frame and the boom cylinder.

[0015] In the boom lifting height limiting system of a loader as described above, the diameter of the signal collection component at the end away from the front frame is greater than the width of the arc-shaped groove, and the diameter of the middle part of the signal collection component is smaller than the width of the arc-shaped groove;

[0016] The signal collection component is a proximity switch.

[0017] In the second aspect, the present invention provides a hydraulic control system of a loader, including a boom lifting height limit system of the loader, wherein the oil tank is connected to a pilot valve and a multi-way reversing valve, the pilot valve is connected to the multi-way reversing valve, the multi-way reversing valve is connected to the bucket cylinder and the boom cylinder respectively, the pilot valve is used to supply oil to the boom valve core control chamber of the multi-way reversing valve, and an on-off valve is arranged between the pilot valve and the multi-way reversing valve.

[0018] In the hydraulic control system of a loader as described above, a selection valve is further connected between the pilot valve and the oil tank.

[0019] In a third aspect, the present invention provides a loader, comprising a front frame, the front frame being hingedly connected to a boom, a boom cylinder being arranged between the front frame and the boom, and the loader is also provided with the boom lifting height limiting system of the loader.

[0020] In the loader as described above, the front frame is provided with an opening, the opening is used to install the signal acquisition component, and the opening is located on one side of the assembly hole of the front frame and the boom cylinder.

[0021] In a fourth aspect, the present invention further provides a method for limiting the lifting height of a loader's boom, which uses the aforementioned method for limiting the lifting height of a loader's boom, and includes the following contents:

[0022] An on-off valve is arranged in the pilot oil circuit of the boom cylinder, and the on-off valve is connected to the controller;

[0023] An arc-shaped bracket is arranged at the boom cylinder, a signal collection component is fixed at the front frame through an arc-shaped slot of the arc-shaped bracket, and the signal collection component is connected to the controller;

[0024] As the boom cylinder is lifted, the arc bracket moves relative to the signal collection component. When the boom cylinder is lifted to a limited position, the signal collection component can sense the boom cylinder, generate an electrical signal and send it to the controller.

[0025] The controller receives the electrical signal sent by the signal acquisition component and determines that the boom lifting height has reached the limit stop. The controller controls the on-off valve to disconnect, cuts off the transmission of the pilot oil, and the boom valve core of the multi-way reversing valve returns to the middle position under the action of the spring force, thereby limiting the continued lifting of the boom cylinder.

[0026] The beneficial effects of the present invention are as follows:

[0027] 1) The present invention takes into account that the boom cylinder will rotate axially around the assembly hole between the front frame and the boom cylinder during the process of pushing the boom to lift. Therefore, an arc bracket is provided at the boom cylinder, and an arc groove is provided on the arc bracket, so that the signal collection component is fixed to the front frame through the arc groove. In this way, during the boom lifting process, the boom cylinder drives the arc bracket to move relative to the signal collection component. When the boom cylinder is lifted to a limited position, the signal collection component can sense the boom cylinder and generate an electrical signal, which is sent to the controller. The controller controls the on-off valve to disconnect according to the electrical signal. The arc bracket is provided by utilizing the rotation of the boom cylinder. The structural setting is reasonable, more flexible, and convenient to install. The overall response is timely and the accuracy is high.

[0028] 2) The sensing end of the signal acquisition component in the present invention can cooperate with the protrusion at one end of the arc-shaped bracket, and the signal acquisition component senses the limited position of the boom cylinder by obtaining the distance between the sensing end and the protrusion. Alternatively, an L-shaped positioning piece is provided on one side of the arc-shaped bracket, and the signal acquisition component senses the limited position of the boom cylinder by obtaining the distance between the sensing end and one side of the L-shaped positioning piece, thereby ensuring that the signal acquisition component accurately knows the position of the arc-shaped bracket.

[0029] 3) The arc bracket in the present invention can be detachably installed on the outer shell of the boom cylinder, which is convenient for quick installation on site. In a position where there is no height restriction, the arc bracket can be detachable. Multiple arc brackets can be provided. An arc groove with a suitable arc length is selected according to the place where the boom is used, that is, a suitable arc bracket is selected.

[0030] 4) The hydraulic control system of the present invention has a reasonable structure. An on-off valve is arranged between the pilot valve and the multi-way reversing valve. Under normal circumstances, the on-off valve remains open, and the pilot valve supplies oil to the boom valve core control chamber of the multi-way reversing valve. When the signal acquisition component senses that the position of the boom cylinder reaches a limited position, it sends an electrical signal to the controller. The controller switches the on-off valve to cut off the transmission of the pilot oil to the multi-way reversing valve, thereby limiting the lifting of the boom cylinder and limiting the lifting height of the loader. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The accompanying drawings in the specification, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0032] Figure 1 It is a schematic diagram of the highest state when the boom is not restricted in the prior art.

[0033] Figure 2 It is a schematic diagram of boom lifting when restricted by an arc-shaped bracket in a boom lifting height limiting system of a loader according to one or more embodiments of the present invention.

[0034] Figure 3 It is a top view of a curved bracket provided with a protrusion in a boom lifting height limiting system of a loader according to one or more embodiments of the present invention.

[0035] Figure 4 It is a front view of an L-shaped proximity switch in a boom lifting height limiting system of a loader according to one or more embodiments of the present invention.

[0036] Figure 5 It is a schematic diagram of an L-shaped positioning block in a boom lifting height limiting system of a loader according to one or more embodiments of the present invention.

[0037] Figure 6 It is a schematic diagram of a proximity switch in a boom lifting height limiting system of a loader according to one or more embodiments of the present invention.

[0038] Figure 7 The diagram is a schematic diagram of a hydraulic control system of a loader according to one or more embodiments of the present invention.

[0039] In the figure: the distances or sizes between parts are exaggerated to show the positions of various parts, and the schematic diagram is for reference only.

[0040] Among them: 1. Boom, 2. Boom cylinder, 3. Front frame, 4. Arc bracket, 5. Arc groove, 6. Mounting hole, 7. Bump, 8. Proximity switch, 9. L-type positioning piece, 10. L-type proximity switch, 11. Working pump, 12. Pilot pump, 13. Return oil filter, 14. Multi-way reversing valve, 15. Bucket cylinder, 16. On-off valve, 17. Pilot valve, 18. Selection valve. DETAILED DESCRIPTION

[0041] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used in the present invention have the same meanings as those commonly understood by those skilled in the art to which the present invention belongs.

[0042] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present invention. As used herein, unless otherwise explicitly stated in the present invention, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "include" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof;

[0043] As introduced in the background technology, the boom lifting limit in the prior art has the problems of insufficient response and inconvenient installation of the limit device. In order to solve the above technical problems, the present invention proposes a boom lifting height limit system for a loader.

[0044] Embodiment 1

[0045] In a typical embodiment of the present invention, reference is made to Figure 2 As shown, a boom lifting height limiting system of a loader includes a signal collection component, which is installed at a front frame 3, and the signal collection component is fixed at the front frame 3 through an arc bracket, and the arc bracket is fixed to a boom cylinder 2, and an arc slot 5 is provided on the arc bracket 4, and the signal collection component is located in the arc slot 5, and the signal collection component is protruded from the arc slot 5. During the lifting process of the boom 1, the boom cylinder 2 drives the arc bracket 4 to move relative to the signal collection component, and when the boom cylinder is lifted to a limited position, the signal collection component can sense the boom cylinder and generate an electrical signal;

[0046] The on-off valve 16 is arranged in the pilot oil circuit of the boom cylinder. The signal acquisition component is interlocked with the on-off valve. When the on-off valve 16 receives the electrical signal sent by the signal acquisition component, the on-off valve is switched to cut off the pilot oil circuit.

[0047] The on-off valve is an existing reversible solenoid valve, and the on-off valve is connected in series in the pilot oil circuit.

[0048] In addition, refer to Figure 6 As shown, the signal collection component can adopt the existing proximity switch 8.

[0049] In this embodiment, the diameter of the end of the signal collection component away from the front frame 3 is larger than the width of the arc groove 5, and the diameter of the middle part of the signal collection component is smaller than the width of the arc groove 5, which not only facilitates the installation of the signal collection component, but also effectively prevents the signal collection component from being separated from the arc groove 5;

[0050] It is easy to understand that the arc bracket 4 is an arc-shaped as a whole, and the arc bracket 4 is set at a distance from the front frame 3. In order to prevent the signal collection component from escaping from the arc groove, the signal collection component protrudes from the arc groove. Figure 3 As shown, the sensing end of the signal acquisition component is arranged toward one side of the arc-shaped bracket 4, that is, at this time, the end of the signal acquisition component away from the front frame is L-shaped, that is, an L-shaped proximity switch 10 is formed (reference Figure 4 As shown), the L-type proximity switch refers to a proximity switch whose detection end is arranged toward the direction of the protrusion 7, but the main body of the L-type proximity switch is still fixed to the front frame 3 through the arc groove, and a protrusion 7 is arranged at one end of the arc bracket 4 close to the rodless cavity of the boom cylinder, and the protrusion 7 is arranged opposite to the sensing end of the signal acquisition component. In this way, when the boom cylinder drives the arc bracket 4 to move, the signal acquisition component senses the limited position of the boom cylinder 2 by knowing the distance between its sensing end and the protrusion 7.

[0051] In other examples, reference Figure 5As shown, an L-shaped positioning member 9 is provided at one end of the arc bracket 4 close to the rodless chamber of the boom cylinder, one end of the L-shaped positioning member 9 is fixedly connected to the arc bracket 4, and the other side of the L-shaped positioning member 9 is spaced apart from the arc bracket 4. When the arc bracket 4 moves with the boom cylinder, the signal acquisition component senses the limited position of the boom cylinder 2 by obtaining the distance between its sensing end and one side of the L-shaped positioning member 9 (the side of the L-shaped positioning member 9 away from the arc bracket 4).

[0052] Specifically, one end of the arc bracket 4 is detachably mounted on the outer shell of the boom cylinder 2, and the arc bracket is fixed to one end of the rodless chamber of the boom cylinder 2, rather than the telescopic end. The outer shell of the boom cylinder 2 is provided with a mounting seat during the manufacturing process, and one end of the arc bracket 4 is provided with a mounting hole 6. The mounting hole 6 is detachably connected to the mounting seat and can be quickly connected by bolts, and is convenient for disassembly.

[0053] It should be noted that the arc-shaped bracket 4 is arranged along the direction of the moving path during the lifting process of the boom cylinder, and the arc-shaped bracket 4 is arranged in the direction away from the boom; the inner side of the arc-shaped bracket 4 is arranged at a distance from the hinge seat of the front frame, and the hinge seat is an hinge seat hingedly connected to the boom cylinder. The center of the arc groove is arranged in the direction of the assembly hole of the front frame and the boom cylinder, and the center of the arc-shaped bracket is located in the axial direction of the assembly hole of the front frame and the boom cylinder.

[0054] It is easy to understand that there can be multiple arc-shaped brackets 4, and the lengths of the arc-shaped slots of different arc-shaped brackets are different. The arc length of the arc-shaped slot is selected according to the use location of the boom;

[0055] The height limiting system provided in this embodiment has the following characteristics: during the boom lifting process, the boom cylinder will rotate around the axis direction of the front frame and the boom cylinder assembly hole; when the boom cylinder is lifted to a limited position, that is, when the proximity switch senses the boom cylinder, an electrical signal is generated, and an on-off valve is connected in series to the pilot oil circuit for controlling the extension of the boom cylinder; under the action of the spring force, the pilot oil is normally supplied to the on-off valve; when the proximity switch senses the boom cylinder, an electrical signal is transmitted to the on-off valve non-spring chamber, which controls the on-off valve spool to switch direction, and cuts off the transmission of the pilot oil to the boom spool in the multi-way reversing valve, thereby limiting the lifting of the boom cylinder and limiting the lifting height of the entire machine;

[0056] Embodiment 2

[0057] This embodiment provides a hydraulic control system for a loader, referring to Figure 7As shown, it includes a boom lifting height limit system of a loader as described in Example 1, the oil tank is connected to the pilot valve 17 and the multi-way reversing valve 14, the multi-way reversing valve is an existing multi-way reversing valve, the pilot valve 17 is also an existing pilot valve, the pilot valve 17 is connected to the multi-way reversing valve 14, the multi-way reversing valve 14 is connected to the bucket cylinder 15 and the boom cylinder respectively, the pilot valve 17 is used to supply oil to the control end of the boom valve core in the multi-way reversing valve to realize the reversal of the boom valve core, and an on-off valve 16 is arranged between the pilot valve 17 and the multi-way reversing valve.

[0058] Among them, a selection valve 18 is also connected between the pilot valve 17 and the oil tank. The oil tank is connected to the multi-way reversing valve through the working pump 11, and is connected to the selection valve 18 through the pilot pump 12. In addition, a return oil filter 13 is arranged at the oil tank.

[0059] It should be noted that the multi-way reversing valve and the selection valve are both existing common valves and will not be described in detail.

[0060] Embodiment 3

[0061] This embodiment provides a loader, including a front frame 3, which is hingedly connected to a boom 1, and a boom cylinder 2 is arranged between the front frame 3 and the boom 1. The loader is also provided with a boom lifting height limiting system of a loader as described in Embodiment 1.

[0062] Specifically, the front frame 3 is provided with an opening, which may be a through hole, the size of which matches the size of the signal acquisition component mounting section, the opening is used to mount the signal acquisition component, and the opening is located on one side of the front frame and the boom cylinder assembly hole.

[0063] Embodiment 4

[0064] This embodiment provides a method for limiting the lifting height of a loader's boom, using a loader's boom lifting height limiting system described in Embodiment 1, including the following contents:

[0065] An on-off valve is arranged in the pilot oil circuit of the boom cylinder, and the on-off valve is connected to the controller;

[0066] An arc-shaped bracket is arranged at the boom cylinder, a signal collection component is fixed at the front frame through an arc-shaped slot of the arc-shaped bracket, and the signal collection component is connected to the controller;

[0067] As the boom cylinder is lifted, the arc bracket moves relative to the signal collection component. When the boom cylinder is lifted to a limited position, the signal collection component can sense the boom cylinder, generate an electrical signal and send it to the controller.

[0068] The controller receives the electrical signal sent by the signal acquisition component and determines that the boom lifting height has reached the limit stop. The controller controls the on-off valve to disconnect, cuts off the transmission of the pilot oil to the boom valve core of the multi-way reversing valve, and the boom valve core of the multi-way reversing valve returns to the middle position under the action of the spring force, thereby limiting the continued lifting of the boom cylinder.

[0069] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A lifting height limit system for a loader's boom, characterized in that: include: A signal collection component is installed on the front frame. The signal collection component passes through an arc bracket and is fixed on the front frame. The arc bracket is fixed to the boom cylinder. The arc bracket is provided with an arc groove. The signal collection component is located in the arc groove. The signal collection component protrudes from the arc groove. During the boom lifting process, the boom cylinder drives the arc bracket to move relative to the signal collection component. When the boom cylinder is lifted to a limited position, the signal collection component can sense the boom cylinder and generate an electrical signal. On-off valve, which is arranged in the pilot oil circuit of the boom cylinder; The signal acquisition component is interlocked with the on-off valve. When the on-off valve receives the electrical signal sent by the signal acquisition component, the on-off valve switches direction to cut off the pilot oil circuit.

2. The boom lifting height limiting system of a loader according to claim 1, characterized in that: The sensing end of the signal acquisition component is arranged toward one side of the arc bracket, and a protrusion is arranged at one end of the arc bracket close to the rodless chamber of the boom cylinder. The protrusion is arranged opposite to the sensing end of the signal acquisition component. The signal acquisition component senses the limited position of the boom cylinder by knowing the distance between its sensing end and the protrusion.

3. The boom lifting height limiting system of a loader according to claim 1, characterized in that: An L-shaped positioning piece is arranged at one end of the arc-shaped bracket close to the rodless cavity of the boom cylinder, and the signal acquisition component senses the limited position of the boom cylinder by obtaining the distance between its sensing end and one side of the L-shaped positioning piece.

4. The boom lifting height limiting system of a loader according to claim 1, characterized in that: One end of the arc bracket is detachably mounted on the outer shell of the boom cylinder, the arc length of the arc groove is selected according to the use location of the boom, the arc bracket is arranged along the moving path direction of the boom cylinder during lifting, and the arc bracket is arranged in a direction away from the boom; The inner side surface of the arc-shaped bracket is spaced apart from the hinge seat of the front frame, the hinge seat is hingedly connected to the boom cylinder, and the center of the arc-shaped groove is arranged toward the direction of the assembly hole of the front frame and the boom cylinder.

5. The boom lifting height limiting system of a loader according to claim 1, characterized in that: The diameter of the signal collection component at one end away from the front frame is larger than the width of the arc-shaped groove, and the diameter of the middle part of the signal collection component is smaller than the width of the arc-shaped groove; The signal collection component is a proximity switch.

6. A hydraulic control system for a loader, characterized in that: A boom lifting height limit system for a loader comprising the following: an oil tank connected to a pilot valve and a multi-way reversing valve, the pilot valve is connected to the multi-way reversing valve, the multi-way reversing valve is connected to a bucket cylinder and a boom cylinder respectively, the pilot valve is used to supply oil to a boom valve core of the multi-way reversing valve, and an on-off valve is arranged between the pilot valve and the multi-way reversing valve.

7. The hydraulic control system of a loader according to claim 6, characterized in that: A selection valve is also connected between the pilot valve and the oil tank.

8. A loader, characterized in that: The loader comprises a front frame which is hingedly connected to a boom, a boom cylinder being arranged between the front frame and the boom, and a boom lifting height limiting system of a loader according to any one of claims 1 to 5.

9. A loader according to claim 8, characterized in that: The front frame is provided with an opening, and the opening is used to install the signal acquisition component, and the opening is located on one side of the assembly hole of the front frame and the boom cylinder.

10. A method for limiting the lifting height of a loader's boom, characterized in that: A boom lifting height limiting system for a loader according to any one of claims 1 to 5 comprises the following contents: An on-off valve is arranged in the pilot oil circuit of the boom cylinder, and the on-off valve is connected to the controller; An arc-shaped bracket is arranged at the boom cylinder, a signal collection component is fixed at the front frame through an arc-shaped slot of the arc-shaped bracket, and the signal collection component is connected to the controller; As the boom cylinder is lifted, the arc bracket moves relative to the signal collection component. When the boom cylinder is lifted to a limited position, the signal collection component can sense the boom cylinder, generate an electrical signal and send it to the controller. The controller receives the electrical signal sent by the signal acquisition component and determines that the lifting height of the boom has reached the limit stop. The controller controls the on-off valve to disconnect and cut off the transmission of the pilot oil, thereby limiting the continued lifting of the boom cylinder.

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