A boom lifting height limiting system for a loader, the loader, and the method thereof.

Abstract

This invention discloses a boom lifting height limiting system for a loader, a loader, and a method thereof, which solves the problem of potential danger when the boom of a loader is lifted too high in the prior art, and has the beneficial effect of effectively limiting the boom lifting height. The specific solution is as follows: A boom lifting height limiting system for a loader includes a signal acquisition component, which is installed at the front frame and fixed to the front frame through an arc-shaped bracket. The arc-shaped bracket is fixed to the boom cylinder, and the arc-shaped bracket has an arc-shaped groove. The signal acquisition component is located in the arc-shaped groove and protrudes from the arc-shaped groove. During the boom lifting process, the boom cylinder drives the arc-shaped bracket to move relative to the signal acquisition component. When the boom cylinder is lifted to the limited position, the signal acquisition component can sense the boom cylinder and generate an electrical signal. An on / off valve is set in the pilot oil circuit of the boom cylinder. The signal acquisition component and the on / off valve are respectively connected to a controller.

Description

Technical Field

[0001] This invention relates to the field of boom lifting, and in particular to a boom lifting height limiting system for a loader, a loader, and a method thereof. Background Technology

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

[0003] Loaders are typically equipped with a maximum lifting height, for example, a 5-ton loader. (See reference...) Figure 1 As shown, its normal lifting height (including materials) is approximately 5892mm. The operator can adjust the lifting height of the boom through the pilot handle during operation. However, in some specific workplaces, such as under overpasses, inside workshops, and construction sites under high-voltage lines, lifting the boom too high can pose certain dangers. Relying solely on the operator's reference to the pilot handle to limit the boom lifting height is not timely or accurate, thus affecting the safety of normal operations.

[0004] Existing technologies also include lifting height control systems. For example, Chinese patent application CN202310794920.4, filed on June 30, 2023, discloses a lifting control system, method, and loader for a loader boom. However, these systems primarily control the lifting height through the control of the hydraulic system, which still relies on the driver's control and suffers from problems with insufficient timeliness and accuracy in response.

[0005] Some limit devices also have limit switches. For example, Chinese patent application CN201420204734.7, filed on April 25, 2014, discloses a lifting limit device for a loading boom, which uses a limit switch to provide feedback on the position of the boom, but it limits the position of the boom.

[0006] In summary, the existing technology of limiting the boom position presents the problem of inconvenience in setting limit switches due to the high boom height. Summary of the Invention

[0007] To address the shortcomings of existing technologies, the purpose of this invention is to provide a boom lifting height limiting system for a loader, which can effectively limit the boom lifting height.

[0008] To achieve the above objectives, the present invention is implemented through the following technical solution:

[0009] A boom lifting height limiting system for a loader includes a signal acquisition component, which is mounted on the front frame and fixed to the front frame via an arc-shaped bracket. The arc-shaped bracket is fixed to the boom cylinder, and the arc-shaped bracket has an arc-shaped groove. The signal acquisition component is located within the arc-shaped groove and protrudes from the arc-shaped groove. During boom lifting, the boom cylinder drives the arc-shaped bracket to move relative to the signal acquisition component. When the boom cylinder is lifted to the limited position, the signal acquisition component can sense the boom cylinder and generate an electrical signal.

[0010] The on / off valve is installed in the pilot oil circuit of the boom cylinder. The signal acquisition unit is interlocked with the on / off valve. When the on / off valve receives the electrical signal sent by the signal acquisition unit, the on / off valve reverses to cut off the pilot oil circuit.

[0011] As described above, in a loader boom lifting height limiting system, the sensing end of the signal acquisition component is positioned facing the side of the arc-shaped bracket. A protrusion is provided at one end of the arc-shaped bracket near the rodless chamber of the boom cylinder. The protrusion is positioned 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.

[0012] As described above, in a loader boom lifting height limiting system, an L-shaped positioning element is provided at one end of the arc-shaped bracket near the rodless chamber of the boom cylinder. The signal acquisition component senses the limited position of the boom cylinder by knowing the distance between its sensing end and one side of the L-shaped positioning element.

[0013] As described above, in a loader boom lifting height limiting system, one end of the arc-shaped bracket is detachably installed on the outer shell of the boom cylinder. The arc length of the arc groove is selected according to the application of the boom. The arc-shaped bracket is set along the moving path direction during the lifting process of the boom cylinder, and the arc-shaped bracket is set in a direction away from the boom.

[0014] The inner side of the arc-shaped bracket is spaced apart from the hinge seat of the front frame. The hinge seat is a hinge seat that is hinged to the boom cylinder. The center of the arc-shaped groove is set towards 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 end of the signal acquisition component away from the front frame is greater than the width of the arc groove, and the diameter of the middle part of the signal acquisition component is smaller than the width of the arc groove.

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

[0017] Secondly, the present invention provides a hydraulic control system for a loader, including a boom lifting height limiting system for a loader, wherein an oil tank is connected to a pilot valve and a multi-way directional valve, the pilot valve is connected to the multi-way directional valve, the multi-way directional 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 directional valve, and an on / off valve is provided between the pilot valve and the multi-way directional valve.

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

[0019] Thirdly, the present invention provides a loader, including a front frame, the front frame being hinged to the boom, a boom cylinder being disposed between the front frame and the boom, and the loader also being provided with the boom lifting height limiting system of the loader described above.

[0020] In the loader described above, the front frame is provided with an opening for installing the signal acquisition component, and the opening is located on one side of the mounting hole between the front frame and the boom cylinder.

[0021] Fourthly, the present invention also provides a method for limiting the boom lifting height of a loader, employing the aforementioned boom lifting height limiting system for a loader, comprising the following:

[0022] An on / off valve is installed 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 installed at the boom cylinder. The signal acquisition component passes through the arc-shaped groove of the arc-shaped bracket and is fixed to the front frame. The signal acquisition component is connected to the controller.

[0024] As the boom cylinder is lifted, the arc-shaped support moves relative to the signal acquisition component. When the boom cylinder is lifted to the specified position, the signal acquisition component can sense the boom cylinder, generate an electrical signal, and send it to the controller.

[0025] When the controller receives the electrical signal sent by the signal acquisition unit, it determines that the boom lifting height has reached the limit. The controller then controls the on-off valve to disconnect, cutting off the transmission of pilot oil. The boom valve core of the multi-way directional valve returns to the neutral position under the action of spring force, thereby limiting the continued lifting of the boom cylinder.

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

[0027] 1) In this invention, considering that the boom cylinder will rotate axially around the mounting hole between the front frame and the boom cylinder during the boom lifting process, an arc-shaped bracket is set at the boom cylinder. The arc-shaped bracket has an arc-shaped groove, so that the signal acquisition component passes through the arc-shaped groove and is fixed to the front frame. In this way, during the boom lifting process, the boom cylinder drives the arc-shaped bracket to move relative to the signal acquisition component. When the boom cylinder is lifted to a certain position, the signal acquisition component can sense the boom cylinder and generate an electrical signal, which is then sent to the controller. The controller controls the on / off valve to disconnect based on the electrical signal. The arc-shaped bracket is set by the rotation of the boom cylinder. The structure is reasonable, more flexible, easy to install, and the overall response is timely and accurate.

[0028] 2) In this invention, the sensing end of the signal acquisition component can cooperate with the protrusion at one end of the arc-shaped bracket. The signal acquisition component can sense the limited position of the boom cylinder by knowing the distance between its sensing end and the protrusion. Alternatively, an L-shaped positioning component is provided on one side of the arc-shaped bracket. The signal acquisition component can sense the limited position of the boom cylinder by knowing the distance between its sensing end and one side of the L-shaped positioning component. This ensures that the signal acquisition component accurately knows the position of the arc-shaped bracket.

[0029] 3) In this invention, the arc-shaped bracket can be detachably installed on the outer shell of the boom cylinder, which facilitates quick installation on site. In locations where there is no height restriction, the arc-shaped bracket can be detached. Multiple arc-shaped brackets can be provided. The appropriate arc length of the arc groove can be selected according to the application of the boom, that is, the appropriate arc-shaped bracket can be selected.

[0030] 4) The hydraulic control system in this invention has a reasonable structure. An on / off valve is set between the pilot valve and the multi-way directional valve. Under normal conditions, the on / off valve is kept open, and oil is supplied from the pilot valve to the boom valve core control chamber of the multi-way directional valve. When the signal acquisition component senses that the boom cylinder has reached the limit position, it sends an electrical signal to the controller. The controller switches the on / off valve to cut off the transmission of pilot oil to the multi-way directional valve, thereby limiting the lifting of the boom cylinder and limiting the lifting height of the loader. Attached Figure Description

[0031] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0032] Figure 1 This is a schematic diagram of the highest state of the boom when it is unrestricted in the existing technology.

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

[0034] Figure 3 This is a top view of an arc-shaped bracket with protrusions in a loader boom lifting height limiting system according to one or more embodiments of the present invention.

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

[0036] Figure 5 This 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 This is a schematic diagram of a proximity switch in a boom lifting height limit system of a loader according to one or more embodiments of the present invention.

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

[0039] The diagram exaggerates the spacing or dimensions between parts to show their positions; the diagram is for illustrative purposes only.

[0040] The components include: 1. boom, 2. boom cylinder, 3. front frame, 4. arc-shaped bracket, 5. arc-shaped groove, 6. mounting hole, 7. protrusion, 8. proximity switch, 9. L-shaped positioning component, 10. L-shaped proximity switch, 11. working pump, 12. pilot pump, 13. return oil filter, 14. multi-way directional valve, 15. bucket cylinder, 16. on / off valve, 17. pilot valve, and 18. selector valve. Detailed Implementation

[0041] It should be noted that the following detailed description is illustrative and intended to provide further explanation of the invention. Unless otherwise specified, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0042] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention. As used herein, unless otherwise expressly indicated by the invention, the singular form is also intended to include the plural form. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0043] As described in the background section, existing technologies have problems such as insufficient response time and inconvenient installation of the boom lifting limit device. In order to solve the above technical problems, this invention proposes a boom lifting height limit system for a loader.

[0044] Example 1

[0045] In a typical embodiment of the present invention, reference is made to Figure 2 As shown, a boom lifting height limiting system for a loader includes a signal acquisition component. The signal acquisition component is installed on the front frame 3 and is fixed to the front frame 3 through an arc-shaped bracket. The arc-shaped bracket is fixed to the boom cylinder 2. The arc-shaped bracket 4 is provided with an arc-shaped groove 5. The signal acquisition component is located in the arc-shaped groove 5 and protrudes from the arc-shaped groove 5. During the lifting of the boom 1, the boom cylinder 2 drives the arc-shaped bracket 4 to move relative to the signal acquisition component. When the boom cylinder is lifted to the limited position, the signal acquisition component can sense the boom cylinder and generate an electrical signal.

[0046] On / off valve 16 is installed in the pilot oil circuit of 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 reverses to cut off the pilot oil circuit.

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

[0048] Additionally, refer to Figure 6 As shown, the signal acquisition component can use an existing proximity switch 8.

[0049] In this embodiment, the diameter of the end of the signal acquisition component away from the front frame 3 is greater than the width of the arc groove 5, and the diameter of the middle part of the signal acquisition component is smaller than the width of the arc groove 5. This not only facilitates the installation of the signal acquisition component, but also effectively prevents the signal acquisition component from detaching from the arc groove 5.

[0050] It is easy to understand that the arc-shaped bracket 4 is arc-shaped overall, and the arc-shaped bracket 4 is spaced apart from the front frame 3. To prevent the signal acquisition component from coming out of the arc-shaped groove, the signal acquisition component is set to protrude from the arc-shaped groove, as shown in the reference. Figure 3 As shown, the sensing end of the signal acquisition component is positioned facing the side of the arc-shaped bracket 4, meaning that the end of the signal acquisition component furthest from the front frame is L-shaped, thus forming an L-shaped proximity switch 10 (see reference). Figure 4 As shown), the L-type proximity switch refers to the proximity switch whose detection end is set towards the protrusion 7. However, the main body of the L-type proximity switch is still fixed to the front frame 3 through the arc groove. The arc bracket 4 is provided with the protrusion 7 at one end near the rodless cavity of the boom cylinder. The protrusion 7 is set 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 can sense the limited position of the boom cylinder 2 by knowing the distance between its sensing end and the protrusion 7.

[0051] In other examples, refer to Figure 5As shown, an L-shaped positioning element 9 is provided at one end of the arc-shaped bracket 4 near the rodless cavity of the boom cylinder. One end of the L-shaped positioning element 9 is fixedly connected to the arc-shaped bracket 4, and the other side of the L-shaped positioning element 9 is spaced apart from the arc-shaped bracket 4. During the movement of the arc-shaped bracket 4 with the boom cylinder, the signal acquisition component senses the limited position of the boom cylinder 2 by knowing the distance between its sensing end and one side of the L-shaped positioning element 9 (the side of the L-shaped positioning element 9 away from the arc-shaped bracket 4).

[0052] Specifically, one end of the arc-shaped bracket 4 is detachably installed on the outer shell of the boom cylinder 2. The arc-shaped bracket is fixed to one end of the rodless cavity of the boom cylinder 2, rather than the telescopic end. The outer shell of the boom cylinder 2 is equipped with a mounting seat during the manufacturing process. One end of the arc-shaped 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, while also being easy to disassemble.

[0053] It should be noted that the arc-shaped bracket 4 is set along the moving path direction during the lifting process of the boom cylinder, and the arc-shaped bracket 4 is set in a direction away from the boom; the inner side of the arc-shaped bracket 4 is spaced apart from the hinge seat of the front frame, the hinge seat is the hinge seat that is hinged to the boom cylinder, the center of the arc-shaped groove is set 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 multiple arc-shaped supports 4 can be set, and the length of the arc groove of different arc-shaped supports is different. The arc length of the arc groove is selected according to the application of the boom.

[0055] The height limiting system provided in this embodiment involves the boom cylinder rotating around the axis of the front frame and the boom cylinder mounting hole during boom lifting. When the boom cylinder is lifted to the limited position, i.e., when the proximity switch senses the boom cylinder, an electrical signal is generated. A switch valve is connected in series in the pilot oil line that controls the extension of the boom cylinder. Under the action of the spring force, the pilot oil is supplied normally. When the proximity switch senses the boom cylinder, the electrical signal is transmitted to the non-spring chamber of the switch valve, which controls the valve core of the switch valve to switch direction, cutting off the transmission of pilot oil to the boom valve core in the multi-way directional valve, thereby limiting the lifting of the boom cylinder and limiting the lifting height of the entire machine.

[0056] Example 2

[0057] This embodiment provides a hydraulic control system for a loader, referencing... Figure 7As shown, the boom lifting height limiting system of a loader as described in Embodiment 1 includes an oil tank connected to a pilot valve 17 and a multi-way directional valve 14. The multi-way directional valve is an existing multi-way directional valve, and the pilot valve 17 is also an existing pilot valve. The pilot valve 17 is connected to the multi-way directional valve 14, and the multi-way directional 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 directional valve to realize the reversal of the boom valve core. An on / off valve 16 is provided between the pilot valve 17 and the multi-way directional valve.

[0058] Among them, the pilot valve 17 is connected to the oil tank by a selector valve 18. The oil tank is connected to the multi-way directional valve through the working pump 11 and to the selector valve 18 through the pilot pump 12. In addition, the oil tank is equipped with a return oil filter 13.

[0059] It should be noted that multi-way directional valves and selector valves are common existing valves and will not be described in detail.

[0060] Example 3

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

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

[0063] Example 4

[0064] This embodiment provides a method for limiting the boom lifting height of a loader, employing the boom lifting height limiting system for a loader described in Embodiment 1, and includes the following:

[0065] An on / off valve is installed 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 installed at the boom cylinder. The signal acquisition component passes through the arc-shaped groove of the arc-shaped bracket and is fixed to the front frame. The signal acquisition component is connected to the controller.

[0067] As the boom cylinder is lifted, the arc-shaped support moves relative to the signal acquisition component. When the boom cylinder is lifted to the specified position, the signal acquisition component can sense the boom cylinder, generate an electrical signal, and send it to the controller.

[0068] When the controller receives the electrical signal sent by the signal acquisition unit, it determines that the boom lifting height has reached the limit. The controller then controls the on-off valve to open, cutting off the transmission of pilot oil to the boom valve core of the multi-way directional valve. Under the action of the spring force, the boom valve core of the multi-way directional valve returns to the neutral position, thereby limiting the continued lifting of the boom cylinder.

[0069] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A boom lifting height limiting system for a loader, characterized in that, include: The signal acquisition component is installed on the front frame and fixed to the front frame through an arc-shaped bracket. The arc-shaped bracket is fixed to the boom cylinder and has an arc-shaped groove. The signal acquisition component is located in the arc-shaped groove and protrudes from the arc-shaped groove. During boom lifting, the boom cylinder drives the arc-shaped bracket to move relative to the signal acquisition component. When the boom cylinder is lifted to a certain position, the signal acquisition component can sense the boom cylinder and generate an electrical signal. On / off valve, which is installed in the pilot oil circuit of the boom cylinder; The signal acquisition unit is interlocked with the on / off valve. When the on / off valve receives the electrical signal sent by the signal acquisition unit, it reverses to cut off the pilot oil circuit.

2. The boom lifting height limiting system for a loader according to claim 1, characterized in that, The sensing end of the signal acquisition component is positioned facing one side of the arc-shaped bracket. A protrusion is provided at one end of the arc-shaped bracket near the rodless cavity of the boom cylinder. The protrusion is positioned opposite to the sensing end of the signal acquisition component. The signal acquisition component can sense the defined position of the boom cylinder by knowing the distance between its sensing end and the protrusion.

3. The boom lifting height limiting system for a loader according to claim 1, characterized in that, An L-shaped positioning element is provided at one end of the arc-shaped bracket near the rodless cavity of the boom cylinder. The signal acquisition component senses the defined position of the boom cylinder by knowing the distance between its sensing end and one side of the L-shaped positioning element.

4. The boom lifting height limiting system for a loader according to claim 1, characterized in that, One end of the arc-shaped bracket can be detachably installed on the outer shell of the boom cylinder. The arc length of the arc groove is selected according to the application of the boom. The arc-shaped bracket is set along the moving path direction during the lifting process of the boom cylinder, and the arc-shaped bracket is set in a direction away from the boom. The inner side of the arc-shaped bracket is spaced apart from the hinge seat of the front frame. The hinge seat is a hinge seat that is hinged to the boom cylinder. The center of the arc-shaped groove is set towards the assembly hole of the front frame and the boom cylinder.

5. A boom lifting height limiting system for a loader according to claim 1, characterized in that, The diameter of the signal acquisition component at the end furthest from the front frame is greater than the width of the arc-shaped groove, and the diameter of the middle part of the signal acquisition component is smaller than the width of the arc-shaped groove. The signal acquisition component is a proximity switch.

6. A hydraulic control system for a loader, characterized in that, The loader boom lifting height limiting system according to any one of claims 1-5 includes an oil tank connected to a pilot valve and a multi-way directional valve, the pilot valve being connected to the multi-way directional valve, the multi-way directional valve being connected to the bucket cylinder and the boom cylinder respectively, the pilot valve being used to supply oil to the boom valve core of the multi-way directional valve, and an on / off valve being provided between the pilot valve and the multi-way directional valve.

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

8. A loader, characterized in that, The loader includes a front frame, which is hinged to the boom, and a boom cylinder is provided between the front frame and the boom. The loader is also provided with a boom lifting height limiting system of any one of claims 1-5.

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

10. A method for limiting the boom lifting height of a loader, characterized in that, The boom lifting height limiting system of a loader according to any one of claims 1-5 includes the following: An on / off valve is installed in the pilot oil circuit of the boom cylinder, and the on / off valve is connected to the controller; An arc-shaped bracket is installed at the boom cylinder. The signal acquisition component passes through the arc-shaped groove of the arc-shaped bracket and is fixed to the front frame. The signal acquisition component is connected to the controller. As the boom cylinder is lifted, the arc-shaped support moves relative to the signal acquisition component. When the boom cylinder is lifted to the specified position, the signal acquisition component can sense the boom cylinder, generate an electrical signal, and send it to the controller. When the controller receives the electrical signal from the signal acquisition unit, it determines that the boom lifting height has reached the limit. The controller then controls the on / off valve to disconnect, cutting off the transmission of pilot oil and thus limiting the continued lifting of the boom cylinder.

Images