Shearing apparatus and shearing method

Abstract

This disclosure relates to a shearing device and a shearing method. The shearing device includes a support, a first blade, a second blade, a drive device, a reversing valve assembly, and a control system. The first blade is mounted on the support, and the second blade is movably mounted on the support. The drive device is drivenly connected to the second blade and configured to drive the second blade to move relative to the first blade to complete the shearing action. The reversing valve assembly is configured to change the driving direction of the drive device to cause the second blade to reciprocate. The control system is configured to control the reversing of the reversing valve assembly and to enable the second blade to have a first working mode and a second working mode. In the first working mode, the stroke of the second blade relative to the first blade is fixed; in the second working mode, the stroke of the second blade relative to the first blade is variable, and the maximum stroke of the second blade in the second working mode is less than or equal to the stroke of the second blade in the first working mode.

Description

Technical Field

[0001] This disclosure relates to the field of engineering machinery technology, and in particular to a shearing device and shearing method. Background Technology

[0002] As people become more aware of protecting the ecological environment, tree planting is not only expanding in area but also becoming more standardized, from cities to rural areas. To ensure the healthy and orderly growth of trees, staff members prune them at specific times.

[0003] Currently, pruning tools are either ordinary pruning pliers or makeshift pruning tools assembled by attaching a blade to the top of an insulated operating rod. These pruning tools have low working force, a small working area, high labor intensity for workers, and low work efficiency.

[0004] To address these issues, hedge trimmers have emerged on the market, which can increase the working area and improve trimming efficiency to some extent. However, when trimming dense shrubs with thick branches, they often fail to cut through the branches, causing the blades to get stuck. In this situation, the hydraulic cylinder of the hedge trimmer is obstructed by the branches, causing its movement to stop. The hydraulic cylinder does not reach the reversing position and cannot trigger the hydraulic reversing valve, resulting in a halt to the trimming operation, affecting construction efficiency, and in severe cases, even damaging the shears and reducing the lifespan of the hedge trimmer.

[0005] It should be noted that the information disclosed in the background section of this disclosure is intended only to enhance the understanding of the overall background of this disclosure, and should not be construed as an admission or implication in any way that such information constitutes prior art known to those skilled in the art. The foregoing statements are only intended to provide background information in relation to this application and do not necessarily constitute prior art. Summary of the Invention

[0006] This disclosure provides a shearing device and a shearing method that can effectively improve shearing efficiency.

[0007] According to one aspect of this disclosure, a shearing device is provided, comprising:

[0008] support;

[0009] The first blade is mounted on the support.

[0010] The second blade is movably mounted on the bracket;

[0011] A drive unit is connected to the second blade and is configured to drive the second blade to move relative to the first blade to complete the shearing action.

[0012] The reversing valve assembly is configured to change the drive direction of the drive unit to cause the second blade to reciprocate; and

[0013] The control system is configured to control the switching of the directional valve assembly, and the control system is configured to give the second blade a first operating mode and a second operating mode, wherein in the first operating mode the movement stroke of the second blade relative to the first blade is fixed; in the second operating mode the movement stroke of the second blade relative to the first blade is variable, and the maximum movement stroke of the second blade in the second operating mode is less than or equal to the movement stroke of the second blade in the first operating mode.

[0014] In some embodiments, the control system includes a first automatic switching mechanism configured to enable automatic switching of the second blade between a first operating mode and a second operating mode, and to enable automatic reversing of the reversing valve assembly in the second operating mode.

[0015] In some embodiments, the drive device includes a hydraulic cylinder, the directional valve assembly includes a first working position and a second working position, the first working position has a first control end, the second working position has a second control end, the first automatic switching mechanism includes a first sequence valve and a second sequence valve, the inlet of the first sequence valve is connected to the connecting oil line between the first working port of the directional valve assembly and the rod chamber of the hydraulic cylinder, the outlet of the first sequence valve is connected to the first control end, and the pressure of the first control end is configured to switch the directional valve assembly to the first working position; the inlet of the second sequence valve is connected to the connecting oil line between the second working port of the directional valve assembly and the rodless chamber of the hydraulic cylinder, the outlet of the second sequence valve is connected to the second control end, and the pressure of the second control end is configured to switch the directional valve assembly to the second working position.

[0016] In some embodiments, the opening pressure of the first sequence valve is greater than the pressure on the connecting oil line between the first working port of the directional valve assembly and the rod chamber of the hydraulic cylinder in the first operating mode; and / or, the opening pressure of the second sequence valve is greater than the pressure on the connecting oil line between the second working port of the directional valve assembly and the rodless chamber of the hydraulic cylinder in the first operating mode.

[0017] In some embodiments, the control system further includes a first damping valve and a second damping valve, wherein the first damping valve is connected between the return port of the directional valve assembly and the first control terminal, and the second damping valve is connected between the return port of the directional valve assembly and the second control terminal.

[0018] In some embodiments, the first working position has a third control terminal, the second working position has a fourth control terminal, the first working port of the directional valve assembly is connected to the fourth control terminal, and the pressure of the fourth control terminal is configured to keep the directional valve assembly in the second working position; the second working port of the directional valve assembly is connected to the third control terminal, and the pressure of the third control terminal is configured to keep the directional valve assembly in the first working position.

[0019] In some embodiments, the area of ​​the first control terminal acting on the first working position is greater than the area of ​​the fourth control terminal acting on the second working position; and / or, the area of ​​the second control terminal acting on the second working position is greater than the area of ​​the third control terminal acting on the first working position.

[0020] In some embodiments, the control system includes a second automatic switching mechanism configured to automatically switch the reversing valve assembly in a first operating mode.

[0021] In some embodiments, the second automatic switching mechanism includes a movable frame and a first contact and a second contact respectively disposed at both ends of the movable frame. The movable frame is connected to the drive unit of the drive device. The reversing valve group includes a first contact and a second contact, and includes a first working position and a second working position. When the drive unit drives the movable frame to a position where the first contact contacts the first contact, the reversing valve group switches to the first working position to operate, so that the drive unit extends relative to the fixed part of the drive device. When the drive unit drives the movable frame to a position where the second contact contacts the second contact, the reversing valve group switches to the second working position to operate, so that the drive unit retracts relative to the fixed part of the drive device.

[0022] In some embodiments, the drive device includes a hydraulic cylinder, and the control system includes a hydraulic pump and a flow valve connected between the outlet of the hydraulic pump and a directional valve assembly. The flow valve is configured to regulate the flow rate of hydraulic oil entering the directional valve assembly.

[0023] In some embodiments, the control system further includes a relief valve connected in parallel with a flow valve, the relief valve being configured to limit the maximum pressure of the control system.

[0024] In some embodiments, the control system includes a check valve connected between the inlet and outlet of the directional valve assembly.

[0025] According to another aspect of this disclosure, a shearing method based on the above-described shearing device is provided, comprising:

[0026] When the shearing force required to cut the object is less than the maximum shearing force that the shearing equipment can provide, the second blade operates in the first working mode; and

[0027] When the shearing force required to cut the object being sheared is greater than or equal to the maximum shearing force that the shearing equipment can provide, the second blade operates in the second working mode.

[0028] Based on the above technical solution, the embodiments of this application have two working modes, and the corresponding working mode can be selected according to the actual situation, effectively expanding the application range of the shearing equipment; at the same time, when faced with different shearing needs, shearing can continue by switching working modes without replacing the shearing equipment, thus saving the time of replacing the shearing equipment and effectively improving the shearing efficiency. Attached Figure Description

[0029] The accompanying drawings, which are included to provide a further understanding of this disclosure and form part of this application, illustrate exemplary embodiments of this disclosure and are used to explain this disclosure, but do not constitute an undue limitation of this disclosure. In the drawings:

[0030] Figure 1 These are schematic diagrams illustrating the structure of some embodiments of the shearing device provided in this disclosure.

[0031] Figure 2 Hydraulic schematic diagrams for some embodiments of the shearing device provided in this disclosure.

[0032] Figure 3 The hydraulic schematic diagram of the hydraulic cylinder rod retracting during the first working mode of some embodiments of the shearing device provided in this disclosure.

[0033] Figure 4 The hydraulic schematic diagram of some embodiments of the shearing device provided in this disclosure when the cylinder rod of the hydraulic cylinder is extended in the first working mode.

[0034] Figure 5 The hydraulic schematic diagram of the hydraulic cylinder rod retraction during the second working mode of some embodiments of the shearing device provided in this disclosure.

[0035] Figure 6 The hydraulic schematic diagram of the hydraulic cylinder rod extension in the second working mode of some embodiments of the shearing device provided in this disclosure.

[0036] In the picture:

[0037] 1. Support; 2. First blade; 3. Second blade; 4. Drive unit; 5. Reversing valve assembly; 6. Control system; 7. Moving frame; 81. First contact element; 82. Second contact element;

[0038] 51. First control terminal; 52. Second control terminal; 53. Third control terminal; 54. Fourth control terminal; 55. First contact; 56. Second contact;

[0039] 611. First sequence valve; 612. Second sequence valve; 621. First damping valve; 622. Second damping valve; 63. Hydraulic pump; 64. Flow valve; 65. Relief valve; 66. Check valve. Detailed Implementation

[0040] The technical solutions in the embodiments of this disclosure will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are merely some embodiments of this disclosure, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this disclosure without creative effort are within the scope of protection of this disclosure.

[0041] In the description of this disclosure, it should be understood that the terms "center," "lateral," "longitudinal," "front," "rear," "left," "right," "upper," "lower," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this disclosure and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the scope of protection of this disclosure.

[0042] like Figure 1 As shown, in some embodiments of the shearing device provided in this application, the shearing device includes a support 1, a first blade 2, a second blade 3, a drive device 4, a reversing valve group 5, and a control system 6. The first blade 2 is disposed on the support 1, and the second blade 3 is movably disposed on the support 1. The drive device 4 is drivenly connected to the second blade 3 and is configured to drive the second blade 3 to move relative to the first blade 2 to complete the shearing action. The reversing valve group 5 is configured to change the driving direction of the drive device 4 so that the second blade 3 reciprocates. The control system 6 is configured to control the reversing valve group 5 to reverse, and the control system 6 is configured to enable the second blade 3 to have a first working mode and a second working mode. In the first working mode, the movement stroke of the second blade 3 relative to the first blade 2 is fixed; in the second working mode, the movement stroke of the second blade 3 relative to the first blade 2 is variable, and the maximum movement stroke of the second blade 3 in the second working mode is less than or equal to the movement stroke of the second blade 3 in the first working mode.

[0043] In this embodiment, the second blade 3 has two working modes. In the first working mode, the stroke of the second blade 3 relative to the first blade 2 is fixed, that is, the distance moved by the second blade 3 in each movement is constant. This mode is suitable for situations where the maximum shearing force provided by the shearing device is greater than or equal to the shearing force required to cut the object to be sheared, and can achieve the effect of cutting in one cut. Moreover, multiple cuts can be achieved by switching the reversing valve group 5.

[0044] In the second operating mode, the stroke of the second blade 3 relative to the first blade 2 is variable, meaning the distance the second blade 3 moves in one operation is not fixed. It should be understood that the distances traveled by the second blade 3 in two consecutive operations can be the same or different. This mode is suitable when the maximum shearing force provided by the shearing equipment is less than the shearing force required to cut the object. Combined with the reversing valve assembly 5, it facilitates multiple, repeated shearing operations with a short stroke. Furthermore, by reducing the stroke of the second blade 3, the stroke can be ended promptly by reversing when the maximum shearing force provided by the shearing equipment is less than the shearing force required to cut the object, preventing the second blade 3 from getting stuck by the object and affecting the normal operation of the shearing equipment.

[0045] In this embodiment, by setting two working modes, the appropriate working mode can be selected according to the actual situation, effectively expanding the applicability of the shearing equipment; at the same time, when faced with different shearing needs, shearing can continue by switching working modes without changing the shearing equipment, thus saving the time of changing the shearing equipment and effectively improving shearing efficiency.

[0046] In some embodiments, the control system 6 includes a first automatic switching mechanism configured to enable automatic switching of the second blade 3 between a first operating mode and a second operating mode, and to enable automatic reversing of the reversing valve assembly 5 in the second operating mode.

[0047] By setting up a first automatic switching mechanism, the second blade 3 can be automatically switched between the first working mode and the second working mode, reducing manual intervention, improving cutting efficiency, and saving labor costs.

[0048] Moreover, by enabling the second blade 3 to automatically switch working modes, in conjunction with the automatic reversing of the reversing valve group 5, it can automatically switch to the second working mode of small stroke and repeated cutting when the shearing force required for the object to be sheared is large, effectively avoiding jamming of the second blade 3 and improving shearing efficiency.

[0049] like Figure 2As shown, in some embodiments, the drive device 4 includes a hydraulic cylinder, the directional valve assembly 5 includes a first working position and a second working position, the first working position has a first control terminal 51, the second working position has a second control terminal 52, the first automatic switching mechanism includes a first sequence valve 611 and a second sequence valve 612, the inlet of the first sequence valve 611 is connected to the connecting oil line between the first working port of the directional valve assembly 5 and the rod chamber of the hydraulic cylinder, the outlet of the first sequence valve 611 is connected to the first control terminal 51, and the pressure of the first control terminal 51 is configured to switch the directional valve assembly 5 to the first working position; the inlet of the second sequence valve 612 is connected to the connecting oil line between the second working port of the directional valve assembly 5 and the rodless chamber of the hydraulic cylinder, the outlet of the second sequence valve 612 is connected to the second control terminal 52, and the pressure of the second control terminal 52 is configured to switch the directional valve assembly 5 to the second working position.

[0050] By setting a first sequence valve 611, when the pressure in the connecting oil line between the first working port of the reversing valve group 5 and the rod chamber of the hydraulic cylinder is greater than the opening pressure of the first sequence valve 611, the first sequence valve 611 is opened, thereby allowing the hydraulic oil in the first working port of the reversing valve group 5 to flow into the first control end 51 of the reversing valve group 5. Under the action of oil pressure, the first control end 51 can drive the reversing valve group 5 to switch to the first working position, causing the cylinder rod of the hydraulic cylinder to extend, so as to realize the shearing action of the second blade 3 and the first blade 2 on the object to be sheared.

[0051] By setting a second sequence valve 612, when the pressure in the connecting oil line between the second working port of the reversing valve group 5 and the rodless chamber of the hydraulic cylinder is greater than the opening pressure of the second sequence valve 612, the second sequence valve 612 is opened, allowing the hydraulic oil in the second working port of the reversing valve group 5 to flow into the second control end 52 of the reversing valve group 5. Under the action of oil pressure, the second control end 52 can drive the reversing valve group 5 to switch to the second working position, causing the cylinder rod of the hydraulic cylinder to retract, thereby releasing the second blade 3 from the object to be sheared.

[0052] By setting a first sequence valve 611 and a second sequence valve 612, when the shearing force required for the object to be sheared is large, the first sequence valve 611 or the second sequence valve 612 can be automatically opened by the continuous increase of oil pressure, switching to the second working mode, so as to achieve the effect of repeated shearing with a small stroke.

[0053] In some embodiments, the opening pressure of the first sequence valve 611 is greater than the pressure on the connecting oil line between the first working port of the directional valve group 5 and the rod chamber of the hydraulic cylinder in the first operating mode; and / or, the opening pressure of the second sequence valve 612 is greater than the pressure on the connecting oil line between the second working port of the directional valve group 5 and the rodless chamber of the hydraulic cylinder in the first operating mode.

[0054] By setting the opening pressure of the first sequence valve 611 to be greater than the pressure on the connecting oil line between the first working port of the directional valve group 5 and the rod chamber of the hydraulic cylinder in the first working mode, and setting the opening pressure of the second sequence valve 612 to be greater than the pressure on the connecting oil line between the second working port of the directional valve group 5 and the rodless chamber of the hydraulic cylinder in the first working mode, it is possible to prevent the first sequence valve 611 or the second sequence valve 612 from opening in the first working mode and affecting the normal operation of the first working mode.

[0055] In some embodiments, the control system 6 further includes a first damping valve 621 and a second damping valve 622. The first damping valve 621 is connected between the return port of the directional valve group 5 and the first control terminal 51, and the second damping valve 622 is connected between the return port of the directional valve group 5 and the second control terminal 52.

[0056] By setting the first damping valve 621 and the second damping valve 622, oil can be replenished to the first control terminal 51 and the second control terminal 52 of the directional valve assembly 5 in a timely manner during the first operating mode, thus preventing cavitation. The first damping valve 621 and the second damping valve 622 can also divert the control oil flow of the first sequence valve 611 and the second sequence valve 612 to reduce the switching speed of the directional valve assembly 5 and reduce impact.

[0057] In some embodiments, the first working position has a third control terminal 53, the second working position has a fourth control terminal 54, the first working port of the directional valve assembly 5 is connected to the fourth control terminal 54, and the pressure of the fourth control terminal 54 is configured to keep the directional valve assembly 5 in the second working position; the second working port of the directional valve assembly 5 is connected to the third control terminal 53, and the pressure of the third control terminal 53 is configured to keep the directional valve assembly 5 in the first working position.

[0058] By setting the third control terminal 53 and the fourth control terminal 54, it is beneficial to maintain the working stability of the reversing valve group 5.

[0059] In some embodiments, the area of ​​the first control terminal 51 acting on the first working position is greater than the area of ​​the fourth control terminal 54 acting on the second working position; and / or, the area of ​​the second control terminal 52 acting on the second working position is greater than the area of ​​the third control terminal 53 acting on the first working position.

[0060] By setting the area of ​​the first control terminal 51 acting on the first working position to be greater than the area of ​​the fourth control terminal 54 acting on the second working position, it can be ensured that after the hydraulic oil flows to the first control terminal 51 in the second working mode, the force of the hydraulic oil in the first control terminal 51 on the reversing valve group 5 is greater than the force of the hydraulic oil in the fourth control terminal 54 on the reversing valve group 5, so as to ensure that the first sequence valve 611 can push the reversing valve group 5 to switch direction after it is opened.

[0061] By setting the area of ​​the second control terminal 52 acting on the second working position to be greater than the area of ​​the third control terminal 53 acting on the first working position, it can be ensured that after the hydraulic oil flows to the second control terminal 52 in the second working mode, the force of the hydraulic oil in the second control terminal 52 on the reversing valve group 5 is greater than the force of the hydraulic oil in the third control terminal 53 on the reversing valve group 5, so as to ensure that the second sequence valve 612 can push the reversing valve group 5 to switch after it is opened.

[0062] In some embodiments, the control system 6 includes a second automatic switching mechanism configured to automatically switch the reversing valve assembly 5 in a first operating mode.

[0063] By setting a second automatic switching mechanism, the reversing valve group 5 can be automatically reversed in the first working mode, and the second blade 3 can be automatically reciprocated, reducing manual intervention and improving shearing efficiency.

[0064] In some embodiments, the second automatic switching mechanism includes a movable frame 7 and a first contact 81 and a second contact 82 respectively disposed at both ends of the movable frame 7. The movable frame 7 is connected to the drive unit of the drive device 4. The reversing valve group 5 includes a first contact 55 and a second contact 56. The reversing valve group 5 includes a first working position and a second working position. When the drive unit drives the movable frame 7 to a position where the first contact 81 contacts the first contact 55, the reversing valve group 5 switches to the first working position to operate, so that the drive unit extends relative to the fixed part of the drive device 4. When the drive unit drives the movable frame 7 to a position where the second contact 82 contacts the second contact 56, the reversing valve group 5 switches to the second working position to operate, so that the drive unit retracts relative to the fixed part of the drive device 4.

[0065] When the first contact 81 contacts the first contact 55, the momentum of the moving frame 7 is transferred to the reversing valve group 5, causing the reversing valve group 5 to switch to the first working position, so that the driving part extends relative to the fixed part of the driving device 4, and drives the first contact 81 on the moving frame 7 away from the first contact 55.

[0066] When the second contact 82 contacts the second contact 56, the momentum of the moving frame 7 is transferred to the reversing valve group 5, causing the reversing valve group 5 to switch to the second working position, so that the driving part retracts relative to the fixed part of the driving device 4, and drives the second contact 82 on the moving frame 7 away from the second contact 56.

[0067] In some embodiments, the drive device 4 includes a hydraulic cylinder, and the control system 6 includes a hydraulic pump 63 and a flow valve 64. The flow valve 64 is connected between the outlet of the hydraulic pump 63 and the directional valve assembly 5, and the flow valve 64 is configured to regulate the flow rate of hydraulic oil entering the directional valve assembly 5.

[0068] By setting the flow valve 64, the flow rate of hydraulic oil entering the directional valve group 5 can be adjusted, thereby adjusting the movement speed and directional frequency of the hydraulic cylinder.

[0069] In some embodiments, the control system 6 further includes a relief valve 65 connected in parallel with the flow valve 64, the relief valve 65 being configured to limit the maximum pressure of the control system 6.

[0070] By setting the relief valve 65, it can be used in conjunction with the flow valve 64. When the outflow of the hydraulic pump 63 is large, the excess oil can flow back to the oil tank through the relief valve 65.

[0071] The relief valve 65 is connected in parallel with the flow valve 64, which can limit the maximum working pressure of the control system 6, prevent overload, and protect the working parts.

[0072] In some embodiments, the control system 6 includes a check valve 66 connected between the oil inlet and the oil return port of the directional valve assembly 5.

[0073] By using a check valve 66 connected in parallel with the reversing valve group 5, oil can be replenished to the hydraulic cylinder when the control system is working, preventing cavitation caused by excessive reversing frequency of the hydraulic cylinder.

[0074] Based on the shearing devices in the above embodiments, this application also provides a shearing method, including:

[0075] When the shearing force required to cut the object is less than the maximum shearing force that the shearing equipment can provide, the second blade 3 operates in the first working mode; and

[0076] When the shearing force required to cut the object being sheared is greater than or equal to the maximum shearing force that the shearing equipment can provide, the second blade 3 operates in the second working mode.

[0077] The positive technical effects of the shearing device in the above embodiments also apply to the shearing method, and will not be repeated here.

[0078] The following is in conjunction with the appendix Figures 1 to 6 The structure and operation of one embodiment of the shearing device provided in this application will be described as follows:

[0079] like Figure 1As shown, the shearing device includes a support 1, a blade assembly, a drive unit 4, a reversing valve group 5, a control system 6, a moving frame 7, and a contact assembly. The blade assembly includes a first blade 2 and a second blade 3. The first blade 2 is fixedly mounted on the support 1, and the second blade 3 is movably mounted on the support 1. The second blade 3 is connected to the moving frame 7. The fixed part of the drive unit 4 is mounted on the support 1, and the drive part of the drive unit 4 is drivenly connected to the moving frame 7 to drive the moving frame 7 to move the second blade 3 relative to the first blade 2. The reversing valve group 5 is used to reverse the driving direction of the drive unit 4, causing the second blade 3 to reciprocate. The control system 6 is used to control the reversing of the reversing valve group 5. The moving frame 7 is L-shaped. The contact assembly includes a first contact element 81 and a second contact element 82. The first contact 81 and the second contact 82 are respectively disposed at both ends of the movable frame 7. When the driving part of the driving device 4 extends relative to the fixed part, the second contact 82 contacts the second contact 56 on the reversing valve group 5 to reverse the reversing valve group 5 and retract the driving part of the driving device 4 relative to the fixed part. When the driving part of the driving device 4 retracts relative to the fixed part, the first contact 81 contacts the first contact 55 on the reversing valve group 5 to reverse the reversing valve group 5 and extend the driving part of the driving device 4 relative to the fixed part.

[0080] When the shearing equipment is working, the support 1 remains fixed, and the driving part of the drive device 4 pushes the second blade 3 to reciprocate. The second blade 3 and the first blade 2 generate relative motion to achieve the shearing effect.

[0081] like Figure 2 As shown, the reversing valve assembly 5 includes a two-position four-way reversing valve, which includes a first working position and a second working position. The side of the first working position away from the second working position is provided with a first control terminal 51, a third control terminal 53 and a first contact 55. The side of the second working position away from the first working position is provided with a second control terminal 52, a fourth control terminal 54 and a second contact 56.

[0082] The effective area of ​​the first control terminal 51 is greater than that of the fourth control terminal 54. When the first control terminal 51 and the fourth control terminal 54 are simultaneously acted upon by hydraulic oil, the driving force on the first control terminal 51 is greater than the force on the fourth control terminal 54. Therefore, after the first sequence valve 611 is opened, it can push the reversing valve group 5 to reverse.

[0083] The working area of ​​the second control terminal 52 is greater than that of the third control terminal 53. When the second control terminal 52 and the third control terminal 53 are simultaneously acted upon by hydraulic oil, the driving force on the second control terminal 52 is greater than the force on the third control terminal 53. Therefore, after the second sequence valve 612 is opened, it can push the reversing valve group 5 to reverse.

[0084] The working area of ​​the hydraulic cylinder is much larger than that of the first control end 51, the second control end 52, the third control end 53 and the fourth control end 54. When the contact component contacts the contact point on the reversing valve group, there is sufficient driving force to make the valve core of the reversing valve group 5 move.

[0085] The first contact 55 is spring-loaded onto the directional valve assembly 5 to reduce the impact force of the first contact 81 on the first contact 55 when the first contact 81 contacts the first contact 55, thus protecting the directional valve assembly 5. The first contact 55 protrudes from the first control terminal 51 and the third control terminal 53 to ensure that the first contact 81 contacts the first contact 55 first without impacting the first control terminal 51 and the third control terminal 53.

[0086] The second contact 56 is spring-loaded onto the directional valve assembly 5 to reduce the impact force of the second contact 82 on the second contact 56 when the second contact 82 contacts it, thus protecting the directional valve assembly 5. The second contact 56 protrudes from the second control terminal 52 and the fourth control terminal 54 to ensure that the second contact 82 contacts the second contact 56 first, without impacting the second control terminal 52 and the fourth control terminal 54.

[0087] When the first contact 81 contacts the first contact 55 or the second contact 82 contacts the second contact 56, the valve core of the two-position four-way directional valve can be driven to change direction.

[0088] The control system 6 includes a first sequence valve 611, a second sequence valve 612, a first damping valve 621, a second damping valve 622, a hydraulic pump 63, a flow valve 64, a relief valve 65, and a check valve 66. The drive unit 4 includes a hydraulic cylinder.

[0089] The A and B ports of the two-position four-way directional valve respectively lead out control oil to the third control terminal 53 and the fourth control terminal 54, which are used to keep the valve core in place after the valve core moves. The hydraulic oil output from the A and B ports of the two-position four-way directional valve drives the hydraulic cylinder to reciprocate.

[0090] The first sequence valve 611 is connected to the rod chamber of the hydraulic cylinder in parallel, and the second sequence valve 612 is connected to the rodless chamber of the hydraulic cylinder in parallel. When the working pressure increases, the first sequence valve 611 or the second sequence valve 612 opens and outputs control oil to act on the first control end 51 or the second control end 52 of the two-position four-way directional valve, overcoming the hydraulic pressure at the third control end 53 or the fourth control end 54, and driving the valve core to switch.

[0091] The first damping valve 621 and the second damping valve 622 can replenish the oil in the first control end 51 or the second control end 52 during the mechanical switching of the two-position four-way directional valve, thus preventing cavitation. The first damping valve 621 and the second damping valve 622 can also divert the control oil flow output from the first sequence valve 611 and the second sequence valve 612 to reduce the switching speed of the two-position four-way directional valve and minimize impact.

[0092] The hydraulic oil output from the hydraulic pump 63 passes through the three-way flow valve 64. The three-way flow valve 64 regulates the flow rate, allowing excess flow from the hydraulic pump 63 to be discharged back to the oil tank via the relief valve 65. This, in turn, regulates the flow rate of the hydraulic oil entering the two-position four-way directional valve, ultimately adjusting the movement speed and reversing frequency of the hydraulic cylinder. The relief valve 65 is connected in parallel with the outlet of the three-way flow valve 64. The relief valve 65 limits the maximum system pressure, preventing overload and protecting the working components.

[0093] The one-way valve 66 connects the inlet and outlet of the two-position four-way directional valve. After the system is working, it can replenish oil to the hydraulic cylinder to prevent cavitation caused by high switching frequency of the hydraulic cylinder.

[0094] Work process:

[0095] The second blade 3 has a first working mode and a second working mode.

[0096] In the first working mode, such as Figure 3 As shown, the hydraulic oil output by the hydraulic pump 63 passes through the flow valve 64 and then enters the two-position four-way directional valve. The A port of the two-position four-way directional valve outputs two control oil circuits and one main oil circuit. One control oil circuit acts on the fourth control terminal 54 on the right side of the directional valve core, keeping the valve core in the right position. The other control oil circuit acts on the first sequence valve 611. At this time, it is a low-pressure condition, and the pressure does not reach the opening pressure set by the first sequence valve 611, so the first sequence valve 611 is closed. The main oil circuit acts on the rod chamber of the hydraulic cylinder, causing the cylinder rod to retract. The cylinder rod drives the moving frame 7 to move. When the hydraulic cylinder retracts to the end of its stroke, the first contact 81 on the moving frame 7 contacts the first contact 55 on the left side of the directional valve, driving the directional valve core to move to the right, and the directional valve operates in the left position. Figure 4 As shown, the B port of the two-position four-way directional valve outputs a control oil that acts on the third control end 53 on the left side of the valve core, keeping the valve core in the left position. The main oil circuit acts on the rodless chamber of the hydraulic cylinder, causing the hydraulic cylinder to reverse. The cylinder rod of the hydraulic cylinder extends, and this cycle repeats. The hydraulic cylinder automatically reverses, which can drive the second blade 3 to reciprocate and shear.

[0097] In the second working mode, such as Figure 5As shown, when the tree branch being cut is thick and difficult to cut, the hydraulic cylinder is jammed by the branch, its movement is obstructed, and it cannot move to the end of its stroke. At this time, the hydraulic cylinder does not retract to its position, and the first contact 81 on the moving frame 7 cannot touch the first contact 55 on the left side of the two-position four-way directional valve. However, the oil pressure in the rod chamber of the hydraulic cylinder will rise to the opening pressure set by the first sequence valve 611, opening the first sequence valve 611. The output control oil acts on the first control end 51 on the left side of the two-position four-way directional valve, causing the two-position four-way directional valve to work in the left position. At this time, the directional valve reverses, and the hydraulic system oil circuit is as follows: Figure 6 As shown, if the cutting teeth are still obstructed by the tree branch after the hydraulic cylinder reverses direction, the oil pressure in the rodless chamber of the hydraulic cylinder will increase and open the second sequence valve 612. The output control oil will act on the second control terminal 52 on the right side of the two-position four-way reversing valve, and hydraulic reversing will be performed again. At this time, the stroke of the hydraulic cylinder is short. Due to the action of the flow valve 64, the flow rate input to the hydraulic cylinder remains unchanged, and the reversing frequency of the hydraulic cylinder increases. The tree branch will be repeatedly sheared at a high frequency until it is cut off. At the same time, the cutting teeth can be prevented from getting stuck in the tree branch.

[0098] The shearing equipment provided in this application has two working modes. In the low-pressure mode, when shearing small-diameter branches with low required shearing force, the second blade can complete the pruning in a single stroke. The hydraulic cylinder automatically reciprocates during this mode, controlled by a mechanical reversing method using contact points. In the high-pressure mode, when the shearing conditions are complex and difficult, the system automatically switches to high-pressure mode, employing hydraulic control for reciprocating shearing. In this mode, the hydraulic cylinder has a short stroke and a high reversing frequency, allowing the branches to be repeatedly pruned until they are severed, thus preventing blade jamming. Furthermore, the control system includes a flow valve to adjust the flow rate into the hydraulic cylinder, maintaining a stable cylinder speed and allowing for adjustment of the pruning speed and frequency according to working conditions.

[0099] The shearing equipment provided in this application can be hedge trimmers for garden maintenance; it can also be hydraulic shears for use in engineering machinery and other fields.

[0100] The description of the various embodiments above tends to emphasize the differences between the various embodiments. The similarities or similarities between them can be referred to, and for the sake of brevity, they will not be repeated here.

[0101] Those skilled in the art will understand that, in the methods described in the specific embodiments, the order in which the steps are written does not imply a strict execution order and does not constitute any limitation on the implementation process. The specific execution order of each step should be determined by its function and possible internal logic.

[0102] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this disclosure and not to limit them; although this disclosure has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications can still be made to the specific implementation of this disclosure or equivalent substitutions can still be made to some technical features without departing from the principles of this disclosure, and such modifications and equivalent substitutions should all be covered within the scope of the technical solutions claimed in this disclosure.

Claims

1. A shearing device, comprising: Support (1); The first blade (2) is disposed on the bracket (1); The second blade (3) is movably mounted on the bracket (1); A drive device (4) is driven to the second blade (3), and the drive device (4) is configured to drive the second blade (3) to move relative to the first blade (2) to complete the shearing action; The reversing valve assembly (5) is configured to change the driving direction of the drive device (4) so ​​that the second blade (3) reciprocates. and The control system (6) is configured to control the reversing valve assembly (5) to reverse, and the control system (6) is configured to give the second blade (3) a first working mode and a second working mode. In the first working mode, the movement stroke of the second blade (3) relative to the first blade (2) is fixed; in the second working mode, the movement stroke of the second blade (3) relative to the first blade (2) is variable, and the maximum movement stroke of the second blade (3) in the second working mode is less than or equal to the movement stroke of the second blade (3) in the first working mode. The control system (6) includes a first automatic switching mechanism configured to enable the second blade (3) to automatically switch between the first working mode and the second working mode, and to enable the reversing valve group (5) to automatically switch in the second working mode. The drive device (4) includes a hydraulic cylinder, and the directional valve group (5) includes a first working position and a second working position. The first working position has a first control terminal (51), and the second working position has a second control terminal (52). The first automatic switching mechanism includes a first sequence valve (611) and a second sequence valve (612). The inlet of the first sequence valve (611) is connected to the connecting oil line between the first working port of the directional valve group (5) and the rod chamber of the hydraulic cylinder. The outlet of the first sequence valve (611) is connected to the first control terminal (51). The pressure of the first control terminal (51) is configured to switch the directional valve group (5) to the first working position. The inlet of the second sequence valve (612) is connected to the connecting oil line between the second working port of the directional valve group (5) and the rodless chamber of the hydraulic cylinder. The outlet of the second sequence valve (612) is connected to the second control terminal (52). The pressure of the second control terminal (52) is configured to switch the directional valve group (5) to the second working position.

2. The shearing device according to claim 1, characterized in that, The opening pressure of the first sequence valve (611) is greater than the pressure on the connecting oil line between the first working port of the directional valve group (5) and the rod chamber of the hydraulic cylinder in the first working mode; and / or, the opening pressure of the second sequence valve (612) is greater than the pressure on the connecting oil line between the second working port of the directional valve group (5) and the rodless chamber of the hydraulic cylinder in the first working mode.

3. The shearing device according to claim 1, characterized in that, The control system (6) further includes a first damping valve (621) and a second damping valve (622). The first damping valve (621) is connected between the oil return port of the reversing valve group (5) and the first control terminal (51), and the second damping valve (622) is connected between the oil return port of the reversing valve group (5) and the second control terminal (52).

4. The shearing device according to claim 1, characterized in that, The first working position has a third control terminal (53), the second working position has a fourth control terminal (54), the first working port of the reversing valve group (5) is connected to the fourth control terminal (54), and the pressure of the fourth control terminal (54) is configured to keep the reversing valve group (5) working in the second working position; the second working port of the reversing valve group (5) is connected to the third control terminal (53), and the pressure of the third control terminal (53) is configured to keep the reversing valve group (5) working in the first working position.

5. The shearing device according to claim 4, characterized in that, The area of ​​the first control terminal (51) acting on the first working position is greater than the area of ​​the fourth control terminal (54) acting on the second working position; and / or, the area of ​​the second control terminal (52) acting on the second working position is greater than the area of ​​the third control terminal (53) acting on the first working position.

6. The shearing device according to claim 1, characterized in that, The control system (6) includes a second automatic switching mechanism configured to automatically switch the reversing valve group (5) in the first operating mode.

7. The shearing device according to claim 6, characterized in that, The second automatic switching mechanism includes a movable frame (7) and a first contact (81) and a second contact (82) respectively disposed at both ends of the movable frame (7). The movable frame (7) is connected to the driving part of the driving device (4). The reversing valve group (5) includes a first contact (55) and a second contact (56). The reversing valve group (5) includes a first working position and a second working position. When the driving part drives the movable frame (7) to a position where the first contact (81) contacts the first contact (55), the reversing valve group (5) switches to the first working position to make the driving part extend relative to the fixed part of the driving device (4). When the driving part drives the movable frame (7) to a position where the second contact (82) contacts the second contact (56), the reversing valve group (5) switches to the second working position to make the driving part retract relative to the fixed part of the driving device (4).

8. The shearing device according to claim 1, characterized in that, The drive device (4) includes a hydraulic cylinder, and the control system (6) includes a hydraulic pump (63) and a flow valve (64). The flow valve (64) is connected between the outlet of the hydraulic pump (63) and the reversing valve assembly (5). The flow valve (64) is configured to regulate the flow rate of hydraulic oil entering the reversing valve assembly (5).

9. The shearing device according to claim 8, characterized in that, The control system (6) also includes an overflow valve (65) connected in parallel with the flow valve (64), and the overflow valve (65) is configured to limit the maximum pressure of the control system (6).

10. The shearing device according to claim 1, characterized in that, The control system (6) includes a check valve (66) connected between the oil inlet and the oil return port of the directional valve group (5).

11. A shearing method based on the shearing device according to any one of claims 1 to 10, comprising: When the shearing force required to cut the object to be sheared is less than the maximum shearing force that the shearing device can provide, the second blade (3) operates in the first working mode; and When the shearing force required to cut the object to be sheared is greater than or equal to the maximum shearing force that the shearing device can provide, the second blade (3) operates in the second working mode.

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