Ratchet power-saving mechanism and high-branch shears thereof

Abstract

The utility model discloses a kind of ratchet power-saving mechanism and its high branch shears, which belong to garden pruning machinery technical field.It mainly includes support seat, the support seat is equipped with ratchet power-saving mechanism, support arm is fixedly connected with support seat, support arm and force applying mechanism are equipped with force applying reset component, support seat and force applying mechanism are connected with pull rope through pulley, pruning knife is equipped with cutting edge at the end away from sector gear two, support arm is fixedly connected with the knife rest matched with cutting edge, pruning knife is equipped with blade reset component between the position away from rotation center and support arm.The utility model adds ratchet pawl mechanism one and ratchet pawl mechanism two, supports the segmented operation of multiple "force-reset-again force", does not need to exert large force singly, adapts different physical force user, especially convenient for high altitude branch ground shearing.

Description

Technical Field

[0001] This utility model belongs to the field of garden pruning machinery technology, and more specifically, it relates to a ratchet labor-saving mechanism and its high branch shears. Background Technology

[0002] High-branch shears are common gardening pruning tools, mainly used for shaping and pruning the high branches of ornamental trees, fruit trees, or flowers. They are generally used to remove excess and diseased branches. Currently, most commercially available high-branch shears have a pull-rope structure. For example, patent publication number "CN202262282U" discloses a type of high-branch shears for shaping and pruning tall trees, including a blade holder with a support rod connected to the lower part. The blade holder has a fixed blade edge, and a movable blade edge adapted to the fixed blade edge is hinged to one side of the blade holder. A connecting rod is hinged to the other side of the blade holder, and an elongated hole is provided on the connecting rod. The handle of the movable blade edge is movably connected to the elongated hole. A return spring is provided between the rear of the connecting rod and the blade holder, and a pulley is provided at the free end of the connecting rod. A pull rope is fixed to the blade holder, and the free end of the pull rope extends downwards after passing through the pulley. Shaping and pruning of tall trees is achieved by pulling the pull rope.

[0003] However, in actual use, the following problems still exist: During pruning, the pruning shears are engaged by the pulling force of the long rope to cut the branches. However, the pulling stroke of the rope is relatively long, and the rope must be pulled all the way to cut the branches in one go, which is very laborious and labor-intensive for workers. When facing thicker branches, the shearing force is insufficient, and the rope may not be able to be pulled or the cutting may not be complete, which cannot meet the needs of efficient pruning. Utility Model Content

[0004] The technical problem to be solved by this utility model is to overcome the shortcomings of the prior art and provide a ratchet force-saving mechanism and its high branch shears. It adds a ratchet pawl mechanism one and a ratchet pawl mechanism two to support multiple segmented operations of "applying force-resetting-applying force" without having to apply a large force at once. It is suitable for users with different physical strength and is especially convenient for cutting branches on the ground at height.

[0005] The ratchet-based force-saving mechanism includes a pawl mechanism and a ratchet component. The pawl mechanism includes a first pawl, and a pawl limiting block is provided on the side of the first pawl away from the engaging portion. The ratchet component is provided with a ratchet tooth that can engage with the first pawl, and a sector gear is provided on the side of the ratchet component away from the ratchet tooth.

[0006] Preferably, the end of the first ratchet is provided with a ratchet limiting block for engaging and limiting the first pawl.

[0007] Preferably, it further includes a force-applying mechanism and a support arm. A pawl mechanism is rotatably mounted on the force-applying mechanism, and the force-applying mechanism is located away from the mounting fulcrum of the pawl mechanism. A pawl elastic component is provided between the pawl mechanism and the pawl mechanism. A ratchet component is rotatably connected to the force-applying mechanism and the support arm respectively. A pawl reset baffle that cooperates with the pawl limit block is fixedly connected to the support arm.

[0008] Preferably, the support arm is rotatably connected to a trimmer and a central gear. The trimmer is provided with a second ratchet and a second sector gear at one end near the ratchet. The second sector gear is connected to the first sector gear through the central gear. The support arm is provided with a second ratchet mechanism that engages with the second ratchet.

[0009] Preferably, the second pawl mechanism includes a pawl and a second pawl. One end of the pawl is rotatably connected to the support arm, and a rotational elastic component is provided between the pawl and the support arm. The other end of the pawl is provided with a slot. A limiting shaft for rotating and limiting the pawl is fixedly connected to the support arm. The second pawl is rotatably connected to the support arm near the middle, and a rotational elastic component is provided between the second pawl and the support arm. One end of the second pawl can be engaged and fixed with the second ratchet tooth, and the other end of the second pawl can be engaged and cooperated with the slot.

[0010] Preferably, both the first and second rotating elastic components are torsion springs, and the trimmer is fixedly connected to a top plate that can drive the second pawl into the slot and an unlocking plate that can drive the second pawl out of the slot.

[0011] Preferably, the second ratchet mechanism includes a fixed plate, which is fixedly connected to the support arm. The fixed plate has a long ratchet that can slide back and forth to the second ratchet. A spring plate is provided at the end of the long ratchet away from the second ratchet. The spring plate is fixedly connected to the support arm and abuts against the long ratchet. A sliding groove is provided on the fixed plate. A locking slider and an unlocking slider are slidably connected in the sliding groove. The locking slider and the unlocking slider are fixedly connected. A compression spring is provided between the end of the locking slider away from the long ratchet and the inner end face of the sliding groove. A locking platform that cooperates with the locking slider is fixedly connected to the long ratchet.

[0012] Preferably, when the compression spring is in its normal state, the unlocking slider extends out of the groove, and the locking slider can extend and engage with the locking platform. The trimmer is fixedly connected to an unlocking plate that can drive the unlocking slider to retract into the groove.

[0013] Preferably, the locking platform and the locking slider are respectively provided with matching inclined surfaces, and the fixing plate is provided with a limiting platform for abutting against the locking platform.

[0014] The aforementioned high-branch shears include a support base, on which a ratchet-type force-saving mechanism is provided. A support arm is fixedly connected to the support base, and a force-applying mechanism is provided between the support arm and the force-applying mechanism. A pull rope is connected between the support base and the force-applying mechanism via a pulley. A blade is provided at the end of the shears away from the second sector gear. A blade holder that cooperates with the blade is fixedly connected to the support arm. A blade reset assembly is provided between the shears and the support arm at a position away from the rotation center.

[0015] Compared with the prior art, the beneficial effects of this utility model are: 1. This utility model uses a ratchet mechanism to work with a ratchet wheel, taking advantage of the unidirectional transmission characteristics of the ratchet wheel and the optimized transmission ratio of sector gear one, central gear, and sector gear two to convert the pulling force of the rope into the cutting force of the trimmer. It supports multiple segmented operations of "applying force-resetting and reapplying force", eliminating the need to apply a large force at once, making it suitable for users with different physical strengths, and especially convenient for cutting branches from the ground at height.

[0016] 2. Add a pawl limit block to prevent the pawl from rotating excessively; add a pawl elastic component to keep the pawl and ratchet teeth in contact and ensure that the power is transmitted in one direction without disengaging; at the same time, add a second pawl mechanism that cooperates with the second ratchet teeth to lock the pruning shears to prevent reverse retraction and avoid loss of cutting stroke due to the reaction force of the branches.

[0017] 3. The force application and reset component drives the force application mechanism to automatically return to its original position, and the blade reset component drives the trimmer to return to its initial position after completing the cutting. The unlocking structure (such as the unlocking plate pushing the unlocking slider and the top plate lifting the second pawl) realizes automatic unlocking of the pawl, eliminating the need for manual adjustment, shortening the single cutting cycle time, and making it more convenient to use. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the ratchet force-saving mechanism disclosed in Embodiment 1; Figure 2 This is a schematic diagram of the ratchet force-saving mechanism disclosed in Embodiment 2; Figure 3 This is a schematic diagram showing the engagement of the chuck and the second pawl; Figure 4 This is a front structural diagram of the high-branch shears disclosed in Embodiment 4; Figure 5 This is a schematic diagram of the back structure of the high-branch shears disclosed in Embodiment 4; Figure 6 This is a schematic diagram of the structure in the trimming state of Example 4; Figure 7 This is a front structural schematic diagram of the pawl mechanism 2 disclosed in Embodiment 3; Figure 8 This is a schematic diagram of the back structure of the pawl mechanism 2 disclosed in Embodiment 3; Figure 9This is a front structural diagram of the high-branch shears disclosed in Example 5; Figure 10 for Figure 9 A magnified view of part A in the middle; Figure 11 This is a schematic diagram of the back structure of the high-branch shears disclosed in Example 5.

[0019] In the diagram, 1. Force application mechanism; 101. Force application and reset assembly; 2. Ratchet; 201. Ratchet tooth one; 202. Sector gear one; 203. Ratchet tooth limiting block; 3. Pawl mechanism one; 301. First pawl; 302. Pawl elastic assembly; 303. Pawl limiting block; 4. Central gear; 5. Support arm; 501. Pawl reset baffle; 6. Trimming shears; 601. Blade reset assembly; 602. Rotating baffle; 603. Sector gear two; 604. Ratchet two; 605. Unlocking plate; 606. Top plate; 7. Pawl Mechanism II; 701. Pawl; 7011. Rotation Support I; 7012. Rotation Elastic Component I; 7013. Limiting Shaft; 702. Second Pawl; 7021. Rotation Support II; 7022. Rotation Elastic Component II; 7023. Fixed Shaft; 703. Fixed Plate; 7031. Limiting Stage; 704. Unlocking Slider; 705. Long Pawl; 7051. Locking Stage; 706. Spring Plate; 707. Locking Slider; 708. Compression Spring; 8. Knife holder; 9. Pull rope; 10. Support base. Detailed Implementation

[0020] The present invention will be further described below with reference to the accompanying drawings: The directional terms used in the detailed description paragraphs are only for the convenience of those skilled in the art to understand the technical solutions described in this application based on the visual orientation shown in the accompanying drawings. Unless otherwise expressly specified and limited, the terms "setting," "installation," "connection," etc., should be interpreted broadly, and those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0021] Example 1: like Figure 1As shown, a ratchet-based force-saving mechanism includes a pawl mechanism 3 and a ratchet component 2. In use, the first pawl 301 is rotatably connected to the force-applying mechanism 1. The pawl mechanism 3 receives power and engages with the ratchet component 2. During power transmission, it drives the ratchet component 2 to rotate unidirectionally, facilitating subsequent cooperation between the ratchet component 2 and the force-applying mechanism 1 to achieve force-saving operation. Specifically, the pawl mechanism 3 includes a first pawl 301. A pawl limiting block 303 is provided on the side of the first pawl 301 away from the engaging portion. The pawl limiting block 303 limits the maximum rotation angle of the first pawl 301, preventing it from rotating excessively due to excessive force or vibration, thus avoiding it from disengaging from the engagement range with the ratchet tooth 201 and ensuring the stability of the engaging transmission. The ratchet 2 is equipped with a ratchet tooth 201 that engages with the first pawl 301. Through this unidirectional engagement, the ratchet tooth 201 converts the oscillation of the first pawl 301 into a unidirectional rotational motion of the ratchet 2, thus achieving unidirectional power transmission during branch pruning. A sector gear 202 is located on the side of the ratchet 2 away from the ratchet tooth 201. This sector gear 202 converts the rotational motion of the ratchet 2 into gear meshing transmission, facilitating the subsequent opening of the pruning shears 6.

[0022] In this embodiment, the end of the ratchet 201 is provided with a ratchet limiting block 203 for engaging and limiting the first pawl 301. When the ratchet 201 rotates to the point where the ratchet limiting block 203 contacts the first pawl 301, the ratchet limiting block 203 can restrict the radial displacement of the first pawl 301 within the ratchet 201, preventing the first pawl 301 from dislodging from the ratchet 201, thus enhancing the engagement reliability and ensuring that power is effectively transmitted to the ratchet component 2.

[0023] Example 2: like Figure 2 and Figure 3 As shown, a ratchet force-saving mechanism, based on Embodiment 1, further includes a force-applying mechanism 1 and a support arm 5. The force-applying mechanism 1 is an operating component for the user to apply external force, used to convert the tension of the pull rope into the driving force of the mechanism. The support arm 5 is a fixed support frame for the mechanism, providing an installation reference and motion support for components such as the ratchet 2 and the trimmer 6. The pawl mechanism 3 is rotatably mounted on the force-applying mechanism 1, and the force-applying mechanism 1 is located away from the mounting fulcrum of the pawl mechanism 3. A pawl elastic component 302 is provided between the force-applying mechanism 1 and the pawl limiting block 303 of the pawl mechanism 3. In this embodiment, the pawl elastic component 302 is a tension spring, which can provide a continuous preload to the first pawl 301, so that the first pawl 301 always tends to engage with the ratchet 201, ensuring that the first pawl 301 and the ratchet 201 always remain in a locked state during transmission.

[0024] The ratchet component 2 is rotatably connected to the force-applying mechanism 1 and the support arm 5 near their ends via bolts, ensuring that the force-applying mechanism 1 and the ratchet component 2 rotate stably around the same fixed axis. This prevents deviation during rotation from causing the sector gear 202 to fail to mesh with the central gear 4, thus ensuring the installation stability of the ratchet component 2 and limiting the rotation center of the force-applying mechanism 1. A pawl reset baffle 501 that cooperates with the pawl limit block 303 is fixedly connected to the support arm 5. It should be noted that under normal conditions, the pawl reset baffle 501 abuts against the pawl limit block 303, the pawl elastic component 302 is in a stretched state, and the first pawl 301 is disengaged from the ratchet tooth 201. When shearing force is applied, the force-applying mechanism 1 drives the first pawl 301 to rotate downward. At this time, the pawl limiting block 303 disengages from the pawl reset baffle 501. Under the elastic reset action of the pawl elastic component 302, the first pawl 301 engages with the ratchet tooth 201. When the force-applying mechanism 1 drives the first pawl 301 to reset in the opposite direction, the pawl reset baffle 501 contacts the pawl limiting block 303, which can limit the reset position of the first pawl 301, so that the first pawl 301 stops at the initial position, and the first pawl 301 disengages from the ratchet tooth 201 and no longer engages or limits the ratchet tooth 201. For ease of use, the trimmer 6 resets after trimming.

[0025] The arm 5 is rotatably connected to the trimmer 6 and the central gear 4. The trimmer 6 and the central gear 4 are connected to a rotating baffle 602 on their respective rotating shafts. The rotating baffle 602 has a limiting function, which can ensure the transmission effect between the central gear 4 and the trimmer 6 and prevent them from rotating out of position. The trimmer 6 rotates around the arm 5 through the rotatable connection. Its rotation action directly corresponds to the opening and closing of the blade, thereby completing the trimming operation. The trimmer scissors 6 has a second ratchet 604 and a second sector gear 603 at one end near the ratchet 2. The second sector gear 603 is connected to the first sector gear 202 via a central gear 4. The central gear 4 acts as a transmission medium, connecting the first sector gear 202 and the second sector gear 603, and meshing with both the first sector gear 202 and the second sector gear 603 respectively, changing the direction of motion transmission. At the same time, the transmission ratio can be adjusted by the gear ratio to achieve a labor-saving effect. The second sector gear 603 accurately transmits the rotational motion of the first sector gear 202 to the second sector gear 603 by meshing with the central gear 4, realizing the transmission of power from the ratchet 2 to the trimmer scissors 6, driving the trimmer scissors 6 to rotate around the rotation center, thereby driving the blade to close. The support arm 5 is equipped with a pawl mechanism 7 that engages with the second ratchet tooth 604. The pawl mechanism 7 locks the pruning shears 6 in one direction by engaging with the second ratchet tooth 604 in one direction, preventing the pruning shears 6 from retracting in the opposite direction due to the reaction force of the branch when cutting the branch, ensuring that the cutting action is continuous and effective, and avoiding insufficient cutting force that prevents the branch from being cut off.

[0026] The second pawl mechanism 7 includes a pawl 701 and a second pawl 702. In this embodiment, the second pawl 702 is used to directly engage with the second ratchet tooth 604 of the trimmer scissors 6 to achieve anti-reverse locking of the trimmer scissors 6 during the trimming process. The pawl 701 is used to engage and limit the second pawl 702 after the trimmer scissors 6 has finished trimming, so that the second pawl 702 disengages from the second ratchet tooth 604, providing an unlocking condition for the trimmer scissors 6 to reverse and reset to the initial position.

[0027] Specifically, one end of the chuck 701 is rotatably connected to the support arm 5 via a rotating support 7011, and the other end of the chuck 701 is provided with a slot. The rotating support 7011 provides a fixed rotation fulcrum for the chuck 701, and a rotating elastic component 7012 is provided between the chuck 701 and the support arm 5. The rotating elastic component 7012 is preferably a torsion spring and is installed on the rotating support 7011. The two ends of the rotating elastic component 7012 are respectively engaged with the upper parts of the support arm 5 and the chuck 701. The support arm 5 is fixedly connected to... A limiting shaft 7013 is provided to limit the rotation of the pawl 701, so that the pawl 701 is normally kept in the initial position without contacting the second pawl 702, thus avoiding interference with the locking engagement between the second pawl 702 and the second ratchet 604. As the trimmer 6 rotates to trim, the second pawl 702 drives the pawl 701 to rotate away from the limiting shaft 7013 until the second pawl 702 locks with the pawl 701. When unlocking, the torsion spring drives the pawl 701 back to its original position under the reset action, ready for the next cycle. The second pawl 702 is rotatably connected to the support arm 5 near the middle via a second rotatable support 7021. That is, the second rotatable support 7021 serves as the rotation center, and the second pawl 702 is mounted on the support arm 5, so that the second pawl 702 forms a lever structure with the rotation center as the fulcrum. A second rotatable elastic component 7022, which is a torsion spring, is provided between the second pawl 702 and the support arm 5. A fixed shaft 7023 is fixed on the support arm 5, and the torsion spring is sleeved on the second rotatable support 7021. One end of the torsion spring is connected to the fixed shaft 7023, and the other end of the torsion spring is connected to the snap-fit ​​end of the second pawl 702. Under the action of the torsion spring, one end of the second pawl 702 can be engaged and fixed with the second ratchet 604, thereby restricting the second ratchet 604 from rotating in the opposite direction. That is, the trimmer 6 cannot retract during cutting, so as to lock the position of the trimmer 6 in the current cutting state and avoid the blade from retracting and cutting interrupted due to the reaction force of the branch. The other end of the second pawl 702 can be engaged with the slot. After the trimming is completed, the slot of the pawl 701 will engage with this end. The limiting force of the pawl 701 overcomes the pre-tightening force of the second rotational elastic component 7022, locking the second pawl 702 in the position away from the second ratchet 604, so that the trimmer 6 can return to the initial position under the pulling force of the blade reset component 601.

[0028] In this embodiment, the trimmer scissors 6 are fixedly connected to a top plate 606 capable of driving the second pawl 702 into the slot, and an unlocking plate 605 capable of driving the second pawl 702 out of the slot. The top plate 606 is located at the end of the second pawl 604 away from the unlocking plate 605. When the trimmer scissors 6 rotates to the closed state, the top plate 606 drives the second pawl 702 to engage with the slot on the pawl 701. When the trimmer scissors 6 returns to the initial position, the unlocking plate 605 applies pressure to the second pawl 702, causing the second pawl 702 to disengage from the restraint of the pawl 701.

[0029] Example 3: like Figures 7 to 10 As shown, a ratchet-based force-saving mechanism is the same as Embodiment Two, except that: the ratchet mechanism Two 7 includes a fixed plate 703, which is fixedly connected to the support arm 5. The fixed plate 703 has a long pawl 705 that can slide back and forth towards the ratchet tooth Two 604. The fixed plate 703 provides a sliding track for the long pawl 705 to ensure smooth movement. The long pawl 705 engages or disengages from the ratchet tooth Two 604 by sliding: when sliding towards the ratchet tooth Two 604, it engages with the ratchet tooth, locking the trimmer 6; when sliding in the opposite direction, it disengages from the ratchet tooth, unlocking the trimmer 6, adapting to different locking requirements under different working conditions. A spring plate 706 is provided at the end of the long pawl 705 away from the ratchet tooth Two 604. The spring plate 706 is fixedly connected to the support arm 5, and the spring plate 706 abuts against the long pawl 705. The spring plate 706 provides a directional elastic preload to the long pawl 705, continuously pushing the long pawl 705 to engage with the ratchet tooth 604.

[0030] A groove is provided on the fixed plate 703, and a locking slider 707 and an unlocking slider 704 are slidably connected in the groove. In this embodiment, the sliding direction of the locking slider 707 and the unlocking slider 704 is perpendicular to the sliding direction of the long pawl 705. The locking slider 707 and the unlocking slider 704 are fixedly connected to achieve linkage between the two. That is, when the unlocking slider 704 is driven, it synchronously drives the locking slider 707 to slide, ensuring that the unlocking action can be quickly transmitted to the locking slider 707, so as to realize the synchronous unlocking of the long pawl 705.

[0031] A compression spring 708 is provided between the end of the locking slider 707 away from the long pawl 705 and the inner end face of the slide groove. A locking platform 7051 that cooperates with the locking slider 707 is fixedly connected to the long pawl 705. The compression spring 708 provides an elastic preload force to the locking slider 707 toward the long pawl 705, so that the locking slider 707 can extend and stably engage with the locking platform 7051 when there is no external force, thereby limiting and fixing the long pawl 705 that has disengaged from the ratchet tooth 604, and facilitating the retraction of the trimmer 6.

[0032] When the compression spring 708 is in its normal state, it is not compressed by external force. This pushes the locking slider 707 to extend and engage the locking platform 7051 of the long pawl 705, preventing the long pawl 705 from moving towards the second ratchet 604. This keeps the two disengaged, and the trimmer 6 is in a freely rotatable unlocked state, facilitating its return to the initial position. Simultaneously, the unlocking slider 704 extends out of its groove, providing a trigger point for subsequent unlocking actions. In other words, by exposing the unlocking slider 704 and engaging the locking slider 707 with the locking platform 7051, the long pawl 705 is fixed in a position away from the second ratchet 604, ensuring that the trimmer 6 will not be accidentally locked under normal conditions. An unlocking plate 605 is fixedly connected to the trimmer 6, capable of driving the unlocking slider 704 back into its groove. When the trimmer 6 rotates back to its initial position, the unlocking plate 605 rotates and pushes the unlocking slider 704, causing it to retract into the groove. At the same time, it drives the locking slider 707 to disengage from the locking platform 7051, releasing the long pawl 705. Under the action of the spring plate 706, the long pawl 705 slides towards the ratchet 604.

[0033] The locking platform 7051 and the locking slider 707 are respectively provided with matching inclined surfaces. The inclined surface design makes the long pawl 705 slide more smoothly away from the second ratchet 604, and can automatically push the locking slider 707 open and complete the reset locking without additional operation. The fixing plate 703 is provided with a limiting platform 7031 for abutting against the locking platform 7051. The limiting platform 7031 limits the maximum stroke of the long pawl 705 towards the second ratchet 604, preventing it from moving excessively and causing jamming or damage, while ensuring a moderate engagement depth.

[0034] Example 4: like Figures 4 to 6As shown, a high-pole shearing includes a support base 10, which serves as the mounting foundation for the high-pole shearing, supporting all core components and ensuring structural stability. The support base 10 is equipped with a ratchet-based force-saving mechanism as described in Embodiment 2. This mechanism utilizes its unidirectional transmission characteristics to achieve effortless shearing. Specifically, the support arm 5 is fixedly connected to the support base 10. A force-applying reset assembly 101, which is a tension spring, is provided between the support arm 5 and the force-applying mechanism 1. After each force application, the force-applying mechanism 1 is pulled back to its initial position, preparing for the next force application. The force-applying mechanism 1 is preferably a swing plate, which rotates around the connecting axis with the support arm 5. This design is lightweight, has high transmission efficiency, and is easy to manually drive with a rope. A pull rope 9 is connected between the support base 10 and the force-applying mechanism 1 via a pulley. The pulley can change the direction of the pull rope, reducing friction and making operation more effortless. The shear blade 6 has a cutting edge at the end away from the sector gear 603, serving as the direct actuator for the shearing action. A blade holder 8 that mates with the blade is fixedly connected to the support arm 5. A blade reset assembly 601 is provided between the trimmer scissors 6 and the support arm 5 at a position away from the center of rotation. The blade reset assembly 601 is preferably a tension spring, which pulls the trimmer scissors 6 back to its initial position after cutting, facilitating the next cutting.

[0035] Working principle: like Figure 4 and Figure 5 As shown, in this embodiment, during use, the support base 10 is fixed on the support rod, and the operator hangs the blade holder 8 of the high-pole shears on the branch to be pruned. The operator pulls the pull rope 9 on the ground, and the pull rope 9 changes the direction of force through the pulley on the support base 10, driving the force-applying mechanism 1 to rotate around the connection point with the support arm 5, converting the pulling force into the driving force of the mechanism.

[0036] When the force-applying mechanism 1 rotates, it drives the pawl mechanism 3 to move synchronously. When the first pawl 301 disengages from the pawl reset baffle 501, under the pulling force of the pawl elastic component 302, the first pawl 301 rotates and meshes with the ratchet tooth 201. The first pawl 301, through the unidirectional tooth structure of the ratchet tooth 201, drives the ratchet wheel 2 to rotate unidirectionally around the common axis of rotation of the support arm 5 and the force-applying mechanism 1. The sector gear 202 on the ratchet wheel 2 meshes with the central gear 4, driving the central gear 4 to rotate. The central gear 4 meshes with the sector gear 603, driving the trimmer 6 to rotate around the axis of rotation of the support arm 5. At this time, the trimmer 6 rotates in the same direction as the ratchet wheel 2. The trimmer 6 moves away from the blade of the sector gear 603 and closer to the blade holder 8, beginning to apply shearing force to the branches.

[0037] During the rotation of the trimmer scissors 6, its second ratchet 604 rotates synchronously with the blade body; under the pre-tightening force of the second rotating elastic component 7022, the second pawl 702 always fits against the tooth surface of the second ratchet 604. Every time it rotates by one tooth pitch, the second pawl 702 automatically engages in the next ratchet groove, directly locking the second ratchet 604 to prevent the trimmer scissors 6 from retracting and to ensure that the cutting stroke continues to accumulate.

[0038] If a single application of force is insufficient to complete the shearing, continuous shearing can be achieved through a cyclical process of "applying force - resetting - applying force again," as follows: The operator releases the pull rope 9, and the force application and reset component 101 pulls the force application mechanism 1 to rotate in the opposite direction, returning it to the initial position; during this process, the pawl limit block 303 of the pawl mechanism 3 contacts the pawl reset baffle 501 on the support arm 5, and the pawl reset baffle 501 restricts the reset angle of the first pawl 301, causing the first pawl 301 to disengage from the ratchet tooth 201 and return to the initial standby position.

[0039] Then, the force is applied repeatedly: the operator pulls the rope 9 again, and the force application mechanism 1 once again drives the first pawl 301 to engage with the ratchet 201, driving the ratchet 2 to continue rotating in one direction. The trimmer shears 6 continue to move closer to the blade holder 8, causing the shearing force to accumulate continuously. This segmented force application mode significantly reduces the force required for a single operation, achieving the core function of saving effort, until the branch is completely cut off by the shearing pair formed by the blade and the blade holder 8.

[0040] like Figure 6 As shown, after the trimming operation is completed, the blade is fully closed, meaning the trimmer 6 rotates to its maximum stroke. The top plate 606 pushes the second pawl 702 to rotate around the second rotating support 7021, lifting the second pawl 702 so that it engages in the slot of the pawl 701. At this time, the second pawl 702 disengages from the second ratchet 604, and the pawl 701 is limited by the preload of the first rotating elastic component 7012. The blade reset component 601 pulls the trimmer 6 to rotate in the opposite direction, returning it to its initial open state. After the trimmer 6 resets, the unlocking plate 605 impacts the second pawl 702, causing the second pawl 702 to disengage from the slot. The second pawl 702 resets under the action of the second rotating elastic component 7022, re-engaging with the second ratchet 604. The pawl 701 also returns to its standby position under the action of the first rotating elastic component 7012, ready for the next trimming.

[0041] Example 5: like Figures 9 to 11 As shown, a high-branch shear has a ratchet force-saving mechanism as described in Embodiment 3 on the support base 10, and the rest is the same as in Embodiment 4.

[0042] The working principle of this embodiment is the same as above, the difference being: During the rotation of the trimmer scissors 6, the second ratchet 604 rotates synchronously with the blade body; its inclined tooth surface drives the long pawl 705 to slide briefly away from the second ratchet 604. After the tooth surface transitions, under the pushing force of the spring plate 706, the long pawl 705 immediately returns to its original position and always adheres to the tooth surface of the second ratchet 604. With each rotation of one tooth pitch, the long pawl 705 automatically engages in the next ratchet groove, directly locking the second ratchet 604 to prevent the trimmer scissors 6 from retracting and to ensure continuous accumulation of the cutting stroke.

[0043] When trimming is complete and the trimmer 6 rotates to its maximum stroke, the end of the second ratchet 604 lifts the long pawl 705, which slides away from the second ratchet 604. Its locking platform 7051 pushes the locking slider 707 open through the inclined surface that cooperates with the locking slider 707, and the compression spring 708 is compressed. After the locking platform 7051 passes the locking slider 707, the compression spring 708 returns to its original position, pushing the locking slider 707 to re-engage the locking platform 7051. At this time, the long pawl 705 lifts the spring plate 706, and its end disengages from the second ratchet 604, releasing the lock on the rotation direction of the trimmer 6, allowing the trimmer 6 to retract.

[0044] As the pawl mechanism 2 7 is unlocked, the trimmer 6 rotates in the opposite direction and returns to its initial position under the pulling force of the blade reset assembly 601. During this process, the unlocking plate 605 contacts the unlocking slider 704, pushing the unlocking slider 704 back into the groove. Because the locking slider 707 is fixedly connected to the unlocking slider 704, the unlocking slider 704 simultaneously drives the locking slider 707 to disengage from the locking platform 7051. Under the elastic force of the spring plate 706, the long pawl 705 slides towards the ratchet 2 604 until the locking platform 7051 abuts against the limiting platform 7031 of the fixed plate 703. At this time, the long pawl 705 engages with the ratchet 2 604, completing the reset and preparing for the next shearing.

[0045] Finally, although this specification describes embodiments, not every embodiment contains only one independent technical solution. This way of describing the specification is only for clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A ratchet-based force-saving mechanism, characterized in that: It includes a pawl mechanism (3) and a ratchet component (2). The pawl mechanism (3) includes a first pawl (301) and a pawl limiting block (303) on the side of the first pawl (301) away from the engaging part. The ratchet component (2) is provided with a ratchet tooth (201) that can engage with the first pawl (301) and a sector gear (202) on the side of the ratchet component (2) away from the ratchet tooth (201).

2. The ratchet force-saving mechanism according to claim 1, characterized in that: The end of the first ratchet (201) is provided with a ratchet limiting block (203) for engaging and limiting the first pawl (301).

3. The ratchet force-saving mechanism according to claim 2, characterized in that: It also includes a force-applying mechanism (1) and a support arm (5). A pawl mechanism (3) is rotatably mounted on the force-applying mechanism (1), and the force-applying mechanism (1) is located away from the mounting fulcrum of the pawl mechanism (3). A pawl elastic component (302) is provided between the pawl mechanism (3) and the pawl elastic component (3). A ratchet component (2) is rotatably connected to the force-applying mechanism (1) and the support arm (5) respectively. A pawl reset baffle (501) that cooperates with the pawl limit block (303) is fixedly connected on the support arm (5).

4. The ratchet force-saving mechanism according to claim 3, characterized in that: The arm (5) is rotatably connected to a trimmer (6) and a central gear (4). The trimmer (6) is provided with a second ratchet (604) and a second sector gear (603) at one end near the ratchet (2). The second sector gear (603) is connected to the first sector gear (202) through the central gear (4). The arm (5) is provided with a second ratchet mechanism (7) that engages with the second ratchet (604).

5. A ratchet-based force-saving mechanism according to claim 4, characterized in that: The second pawl mechanism (7) includes a pawl (701) and a second pawl (702). One end of the pawl (701) is rotatably connected to the support arm (5), and a rotational elastic component (7012) is provided between the pawl (701) and the support arm (5). The other end of the pawl (701) is provided with a slot. A limiting shaft (7013) for rotating and limiting the pawl (701) is fixedly connected to the support arm (5). The second pawl (702) is rotatably connected to the support arm (5) near the middle, and a rotational elastic component (7022) is provided between the second pawl (702) and the support arm (5). One end of the second pawl (702) can be engaged and fixed with the second ratchet (604), and the other end of the second pawl (702) can be engaged and cooperated with the slot.

6. A ratchet-based force-saving mechanism according to claim 5, characterized in that: Both the first rotating elastic component (7012) and the second rotating elastic component (7022) are torsion springs. The trimmer (6) is fixedly connected to a top plate (606) that can drive the second pawl (702) into the slot and an unlocking plate (605) that can drive the second pawl (702) out of the slot.

7. A ratchet-based force-saving mechanism according to claim 4, characterized in that: The second pawl mechanism (7) includes a fixed plate (703), which is fixedly connected to the support arm (5). The fixed plate (703) is provided with a long pawl (705) that can slide back and forth towards the second ratchet (604). A spring plate (706) is provided at the end of the long pawl (705) away from the second ratchet (604). The spring plate (706) is fixedly connected to the support arm (5), and the spring plate (706) abuts against the long pawl (705). A groove is provided on the fixed plate (703), and a locking slider (707) and an unlocking slider (704) are slidably connected in the groove. The locking slider (707) and the unlocking slider (704) are fixedly connected. A compression spring (708) is provided between the end of the locking slider (707) away from the long pawl (705) and the inner end face of the groove. A locking platform (7051) that cooperates with the locking slider (707) is fixedly connected on the long pawl (705).

8. A ratchet-based force-saving mechanism according to claim 7, characterized in that: When the compression spring (708) is in its normal state, the unlocking slider (704) extends out of the groove, and the locking slider (707) can extend out and be locked and fixed with the locking platform (7051). The trimmer (6) is fixedly connected to an unlocking plate (605) that can drive the unlocking slider (704) to retract into the groove.

9. A ratchet force-saving mechanism according to claim 8, characterized in that: The locking platform (7051) and the locking slider (707) are respectively provided with matching inclined surfaces, and the fixing plate (703) is provided with a limiting platform (7031) for abutting against the locking platform (7051).

10. A high-pole pruning shear, comprising a support base (10), characterized in that: The support base (10) is provided with a ratchet force-saving mechanism as described in any one of claims 4 to 9. The support arm (5) is fixedly connected to the support base (10). A force-applying reset assembly (101) is provided between the support arm (5) and the force-applying mechanism (1). A pull rope (9) is connected between the support base (10) and the force-applying mechanism (1) via a pulley. A blade is provided at the end of the trimmer (6) away from the sector gear (603). A blade holder (8) that cooperates with the blade is fixedly connected to the support arm (5). A blade reset assembly (601) is provided between the position of the trimmer (6) away from the rotation center and the support arm (5).

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