A blade locking structure and a trimming machine

Abstract

This application relates to the field of power tools, specifically disclosing a blade locking structure and a trimming machine. The blade locking structure includes clamping members that hold both sides of a blade on an output shaft, and fasteners that secure the clamping members to the output shaft. A fixing member is provided on one side of the locking member. The fixing member includes a mounting portion and an extension portion, with two or more extension portions, any two of which are non-collinearly arranged. When the fixing member is installed on one side of the locking member, any extension portion is fixedly connected to the clamping member via a connector, and the mounting portion covers the outside of the locking member. The fixing member of this application achieves rigid connection with the clamping member through its multiple non-collinear extension portions and multi-point, multi-angle connections using connectors. During assembly, the assembler does not need to consider the single correspondence between the extension portions and the through holes on the clamping member; they can be arbitrarily paired, facilitating matching and installation and improving installation efficiency.

Description

Technical Field

[0001] This application relates to the field of power tools, specifically to a blade locking structure and a trimming machine. Background Technology

[0002] As a core component of gardening tools such as trimmers and lawnmowers, the reliability of the locking structure of the rotating blade directly affects the equipment's operating efficiency and safety. Existing rotating blades are typically fixed to the output shaft using a "pressure plate clamping + end locking" method. The specific structure generally includes the blade, output shaft, pressure plate, and locking components (such as nuts). The locking components axially fix the pressure plate and blade to the output shaft, achieving power transmission. However, existing technology has the following shortcomings: 1. Trimming machines require frequent switching between clockwise and counterclockwise rotation (e.g., alternating trimming and ditching operations). When cutting weeds, trimming machines are prone to severe vibrations from impacts with hard objects. Existing locking structures mostly rely on single thread preload or simple pressure plate constraints. When the output shaft rotates in both directions or vibrates for a long time, the locking components are prone to loosening due to reverse torque or vibration, causing the blade to slide relative to the output shaft, and even posing a safety hazard of blade falling off.

[0003] 2. During outdoor operations, impurities such as grass clippings, dust, and mud can easily penetrate the connection between the locking components and the output shaft. In existing structures, locking components (such as nuts) are often exposed or only covered by simple protective covers. The accumulation of impurities can easily lead to thread corrosion and jamming, which not only affects the reliability of locking but also increases the difficulty of later maintenance. Utility Model Content

[0004] The purpose of at least one specific embodiment of this utility model is to overcome the defects of the prior art and provide a blade locking structure and a trimming machine.

[0005] To achieve the above objectives, the technical solution adopted by this utility model is as follows: A blade locking structure includes: A clamping element, which passes through the output shaft and clamps the blades on both sides of the output shaft; A locking element, which is fastened to the output shaft and locks the clamping element; One side of the locking member is provided with a fixing member, which includes a mounting part and an extension part. The number of extension parts is two or more, and any two extension parts are arranged in a non-collinear state. When the fastener is installed on one side of the locking member, any extension is fixedly connected to the clamping member through the connector, and the mounting part covers the outside of the locking member.

[0006] Furthermore, the inner side of the mounting part is provided with an opening, and the shape of the inner wall of the opening is adapted to the outer periphery of the locking member; The mounting part is fitted onto the outside of the locking part through an opening, and the inner wall of the opening fits with the outer periphery of the locking part to circumferentially limit the locking part.

[0007] Furthermore, the clamping components include an upper pressure plate and a lower pressure plate that are sleeved on the output shaft and respectively clamp the two sides of the blade; The lower pressure plate has a support part on one side. The support part is sleeved on the outside of the output shaft and supported on the boss side of the output shaft surface. When the locking part is locked on the output shaft, one side of it abuts against the upper pressure plate, so that the upper pressure plate and the lower pressure plate form opposing clamping forces on the blade.

[0008] Furthermore, the upper and lower pressure plates are mutually circumferentially limited, and the upper and / or lower pressure plates are circumferentially limited relative to the output shaft.

[0009] Furthermore, the extension and the upper pressure plate are provided with corresponding through holes. When the fastener is fixedly connected to the clamping member through the connector, the extension and the through holes on the upper pressure plate are fixedly connected through the connector, and the fastener is locked to the upper pressure plate.

[0010] Furthermore, the through hole on the extension is the first through hole, which is an oblong hole, and the through hole on the upper pressure plate is the second through hole. There is more than one second through hole, wherein the area of ​​the first through hole is larger than the area of ​​the second through hole.

[0011] Furthermore, the angle between two adjacent extensions is A, where A is greater than 45 degrees and less than 180 degrees.

[0012] Furthermore, in the upper and lower pressure plates, one has a protrusion and the other has a groove corresponding to the protrusion. The protrusion is embedded in the groove, and the cooperating protrusion and groove are used to restrict the circumferential relative rotation between the upper and lower pressure plates.

[0013] Furthermore, the locking component is a nut, the connecting component is a screw, and the locking component is threadedly engaged with the output shaft.

[0014] The beneficial effects of this utility model are as follows: 1. The fastener of this application achieves rigid connection with the clamping member through multiple non-collinear extensions via a multi-point, multi-angle connecting member. During assembly, the assembler does not need to consider the single correspondence between the extensions and the through holes on the clamping member, and can arbitrarily pair them, facilitating matching and installation and improving installation efficiency. (If the two extensions are collinear, once one through hole cannot be matched for installation, the other collinear through hole also cannot be matched for installation).

[0015] 2. The mounting part of the fastener is designed with an opening that matches the outer circumferential contour of the locking part, and is fitted over the outside of the locking part. Through the tight fit between the inner wall of the opening and the outer contour of the locking part, a direct circumferential constraint force is applied to the locking part, effectively preventing the locking part from rotating or loosening during operation.

[0016] 3. After the fastener is installed, its mounting portion covers the outside of the locking component, forming a physical barrier that isolates the locking component (especially its threaded connection) from the external environment. This structure effectively prevents impurities such as grass clippings, dust, and mud from entering the connection between the locking component and the output shaft (threaded mating area), preventing thread corrosion and jamming caused by the accumulation of impurities.

[0017] Another solution adopted in this application is: a trimming machine, comprising: Connecting rod; A drive assembly, which is mounted at the end of the connecting rod; The output shaft has one end connected to the drive assembly. The blade is mounted on the output shaft; The aforementioned blade locking structure is suitable for securing the blade to the output shaft; The drive assembly includes a motor, a gearbox connected to the motor, and a power output end of the gearbox connected to an output shaft.

[0018] The trimming machine is equipped with the aforementioned blade locking structure, and thus has the technical effects of the aforementioned blade locking structure. Attached Figure Description

[0019] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0020] Figure 1 This is a three-dimensional schematic diagram of the working head in Embodiment 1 of this application.

[0021] Figure 2 This is a schematic diagram of the working head explosion in Embodiment 1 of this application.

[0022] Figure 3 This is a cross-sectional schematic diagram of the working head in Embodiment 1 of this application.

[0023] Figure 4 for Figure 3 A magnified view of a portion of area A.

[0024] Figure 5 This is a schematic diagram of the blade locking structure and blade structure in Embodiment 1 of this application.

[0025] Figure 6 for Figure 5 An explosion diagram.

[0026] Figure 7 This is a schematic diagram of the lower pressure plate structure of the working head in Embodiment 1 of this application.

[0027] Figure 8 This is a schematic diagram of the internal cross-section of the output shaft and the lower pressure plate in Embodiment 1 of this application.

[0028] Figure 9 This is a schematic diagram of the upper pressure plate structure of the working head in Embodiment 1 of this application.

[0029] Figure 10 This is a schematic diagram of the fixing structure of the working head in Embodiment 1 of this application.

[0030] Figure 11 This is a schematic diagram of the assembly of the fastener and the upper pressure plate in Embodiment 1 of this application.

[0031] Figure 12 This is a schematic diagram of the output shaft structure of the working head in Embodiment 1 of this application.

[0032] Figure 13 This is a schematic diagram of the trimming machine in Embodiment 2 of this application. Detailed Implementation

[0033] The technical solution of this utility model will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model. Example 1

[0034] Reference Figure 1 , Figure 2 This embodiment provides a working head 100, which includes a protective cover 120, an output shaft 30, a blade 10 passing through the output shaft 30, and a blade locking structure 20 for fastening the blade 10. The end of the output shaft 30 is connected to a drive assembly, which includes a motor 110 and a gearbox 130 that is poweredly connected to the motor shaft of the motor 110. The power output end of the gearbox 130 is connected to the output shaft 30.

[0035] Reference Figure 3The protective cover 120 is a protective component with an opening 121, used to block debris and foreign objects during operation; the motor 110 is fixed to the outside of the protective cover 120, and its motor shaft is connected to the power input end of the gearbox 130 to provide power; the power output end of the gearbox 130 is connected to the output shaft 30 to realize power transmission and speed regulation; one end of the output shaft 30 is connected to the gearbox 130, and the other end extends through the opening 121 of the protective cover 120 to the inside of the protective cover 120. The blade 10 is sleeved on the output shaft 30 and fixed on the output shaft 30 by the blade locking structure 20; the blade locking structure 20 includes an upper pressure plate 50, a lower pressure plate 40, a locking member 60, a fixing member 70 and a connecting member 90. Through the cooperation of multiple parts, the blade is clamped, prevented from loosening and rotated synchronously. The upper pressure plate 50 and the lower pressure plate 40 can form a clamping member for clamping the blade 10 after clamping each other.

[0036] Reference Figures 4 to 8 The lower pressure plate 40 is sleeved on the output shaft 30, and its inner side is provided with an axially extending planar mating part 403, which mainly realizes the effect of circumferential torque transmission. Specifically, the shape of the planar mating part 403 is perfectly adapted to the torque transmission plane 301 on the outer circumference of the output shaft 30. During assembly, the planar mating part 403 and the torque transmission plane 301 radially abut against each other, forming a circumferential positioning constraint to ensure that the lower pressure plate 40 can rotate synchronously with the output shaft 30.

[0037] The lower pressure plate 40 also has a support part 404 on one side. The support part 404 passes through the opening 121 of the protective cover 120 and extends into the gearbox 130. At the same time, the support part 404 is sleeved on the outside of the output shaft 30 and supported on the boss side of the surface of the output shaft 30, further enhancing the connection stability between the lower pressure plate 40 and the output shaft 30.

[0038] Reference Figures 3 to 10 The lower pressure plate 40 has a boss 401 on the side surface near the blade 10; the upper pressure plate 50 has a corresponding groove 501 on the side surface near the blade 10. The groove 501 is adapted to the shape of the boss 401. In this embodiment, the boss 401 is square. When the lower pressure plate 40 and the upper pressure plate 50 are spliced, the boss 401 extends into the groove 501, and the two form a circumferential limit. As mentioned above, after the lower pressure plate 40 is sleeved on the output shaft 30, it forms a circumferential positioning constraint with the output shaft 30. Therefore, after the lower pressure plate 40 and the upper pressure plate 50 are spliced, the clamping member formed by the lower pressure plate 40 and the upper pressure plate 50 also maintains a circumferential limit with the output shaft 30. The lower pressure plate 40 and the upper pressure plate 50 are clamped on both sides of the blade 10 and rotate synchronously with the output shaft 30.

[0039] Reference Figures 2 to 8When the blade 10 is installed, the inner hole 101 of the blade 10 passes through the output shaft 30 and is sleeved on the outer edge of the boss 401 of the lower pressure plate 40, and its side is in close contact with the support surface 405 of the lower pressure plate 40. During assembly, the upper pressure plate 50 is installed on one side of the blade 10, and the boss 401 of the lower pressure plate 40 is embedded in the groove 501 of the upper pressure plate 50. The lower pressure plate 40 and the upper pressure plate 50 are mutually circumferentially limited and clamped on both sides of the blade 10 to ensure that the blade 10 rotates synchronously with the upper and lower pressure plates (to avoid slippage during cutting).

[0040] Reference Figure 2 , Figure 3 , Figure 4 As shown, the locking member 60 is used to axially fix the upper pressure plate 50, the lower pressure plate 40 and the blade 10 on the output shaft 30. The end of the output shaft 30 away from the gearbox 130 is provided with an external thread section 302. In this embodiment, the locking member 60 is a hexagonal nut with an internal thread that matches the external thread section. It is fixed to the end of the output shaft 30 by threaded engagement and abuts against the side of the upper pressure plate 50 to achieve axial pre-tightening.

[0041] Reference Figure 2 , Figure 3 , Figure 11 The fixing member 70 includes a mounting part 701 and an extension part 702. The mounting part 701 is a cylindrical structure that is sleeved on the outside of the locking member 60. Its inner wall is tightly fitted with the outer surface of the locking member 60, and the axial length of the mounting part 701 is greater than the axial length of the locking member 60, so that the locking member 60 is completely accommodated inside the mounting part 701, forming a closed space to prevent impurities from entering. It should be noted that the inner side of the mounting part 701 has an opening 704. The inner wall of the opening 704 is adapted to the outer peripheral contour of the locking member 60. Since the locking member 60 is implemented as a hexagonal nut in this embodiment, the opening 704 is also a hexagonal opening structure. When the mounting part 701 covers the outside of the locking member 60, after it is fixed relative to the upper pressure plate 50, it provides circumferential limitation for the locking member 60.

[0042] Reference Figure 2 , Figure 3 , Figure 11 , Figure 12The extension 702 extends outward from the outer wall of the mounting part 701 and is fixedly connected to the upper pressure plate 50 via the connector 90. The extension 702 of the fixing member 70 has a first through hole 703, and the upper pressure plate 50 has one or more second through holes 503 at corresponding positions. The connector 90 (in this embodiment, a screw) passes through the first through hole 703 and is then fastened to the second through hole 503, thereby achieving axial positioning and circumferential fixation of the extension 702 and the upper pressure plate 50. Multiple extensions 702 are provided and evenly distributed along the circumference of the fixing member 70. The upper pressure plate 50 has a second through hole 503 corresponding to each extension 702. During assembly, any set of extensions 702 can be selected to connect with the second through holes 503, improving assembly flexibility.

[0043] Because the mounting portion 701 of the fastener 70 has an opening 704 on its inner side, the fastener 70 wraps around the locking member 60 through the opening 704. After the fastener 70 is fixedly connected to the upper pressure plate 50 via the connector 90, the mounting portion 701 of the fastener 70 circumferentially limits the locking member 60 and rotates synchronously with the output shaft 30. Regardless of whether the output shaft 30 rotates in the forward or reverse direction, there is no relative rotation tendency between the locking member 60 and the fastener 70, completely eliminating the risk of loosening caused by bidirectional rotation. At the same time, the tight fit between the mounting portion 701 and the locking member 60 forms a closed space, preventing external impurities from entering the threaded connection between the locking member 60 and the output shaft 30.

[0044] Reference Figure 10 , Figure 11 , Figure 12 The first through hole 703 is a waist-shaped hole extending circumferentially along the extension 702, and its circumferential dimension is larger than the corresponding dimension of the second through hole 503, which can compensate for angular deviations during assembly. An anti-loosening washer 80 is provided on the surface of the first through hole 703 of the extension 702 facing the mounting part 701. The inner hole of the anti-loosening washer 80 is coaxially corresponding to the first through hole 703. The connector 90 passes through the inner hole of the anti-loosening washer 80 and the first through hole 703 in sequence and then connects to the second through hole 503. One side of the anti-loosening washer 80 abuts against the surface of the extension 702, and the other side abuts against the head of the connector 90. Through elastic deformation, a continuous pre-tightening force is generated to prevent the connector 90 from loosening.

[0045] It should be noted that the extension 702 includes at least two parts, and they are arranged in a non-collinear manner. The upper pressure plate 50 also has multiple corresponding second through holes 503. This allows the assembler to avoid considering the single correspondence between the through holes on the two components during assembly, enabling arbitrary pairing and installation, thus improving installation efficiency. (If they are collinear, if one through hole cannot be installed, the other collinear through hole will also be unable to be installed.)

[0046] Furthermore, the first through hole 703 on the extension 702 is configured as an oblong hole, the area of ​​which is larger than the area of ​​the second through hole 503 on the upper pressure plate 50, thereby further reducing assembly errors and facilitating locking.

[0047] The angle A between the two extensions 702 is greater than 45 degrees and less than 180 degrees, preferably 135 degrees. When the angle is around 135 degrees, the oblong holes (first through holes 703) on the two extensions 702 and the four second through holes 503 on the upper pressure plate can always ensure that at least one pair of through holes can be locked together. This not only facilitates assembly but also saves costs to a certain extent by avoiding the need to open more through holes.

[0048] Although there are two extensions 702 in this embodiment, in practice only one extension 702 and the through hole on the upper pressure plate 50 need to be locked to achieve the effect of preventing loosening. The purpose of setting two extensions 702 is to facilitate the extensions 702 to quickly match the second through hole 503 on the upper pressure plate 50.

[0049] Reference Figures 2 to 7 The assembly process of the working head 100 is as follows: the lower pressure plate 40 is fitted into the output shaft 30, so that the planar mating part 403 of the lower pressure plate 40 is aligned with the torque transmission plane 301 of the output shaft 30 (to ensure that there is no slippage in the circumferential torque transmission), and the support part 404 of the lower pressure plate 40 extends into the gearbox 130 through the opening 121 of the protective cover 120 and is pushed to the preset position. The blade 10 is fitted onto the outside of the boss 401 of the lower pressure plate 40, so that the side of the blade 10 is in contact with the support surface 405 of the lower pressure plate 40; the upper pressure plate 50 is installed, so that the groove 501 of the upper pressure plate 50 is engaged with the boss 401 of the lower pressure plate 40, ensuring that the upper pressure plate 50 is in close contact with the side of the blade 10; the locking part 60 (nut) is screwed into the external thread section 302 of the output shaft until it abuts against the side of the upper pressure plate 50, completing the axial pre-tightening; the mounting part of the fixing part 70 is then tightened. 701 is fitted onto the outside of the locking member 60, so that the inner wall of the mounting part 701 fits against the outer surface of the locking member 60. The position of the extension part 702 is adjusted so that it is aligned with the second through hole 503 of the upper pressure plate. An anti-loosening washer 80 is placed at the first through hole 703 of the extension part 702. After the connector 90 is passed through the inner hole of the anti-loosening washer 80 and the first through hole 703 in sequence, it is threadedly connected to the second through hole 503 of the upper pressure plate 50 and tightened to complete the fixing of the fixing member 70 and the upper pressure plate 50.

[0050] After the motor 110 starts, the power is transmitted to the output shaft 30 through the gearbox 130. The output shaft 30 drives the lower pressure plate 40 to rotate through the cooperation of the planar mating part 403 and the torque transmission plane 301. The lower pressure plate 40 drives the upper pressure plate 50 and the blade 10 to rotate synchronously through the fitting structure of the boss 401 and the groove 501, so as to realize the cutting operation.

[0051] When the output shaft 30 rotates clockwise or counterclockwise, the upper pressure plate 50 rotates synchronously with the output shaft 30. The fixing member 70 is fixed to the upper pressure plate 50 through the connecting member 90, and therefore rotates synchronously with the upper pressure plate 50. The mounting part 701 of the fixing member 70 is fitted and constrains the locking member 60, preventing the locking member 60 from loosening due to reverse torque or vibration. At the same time, the anti-loosening gasket 80 pre-tightens the connecting member 90 through elastic deformation, preventing the connection between the fixing member 70 and the upper pressure plate 50 from loosening, forming a double anti-loosening of "structural constraint + elastic pre-tightening".

[0052] The mounting portion 701 of the fastener 70 completely houses the locking member 60, forming a physical barrier that isolates the locking member 60 (especially its threaded connection) from the external environment. This structure effectively prevents impurities such as grass clippings, dust, and mud from entering the connection between the locking member 60 and the output shaft 30 (threaded mating area), preventing thread corrosion and jamming caused by the accumulation of impurities. Example 2

[0053] Reference Figure 13 This embodiment provides an edge trimming machine 200, which includes a connecting rod 210, an operating component 220, and a working head 100 as described in Embodiment 1 above. The working head 100 is mechanically connected to the connecting rod 210.

[0054] Because the trimming machine 200 needs to frequently switch the rotation direction of the blades during trimming, the blades will rotate clockwise / counterclockwise (if trimming along a corner, the blades need to be adjusted in the opposite direction). Through the design of the working head 100 in the above embodiment, the blades do not come loose, avoiding sawtooth deviations on the cutting edge. The fixing part of the working head 100 is covered with a locking part, which, together with the protection of the protective cover 120, can prevent grass clippings and mud from entering, thus solving the problem of thread corrosion caused by exposed nuts in traditional trimming machines.

[0055] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this utility model.

Claims

1. A blade locking structure, comprising: A clamping element, which passes through the output shaft and clamps the two sides of the blade on the output shaft; A locking element, which is fastened to the output shaft and locks the clamping element; The locking member is characterized in that a fixing member is provided on one side, the fixing member includes a mounting part and an extension part, the number of the extension parts is two or more, and any two of the extension parts are arranged in a non-collinear state; When the fixing member is installed on one side of the locking member, any of the extensions is fixedly connected to the clamping member through a connector, and the mounting portion covers the outside of the locking member.

2. The blade locking structure according to claim 1, characterized by The mounting part has an opening on its inner side, and the shape of the inner wall of the opening is adapted to the outer peripheral contour of the locking member; The mounting part is fitted over the outside of the locking member through the opening, and the locking member is circumferentially limited by the cooperation between the inner wall of the opening and the outer peripheral contour of the locking member.

3. The blade locking structure according to claim 1, characterized by The clamping component includes an upper pressure plate and a lower pressure plate sleeved on the output shaft and respectively clamping both sides of the blade; The lower pressure plate has a support portion on one side. The support portion is sleeved on the outside of the output shaft and supported on one side of the boss on the surface of the output shaft. When the locking member is locked on the output shaft, one side of it abuts against the upper pressure plate, so that the upper pressure plate and the lower pressure plate form opposing clamping forces on the blade.

4. The blade locking structure according to claim 3, characterized by The upper pressure plate and the lower pressure plate are mutually circumferentially limited, and the upper pressure plate and / or the lower pressure plate are circumferentially limited relative to the output shaft.

5. The blade locking structure according to claim 3, wherein The extension and the upper pressure plate are provided with corresponding through holes. When the fixing member is fixedly connected to the clamping member through the connector, the extension and the through holes on the upper pressure plate are fixedly connected through the connector, and the fixing member is locked to the upper pressure plate.

6. The blade locking structure according to claim 5, wherein The through hole on the extension is a first through hole, which is an oblong hole. The through hole on the upper pressure plate is a second through hole. There is more than one second through hole, wherein the area of ​​the first through hole is larger than the area of ​​the second through hole.

7. The blade locking structure according to claim 1, wherein The angle between two adjacent extensions is A, where A is greater than 45 degrees and less than 180 degrees.

8. The blade locking structure according to claim 3, wherein The upper pressure plate and the lower pressure plate each have a protrusion on one and a groove corresponding to the protrusion on the other. The protrusion is embedded in the groove, and the protrusion and groove cooperate with each other to restrict the circumferential relative rotation between the upper pressure plate and the lower pressure plate.

9. The blade locking structure according to claim 1, wherein The locking component is a nut, the connecting component is a screw, and the locking component is threadedly engaged with the output shaft.

10. A trimming machine characterized by, include: Connecting rod; A drive assembly, which is mounted at the end of the connecting rod; An output shaft, one end of which is connected to the drive assembly; The blade is mounted on the output shaft; The blade locking structure according to any one of claims 1-9 is adapted to fasten the blade to the output shaft; The drive assembly includes a motor, a gearbox connected to the motor, and the power output end of the gearbox connected to the output shaft.

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