Impact unloading device and grass trimmer

Abstract

The utility model relates to the field of gardening tools, and discloses an impact unloading device and a grass trimmer, the impact unloading device comprises a rotating assembly, a blade, a buffer assembly and an output shaft, the output shaft is simultaneously connected with and drives the rotating assembly and the buffer assembly to rotate, the blade is located between the rotating assembly and the buffer assembly in the axial direction, and the buffer assembly comprises a first connecting piece and an elastic piece. The first connecting piece is suitable for abutting against the blade and is in axial sliding connection with the blade, and the elastic piece elastically abuts against the first connecting piece in the axial direction, so that the first connecting piece and the rotating assembly clamp the blade and drive the blade to rotate. When the blade is subjected to impact or large resistance, the first connecting piece is matched with the elastic piece, the impact force of the blade is transmitted to the first connecting piece, the first connecting piece axially moves to be far away from the blade and extrudes the elastic piece, and by weakening the clamping effect on the blade, the blade slips and idles in an expanded gap between the rotating assembly and the buffering assembly; therefore, impact force is unloaded, the rotating speed of the blade is slowed down, and damage to the blade and a machine body is reduced.

Description

Technical Field

[0001] This utility model relates to the field of garden tool technology, specifically to an impact unloading device and a lawn mower. Background Technology

[0002] A lawnmower, as a grass-cutting tool, allows users to remove weeds and mow lawns. In existing lawnmowers, the body and blades of the trimmer head are locked in the axial direction. When the blades are impacted or encounter significant resistance, the impact force is transmitted to the body, causing easily breakable parts such as the casing, grip, and operating handle to break. Therefore, this application proposes an impact unloading device and a lawnmower to solve the existing problems. Utility Model Content

[0003] To address at least one of the aforementioned problems, this invention first provides an impact unloading device, comprising a rotating assembly, a blade, a buffer assembly, and an output shaft. The output shaft connects both the rotating assembly and the buffer assembly and drives them to rotate. The blade is axially positioned between the rotating assembly and the buffer assembly. The buffer assembly includes a first connector and an elastic member. The first connector is adapted to abut against the blade and slide axially with it. The elastic member elastically abuts against the first connector, causing the first connector and the rotating assembly to clamp the blade and drive it to rotate. When the working impact of the blade is too great or encounters resistance, the blade vibrates and squeezes the first connector. The first connector slides axially away from the blade and squeezes the elastic member, weakening the clamping effect on the blade and causing it to slip and spin freely, thus unloading the impact force.

[0004] Optionally, the buffer assembly further includes a second connector, the output shaft is connected to the second connector and drives the second connector to rotate, and the first connector and the second connector are axially slidably connected.

[0005] Optionally, a receiving cavity is formed between the first connector and the second connector, and the elastic element is accommodated in the receiving cavity. The elastic element is a spring, and the two ends of the spring abut against the first connector and the second connector, respectively.

[0006] Optionally, the first connector is provided with a first receiving groove, the second connector is provided with a second receiving groove, the receiving cavity is formed by the first receiving groove and the second receiving groove covering each other, the outer side wall of the first receiving groove is located outside the outer side wall of the second receiving groove, or the outer side wall of the second receiving groove is located outside the outer side wall of the first receiving groove.

[0007] Optionally, the bottom of the output shaft is threaded with a locking member, and the upper and lower ends of the second connector respectively abut against the rotating assembly and the locking member to fix the position of the second connector in the axial direction.

[0008] Optionally, the upper end of the second connector is provided with a first protrusion, and the upper end of the first connector is provided with a limiting part. The limiting part is provided with an installation port. The limiting part is sleeved on the first protrusion through the installation port. The bottom of the limiting part abuts against the second connector to limit the downward movement distance of the first connector.

[0009] Optionally, the side wall of the first protrusion is provided with a mounting groove, in which a limiting ring is installed. The limiting ring protrudes radially from the mounting groove and is adapted to abut against the upper end wall of the limiting part.

[0010] Optionally, the rotating assembly includes a mounting base, the output shaft is connected to the mounting base and drives the mounting base to rotate, the bottom of the mounting base is provided with a second protrusion, the blade is sleeved on the second protrusion and is adapted to slide axially with the second protrusion, the mounting base and the first connecting member clamp the blade and drive the blade to rotate.

[0011] Optionally, the rotating assembly further includes a separator plate, which is sleeved on the second protrusion. The separator plate is used to separate the mounting base and the blade. The mounting base and the blade clamp the separator plate and drive the separator plate to rotate. The upper and lower ends of the blade abut against the separator plate and the first connector, respectively.

[0012] Compared to existing technologies, the impact unloading device in this invention uses a rotating component and a buffer component to clamp the blade, thereby driving the blade to rotate. When the blade is subjected to impact or significant resistance, the first connecting member and the elastic member cooperate to transfer the impact force of the blade to the first connecting member. The first connecting member moves axially away from the blade and squeezes the elastic member, thereby reducing the clamping effect on the blade and causing the blade to slip and spin freely in the expanded gap between the rotating component and the buffer component. This unloads the impact force, slows down the blade's rotation speed, and reduces damage to the blade and the machine body.

[0013] In addition, this utility model provides a lawn mower, including the impact unloading device described above.

[0014] Compared with the prior art, the grass cutter described in this utility model has the same advantages as the impact unloading device mentioned above, which will not be repeated here. Attached Figure Description

[0015] Figure 1 This is a structural diagram of the impact unloading device according to an embodiment of the present utility model;

[0016] Figure 2 This is a cross-sectional view of the impact unloading device according to an embodiment of the present utility model;

[0017] Figure 3 for Figure 2 Enlarged view of section A in the middle;

[0018] Figure 4 This is a structural diagram of the output shaft according to an embodiment of the present invention;

[0019] Figure 5 This is a structural diagram of the first connecting member according to an embodiment of the present utility model;

[0020] Figure 6 This is a structural diagram of the second connector according to an embodiment of the present utility model;

[0021] Figure 7 This is a structural diagram of the mounting base according to an embodiment of the present utility model.

[0022] Explanation of reference numerals in the attached figures:

[0023] 1. Buffer assembly; 11. First connector; 111. First receiving groove; 112. Limiting part; 113. Mounting port; 114. Machining groove; 12. Second connector; 121. Second receiving groove; 122. First protrusion; 123. Mounting groove; 124. Limiting ring; 125. Mounting cavity; 13. Spring; 2. Blade; 3. Rotating assembly; 31. Mounting base; 311. Second protrusion; 32. Divider plate; 321. Flange; 4. Output shaft; 5. Locking part; 6. Housing. Detailed Implementation

[0024] To make the above-mentioned objectives, features and advantages of this utility model more apparent and understandable, the specific embodiments of this utility model will be described in detail below with reference to the accompanying drawings.

[0025] The accompanying drawings of the embodiments of this utility model provide a coordinate system XY, where the positive direction of the X-axis represents the left, the negative direction of the X-axis represents the right, the positive direction of the Y-axis represents the top, and the negative direction of the Y-axis represents the bottom.

[0026] This utility model embodiment provides an impact unloading device, combined with Figures 1 to 7As shown, the assembly includes a rotating component 3, a blade 2, a buffer component 1, and an output shaft 4. The output shaft 4 connects both the rotating component 3 and the buffer component 1 and drives them to rotate. The blade 2 is axially located between the rotating component 3 and the buffer component 1. The buffer component 1 includes a first connecting member 11 and an elastic member. The first connecting member 11 is adapted to abut against the blade 2 and slide axially with the blade 2. The elastic member elastically abuts against the first connecting member 11 axially, causing the first connecting member 11 and the rotating component 3 to clamp the blade 2 and drive the blade 2 to rotate. When the working impact of the blade 2 is too large or it encounters resistance, the blade 2 vibrates and squeezes the first connecting member 11. The first connecting member 11 slides axially away from the blade 2 and squeezes the elastic member. The clamping effect on the blade 2 weakens, causing it to slip and spin freely, thus unloading the impact force.

[0027] like Figure 5 As shown, in this embodiment, the output shaft 4 is connected to a drive device (not shown, such as a motor) to provide rotational power. The output shaft 4 passes through the rotating assembly 3, the blade 2, and the buffer assembly 1. The first connecting member 11 has a plurality of machining grooves 114 circumferentially provided on the end face of the blade 2. The machining grooves 114 are used to reduce the contact area of ​​the upper end face of the first connecting member during the manufacturing process, thereby facilitating the control of flatness and reducing the vibration of the first connecting member 11 during operation.

[0028] When the blade 2 is subjected to resistance or a large impact force, an impact force of an uncertain angle will be generated depending on factors such as the direction of the handheld machine, the angle of plant growth, and the position of the obstacle. The axial component of the impact force will cause the first connecting piece 11 to vibrate along the axis. If the radial component of the impact force is less than the static friction between the blade 2 and the first connecting piece 11, the blade 2 will move normally. If it is greater than the maximum static friction, the blade 2 will slip.

[0029] Optionally, the buffer assembly 1 further includes a second connector 12, the output shaft 4 connects to the second connector 12 and drives the second connector 12 to rotate, and the first connector 11 and the second connector 12 are axially slidably connected.

[0030] like Figure 3 , 4 As shown in Figures 6 and 7, in this embodiment, the output shaft 4 and the second connecting member 12 are connected by a spline. The output shaft 4 is provided with a toothed protrusion, and the second connecting member 12 is provided with a toothed groove that matches the toothed protrusion.

[0031] Optionally, a receiving cavity is formed between the first connector 11 and the second connector 12, and the elastic element is accommodated in the receiving cavity. The elastic element is a spring 13, and the two ends of the spring 13 abut against the first connector 11 and the second connector 12, respectively.

[0032] like Figure 3 As shown, in this embodiment, the spring 13 is always in a compressed state and applies a thrust to the first connecting member 11, while the second connecting member 12 drives the first connecting member 11 to rotate together through the spring 13.

[0033] Optionally, the first connector 11 is provided with a first receiving groove 111, and the second connector 12 is provided with a second receiving groove 121. The receiving cavity is formed by the first receiving groove 111 and the second receiving groove 121 covering each other. The outer side wall of the first receiving groove 111 is located outside the outer side wall of the second receiving groove 121, or the outer side wall of the second receiving groove 121 is located outside the outer side wall of the first receiving groove 111.

[0034] like Figure 3 and 6 As shown, in this embodiment, the outer wall of the first receiving groove 111 is located outside the outer wall of the second receiving groove 121. This arrangement not only completely accommodates the spring 13 in the receiving cavity, but also allows the outer wall of the first receiving groove 111 to slide relative to the outer wall of the second receiving groove 121, forming a nested fit. This makes the axial sliding connection between the first connecting member 11 and the second connecting member 12 more stable, and the sliding trajectory is less likely to deviate.

[0035] Optionally, the bottom of the output shaft 4 is threaded with a locking member 5, and the upper and lower ends of the second connecting member 12 abut against the rotating assembly 3 and the locking member 5 respectively to fix the position of the second connecting member 12 in the axial direction.

[0036] like Figure 3 As shown, in this embodiment, the locking member 5 is a nut, and the bottom of the output shaft 4 is threaded. The locking member 5 is connected to the bottom of the output shaft 4 and restricts the downward movement of the second connecting member 12. The bottom of the second connecting member 12 is recessed with a mounting cavity 125, and the locking member 5 is accommodated in the mounting cavity 125, making the structure more compact. In other embodiments, a pin can be used to fix the second connecting member 12 and the output shaft 4.

[0037] like Figure 3 , 5As shown in Figure 6, optionally, the upper end of the second connecting member 12 is provided with a first protrusion 122, and the upper end of the first connecting member 11 is recessed with a limiting part 112. The limiting part 112 is provided with an installation port 113. The limiting part 112 is sleeved on the first protrusion 122 through the installation port 113. The bottom of the limiting part 112 is adapted to abut against the second connecting member 12 to limit the downward movement distance of the first connecting member 11. The end of the limiting part 112 near the drive shaft is provided with a downward protrusion. When the first connecting member 11 moves downward, the protrusion first abuts against the second connecting member 12 to limit the movement, thereby reducing the wear area of ​​the limiting part 112.

[0038] Optionally, a mounting groove 123 is provided on the side wall of the first protrusion 122, and a limiting ring 124 is installed in the mounting groove 123. The limiting ring 124 protrudes radially from the mounting groove 123 and is adapted to abut against the upper end wall of the limiting part 112.

[0039] like Figure 3 and 6 As shown, in this embodiment, the limiting ring 124 is a retaining ring or a silicone ring, etc. The vertical cross-section of the mounting groove 123 is arc-shaped, and the vertical cross-section of the limiting ring 124 is circular. This allows the radial portion of the limiting ring 124 to protrude from the mounting groove 123 when it is installed in the mounting groove 123, thereby abutting against the limiting part 112. Because the limiting part 112 is recessed downward from the upper end of the first connecting member 11, an accommodating space is formed between the upper end of the limiting part 112 and the mounting seat 31 of the rotating assembly 3. Both the limiting ring 124 and the mounting groove 123 are located in the accommodating space, making the structure more compact.

[0040] When the blade 2 wears out due to prolonged use, the user needs to replace it. The specific replacement method is as follows: Rotate the locking member 5 to release the connection between the locking member 5 and the output shaft 4. At this time, the bottom of the second connecting member 12 loses the restraint of the locking member 5. Under the action of the spring 13, the second connecting member 12 will move away from the first connecting member 11 until the limiting ring 124 abuts against the upper wall of the limiting part 112, thus playing a buffering and limiting role, preventing the second connecting member 12 from flying off directly. Then, remove the first connecting member 11, the spring 13, and the second connecting member 12 together from the output shaft 4, and the blade 2 can be removed for replacement.

[0041] Optionally, the rotating assembly 3 includes a mounting base 31, the output shaft 4 is connected to the mounting base 31 and drives the mounting base 31 to rotate, the bottom of the mounting base 31 is provided with a second protrusion 311, the blade 2 is sleeved on the second protrusion 311 and is adapted to slide axially with the second protrusion 311, the mounting base 31 and the first connecting member 11 clamp the blade 2 and drive the blade 2 to rotate.

[0042] like Figure 3 and 7 As shown, in this embodiment, the output shaft 4 and the mounting base 31 are also connected by a spline. The output shaft 4 has protruding teeth, and the mounting base 31 has toothed grooves that match the protruding teeth. A limiting step is formed between the second protrusion 311 and the base of the mounting base 31, and the blade 2 is installed in the limiting step. The upper end of the first protrusion 122 abuts against the lower end of the second protrusion 311 to restrict the upward movement of the second connecting member 12. The mounting base 31 and the locking member 5 limit the second connecting member 12 from the upper and lower ends, respectively. This arrangement ensures that when the blade 2 is obstructed, only the first connecting member 11 moves axially, rather than the first connecting member 11 and the second connecting member 12 moving axially at the same time, thus ensuring the stability of the structure.

[0043] Optionally, the rotating assembly 3 further includes a separator 32, which is sleeved on the second protrusion 311. The separator 32 is used to separate the mounting base 31 and the blade 2. The mounting base 31 and the blade 2 clamp the separator 32 and drive the separator 32 to rotate. The upper and lower ends of the blade 2 respectively abut against the separator 32 and the first connector 11.

[0044] like Figure 1 and 3 As shown, in this embodiment, the separator 32 can reduce the impact force of the blade 2 on the mounting base 31, thereby protecting the mounting base 31. The upper part of the separator 32 is provided with the housing 6 of the grass trimmer head. The edge of the separator 32 is provided with an annular flange 321 protruding upward. The flange 321 is used to cover the bottom of the housing 6 to prevent the blade 2 from directly contacting and cracking the bottom of the housing 6 when it is subjected to impact and vibration, thus preventing damage to the housing 6.

[0045] Working principle: The mounting base 31 and the second connecting member 12 are fixed in the axial direction. When the blade 2 is working normally, the drive shaft rotates and simultaneously drives the mounting base 31 and the second connecting member 12 to rotate. The spring 13 applies an upward force to the first connecting member 11, causing the first connecting member 11 to cooperate with the mounting base 31 to clamp the blade 2 and the separator 32 simultaneously, causing the blade 2 and the separator 32 to rotate simultaneously, thereby allowing the blade 2 to cut the external plants. When the blade 2 is subjected to a large impact force or resistance, the blade 2 vibrates and presses the first connecting member 11 downward. The first connecting member 11 moves down and presses the spring 13. At this time, the clamping effect on the blade 2 weakens, the gap between the first connecting member 11 and the mounting base 31 increases, and the blade 2 begins to slip and spin, thereby unloading the impact force. After the impact force is unloaded, the spring 13 drives the first connecting member 11 to reset and press the blade 2 again, so that the blade 2 returns to its normal working state.

[0046] Compared to existing technologies, the impact unloading device in this invention uses a rotating assembly 3 and a buffer assembly 1 to clamp the blade 2, thereby driving the blade 2 to rotate. When the blade 2 is subjected to impact or significant resistance, the first connecting member 11 and the elastic member cooperate to transfer the impact force of the blade 2 to the first connecting member 11. The first connecting member 11 moves axially away from the blade 2 and squeezes the elastic member, thereby reducing the clamping effect on the blade 2. This causes the blade 2 to slip and rotate freely in the widened gap between the rotating assembly 3 and the buffer assembly 1, thus unloading the impact force, slowing down the rotation speed of the blade 2, and reducing damage to the blade 2 and the machine body. The structure is compact and ingenious, and it is easy to disassemble and replace the blade 2.

[0047] Another embodiment of this utility model provides a lawn mower, including the impact unloading device described above.

[0048] Similarly, the components included in the "components," "mechanisms," and "devices" of this disclosure can also be flexibly combined. They can be modularly produced according to actual needs and assembled as an independent module; or they can be assembled separately to form a module in this device. The division of the above-mentioned components in this disclosure is only one embodiment for ease of reading and is not intended to limit the scope of protection of this disclosure. Any technical solution that includes the above-mentioned components and has the same function should be understood as an equivalent technical solution of this disclosure.

[0049] In the description of this disclosure, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used 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. Therefore, they should not be construed as limitations on this disclosure.

[0050] Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first," "second," etc., may explicitly or implicitly include at least one of that feature. In the description of this disclosure, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0051] In this disclosure, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this disclosure according to the specific circumstances.

[0052] In this disclosure, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0053] It should be noted that when a component is referred to as "fixed to," "set on," "fixed to," or "mounted on" another component, it can be directly on the other component or there may be an intervening component. When a component is considered to be "connected to another component," it can be directly connected to the other component or there may be an intervening component. Furthermore, when a component is considered to be "fixedly connected" to another component, the connection can be detachable or non-detachable, such as through socketing, snap-fitting, integral molding, welding, etc., which are achievable in conventional technologies and will not be elaborated upon here.

[0054] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0055] The above embodiments are merely illustrative of several implementation methods of this disclosure, and their descriptions are relatively specific and detailed. However, they should not be construed as limiting the scope of the utility model patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the inventive concept of this disclosure, and these modifications and improvements all fall within the protection scope of this disclosure.

Claims

1. A shock unloading device, characterized by, The device includes a rotating assembly (3), a blade (2), a buffer assembly (1), and an output shaft (4). The output shaft (4) connects the rotating assembly (3) and the buffer assembly (1) and drives the rotating assembly (3) and the buffer assembly (1) to rotate. The blade (2) is located axially between the rotating assembly (3) and the buffer assembly (1). The buffer assembly (1) includes a first connector (11) and an elastic element. The first connector (11) is adapted to abut against the blade (2) and slide axially with the blade (2). The elastic element elastically abuts against the first connector (11) axially, so that the first connector (11) and the rotating assembly (3) clamp the blade (2) and drive the blade (2) to rotate. When the working impact of the blade (2) is too large or is subject to resistance, the blade (2) vibrates and squeezes the first connector (11). The first connector (11) slides axially away from the blade (2) and squeezes the elastic element. The clamping effect on the blade (2) is weakened, and it slips and spins freely, unloading the impact force.

2. The shock unloading device of claim 1, wherein The buffer assembly (1) further includes a second connector (12), the output shaft (4) is connected to the second connector (12) and drives the second connector (12) to rotate, and the first connector (11) and the second connector (12) are axially slidably connected.

3. The shock unloading device of claim 2, wherein, A receiving cavity is formed between the first connector (11) and the second connector (12), and the elastic element is accommodated in the receiving cavity. The elastic element is a spring (13), and the two ends of the spring (13) abut against the first connector (11) and the second connector (12) respectively.

4. The shock unloading device of claim 3, wherein, The first connector (11) is provided with a first receiving groove (111), and the second connector (12) is provided with a second receiving groove (121). The receiving cavity is formed by the first receiving groove (111) and the second receiving groove (121) covering each other. The outer side wall of the first receiving groove (111) is located outside the outer side wall of the second receiving groove (121), or the outer side wall of the second receiving groove (121) is located outside the outer side wall of the first receiving groove (111).

5. The shock unloading device of claim 2, wherein, The bottom of the output shaft (4) is threaded with a locking member (5), and the upper and lower ends of the second connecting member (12) abut against the rotating assembly (3) and the locking member (5) respectively to fix the position of the second connecting member (12) in the axial direction.

6. The shock unloading device of claim 2, wherein, The upper end of the second connector (12) is provided with a first protrusion (122), and the upper end of the first connector (11) is provided with a limiting part (112). The limiting part (112) is provided with an installation port (113). The limiting part (112) is sleeved on the first protrusion (122) through the installation port (113). The bottom of the limiting part (112) is adapted to abut against the second connector (12) to limit the downward movement distance of the first connector (11).

7. The shock unloading device of claim 6, wherein, The first protrusion (122) has a mounting groove (123) on its side wall. A limiting ring (124) is installed in the mounting groove (123). The limiting ring (124) protrudes radially from the mounting groove (123) and is adapted to abut against the upper end wall of the limiting part (112).

8. The shock mitigation device of any one of claims 1-7, wherein, The rotating assembly (3) includes a mounting base (31), the output shaft (4) is connected to the mounting base (31) and drives the mounting base (31) to rotate, the bottom of the mounting base (31) is provided with a second protrusion (311), the blade (2) is sleeved on the second protrusion (311) and is axially slidably connected to the second protrusion (311), the mounting base (31) and the first connecting member (11) clamp the blade (2) and drive the blade (2) to rotate.

9. The shock unloading device of claim 8, wherein, The rotating assembly (3) further includes a partition disk (32), which is sleeved on the second protrusion (311). The partition disk (32) is used to separate the mounting base (31) and the blade (2). The mounting base (31) and the blade (2) clamp the partition disk (32) and drive the partition disk (32) to rotate. The upper and lower ends of the blade (2) respectively abut against the partition disk (32) and the first connector (11).

10. A grass trimmer characterized by comprising: Includes the impact unloading device as described in any one of claims 1-9.

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