Damping structure of power tool and power tool

Abstract

The utility model discloses a kind of damping structure and electric tool of electric tool, it is related to electric tool field, including output shaft, rotating component and fixed component, the rotating component and the fixed component are all set on the output shaft, the output shaft drives the rotating component relative to the fixed component rotation, the rotating component includes first rotating member;At least one damping member is set on the output shaft, the damping member is circumferentially fixed to the output shaft, and the damping member side is abutting to the fixed component.The damping structure of the utility model has the advantage of accelerating the deceleration of output shaft.

Description

Technical Field

[0001] This utility model relates to the field of power tool technology, specifically to a damping structure for a power tool and a power tool. Background Technology

[0002] Electric drills are the best-selling product in the power tool industry, widely used in construction, decoration, furniture, and many other sectors. The motor is the key component driving the drill. Traditional electric drills mostly use brushed motors, but in recent years, with technological advancements, brushless motors have gradually gained popularity in the drilling field due to their advantages such as high efficiency, long lifespan, and low noise. Brushless motors use an electronic control system to switch current, eliminating friction between the brushes and the rotor, thereby improving the motor's efficiency and reliability.

[0003] Currently, electric drills equipped with brushless motors on the market experience a rapid decrease in rotor speed when suddenly decelerating from high speed due to the magnetic field characteristics of the brushless motor. However, during deceleration, the output shaft and the working head connected to its transmission have significant inertia due to their large mass, resulting in a slower rate of speed reduction compared to the motor. This speed difference causes the output shaft and working head to continue rotating for a certain period after the brushless motor rotor decelerates, leading to a reverse self-locking phenomenon. This generates continuous noise and, in severe cases, can even damage components, significantly shortening the lifespan of the electric drill. Utility Model Content

[0004] This utility model aims to solve one of the technical problems in related technologies to a certain extent. To this end, this utility model provides a damping structure for an electric tool and an electric tool that has the advantage of accelerating output shaft deceleration.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A damping structure for a power tool includes an output shaft, a rotating assembly, and a fixed assembly. The rotating assembly and the fixed assembly are both sleeved on the output shaft. The output shaft drives the rotating assembly to rotate relative to the fixed assembly. The rotating assembly includes a first rotating element. At least one damping element is sleeved on the output shaft. The damping element is circumferentially fixed to the output shaft, and one side of the damping element abuts against the fixed assembly.

[0007] In existing technologies, reverse self-locking refers to a situation where, when the motor rotor decelerates or stops, the inertial torque or external resistance torque of the working head exceeds the braking torque of the motor, causing the transmission system to fail to decelerate normally, or even resulting in the working head driving the motor in reverse. This leads to noise and mechanical vibration in the drill. In this application, at least one damping element is provided on the output shaft, with one side of the damping element pressed against a fixed component. The friction between the damping element and the fixed component accelerates the deceleration of the output shaft, which is fixedly connected to the damping element. That is, during the deceleration of the motor rotor, the damping element reduces the speed difference between the motor rotor and the output shaft (and the working head), preventing reverse self-locking, thereby reducing noise, preventing damage to drill components, and extending the lifespan of the drill.

[0008] Optionally, the fixing assembly includes a first fixing member, a second fixing member, and an adjusting member, wherein the first fixing member and the second fixing member axially clamp one of the damping members, and / or the adjusting member and the first rotating member axially clamp another damping member; the first fixing member, the second fixing member, and the adjusting member are press-fitted together.

[0009] The damping element generates friction between the first fixed member and the second fixed member, and / or between the second fixed member and the first rotating member to produce a damping effect, thereby accelerating the deceleration of the output shaft and thus achieving rapid deceleration of the working head that is connected to the output shaft drive.

[0010] Optionally, the first or second fixing member is radially pressed against the damping member.

[0011] Optionally, the second fixing member has a receiving groove along its circumference for accommodating the damping member. The receiving groove is located at one end of the second fixing member near the first fixing member so that the damping member is pressed against the first fixing member and the second fixing member.

[0012] The receiving groove provides an installation position for the damping component, ensuring that the damping component can be accurately pressed between the first and second fixing components, thus ensuring the stability of the damping component during the operation of the electric drill and preventing displacement due to vibration or rotation, thereby ensuring the reliability of the damping effect.

[0013] Optionally, the first fixing member is a gearbox seat, and the second fixing member is a static impact gear.

[0014] Preferably, the gearbox housing is used as the first fixing member, the static impact gear as the second fixing member, and the damping element is placed between the gearbox housing and the static impact gear and is in a clamping state. When the motor rotor of the electric drill decelerates, the working head and the output shaft still maintain a high speed due to inertia. At this time, the damping element forms resistance on the output shaft, causing its speed to decrease more rapidly, thereby reducing the speed difference between the output shaft and the motor rotor.

[0015] Optionally, there is an installation gap between the adjusting member and the first rotating member, and the damping member is disposed within the installation gap.

[0016] During motor rotor deceleration, the damping element rubs against the adjusting element as it rotates with the output shaft, generating a damping effect that allows the output shaft to decelerate more quickly. Additionally, the damping element absorbs energy, reduces the impact force between the first rotating component and the adjusting element, lowers vibration amplitude, protects the motor and other components from damage, and extends the equipment's service life.

[0017] Optionally, the adjusting component is a shift lever, and the first rotating component is a moving impact gear.

[0018] During deceleration or reversal of an electric drill, the moving impact teeth generate significant impact force due to inertia, leading to increased drill vibration. Damping components can absorb vibration, reduce impact force and vibration amplitude, protect the motor and other components from damage, extend the service life of the equipment, and also reduce the noise generated during drill operation.

[0019] Optionally, the output shaft has a positioning boss formed along its circumference, the moving impact tooth is sleeved on the output shaft and located between the positioning boss and the second fixing member, and the moving impact tooth has a tendency to move away from the first fixing member along the direction of the output shaft.

[0020] The output shaft has a locating boss along its circumference. The moving impact tooth is mounted on the output shaft in a sleeve manner, positioned between the locating boss and the second fixing member. In this structure, the moving impact tooth tends to move away from the first fixing member along with the output shaft. When the power tool is in drilling or screw-driving mode, the moving and stationary impact teeth remain separated, meaning they do not contact each other. In this mode, the machine performs drilling or screw-driving functions without impact. However, when the power tool is switched to impact or hammer mode and begins operation, the operator's pushing action moves the working head and output shaft backward a certain distance, causing the previously separated moving and stationary impact teeth to come into contact, generating impact force to meet the needs of crushing hard materials or performing hammering operations. When the motor stops, the moving impact tooth moves away from the first fixing member along with the output shaft, returning to its initial separated state, preparing for the next impact action. Furthermore, the moving impact tooth is connected to the output shaft with an interference fit, allowing the moving impact tooth to move axially along with the output shaft. The positioning boss has a limiting function to prevent the moving impact teeth from exceeding the safe range during movement, avoid interference or damage with other components, and thus ensure the normal operation of the power tool.

[0021] Optionally, the fixing component includes a bearing, the rotating component includes a second rotating element, the second rotating element being a bushing, and the bearing abuts against the bushing.

[0022] The bearing supports the output shaft, ensuring its smooth and efficient operation. The bushing is mounted on the shaft and rotates with it. The bearing, through its rotatable inner ring, bears the load transmitted by the output shaft, reducing friction during shaft rotation and minimizing energy loss. Simultaneously, the bearing positions and supports the bushing, limiting its axial displacement.

[0023] Optionally, an annular groove is formed on the side surface of the bushing near the output shaft, and the annular groove is filled with a number of steel balls.

[0024] An annular groove is made on the surface of the bushing near the output shaft and filled with steel balls. When the output shaft drives the bushing to rotate, the friction between the surface with the annular groove and the output shaft changes from sliding friction to rolling friction of the steel balls. The frictional force of rolling friction is much smaller than that of sliding friction, thus reducing component wear and improving transmission efficiency.

[0025] Optionally, the damping element is an O-ring.

[0026] O-rings are ring-shaped, simple in structure, and easy to manufacture and install. They are also easy to fit onto shafts, holes, or other components requiring damping, without the need for complex installation structures and tools.

[0027] Optionally, the fixing component includes a bearing, the output shaft is provided with an annular groove, and the damping element is circumferentially fixed in the annular groove and clamped between the annular groove and the bearing.

[0028] This utility model also provides an electric tool, including the aforementioned damping structure. The reasoning process for the beneficial effects of the electric tool provided by this utility model and the aforementioned damping structure is similar, and will not be repeated here.

[0029] These features and advantages of this utility model will be disclosed in detail in the following specific embodiments and accompanying drawings. The preferred embodiments or means of this utility model will be shown in detail in conjunction with the accompanying drawings, but are not intended to limit the technical solutions of this utility model. In addition, each of these features, elements and components appearing in the following text and drawings is multiple and is labeled with different symbols or numbers for convenience, but all represent parts with the same or similar structure or function. Attached Figure Description

[0030] The present invention will be further described below with reference to the accompanying drawings:

[0031] Figure 1 This is a schematic diagram of the electric drill in Embodiment 1 of this utility model;

[0032] Figure 2 for Figure 1 Schematic diagram of the structure at point A;

[0033] Figure 3 This is a partial structural diagram of the electric drill in Embodiment 2 of this utility model;

[0034] Figure 4 This is a partial structural diagram of the electric drill in Embodiment 3 of this utility model.

[0035] Among them, 1. Output shaft; 11. Damping component; 12. Positioning boss; 2. Rotating assembly; 21. First rotating component; 22. Second rotating component; 221. Annular groove; 222. Steel ball; 3. Fixing assembly; 31. First fixing component; 32. Second fixing component; 321. Receiving groove; 33. Adjusting component; 34. Bearing. Detailed Implementation

[0036] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described are intended to explain this utility model and should not be construed as limiting it.

[0037] The terms "an embodiment," "example," or "trademark" used in this specification refer to a particular feature, structure, or characteristic described in connection with the embodiment itself that may be included in at least one embodiment disclosed in this patent. The phrase "in an embodiment" appearing in various places throughout the specification does not necessarily refer to the same embodiment.

[0038] Example 1:

[0039] like Figure 1 and Figure 2 As shown, this embodiment provides a damping structure for a power tool, including an output shaft 1, a rotating component 2, and a fixed component 3. The rotating component 2 and the fixed component 3 are both sleeved on the output shaft 1. The output shaft 1 drives the rotating component 2 to rotate relative to the fixed component 3. The rotating component 2 includes a first rotating element 21. Two damping elements 11 are sleeved on the output shaft 1. The damping elements 11 are circumferentially fixed to the output shaft 1, and one side of the damping element 11 abuts against the fixed component 3.

[0040] In this embodiment, the damping structure of the power tool mainly consists of an output shaft 1, a rotating assembly 2, and a fixed assembly 3. Both the rotating assembly 2 and the fixed assembly 3 are mounted on the output shaft 1, and the output shaft 1 drives the rotating assembly 2 to rotate relative to the fixed assembly 3. Furthermore, the output shaft 1 is connected to the drill bit via a transmission connection. The rotating assembly 2 includes a first rotating member 21, which rotates relative to the fixed assembly 3 under the drive of the output shaft.

[0041] The fixing component 3 includes a first fixing member 31, a second fixing member 32, and an adjusting member 33. The first fixing member 31 and the second fixing member 32 axially clamp a damping member 11, and the adjusting member 33 and the first rotating member 21 axially clamp another damping member 11. The first fixing member 31, the second fixing member 32, and the adjusting member 33 are press-fitted together.

[0042] The fixing assembly 3 includes a first fixing member 31, a second fixing member 32, and an adjusting member 33. The second fixing member 32 and the adjusting member 33 are used to support the output shaft and the rotating assembly 2 on the output shaft, ensuring that the output shaft maintains stable rotation during the operation of the electric drill. In addition, two damping members 11 are sleeved on the output shaft. One damping member 11 is pressed between the first fixing member 31 and the second fixing member 32, and the other damping member 11 is pressed between the adjusting member 33 and the first rotating member 21. Specifically, both damping elements 11 are interference-fitted with the output shaft. One damping element 11 rubs against the first fixed member 31 and the second fixed member 32 during rotation to produce a damping effect, while the other damping element 11 rubs against the adjusting member 33 during rotation to produce a damping effect (at this time, the damping element 11 and the first rotating member 21 rotate simultaneously with the output shaft 1, so they are relatively stationary). This allows the output shaft 1 to decelerate more quickly, reducing the speed difference between the motor rotor and the output shaft 1 (and the working head), preventing reverse self-locking, thereby reducing noise, preventing damage to related components, and extending the service life of the electric drill. In other embodiments, the number of damping elements 11 can also be 3, 4, etc.

[0043] The first fixing member 31 or the second fixing member 32 radially abuts against the damping member.

[0044] The second fixing member 32 has a receiving groove 321 for accommodating the damping member 11 along its circumference. The receiving groove 321 is located at one end of the second fixing member 32 near the first fixing member 31 so that the damping member 11 is pressed against the first fixing member 31 and the second fixing member 32.

[0045] In this embodiment, the second fixing member 32 has a receiving groove 321 along its circumference for accommodating the damping member 11. The receiving groove 321 is located at the end of the second fixing member 32 near the first fixing member 31, and the opening of the receiving groove 321 faces the output shaft 1, so that the damping member 11 can be pressed against the first fixing member 31 and the second fixing member 32. The damping member 11 is placed in the receiving groove 321 of the second fixing member 32. Through the pressing action with the first fixing member 31 and the second fixing member 32, friction is generated during rotation, thereby producing a damping effect on the output shaft 1. During the deceleration process of the electric drill motor, the friction between the damping member 11 and the first fixing member 31 and the second fixing member 32 can reduce the speed of the output shaft 1, reduce the speed difference between the output shaft 1 and the motor rotor, and thus reduce noise.

[0046] The first fixing member 31 is a gearbox seat, and the second fixing member 32 is a static impact gear.

[0047] In this embodiment, the output shaft 1 is connected to the drill bit via a gearbox housing. The gearbox housing contains multiple gears to change the rotational speed and torque of the output shaft 1, adapting to different working requirements. The static impact gear is fixed relative to the gearbox housing and can cooperate with the damping element 11 to generate friction. The damping element 11 is housed between the gearbox housing and the static impact gear, and through its contact with both, it generates friction during rotation, achieving functions such as buffering and noise reduction.

[0048] There is an installation gap between the adjusting member 33 and the first rotating member 21, and the damping member 11 is disposed within the installation gap.

[0049] In this embodiment, the first rotating member 21 rotates under the drive of the output shaft 1. The installation gap is the space reserved between the adjusting member 33 and the first rotating member 21 to accommodate the damping member 11. The size and shape of the installation gap need to be designed according to the size and performance requirements of the damping member 11 to ensure that the damping member 11 can play the role of slowing down the output shaft 1.

[0050] Adjusting component 33 is a shift lever, and first rotating component 21 is a moving impact gear.

[0051] In this embodiment, the moving impact teeth can work in conjunction with the stationary impact teeth. Driven by a motor, the moving impact teeth rotate at high speed or reciprocate, generating impact force through their collision with the stationary impact teeth, thereby assisting the working head in drilling operations. The shift block is supported on the output shaft 1 and located between the moving impact teeth and the bushing. The shift block can rotate relative to the output shaft 1 in the circumferential direction. When the operator moves the shift ring to the drilling or screw stop, the shift ring will cause the shift block to rotate at a certain angle. At this time, the gearbox seat limits the shift block axially, so the output shaft 1 connected to the shift block cannot move axially during operation. Therefore, a certain distance is maintained between the moving and stationary impact teeth, preventing them from contacting each other. Furthermore, when the output shaft 1 rotates, the shift block remains stationary. When the operator moves the shift ring to the impact / hammering position, the shift ring will cause the shift block to rotate again by a certain angle. At this time, the axial limiting groove of the gearbox seat on the shift block is deeper and the distance is greater, meaning that the gearbox seat avoids the shift block by a certain distance. During operation, the output shaft 1 and the shift block can move axially backward a certain distance, causing the moving impact teeth and the stationary impact teeth to contact and generate an impact. When the moving impact teeth directly contact the shift block, a large collision force may be generated, leading to accelerated wear on both. The damping element 11, while reducing noise, also acts as a buffer, reducing the collision force and protecting the surfaces of the shift block and the moving impact teeth.

[0052] The output shaft 1 has a positioning boss 12 formed along its circumference. The moving impact tooth is sleeved on the output shaft 1 and located between the positioning boss 12 and the second fixing member 32. The moving impact tooth has a tendency to move away from the first fixing member 31 as the output shaft 1 moves.

[0053] In this embodiment, the output shaft 1 has a positioning boss 12 along its circumference. The moving impact tooth is mounted on the output shaft 1 in a sleeve manner and is located between the positioning boss 12 and the second fixing member 32. In this structure, the moving impact tooth has a tendency to move away from the first fixing member 31 along with the output shaft 1. When the power tool is in the drilling or screwing mode, the moving impact tooth and the stationary impact tooth remain separated, that is, they do not come into contact. In this mode, the machine is used to perform drilling or screwing functions without impact action. When the power tool is switched to the impact or hammering mode and starts working, under the operator's pushing action, the working head and the output shaft 1 will move backward a certain distance, causing the originally separated moving impact tooth and the stationary impact tooth to come into contact with each other, thereby generating impact force to meet the needs of crushing hard materials or performing hammering operations. When the motor stops running, the moving impact tooth will move away from the first fixing member 31 along with the output shaft 1, returning to the initial separated state, preparing for the next impact action. Furthermore, the moving impact tooth is connected to the output shaft 1 by an interference fit, and the moving impact tooth moves axially along with the output shaft 1. The positioning boss 12 has a limiting function to prevent the moving impact tooth from exceeding the safe range during movement, avoiding interference or damage to other components, thereby ensuring the normal operation of the power tool.

[0054] The fixed component 3 includes a bearing 34, and the rotating component 2 includes a second rotating member 22, which is a bushing, and the bearing 34 abuts against the bushing.

[0055] In this embodiment, the bearing 34 supports the output shaft 1 and ensures its smooth and efficient operation. The bushing is mounted on the shaft and rotates with it. The bearing 34 bears the load transmitted by the output shaft 1 through its rotatable inner ring, reducing friction during the rotation of the output shaft 1 and minimizing energy loss. Simultaneously, the bearing 34 positions and supports the bushing, limiting its axial displacement.

[0056] An annular groove 221 is provided on the side surface of the bushing near the output shaft 1, and the annular groove 221 is filled with a number of steel balls 222.

[0057] In this embodiment, an annular groove 221 is formed on the side surface of the bushing near the output shaft 1. The size of the annular groove 221 is designed according to the diameter and number of steel balls 222 to ensure that the steel balls 222 can roll freely in the groove and will not easily fall out.

[0058] Damping element 11 is an O-ring.

[0059] In this embodiment, the damping element 11 is an O-ring. O-rings are typically made of elastic materials such as rubber or silicone. As a damping element 11, they primarily rely on the elastic deformation of the material to absorb and dissipate energy, thereby achieving vibration reduction and noise reduction. O-rings are ring-shaped, have a simple structure, and are easy to process and install. They are also easy to fit onto shafts, holes, or other components requiring damping, without the need for complex installation structures and tools.

[0060] This embodiment also provides a power tool, including the aforementioned damping structure.

[0061] Example 2:

[0062] like Figure 3 As shown, this embodiment provides a damping structure for a power tool, which is basically the same as that in embodiment 1. The difference is that a damping element 11 is sleeved on the output shaft 1, and the first fixing element 31 and the second fixing element 32 axially clamp the damping element 11.

[0063] In this embodiment, the output shaft 1 has only one damping element 11 between the first fixing member 31 and the second fixing member 32. This design simplifies the structure, reduces the number of parts, and reduces assembly complexity to a certain extent. The damping element 11 is confined between the first fixing member 31 and the second fixing member 32, which can more directly reduce noise on the output shaft 1 within this specific range.

[0064] Example 3:

[0065] like Figure 4 As shown, this embodiment provides a damping structure for a power tool, which is basically the same as that in embodiment 1. The difference is that a damping element 11 is sleeved on the output shaft 1, and the adjusting element 33 and the first rotating element 21 axially clamp the damping element 11.

[0066] In this embodiment, the output shaft 1 has only one damping element 11 between the adjusting member 33 and the first rotating member 21. The single damping element 11 makes the overall damping structure simpler, reduces the number of parts, and lowers the complexity and cost of assembly. At the same time, it also simplifies subsequent maintenance and repair work.

[0067] Example 4:

[0068] This embodiment provides a damping structure for a power tool, which is basically the same as that in Embodiment 1. The difference is that the fixing component includes a bearing 34, the output shaft 1 is provided with an annular groove (not shown in the figure), and the damping element 11 is circumferentially fixed in the annular groove and sandwiched between the annular groove and the bearing 34.

[0069] The above are merely specific embodiments of this utility model, but the scope of protection of this utility model is not limited thereto. Those skilled in the art should understand that this utility model includes, but is not limited to, the contents described in the accompanying drawings and the specific embodiments above. Any modifications that do not depart from the functional and structural principles of this utility model will be included within the scope of the claims.

Claims

1. A damping structure for a power tool, comprising an output shaft, a rotating assembly, and a fixed assembly, wherein the rotating assembly and the fixed assembly are both sleeved on the output shaft, and the output shaft drives the rotating assembly to rotate relative to the fixed assembly, characterized in that, The rotating assembly includes a first rotating member; at least one damping member is sleeved on the output shaft, the damping member is circumferentially fixed to the output shaft, and one side of the damping member abuts against the fixing assembly.

2. The damping structure of a power tool according to claim 1, characterized in that, The fixing assembly includes a first fixing member, a second fixing member, and an adjusting member. The first fixing member and the second fixing member axially clamp one of the damping members, and / or the adjusting member and the first rotating member axially clamp another damping member. The first fixing member, the second fixing member, and the adjusting member are press-fitted together.

3. The damping structure of a power tool according to claim 2, characterized in that, The second fixing member has a receiving groove along its circumference for accommodating the damping member. The receiving groove is located at one end of the second fixing member near the first fixing member so that the damping member is pressed against the first fixing member and the second fixing member.

4. The damping structure of a power tool according to claim 2, characterized in that, The first fixing member is a gearbox seat, and the second fixing member is a static impact gear.

5. The damping structure of a power tool according to claim 2, characterized in that, The adjusting component is a shift lever, and the first rotating component is a moving impact gear.

6. The damping structure of a power tool according to claim 5, characterized in that, The output shaft has a positioning boss along its circumference. The moving impact tooth is sleeved on the output shaft and located between the positioning boss and the second fixing member. The moving impact tooth has a tendency to move away from the first fixing member as the output shaft moves.

7. The damping structure of a power tool according to claim 1, characterized in that, The fixed component includes a bearing, and the rotating component includes a second rotating element, which is a bushing, and the bearing abuts against the bushing.

8. The damping structure of a power tool according to claim 7, characterized in that, The bushing has an annular groove on the side surface near the output shaft, and the annular groove is filled with several steel balls.

9. The damping structure of a power tool according to claim 1, characterized in that, The damping element is an O-ring.

10. The damping structure of a power tool according to claim 1, characterized in that, The fixing assembly includes a bearing, the output shaft is provided with an annular groove, and the damping element is circumferentially fixed in the annular groove and clamped between the annular groove and the bearing.

11. A power tool, characterized in that, Includes the damping structure as described in any one of claims 1 to 10.

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