Structure for reducing impact sound of self-locking emergency stop of electric drill gear box

Abstract

The utility model relates to a structure for reducing the self-locking emergency stop impact sound of electric drill gear box, including front shell, power output disc, output shaft, upper impact tooth and lower impact tooth, the lower extreme of output shaft is provided with flat position side, the inner wall of the axle of power output disc is provided with inner hole boss, the side of inner hole boss can be contacted with flat position side, the output shaft can rotate under the drive of power output disc, the upper end of output shaft is fixed with upper impact tooth, lower impact tooth is fixedly installed in the inside of front shell and is opposite to upper impact tooth and sets up, the upper end of output shaft passes through the center of lower impact tooth and both do not contact each other, still including rubber ring, the rubber ring is set on the outside wall of upper impact tooth, and reset spring is arranged between the rubber ring and lower impact tooth. After adopting such scheme, the impact sound produced when electric drill is powered off or emergency stop can be effectively weakened, the wear and tear of electric drill gear box internal parts is slowed down, and the service life of electric drill gear box is prolonged.

Description

Technical Field

[0001] This utility model relates to the field of electric drill gearbox technology, and in particular to a structure for reducing the impact noise of the self-locking emergency stop of an electric drill gearbox. Background Technology

[0002] In the field of power tools, electric drills are widely used in construction, machinery repair, home renovation, and other scenarios. Their performance stability and user experience have always been key areas of research and development in the industry. The gearbox, as the core transmission component of the electric drill, plays a crucial role in power transmission and speed regulation. The self-locking emergency stop function is an important design feature to ensure operational safety—when the electric drill encounters a sudden load or the operator releases the switch, the self-locking mechanism can quickly lock the gearbox, preventing accidental injury due to inertia.

[0003] However, existing electric drill gearboxes commonly exhibit noticeable impact noise during the self-locking emergency stop process. This phenomenon arises because when the drill is powered off or an emergency stop is triggered, the motor and power output disc quickly stop operating. However, due to the rotational inertia of rotating components (such as the chuck counterweight and output shaft), they will continue to rotate for a short period under inertia. At this time, the power output disc, which was originally pushing the self-locking pin, has stopped rotating. This results in relative movement between the output shaft and the self-locking pin, ultimately causing a rigid collision between the self-locking pin and the side of the output shaft or other related components, producing a noticeable impact noise.

[0004] The aforementioned impacts not only produce ear-piercing noise and affect the comfort of the operating environment, but in the long run, high-frequency rigid impacts will also accelerate the wear of parts, reduce the service life of the gearbox, and may even cause a decrease in the overall stability of the electric drill due to the vibration generated by the impact, posing a safety hazard. Utility Model Content

[0005] The technical problem to be solved by this utility model is to provide a structure that reduces the impact noise of the self-locking emergency stop of the electric drill gearbox, which can effectively reduce the impact noise generated when the electric drill is powered off or stopped suddenly, reduce the wear of the internal parts of the electric drill gearbox, and extend the service life of the electric drill gearbox.

[0006] To solve the above-mentioned technical problems, the technical solution provided by this utility model is as follows:

[0007] A structure for reducing the impact noise of a power drill gearbox during self-locking emergency stop includes a front housing, a power output disc, an output shaft, an upper impact tooth, and a lower impact tooth. The power output disc is rotatably mounted at the bottom of the front housing. The lower end of the output shaft is slidably engaged with the axis of the power output disc, and the lower end of the output shaft has a flat side. An inner boss is provided on the inner wall of the axis of the power output disc, and the side of the inner boss can contact the flat side. The output shaft can rotate under the drive of the power output disc. The upper impact tooth is fixedly sleeved on the upper end of the output shaft, and the lower impact tooth is fixedly installed inside the front housing and opposite to the upper impact tooth. The upper end of the output shaft passes through the center of the lower impact tooth, and the two do not contact each other. The structure also includes a rubber ring sleeved on the outer side wall of the upper impact tooth, and a return spring is provided between the rubber ring and the lower impact tooth. Specifically, the lower end of the return spring is fixedly connected to the lower impact tooth, and the lower end of the power output disc is connected to the motor drive end, so the power output disc can only rotate and will not slide axially.

[0008] During operation of the lithium-ion electric drill gearbox, the raised side of the power output disc pushes the self-locking pin, while the inner boss side of the power output disc pushes the flat side of the output shaft, achieving synchronous rotational transmission between the power output disc and the output shaft. When the drill suddenly stops working, the power output disc stops rotating quickly along with the motor; however, the output shaft tends to continue rotating due to inertial force. Since the upper impact tooth and the output shaft are fixedly fitted (or interference fit) together, the output shaft will drive the upper impact tooth to rotate together. However, under the action of the elastic restoring force of the return spring (which plays a supporting and squeezing role), the rubber ring, return spring, and stop plate remain stationary throughout the process. At this time, sliding friction is generated between the stationary rubber ring and the rotating upper impact tooth. This frictional force dampens the output shaft, effectively suppressing its inertial rotation, reducing the output shaft speed, and ultimately reducing the impact noise generated by the flat side of the output shaft hitting the self-locking pin. It should be noted that a bearing is installed above the shift plate and is tightly connected to the output shaft. The shift plate only contacts the outer ring of the bearing and not its inner ring. Since a protective plate is fixedly installed on the top of the front housing, the bearing cannot move outward. Therefore, under the action of the return spring, the bearing and the rubber ring will clamp the shift plate. The shift plate can only move up and down along the output shaft axis when in impact mode.

[0009] The structure of this application effectively reduces the impact noise of the gearbox, and more importantly, it significantly reduces the impact of internal parts on the gearbox, extending the gearbox's lifespan and ensuring operational accuracy. It is worth mentioning that in this application, the return spring not only retains its reset function under impact conditions but also serves to secure the rubber ring.

[0010] Preferably, the system further includes a function switching component, which comprises a stop plate, an adjusting shim, and a function cup. The function cup is rotatably fitted onto the outer wall of the front housing, and a spring is fixedly disposed between the function cup and the outer wall of the front housing. The adjusting shim is fixedly installed on the inner wall of the function cup. One end of the stop plate slides along the axial direction of the output shaft and engages with the adjusting shim, while the other end of the stop plate is fitted onto the outer wall of the upper impact tooth. The rubber ring is pressed and fixed against the stop plate by the push of the return spring. Specifically, although the function cup can rotate outside the front housing, the rotational movement of the function cup is restricted by the spring between them. When it is necessary to switch working modes, the user needs to apply external force to overcome the elastic restoring force of the spring, causing the spring to deform elastically so that the function cup can rotate. This structural design allows the function cup to be reliably positioned in a non-human-operated state, avoiding malfunctions due to vibration or impact during normal operation of the electric drill.

[0011] In summary, this structural design allows the rubber ring to remain relatively stationary at all times without affecting the normal transmission function of the gearbox in each gear position.

[0012] Preferably, the inner diameter of the rubber ring is interference-fitted with the outer wall of the upper impact tooth, and the outer diameter of the rubber ring only contacts the stop plate and the return spring. In this way, the rubber ring will always be tightly fitted to the stop plate under the action of the return spring and cannot rotate. When the motor stops running, because the inner diameter of the rubber ring is interference-fitted with the outer wall of the upper impact tooth and the rubber ring cannot rotate, friction will be generated between the rubber ring and the outer wall of the upper impact tooth to quickly stop the output shaft from rotating, thereby reducing the impact noise.

[0013] Preferably, the device further includes multiple self-locking pins. The upper end of the power output disc has multiple protrusions spaced around its axis, with adjacent protrusions forming receiving grooves. The multiple self-locking pins are respectively disposed within these receiving grooves. In operation, the sidewalls of the self-locking pins abut against the sidewalls of the protrusions and the flat side of the output shaft. Thus, when the motor is running, the power output disc pushes the self-locking pins through the protrusions, and transmits torque through the inner boss engaging with the flat side of the output shaft. When the motor is powered off or stops suddenly, the power output disc stops rotating, while the output shaft continues to rotate due to inertia. At this time, the friction between the rubber ring and the upper impact teeth rapidly reduces the output shaft speed. When the flat side of the output shaft contacts the self-locking pin and abuts against the protrusion of the power output disc, rigid limiting is achieved, completing the locking. The function of the rubber ring is to quickly reduce the impact speed and force during the self-locking process, achieving a smooth stop.

[0014] Preferably, the device further includes a limiting cover, which is fixedly installed inside the front housing. The output shaft passes through the axis of the limiting cover, and the limiting cover covers the self-locking pin. A cover is provided at the upper end of the limiting cover, and the self-locking pin is located between the cover and the power output disc. In this way, the axial movement of the self-locking pin is restricted, allowing it to move horizontally only within the receiving groove of the power output disc.

[0015] In summary, this structure, which reduces the impact noise of the drill gearbox during emergency stop, can effectively reduce the impact noise generated when the drill is powered off or stops suddenly, slow down the wear of internal parts of the drill gearbox, and extend the service life of the drill gearbox. Attached Figure Description

[0016] The present invention will be further described below with reference to the accompanying drawings and specific embodiments:

[0017] Figure 1 This is a schematic diagram of the structure of this utility model;

[0018] Figure 2 This is a cross-sectional view of the present invention. Figure 1 ;

[0019] Figure 3 This is a cross-sectional view of the present invention. Figure 2 ;

[0020] Figure 4 This is a schematic diagram of the structure of the output shaft and the power output disc in this utility model;

[0021] Figure 5 This is a schematic diagram showing the assembly relationship of the output shaft, shift plate, rubber ring, and upper impact tooth in this utility model.

[0022] Figure 6 This is a schematic diagram showing the assembly relationship of the output shaft, shift plate, rubber ring, self-locking pin, and power output disc in this utility model.

[0023] Figure 7 This is an assembly diagram showing the relationship between the spring sheet, the functional cup, and the front shell in this utility model.

[0024] in:

[0025] 1-Front shell;

[0026] 2-Power take-off plate; 21-Inner bore boss; 22-Receiving groove;

[0027] 3-Output shaft; 31-Flat side;

[0028] 4- Upper impact teeth;

[0029] 5-Lower impact tooth;

[0030] 6-Rubber ring;

[0031] 7-Return spring;

[0032] 8-Function switching component; 81-Toggle switch; 82-Adjustment shim; 83-Function cup; 84-Spring;

[0033] 9-Self-locking pin; 91-Limit cover; 911-Cover. Detailed Implementation

[0034] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model.

[0035] In the description of this utility model, it should be understood that the orientation and positional relationship indicated by terms such as "up", "down", "left", "right", "front", "back", "vertical", "bottom", "inner", and "outer" are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description. They are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0036] Reference Figures 1 to 6 As shown, a structure for reducing the impact noise of a drill gearbox during self-locking emergency stop includes a front housing 1, a power output disc 2, an output shaft 3, an upper impact tooth 4, and a lower impact tooth 5. The power output disc 2 is rotatably mounted on the bottom of the front housing 1. The lower end of the output shaft 3 is slidably engaged with the axis of the power output disc 2. The lower end of the output shaft 3 is provided with a flat side 31. An inner hole boss 21 is provided on the inner wall of the axis of the power output disc 2. The side of the inner hole boss 21 can contact the flat side 31. The output shaft 3 can rotate under the drive of the power output disc 2. The upper impact tooth 4 is fixedly sleeved on the upper end of the output shaft 3. The lower impact tooth 5 is fixedly installed inside the front housing 1 and is opposite to the upper impact tooth 4. The upper end of the output shaft 3 passes through the center of the lower impact tooth 5 and the two do not contact each other. It also includes a rubber ring 6, which is sleeved on the outer side wall of the upper impact tooth 4. A return spring 7 is provided between the rubber ring 6 and the lower impact tooth 5. Specifically, the lower end of the return spring 7 is fixedly connected to the lower impact tooth 5, and the lower end of the power output disc 2 is connected to the motor drive end. Therefore, the power output disc 2 can only rotate and will not slide axially.

[0037] During the operation of the lithium-ion electric drill gearbox, the protruding side of the power output disc 2 pushes the self-locking pin 9, while the side of the inner hole boss 21 of the power output disc 2 pushes the flat side 31 of the output shaft 3, realizing synchronous rotational transmission between the power output disc 2 and the output shaft 3. When the drill suddenly stops working, the power output disc 2 stops rotating quickly with the motor; however, the output shaft 3 tends to continue rotating due to inertial force, and because the upper impact tooth 4 and the output shaft 3 are fixedly fitted (or interference fit) together, the output shaft 3 will drive the upper impact tooth 4 to rotate together; however, under the action of the elastic restoring force of the return spring 7 (which plays a supporting and squeezing role), the rubber ring 6, the return spring 7 and the stop plate 81 will remain stationary throughout the process. At this time, sliding friction is generated between the stationary rubber ring 6 and the rotating upper impact tooth 4. This frictional force has a damping effect on the output shaft 3, effectively suppressing its inertial rotation, reducing the speed of the output shaft 3, and ultimately reducing the impact sound generated by the flat side 31 of the output shaft 3 hitting the self-locking pin 9. It should be noted that a bearing is provided above the shift plate 81 and is tightly connected to the output shaft 3. The shift plate 81 only contacts the outer ring of the bearing and not its inner ring. Since a protective plate is fixedly installed on the top of the front housing 1, the bearing cannot move outward. Therefore, under the action of the return spring 7, the bearing and the rubber ring 6 will clamp the shift plate 81. The shift plate 81 can only move up and down along the axial direction of the output shaft 3 when the shift is engaged.

[0038] The structure of this application effectively reduces the impact noise of the gearbox, and more importantly, it significantly reduces the impact of internal parts of the gearbox, extending the gearbox's lifespan and ensuring operational accuracy. It is worth mentioning that in this application, the return spring 7 not only retains its reset function under impact conditions but also serves to fix the rubber ring 6.

[0039] Furthermore, refer to Figure 3 and Figure 7As shown, it also includes a function switching component 8, which includes a shift plate 81, an adjusting shim 82, and a function cup 83. The function cup 83 is rotatably sleeved on the outer wall of the front housing 1. A spring piece 84 is fixedly disposed between the function cup 83 and the outer wall of the front housing 1. The adjusting shim 82 is fixedly installed on the inner wall of the function cup 83. One end of the shift plate 81 slides along the axial direction of the output shaft 3 and engages with the adjusting shim 82. The other end of the shift plate 81 is sleeved on the outer wall of the upper impact tooth 4. The rubber ring 6 is pressed and fixed against the shift plate 81 by the push of the return spring 7. Specifically, although the function cup 83 can rotate outside the front housing 1, the rotational movement of the function cup 83 is restricted by the spring piece 84 disposed between them. When it is necessary to switch working modes, the user needs to apply external force to overcome the elastic restoring force of the spring piece 84, so that the spring piece 84 can be elastically deformed to allow the function cup 83 to rotate. This structural design enables the functional cup 83 to be reliably positioned in non-human operation mode, avoiding malfunctions due to vibration or impact during normal operation of the electric drill.

[0040] In summary, this structural design allows the rubber ring 6 to remain relatively stationary at all times without affecting the normal transmission function of the gearbox in each gear position.

[0041] Furthermore, refer to Figure 3 As shown, the inner diameter of the rubber ring 6 is interference-fitted with the outer wall of the upper impact tooth 4, and the outer diameter of the rubber ring 6 only contacts the stop plate 81 and the return spring 7. In this way, the rubber ring 6 will always be tightly fitted with the stop plate 81 under the action of the return spring 7 and cannot rotate. When the motor stops running, because the inner diameter of the rubber ring 6 is interference-fitted with the outer wall of the upper impact tooth 4 and the rubber ring 6 cannot rotate, friction will be generated between the rubber ring 6 and the outer wall of the upper impact tooth 4 to quickly stop the output shaft 3 from rotating, thereby reducing the impact sound.

[0042] Furthermore, refer to Figure 6 As shown, it also includes multiple self-locking pins 9. Multiple protrusions (not shown in the figure) are spaced around the upper end of the power output disc 2 along its axis, forming receiving grooves 22 between adjacent protrusions. The multiple self-locking pins 9 are respectively disposed within the receiving grooves 22. In the working state, the sidewalls of the self-locking pins 9 abut against the sidewalls of the protrusions and the flat sidewall 31. Thus, when the motor is running, the power output disc 2 pushes the self-locking pins 9 through the protrusions, and transmits torque through the inner hole boss 21 cooperating with the flat sidewall 31 of the output shaft 3. When the motor is powered off or stops suddenly, the power output disc 2 stops rotating, while the output shaft 3 continues to rotate due to inertia. At this time, the friction between the rubber ring 6 and the upper impact tooth 4 rapidly reduces the speed of the output shaft 3. When the flat sidewall 31 of the output shaft 3 contacts the self-locking pin 9 and abuts against the protrusion of the power output disc 2, rigid limiting is achieved, completing the locking. The function of the rubber ring 6 is to quickly reduce the impact speed and force during the self-locking process, achieving a smooth stop.

[0043] Furthermore, refer to Figure 2 and Figure 3 As shown, it also includes a limiting cover 91, which is fixedly installed inside the front housing 1. The output shaft 3 passes through the axis of the limiting cover 91, and the limiting cover 91 covers the self-locking pin 9. A cover 911 is provided at the upper end of the limiting cover 91, and the self-locking pin 9 is located between the cover 911 and the power output disc 2. In this way, the axial movement of the self-locking pin 9 is restricted, so that it can only move horizontally within the receiving groove 22 of the power output disc 2.

[0044] In summary, this structure, which reduces the impact noise of the drill gearbox during emergency stop, can effectively reduce the impact noise generated when the drill is powered off or stops suddenly, slow down the wear of internal parts of the drill gearbox, and extend the service life of the drill gearbox.

[0045] In summary, the above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A structure for reducing the impact noise of a power drill gearbox during self-locking emergency stop, comprising a front housing, a power output disc, an output shaft, an upper impact tooth, and a lower impact tooth. The power output disc is rotatably mounted on the bottom of the front housing. The lower end of the output shaft is slidably engaged with the axis of the power output disc. The lower end of the output shaft has a flat side surface. An inner bore boss is provided on the inner wall of the axis of the power output disc. The side surface of the inner bore boss can contact the flat side surface. The output shaft can rotate under the drive of the power output disc. The upper impact tooth is fixedly sleeved on the upper end of the output shaft. The lower impact tooth is fixedly installed inside the front housing and is opposite to the upper impact tooth. The upper end of the output shaft passes through the center of the lower impact tooth, and the two do not contact each other. It also includes a rubber ring, which is sleeved on the outer wall of the upper impact tooth, and a return spring is provided between the rubber ring and the lower impact tooth.

2. The structure for reducing the impact noise of the electric drill gearbox during emergency stop according to claim 1, characterized in that, It also includes a function switching component, which includes a shift plate, an adjustment shim, and a function cup. The function cup is rotatably sleeved on the outer wall of the front housing. A spring is fixedly disposed between the function cup and the outer wall of the front housing. The adjustment shim is fixedly installed on the inner wall of the function cup. One end of the shift plate slides in cooperation with the adjustment shim along the axial direction of the output shaft. The other end of the shift plate is sleeved on the outer wall of the upper impact tooth. The rubber ring is pressed and fixed against the shift plate by the push of the return spring.

3. The structure for reducing the impact noise of the electric drill gearbox during emergency stop according to claim 2, characterized in that, The inner diameter of the rubber ring is interference-fitted with the outer wall of the upper impact tooth, and the outer diameter of the rubber ring only contacts the stop plate and the return spring.

4. The structure for reducing the impact noise of the electric drill gearbox during emergency stop according to claim 3, characterized in that, It also includes multiple self-locking pins. The upper end of the power output disc is provided with multiple protrusions at intervals around its axis. Adjacent protrusions form receiving grooves. The multiple self-locking pins are respectively disposed in the receiving grooves. In the working state, the sidewall of the self-locking pin abuts against the sidewall of the protrusion and the sidewall of the flat position.

5. The structure for reducing the impact noise of the electric drill gearbox during emergency stop according to claim 4, characterized in that, It also includes a limiting cover, which is fixedly installed inside the front housing. The output shaft passes through the axis of the limiting cover, the limiting cover covers the self-locking pin, and a cover is provided at the upper end of the limiting cover. The self-locking pin is located between the cover and the power output disc.

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