TW201814130A - Spindle automatic return device with deceleration or speed control - Google Patents

Abstract

Disclosed is a crankshaft automatic reset device with a speed reduction or speed control function, comprising a base, wherein the base is internally provided with: a crankshaft; a propelling element fixed on the crankshaft, with the propelling element having a pushing trajectory; a sliding member, which has a function of receiving the pushing trajectory of the propelling element so as to have a tendency to slide from a first position towards a second position along a displacement path; a reset device, which has a function of returning the sliding member from the second position back to the first position; and at least a first traction portion arranged on the sliding member; and same is provided with a propelling portion, at least one propelling stroke conversion element coupled between the first traction portion and the propelling portion, such that the amount of displacement of the propelling portion with respect to the first traction portion is amplified; and the propelling portion is provided with a damping device, the damping device being used for providing a resistance when the sliding member is returned from the second position back to the first position, and having an emergency braking function. The speed of the automatic reset of the crankshaft can be precisely adjusted by means of a height adjustment device arranged on an inner side face having friction with the damping device.

Description

Automatic shaft returning device with deceleration or speed control function

The invention relates to the technical field of mechanical control, in particular to an automatic homing device for a machine shaft having a function of decelerating or controlling speed.

At present, most door closers installed on the top of the door or ground hinges installed on the bottom of the door are mostly provided in the base with a shaft that can link the door and an oil pressure mechanism that can control the speed of the shaft. When the crankshaft rotates with the opening of the door, the oil pressure mechanism can be linked to cause the oil pressure mechanism to accumulate the preliminary pressure. When the door is released, the preparatory pressure of the hydraulic mechanism can provide resistance to the return rotation of the shaft, so that the door returns to the closed position as the shaft slowly rotates.

The aforementioned hydraulic mechanism is usually provided with an adjustment valve, which can adjust the opening amount of the oil return channel of the hydraulic oil inside the hydraulic mechanism, thereby adjusting the flow rate of the hydraulic oil to adjust the accumulation of the hydraulic oil to form the preparatory pressure. In addition, the speed at which the door can be automatically closed can be controlled.

However, the maximum angle at which the door is opened is between 90 and approximately 180 degrees, so the stroke that the door can drive to rotate the shaft is not long, and the hydraulic mechanism must be in a situation where the rotation stroke of the shaft is not long. In order to make the hydraulic oil accumulate enough to resist the return pressure of the machine shaft, even if the adjustment valve of the oil pressure mechanism is adjusted slightly, the reserve pressure accumulated by the oil pressure mechanism will be greatly changed, making it difficult to precisely adjust the reserve pressure. , And the door is prone to the situation that the closing speed is too slow or too fast.

At present, the hinges or door closers on the market are subject to high pressure operation. If strict quality control is not performed, oil leakage is easy. After a period of use, the high pressure is also likely to damage the oil seal and leak oil, which affects the service life.

The technical problem to be solved is how to control and solve the problem that the door closing speed is too slow or too fast. In view of the shortcomings in the prior art, the present invention provides a machine shaft automatic homing device with a speed reduction or speed control function, which includes a base, and the base is provided with: a machine shaft, a pushing element fixed on the machine shaft, The pushing element has a pushing trajectory; the slider receives the pushing trajectory of the pushing element, and has a tendency to slide along a displacement path from a first position toward a second position; a reset device provides a sliding path for the sliding element; The function of restoring the second position to the first position; at least a first traction part provided on the slider; having a pushing part and at least one pushing stroke conversion element connected between the first pulling part and the pushing part , So that the displacement of the pushing portion relative to the first traction portion is enlarged, and the resistance pressure required by the damping device is also reduced according to the gear ratio;

A damping device is provided on the pushing portion, and the damping device is configured to provide resistance when the slider is restored from the second position to the first position. The damping device includes a rotating shaft provided on the pushing device, and the rotating shaft is provided with a unidirectional wheel; a direction of a rotation path of the unidirectional wheel is the same as a direction in which the second position slides toward the first position. The unidirectional wheel further includes a unidirectional bearing, and the unidirectional bearing is sleeved on the rotating shaft. The damping device generates resistance by friction with at least one inner side surface of the base or a bottom surface of the top cover.

Optionally, at least one set of height adjustment devices is also provided on the inner surface or the bottom surface of the top cover that is in friction with the damping device, and the height adjustment device adjusts the friction between the damping device and the inner surface. To achieve speed control. Optionally, the height adjusting device further includes a screw post fixed on the top cover and a screw cap matched with the screw post, and further includes a height adjusting part, and the screw cap is fixed on the height adjusting part. Optionally, the height adjusting device further includes a limiting device that controls the height of the height adjusting device, and the limiting device reserves a space of a predetermined height for the height adjusting device to change the height. Optionally, the height adjustment devices are multiple groups, and the multiple groups of height adjustment devices can control the return speed of the machine shaft at different angles. Optionally, a groove for eliminating or reducing resistance is provided on a path of the damping device.

The damping device is used to provide resistance when the sliding member is restored from the second position to the first position when the crankshaft is reset to 45 °, and the thrust of the pushing part is equivalent to realize emergency braking. The pushing stroke conversion element is used to reduce the resistance pressure required to be provided by the damping device according to the gear ratio. A second rack is provided on the pushing stroke conversion element; wherein the damping device is provided on the second rack. The second rack extends along the displacement path. The first traction portion includes a first rack, and the first rack extends along the displacement path.

It can be known from the above technical solution that the automatic homing device of the crankshaft with a deceleration or speed control function provided by the present invention can provide a damping device that can be used to provide resistance when the sliding member is restored from the second position to the first position. Structure to achieve the purpose of reducing the automatic homing speed of the above-mentioned automatic homing device of the shaft; the height adjustment device provided on the inner surface friction with the damping device can adjust the displacement of the second rack per second by a small amount, and then precisely adjust the shaft Speed of automatic homing. And to overcome the above-mentioned prior art, slightly adjusting the adjustment valve of the hydraulic mechanism will also cause a large change in the reserve pressure accumulated by the hydraulic mechanism, which makes it difficult to precisely adjust the reserve pressure, and the door is prone to close too slowly. Or it is too fast, and its leakage affects its service life.

In addition, the present invention also has a new function that the prior art does not have: emergency braking, this function is not an improvement of the prior art; during the resetting of the door leaf, after the suspension of the door leaf is suspended, the thrust of the pushing part is equivalent to the static friction resistance of the damping device At this time, when the door is restored, the door will be reset slowly to facilitate users with reduced mobility or need to pass slowly.

In order to more clearly explain the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings in the following description are For some embodiments of the invention, for those of ordinary skill in the art, other drawings can be obtained based on these drawings without paying creative labor.

In order to make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described with reference to the accompanying drawings in the embodiments of the present invention. It is a part of the embodiments of the present invention, but not all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by a person of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

As shown in FIG. 1 to FIG. 5, the present invention provides an automatic positioning device for a crankshaft that includes a speed control function. The base 1 includes a crankshaft 11, a pushing element 20 fixed on the crankshaft 11, and a pushing element. 20 has a pushing trajectory; the slider 4 receives the pushing trajectory of the pushing element 20, and has a tendency to slide along a displacement path from the first position toward the second position; the reset device 3 provides the sliding member 4 with the first The function of returning the two positions to the first position; at least a first traction part 410 provided on the sliding member 4; and at least one pushing stroke conversion element 60 connected between the first traction part 410 and the pushing part 510 so that the pushing part The displacement of 510 relative to the first traction part 410 is enlarged; the pressure required for the rotation reset of the mortgage machine shaft will be relatively lowered according to the gear ratio after pushing the stroke conversion element 60, so under the same load, the damping The resistance pressure required by the device will also be relatively reduced; a damping device 12 is provided on the pushing portion 510, and the damping device 12 is used to provide resistance when the slider is restored from the second position to the first position.

As shown in FIG. 3, FIG. 4, FIG. 6, and FIG. 7, the damping device 12 includes a rotating shaft 121 provided on the pushing portion 510, and the rotating shaft 121 is provided with a one-way wheel 122; The position slides in the same direction toward the first position. As shown in FIGS. 3, 4 and 7, the one-way wheel 122 further includes a one-way bearing 123, and the one-way bearing 123 is sleeved on the rotating shaft 121. The one-way wheel 122 is preferably a rubber wheel. Of course, it can be understood that the present invention is not limited to this, and other unidirectional wheels 122 made of materials that can make functions better or more durable can still implement the present invention.

As shown in FIG. 1 to FIG. 5, FIG. 8, and FIG. 9, the base 1 of the automatic homing device for a crankshaft with a deceleration or speed control function further includes a top cover 10. The damping device 12 can generate friction by friction with the bottom surface of the top cover 10 . As shown in FIG. 10, of course, it can be understood that the damping device 12 can friction with other inner side surfaces of the base 1 and can also generate friction force. As shown in FIG. 10, specifically, for example, the damping device 12 may generate resistance by friction with the bottom surface or the inner surface of the base 1. Of course, it is also possible that the damping device 12 frictionally generates resistance with the bottom surface and the inner surface of the top cover 10 of the base 1 at the same time, or the damping device 12 frictionally generates resistance with the bottom surface and the inner surface of the base 1 at the same time. In short, the present invention can be implemented by the friction generating resistance of at least one inner side surface of the damping device 12 and the base 1.

As shown in FIG. 11 to FIG. 14, a height adjustment device 125 is provided on an inner surface of the damping device that is in friction with the top cover 10, and the height adjustment device 125 adjusts a friction force between the damping device 12 and an inner side surface. The height adjusting device 125 may be provided in a group or more than one group according to actual needs. Multiple sets of height adjustment devices 125 can control the return speed of the machine shaft at different angles. Specifically, as shown in FIG. 11 to FIG. 14, the height adjusting device 125 further includes a screw post 128 fixed on the top cover 10 and a screw cap 129 that cooperates with the screw post, and further includes a height adjusting part 130 to fix the screw cap 129. On the height adjustment mounting portion, the pressure between the height adjustment portion 130 and the damping device is adjusted by turning the screw column 128, so as to adjust the friction force generated by the damping device. As shown in FIGS. 12 and 14, the height adjustment device further includes a limit device 126 that controls the height of the height adjustment device. The limiting device 126 reserves a space of a predetermined height for the height adjustment device 125 to change the height.

As shown in FIG. 3 to FIG. 5, FIG. 8, and FIG. 9, in order to ensure the normal operation in the final stage of door closing, the friction force provided by the damping device 12 needs to be eliminated or reduced. In the present invention, a groove 100 is provided on the path of the damping device 12 to eliminate or reduce resistance. The width of the groove is larger than the width of the one-way wheel 122. The groove is provided with a predetermined length, and the length can be set according to actual conditions. As shown in FIG. 8 and FIG. 9, when the damping device moves back into the groove 100 and resets, the compression between the one-way wheel 122 and the inner side is eliminated or reduced, thereby eliminating or reducing the friction provided by the damping device 12. purpose.

As shown in FIG. 1, FIG. 4, FIG. 8, and FIG. 9, the pushing portion 510 extends and acts on the second rack 52 of the pushing stroke conversion element; wherein the damping device 12 is disposed on the pushing portion 510 or the second rack 52 on. The reset element is preferably an elastic element 3. In a more specific embodiment, the pushing element 20 includes a set of cams 2 provided on the shaft 11 so that the cam 2 rotates coaxially with the shaft 11 and uses the edges of the cam 2 to form a push The pushing track 103 of the sliding member 4 enables the sliding member 4 to slide along the displacement path 104 between the cam 2 and the elastic device 3; the sliding member 4 is slidably disposed on at least the sliding track element 70, and the sliding track element 70 may For the slide bar, the slide base or the pulley, the sliding part 4 is further provided with a guide (slide base) 7 at least penetrating the elastic device 3, and the guide (slide base) 7 is provided between the cam 2 and the elastic device 3. The guide (slide) 7 extends along the displacement path 104, and the slider 4 is slidably disposed on the guide (slide) 7. The first traction portion 410 includes a first rack 41 provided on the slider 4, and the first rack 41 extends along the displacement path 104 on the surface of the slider 4 and the pushing portion 510 extends to act on the first stroke conversion element 60. The two racks 52 extend the second rack 52 along the displacement path 104.

As shown in FIGS. 1 to 5, the cam 2 is capable of driving the slider 4 in the direction of the elastic body 3 along the pushing track 103 along with the crank shaft 11 to drive the second rack 41 via the gear set 6 with the first rack 41. Rack 52. As shown in FIG. 1 to FIG. 5, the elastic device 3 can elastically drive the slider 4 to move in the direction of the cam 2 to carry the first rack 41 through the gear set 6 and the second rack 52 to drive the pushing portion 510 in the reverse direction. In detail, the cam 2 passes the first rack 41, the gear set 6 and the second rack 52 of the slider 4 to drive the damping device 12 forward; the elastic device 3 passes the first rack 41 of the slider 4. The gear set 6 and the second rack 52 reversely drive the damping device 12 back to reset.

When the damping device 12 moves forward when receiving the drive, due to the action of the one-way bearing, the one-way wheel rolls on the inner side without friction; but when the damping device is reset back after receiving the drive, the one-way bearing will not roll at this time. , The one-way wheel will not roll with the bottom or inner side, so friction with the bottom or inner side creates resistance. If there is no height adjustment device between the damping device 12 and the inside surface of the top cover or the inside surface of the base, it can be used as a speed reduction device under the condition of constant friction. A height adjustment device is provided between the inner side surface, and the compression amount between the bottom surface of the top cover or the inner side surface and the one-way wheel can be adjusted by the height adjustment device, thereby changing the pressure, and finally changing the friction force generated by the damping device 12, setting different heights will correspond Different friction forces cause the damping device 12 to have different backward reset speeds, so that the device becomes a speed control device.

The rollers 42 of the cam 2 that can press the pushing element 20 are pivoted on the end of the slider 4 to reduce the friction between the slider 4 and the cam 2 so that the cam 2 and the slider 4 can be smoothly transmitted to each other. The cam 2 of the pushing member 20 is provided with a concave portion 21 for the roller 42 of the slider 4 to be pushed against and positioned, and a convex portion 22 capable of driving the slider 4 to move outward in the direction of the elastic device 3. As shown in FIG. 2a, through the above-mentioned component composition, the crankshaft 11 can be set as the crankshaft, ground hinge, or sky hinge, or the hinge, and the door closer, ground hinge, or sky hinge can be installed on the top or bottom of the door. The elastic device 3 can elastically drive the slider 4 to be displaced to the first position 101 in a normal state, so that the roller 42 of the slider 4 is pushed against the recess 21 of the cam 2. As shown in FIG. 2b, when the door is opened, the cam 2 and the shaft 11 can rotate with the door, so that the convex portion 22 of the cam 2 drives the slider 4 to move toward the elastic device 3 along the pushing track 103, so that The sliding member 4 is moved to the second position 102, so that the sliding member 4 compresses the elastic member 3, so that the elastic member 3 accumulates elastic force; at the same time, the first rack 41 moves toward the elastic member 3 with the sliding member 4, so that the first rack 41 drives the second rack 52 via the gear set 6, thereby driving the one-way wheel 122 of the damping device 12 to roll forward without friction.

As shown in FIG. 1 to FIG. 5, when the door is released, the elastic device 3 immediately releases the compression elastic force, and the elastic member 3 drives the slider 4 to move toward the cam 2, so that the slider 4 is displaced to the first position 101 and the first The rack 41 moves in the direction of the cam 2 with the slider 4, so that the first rack 41 drives the second rack 52 via the gear set 6, and then drives the one-way wheel 122 of the damping device 12 backward with friction to reset . The reset speed of the one-way wheel 122 is limited due to the effect of friction. Therefore, the second rack 52 will slowly move with the one-way wheel 122, so that the second rack 52 will slowly drive the first rack 41 via the gear set 6, so that the slider 4 will slowly push against the cam with the first rack 41 2 and the crankshaft 11 rotate and reset, forcing the door leaf to return to the closed position as the crankshaft 11 slowly rotates.

According to the above, the short-distance rotation stroke of the crankshaft 11 can be converted into the long-distance linear displacement stroke of the second rack 52 by the first rack 41 and the gear set 6, and the height adjustment device is provided on the inner surface friction with the damping device. Compared with the short-distance rotation stroke of the crankshaft 11, the long-distance linear displacement stroke of the second rack 52 and the one-way wheel 122 is obviously easier to make precise displacement adjustment through the height adjustment device. When the door is automatically reset to the closing speed, the friction between the one-way wheel 122 and the inner side can be directly controlled by the height adjustment device 122, so that the displacement of the second rack 52 per second can be adjusted by a small amount, and the machine shaft 11 can be precisely adjusted automatically. Home speed.

The automatic shaft returning device with the function of deceleration or speed control provided by the present invention can be used for a door closer, a ground hinge or a sky hinge, and the door closer, the ground hinge or the sky hinge can be installed on a door piece. After the present invention achieves the deceleration function through the structure, it still needs to achieve the purpose of speed control through parts and structures such as oil cylinders or cylinders, pistons, and flow adjustment devices. However, after achieving the speed control function through the structure, compared with the prior art, components such as oil cylinders, cylinders, pistons, and flow adjustment devices can be omitted, thereby effectively reducing the length of the automatic axis returning device and reducing the size of the automatic axis returning device. Volume, while also significantly reducing the cost of production.

As shown in FIG. 17, in addition, if the door leaf is reset during the door leaf resetting process (when the door leaf resets to 50 ° to 40 °), the door spring is stopped (holding the door leaf for a few seconds with your hand), at this time, the elastic device The thrust transmitted to the pushing part is equivalent to the static friction resistance provided by the damping device. Let go of the door, and the door will slowly reset. Therefore, the automatic homing device of the axle provided with the function of deceleration or speed control provided by the present invention realizes emergency braking. As shown in FIG. 17 to FIG. 18, specifically, when the door piece 110 is opened from 0 ° to 90 °, the one-way wheel of the damping device rolls forward a distance X, and at this time, the thrust of the pushing portion is Y, and the damping The friction provided by the device is W. When the door is reset from 90 ° to 0 °, the thrust Y of the pushing portion decreases with different angles, but the friction force provided by the damping device is W before the unidirectional wheel has entered the groove. As shown in Figures 18 to 19, when the door is reset to 45 °, the one-way wheel also moves X / 2 with friction; at this time, the thrust of the pushing part is about 0.6Y, and the pushing part ’s The thrust is approximately equal to the friction provided by the damping device, that is, 0.6Y≈W; at this time, the thrust of the pushing portion and the friction provided by the damping device cancel each other out. After the door is released, the door will slowly reset. Achieve emergency braking. Specifically, the present invention can be applied to users with reduced mobility or need supervision (for example, the elderly, children, or the disabled). Guardians or other enthusiastic people can use this function to facilitate the slow passage of assisted personnel after the door brakes are urgently stopped. The above data are theoretical values. In actual use, the user can stop the door panel at around 45 ° (50 ° to 40 °) to achieve this emergency braking function. The door panel only needs to be slowly reset to achieve slow passage. the goal of. In the present invention, different operating parameters can be set for the length and depth of the groove and the frictional force of the one-way wheel.

In summary, the automatic homing device for a crankshaft with a deceleration or speed control function provided by the present invention has a damping device structure that can be used to provide resistance when the sliding member is restored from the second position to the first position by providing a pushing portion In order to achieve the purpose of reducing the automatic homing speed of the above-mentioned automatic homing device of the shaft; the height adjustment device provided on the inner surface friction with the damping device can adjust the displacement of the second rack per second by a small amount, and then precisely adjust the automatic Home speed. And to overcome the above-mentioned prior art, slightly adjusting the adjustment valve of the hydraulic mechanism will also cause a large change in the reserve pressure accumulated by the hydraulic mechanism, which makes it difficult to precisely adjust the reserve pressure, and the door is prone to close too slowly. Or it is too fast, and its leakage affects its service life. In addition, the present invention also has a new function that the prior art does not have: emergency braking, this function is not an improvement of the prior art; during the resetting of the door leaf, after the suspension of the door leaf is suspended, the thrust of the pushing part is equivalent to the static friction resistance of the damping device At this time, when the door is restored, the door will be reset slowly to facilitate users with reduced mobility or need to monitor slowly.

In summary, it is only a preferred embodiment of the present invention, and is not intended to limit the present invention. All other equivalent modifications or substitutions made without departing from the spirit disclosed by the present invention shall be included in the patent application described below. Within range.

1‧‧‧ base

10‧‧‧ top cover

100‧‧‧ groove

101‧‧‧ first position

102‧‧‧ second position

103‧‧‧ Push track

104‧‧‧Displacement path

11‧‧‧ Shaft

110‧‧‧ Door

12‧‧‧ damping device

121‧‧‧ shaft

122‧‧‧ one-way wheel

123‧‧‧One-way bearing

125‧‧‧ height adjustment device

126‧‧‧ limit device

128‧‧‧screw post

129‧‧‧Screw Cap

130‧‧‧ Height Adjustment Department

2‧‧‧ cam

20‧‧‧ Push Components

21‧‧‧ recess

22‧‧‧ convex

3‧‧‧ elastic

4‧‧‧ Slider

41‧‧‧first rack

410‧‧‧First traction unit

42‧‧‧ Wheel

510‧‧‧ Push Department

52‧‧‧Second rack

6‧‧‧ Gear Set

60‧‧‧Push stroke conversion element

7‧‧‧Guide (slide)

70‧‧‧ Sliding track element

FIG. 1 is a schematic exploded perspective view of most of an automatic returning device for a crankshaft with a deceleration function according to an embodiment of the present invention; FIG.

2a is a schematic plan view of a large part of an automatic returning device for a crankshaft with a deceleration function according to an embodiment of the present invention;

2b is a schematic plan view of a large part of an automatic returning device for a crankshaft with a deceleration function according to an embodiment of the present invention;

3 is a schematic longitudinal sectional view of a large part of an automatic returning device for a crankshaft with a deceleration function according to an embodiment of the present invention;

4 is a schematic longitudinal sectional view of a large part of an automatic returning device for a crankshaft with a deceleration function according to another embodiment of the present invention;

5 is a schematic cross-sectional view of a large part of an automatic returning device for a crankshaft with a deceleration function according to another embodiment of the present invention;

FIG. 6 is a schematic structural diagram of a damping device of an automatic returning device for a crankshaft having a function of decelerating or controlling speed in another embodiment of the present invention; FIG.

7 is a schematic cross-sectional view of the damping device shown in FIG. 6 according to the present invention;

8 is a schematic diagram of a damping device of a crankshaft automatic homing device with a deceleration function according to an embodiment of the present invention;

9 is a schematic diagram of a damping device of a crankshaft automatic homing device with a deceleration function in another embodiment of the present invention;

FIG. 10 is a schematic diagram of a damping device installation position of an automatic returning device of a crankshaft with a speed reduction or speed control function according to an embodiment of the present invention; FIG.

11 is a schematic cross-sectional view of a structure of a height adjustment device of a crankshaft automatic homing device having a speed control function according to an embodiment of the present invention;

12 is a schematic structural cross-sectional view of a height adjustment device and a limit device of an automatic returning device of a crankshaft having a speed control function according to an embodiment of the present invention;

13 is a schematic cross-sectional view of a structure of a height adjustment device of an automatic returning device of a crankshaft having a speed control function according to an embodiment of the present invention;

14 is an exploded schematic view of a height adjustment device and a limit device of an automatic returning device of a crankshaft having a speed control function according to an embodiment of the present invention;

15 is a schematic cross-sectional view of a structure of a height adjustment device of an automatic returning device for a crankshaft having a speed control function according to an embodiment of the present invention;

16 is a schematic sectional view of a groove position for eliminating or reducing the resistance of a damping device of an automatic returning device of a crankshaft having a function of deceleration or speed control according to an embodiment of the present invention;

FIG. 17 is a schematic diagram of the principle of emergency braking in an automatic homing device of a crankshaft with a function of deceleration or speed control according to an embodiment of the present invention; FIG.

18 is a schematic diagram of an emergency braking angle in an automatic returning device of a crankshaft having a function of deceleration or speed control according to an embodiment of the present invention;

FIG. 19 is a graph of a thrust force provided by a pushing portion and a friction force curve provided by a damping device in a crankshaft automatic homing device having a deceleration function according to an embodiment of the present invention; FIG.

FIG. 20 is a curve diagram of the thrust force provided by the pushing portion of the pushing portion and the friction force provided by the damping device in a crankshaft automatic homing device with a speed control function according to an embodiment of the present invention.

Claims (10)

An automatic homing device for a crankshaft with a speed reduction or speed control function, which comprises a base, and the base is provided with: a crankshaft, a pushing element fixed on the crankshaft, and the pushing element has a pushing track A slider that accepts the pushing trajectory of the pushing element and has a tendency to slide from a first position toward a second position along a displacement path; a reset device that provides the slider to return from the second position to the first position The function of one position; at least a first traction part provided on the sliding member; a pushing part and at least one pushing stroke conversion element connected between the first traction part and the pushing part so that the pushing part is opposite to The displacement of the first traction portion is enlarged; a damping device is provided on the pushing portion, and the damping device is configured to provide resistance when the slider is restored from the second position to the first position. The automatic homing device for a crankshaft according to item 1 of the scope of patent application, wherein the damping device includes a rotating shaft provided on the pushing device, and the rotating shaft is provided with a unidirectional wheel; the unidirectional wheel The direction of the rotation path is the same as the direction in which the second position slides toward the first position. The automatic homing device for a crankshaft according to item 2 of the scope of patent application, wherein the unidirectional wheel further includes a unidirectional bearing, and the unidirectional bearing is sleeved on the rotating shaft. The automatic homing device for a crankshaft according to item 1 of the scope of the patent application, wherein the damping device generates resistance by friction with at least one inner side surface of the base or the bottom surface of the top cover. The automatic homing device for a crankshaft according to item 4 of the scope of patent application, characterized in that at least one set of height adjustment devices is also provided on the inner surface or the bottom surface of the top cover which is in friction with the damping device, and the height adjustment device Adjust the friction between the damping device and the inner surface to achieve speed control. The automatic homing device for a crankshaft according to item 5 of the scope of patent application, wherein the height adjustment device further includes a screw post fixed on the top cover and a screw cap matching the screw post, and further includes a height An adjusting part, and the screw cap is fixed on the height adjusting part. The automatic homing device for a crankshaft according to item 5 of the scope of patent application, wherein the height adjustment device further includes a limit device that controls the height of the height adjustment device, and the limit device reserves a predetermined height. Space for height adjustment device to change height. The automatic homing device for a machine shaft according to item 5 of the scope of the patent application, wherein the height adjusting device is a plurality of groups, and the plurality of groups of height adjusting devices can control the homing speed of the machine shaft at different angles. The automatic homing device for a crankshaft according to item 1 of the scope of the patent application, wherein a groove for eliminating or reducing resistance is provided on a path of the damping device. The automatic homing device for a crankshaft according to any one of claims 1-9, wherein the resistance provided by the damping device when the slider is restored from the second position to the first position is reset on the crankshaft. When it reaches 45 °, it is equivalent to the thrust of the pushing part to realize emergency braking.