Transmission mechanism and electric push rod

Abstract

The transmission mechanism comprises a shell, a power shaft, a base, an electromagnet and a brake pad, the power shaft is rotatably arranged in the shell, the base is fixedly arranged in the shell, the electromagnet is installed in the base, the brake pad is arranged in the shell, and the brake pad rotates along with the power shaft in the rotating direction. The brake pad is in floating connection with the power shaft in the axial direction, in the normal working state, the brake pad and the base are spaced, in the braking state, the brake pad floats under the magnetic force effect of the electromagnet and is attached to the base, and the friction resistance between the brake pad and the base limits rotation of the brake pad. Therefore, the power shaft fixedly connected with the brake pad in the rotating direction is braked through the brake pad, noise generated by friction is avoided, meanwhile, structural stability of the brake pad is facilitated, and the braking effect on the power shaft is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of telescopic devices, in particular to a transmission mechanism and an electric push rod. Background Art

[0002] Traditional electric push rods generally adopt the method of torsion spring braking. When the motor shaft rotates forward, the acting force between the torsion spring and the motor shaft is small and does not affect the operation of the motor. When the electric push rod needs to retract, the motor shaft rotates reversely, driving the two free ends of the torsion spring to tighten, so as to achieve the braking effect.

[0003] However, when such electric push rods with braking functions are working normally, there is still a certain amount of friction between the torsion spring and the motor shaft, which is easy to generate noise, and the braking force of the torsion spring is not very stable, resulting in a poor braking effect. Summary of the Utility Model

[0004] In view of this, the utility model provides a transmission mechanism and an electric push rod, which are used to solve the problems that when the existing electric push rod with braking function is working normally, there is still a certain amount of friction between the torsion spring and the motor shaft, which is easy to generate noise, and the braking force of the torsion spring is not very stable, resulting in a poor braking effect.

[0005] To achieve one or part or all of the above purposes or other purposes, the utility model provides a transmission mechanism, which includes a housing, a power shaft, a base, an electromagnet and a brake pad. The power shaft is rotatably arranged in the housing, the base is fixedly arranged in the housing, the electromagnet is installed in the base, the brake pad is arranged in the housing, and the brake pad rotates with the power shaft in the rotation direction and is floatingly connected with the power shaft in the axial direction. In the normal working state, the brake pad is spaced from the base, and in the braking state, the brake pad floats under the magnetic force of the electromagnet and fits with the base.

[0006] Preferably, both the brake pad and the base are coaxially sleeved on the power shaft, and the power shaft is rotatably connected with the base.

[0007] Preferably, the electromagnet is an electromagnetic coil, and the electromagnetic coil is coaxially embedded in the base.

[0008] Preferably, a fixing piece is also fixedly sleeved on the power shaft, the fixing piece is located on the side of the brake pad away from the base, and an elastic member is arranged between the fixing piece and the brake pad.

[0009] Preferably, the elastic member is a spring piece, one side of the spring piece is fixedly connected with the fixing piece, and the other side of the spring piece is fixedly connected with the brake pad.

[0010] Preferably, a worm gear is also fixedly sleeved on the power shaft, and the worm gear is located on the side of the base away from the brake pad.

[0011] Preferably, a transfer shaft is provided at one end of the worm gear close to the base, and a transfer cavity rotatably connected to the transfer shaft is provided on one side of the base.

[0012] Preferably, a linkage shaft is also fixedly sleeved on the power shaft. A linkage cavity is provided at one end of the worm gear away from the base. One end of the linkage shaft is clamped in the linkage cavity, and the other end of the linkage shaft is rotatably connected to the inner wall of the housing. The linkage shaft rotates with the worm gear in the rotational direction.

[0013] Preferably, the transfer shaft and the inner wall of the transfer cavity, and the linkage shaft and the inner wall of the housing are all rotatably connected through bearings.

[0014] An electric push rod includes a transmission mechanism, a motor, a lead screw, and a nut. The motor is arranged on one side of the housing. A worm is provided at the output end of the motor. The worm penetrates into the housing and meshes with a worm gear. The lead screw is located on one side of the housing, and one end of the lead screw is fixedly connected to a power shaft. The nut is threadedly connected to the lead screw.

[0015] Implementing the embodiments of the present invention will have the following beneficial effects:

[0016] After adopting the above-mentioned transmission mechanism and electric push rod, during use, the power shaft can be driven by a power device. In the normal working state, the brake pad is spaced from the base. In the braking state, the brake pad floats under the magnetic force of the electromagnet and fits with the base. The frictional resistance between the brake pad and the base will limit the rotation of the brake pad, thereby stopping the power shaft fixedly connected thereto in the rotational direction through the brake pad. And when the brake pad rotates with the power shaft, the circumferential side of the brake pad will not contact the inner wall of the housing, which not only avoids noise generated by friction, but also is beneficial to the structural stability of the brake pad to ensure that the brake pad provides reliable braking force and improves the braking effect on the power shaft. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0018] Among them:

[0019] Figure 1 is a three-dimensional view of the present invention;

[0020] Figure 2 is an explosion Figure 1 ;

[0021] Figure 3 is the explosion of the present utility model Figure 2 .

[0022] In the figure: 1. housing; 11. power shaft; 2. base; 21. transfer cavity; 3. electromagnet; 41. brake pad; 42. spring plate; 421. first connection point; 422. second connection point; 43. fixing plate; 431. screw hole; 5. worm gear; 51. transfer shaft; 52. linkage cavity; 53. block; 54. bearing; 6. linkage shaft; 61. card slot; 7. motor; 71. worm; 8. lead screw; 9. nut. Specific embodiments

[0023] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the technical field to which this utility model belongs; the terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this utility model; the terms "including" and "having" and any variations thereof in the specification and claims of this utility model and the above drawings are intended to cover non-exclusive inclusion. The terms "first", "second", etc. in the specification and claims of this utility model or the above drawings are used to distinguish different objects and not to describe a specific order.

[0024] Reference to "embodiment" herein means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of this utility model. The phrase appears in various places in the specification and does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0025] In order to enable those skilled in the art of this technology to better understand the solution of this utility model, the technical solutions in the embodiments of this utility model will be clearly and completely described below with reference to the drawings.

[0026] Such as Figures 1-3As shown in the figure, a transmission mechanism includes a housing 1, a power shaft 11, a base 2, an electromagnet 3 and a brake pad 41. The power shaft 11 is rotatably arranged in the housing 1. The base 2 is fixedly arranged in the housing 1. The electromagnet 3 is installed in the base 2. The brake pad 41 is arranged in the housing 1, and the brake pad 41 rotates with the power shaft 11 in the rotational direction and is floatingly connected to the power shaft 11 in the axial direction. During use, the power shaft 11 can be driven by a power device. In the normal working state, the brake pad 41 is spaced from the base 2. In the braking state, the brake pad 41 floats under the magnetic force of the electromagnet 3 and fits with the base 2. The frictional resistance between the brake pad 41 and the base 2 will limit the rotation of the brake pad 41, so as to stop the power shaft 11 fixedly connected to it in the rotational direction through the brake pad 41. And when the brake pad 41 rotates with the power shaft 11, the circumferential side of the brake pad 41 will not contact the inner wall of the housing 1, which not only avoids noise generated by friction, but also is beneficial to the structural stability of the brake pad 41 to ensure that the brake pad 41 provides reliable braking force and improves the braking effect on the power shaft 11.

[0027] Further, both the brake pad 41 and the base 2 are coaxially sleeved on the power shaft 11, and the power shaft 11 is rotatably connected to the base 2.

[0028] Further, the electromagnet 3 is an electromagnetic coil, and the electromagnetic coil is coaxially embedded in the base 2.

[0029] Further, a fixing piece 43 is also fixedly sleeved on the power shaft 11. The fixing piece 43 is located on the side of the brake pad 41 away from the base 2. An elastic member is arranged between the fixing piece 43 and the brake pad 41. A plurality of screw holes 431 are provided along the radial direction of the circumferential side of the fixing piece 43, and fastening screws (not shown in the attached drawing) are threadedly connected in the screw holes 431. During use, the fixing piece 43 is fixed on the power shaft 11 by tightening the fastening screws.

[0030] Further, the elastic member is a spring piece 42. One side of the spring piece 42 is fixedly connected to the fixing piece 43, and the other side of the spring piece 42 is fixedly connected to the brake pad 41.

[0031] Specifically, a plurality of first connection points 421 and a plurality of second connection points 422 are alternately and evenly arranged along the circumferential direction on the spring piece 42. The plurality of first connection points 421 are fixedly connected to the fixing piece 43, and the plurality of second connection points 422 are fixedly connected to the brake pad 41. The fixed connection method can be welding or riveting. In this embodiment, riveting is preferably used so that the fixing piece 43 and the brake pad 41 are fixed in the rotational direction through the spring piece 42.

[0032] In this embodiment, when the electromagnetic coil is energized to generate a magnetic field to attract the brake pad 41, the area where the second connection point 422 of the spring piece 42 is located can be adaptively deformed, so that the brake pad 41 floats axially along the power shaft 11 and fits with the end of the base 2, thereby braking the power shaft 11. When the electromagnetic coil is de-energized and the electromagnetic attraction disappears, the spring piece 42 will release energy and reset, driving the brake pad 41 to reset and disengage from the end of the base 2 through the second connection point 422, releasing the restriction on the power shaft 11.

[0033] In one embodiment, the elastic member can be a spring. The brake pad 41 is slidably connected to the power shaft 11. When the brake pad 41 adsorbs to the end of the base 2, the spring deforms and stretches. When the magnetic attraction disappears, the spring releases energy and retracts, pulling the brake pad 41 away from the end of the base 2 (not shown in the drawings).

[0034] Further, a worm gear 5 is fixedly sleeved on the power shaft 11. The worm gear 5 is located on the side of the base 2 away from the brake pad 41.

[0035] Further, a transfer shaft 51 is provided at one end of the worm gear 5 close to the base 2. A transfer cavity 21 for rotatably connecting with the transfer shaft 51 is provided on one side of the base 2, so as to rotatably connect the worm gear 5 to the fixed base 2 and improve the installation stability of the worm gear 5.

[0036] Further, a linkage shaft 6 is fixedly sleeved on the power shaft 11. A linkage cavity 52 is provided at one end of the worm gear 5 away from the base 2. One end of the linkage shaft 6 is clamped in the linkage cavity 52, and the other end of the linkage shaft 6 is rotatably connected to the inner wall of the housing 1. The linkage shaft 6 rotates in the same direction as the worm gear 5. When the worm gear 5 is driven by a suitable power device, the worm gear 5 will drive the linkage shaft 6 clamped thereto to rotate synchronously, thereby driving the power shaft 11 fixedly connected to the linkage shaft 6 to rotate through the linkage shaft 6 to achieve the transmission purpose.

[0037] Specifically, a plurality of card slots 61 are circumferentially distributed on the side wall of one end of the linkage shaft 6. The card slots 61 are all arranged along the axial direction of the linkage shaft 6. A plurality of blocks 53 are circumferentially distributed on the inner wall of the linkage cavity 52. The blocks 53 are respectively clamped with the card slots 61, so that the worm gear 5 and the linkage shaft 6 are fixed in the rotation direction.

[0038] Further, the transfer shaft 51 and the inner wall of the transfer cavity 21, and the linkage shaft 6 and the inner wall of the housing 1 are all rotatably connected through bearings 54 to reduce the rotation resistance of the worm gear 5 and the linkage shaft 6 and make the rotation of the power shaft 11 smoother.

[0039] An electric push rod includes a transmission mechanism, as well as a motor 7, a lead screw 8 and a nut 9. The motor 7 is arranged on one side of the housing 1. A worm 71 is provided at the output end of the motor 7. The worm 71 penetrates into the housing 1 and meshes with a worm wheel 5. The lead screw 8 is located on one side of the housing 1, and one end of it is fixedly connected coaxially with a power shaft 11. The nut 9 is threadedly connected to the lead screw 8. The motor 7 can drive the power shaft 11 to rotate through the transmission of the worm 71 and the worm wheel, thereby driving the lead screw 8 to rotate. By using the thread of the lead screw 8, the nut 9 is driven to translate along its axial direction, and the movable member fixedly connected to the nut 9 is pushed to move. In this embodiment, the lead screw 8 and the power shaft 11 are integrally formed.

[0040] Obviously, the above-described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. The accompanying drawings show the preferred embodiments of the present invention, but do not limit the patent scope of the present invention. The present invention can be implemented in many different forms. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosed content of the present invention more thorough and comprehensive. Although the present invention has been described in detail with reference to the foregoing embodiments, for those skilled in the art, they can still modify the technical solutions described in the foregoing specific embodiments, or perform equivalent replacements on some of the technical features. Any equivalent structure made by using the specification and drawings of the present invention, directly or indirectly applied in other related technical fields, is equally within the scope of the patent protection of the present invention.

Claims

1. A transmission mechanism, characterized in that: include: housing, power shaft, base, electromagnet and brake pads; The power shaft is rotatably disposed in the housing; The base is fixedly arranged in the shell; The electromagnet is installed in the base; The brake pad is arranged in the housing, and the brake pad rotates with the power shaft in the rotation direction, and is floatingly connected with the power shaft in the axial direction; In a normal working state, the brake pad is spaced apart from the base, and in a braking state, the brake pad floats under the magnetic force of the electromagnet and fits with the base.

2. A transmission mechanism according to claim 1, characterized in that: The brake pad and the base are both coaxially sleeved on the power shaft, and the power shaft is rotatably connected to the base.

3. A transmission mechanism according to claim 2, characterized in that: The electromagnet is an electromagnetic coil, and the electromagnetic coil is coaxially embedded in the base.

4. A transmission mechanism according to claim 2, characterized in that: A fixing plate is also fixedly sleeved on the power shaft. The fixing plate is located on a side of the brake pad away from the base. An elastic member is provided between the fixing plate and the brake pad.

5. A transmission mechanism according to claim 4, characterized in that: The elastic member is a spring sheet, one side of the spring sheet is fixedly connected to the fixing sheet, and the other side of the spring sheet is fixedly connected to the brake pad.

6. A transmission mechanism according to claim 1, characterized in that: A worm gear is also fixedly sleeved on the power shaft, and the worm gear is located on a side of the base away from the brake pad.

7. A transmission mechanism according to claim 6, characterized in that: A transfer shaft is provided at one end of the worm wheel close to the base, and a transfer cavity rotatably connected to the transfer shaft is provided at one side of the base.

8. A transmission mechanism according to claim 7, characterized in that: A linkage shaft is fixedly sleeved on the power shaft, a linkage cavity is provided on the end of the worm gear away from the base, one end of the linkage shaft is clamped in the linkage cavity, the other end of the linkage shaft is rotatably connected to the inner wall of the shell, and the linkage shaft rotates with the worm gear in the rotation direction.

9. A transmission mechanism according to claim 8, characterized in that: The transfer shaft and the inner wall of the transfer cavity, and the linkage shaft and the inner wall of the shell are all rotatably connected through bearings.

10. An electric push rod, characterized in that: The transmission mechanism comprises a motor, a lead screw and a nut as described in any one of claims 6 to 9; The motor is arranged on one side of the housing, and a worm is arranged at the output end of the motor. The worm penetrates into the housing and meshes with the worm wheel. The lead screw is located on one side of the housing, and one end of the lead screw is fixedly connected to the power shaft. The nut is threadedly connected to the lead screw.

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