Linear actuator having a cushioning mechanism

Abstract

To provide a linear actuator including a cushioning mechanism.SOLUTION: A linear actuator comprises an actuator body, a quick release mechanism, and a cushioning structure. The actuator body comprises an electric motor, a feed screw, an outer tube, and a telescopic tube. The feed screw is driven by the electric motor to rotate, the outer tube is sleeved with the telescopic tube, and the telescopic tube is provided with a nut to be in threaded connection transmission with the feed screw. The quick release mechanism is installed on the feed screw and is used to release the driving of the electric motor and the feed screw. The cushioning structure is arranged on the actuator body and comprises an elastic body and a speed reduction structure. When the quick release mechanism is released, the feed screw rotates under a load of the telescopic tube and the elastic body is compressed through the nut. Further, the speed reduction structure is driven to generate a break and thereby decelerate the rotating feed screw.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to the technical field of linear actuators, and more particularly to a linear actuator provided with a cushioning mechanism.

Background Art

[0002] A linear actuator is widely known for being attached to an electric medical bed, a running machine, a wheelchair, etc., and for adjusting and converting the elevation angle and the height of the position.

[0003] In a conventional patent document, for example, Patent Document 1 below discloses a medical bed having a support frame that can be hinged and having a backrest portion where the support frame moves between a horizontal position and an inclined position of the bed frame. The bed frame supports a reversible electric drive motor and drives a screw shaft rotatably by means of a speed reduction gear device and a foldable coupling mechanism. The nut is joined to the shaft and held so as not to rotate following the shaft, and the linkage connects the nut to the backrest portion and performs a reciprocating motion along the shaft in response to the nut, thereby realizing the reciprocating motion of the backrest portion. The backrest portion is provided with a manual release device, and by disengaging the joint with a connection mechanism that can be released when activated, the screw shaft can rotate freely independently of the electric motor and the gear device.

[0004] Also, for example, Patent Document 2 below discloses a linear actuator having a reversible electric motor that drives a screw shaft joined to a roller nut. A tubular outer case connected to the nut has a base member and a load fixing lug at the distal end. A hydraulic shock absorber that provides linear deceleration is normally held in the most relaxed state and is positioned between the base member and the end of a spacer tube that abuts the nut. When the nut is positioned within the stroke distance of the shock absorber at the driven end of the shaft, the free end of the shaft presses the shock absorber against the base. When the nut is within the stroke distance of the shock absorber at the free end of the shaft, the ring and the stopper ring engage with each other, so that a fixed distance is maintained between the shock absorber body and the free end of the shaft, and the spacer tube compresses the shock absorber. A centrifugal brake is installed on the pulley of the drive shaft joint, and the rotation of the shaft is restricted so as not to exceed a predetermined speed.

[0005] Also, for example, Patent Document 3 below discloses a linear actuator equipped with a reversible electric motor that drives a non-automatically locked spindle by a drive device and axially moves a tubular positioning element, one end of which is connected to a mandrel nut of a mandrel. The actuator includes a drive device that moves the tubular positioning element from the electric motor and, partially, from the electric motor to a quick release device, and installs the spindle as a load rotation passing through the tubular positioning element. The actuator further includes a braking device that is used to control the speed of the tubular positioning element during an external load period when the quick release device is activated. The braking device is composed of a centrifugal brake, and when the quick release device is activated, it controls its own speed reduction.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Patent Document 2

Patent Document 3

[0007] Therefore, the inventor considered that the above drawbacks could be improved, and as a result of intensive studies, the inventor arrived at a proposal for the present invention that effectively improves the above problems through a rational design.

[0008] The present invention has been made in view of such conventional problems. To solve the above problems, an object of the present invention is to provide a linear actuator including a cushion mechanism that reduces the rotational feed screw by a speed reduction structure and reduces the impact force when the telescopic tube retracts inside the outer tube. MEANS FOR SOLVING THE PROBLEMS

[0009] To achieve the above object, the present invention employs the following means. A linear actuator including a cushion mechanism according to an aspect of the present invention includes an actuator body, a quick release mechanism, and a cushion structure. The actuator body includes an electric motor, a feed screw, an outer tube, and a telescopic tube. The feed screw is driven to rotate by the electric motor, the outer tube is provided to cover the outside of the telescopic tube, and the telescopic tube has a nut for screwing to be driven by the feed screw. The quick release mechanism is installed on the feed screw and is used to release the driving of the electric motor and the feed screw. The cushion structure is arranged on the actuator body and includes an elastic body and a speed reduction structure. When the quick release mechanism is released, the feed screw rotates under the load of the telescopic tube, and the nut compresses the elastic body and drives the speed reduction structure to brake, so that the speed reduction structure can reduce the speed of the rotating feed screw.

[0010] To achieve the above object, a linear actuator having a cushion mechanism according to another aspect of the present invention includes an actuator body, a quick release mechanism, and a cushion structure. The actuator body includes an electric motor, a feed screw, and a telescopic tube. The feed screw is driven to rotate by the electric motor, and the telescopic tube has a nut for screwing to be driven by the feed screw. The quick release mechanism is installed on the feed screw and is used to release the drive of the electric motor and the feed screw. The cushion structure is disposed on the actuator body and includes an elastic body and a deceleration structure. The deceleration structure includes a rotating wheel driven by the feed screw and a stopper disposed corresponding to the rotating wheel. When the nut compresses the elastic body, the elastic body deforms to activate the mechanical connection between the rotating wheel and the stopper, and the stopper brakes the rotating wheel to decelerate the feed screw.

[0011] Also, to achieve the above object, a linear actuator having a cushion mechanism according to still another aspect of the present invention includes an actuator body and a cushion structure. The actuator body includes an electric motor, a feed screw, and a telescopic tube. The feed screw is driven to rotate by the electric motor, and the telescopic tube has a nut for screwing to be driven by the feed screw. The cushion structure is disposed on the actuator body and includes an elastic body and a deceleration structure. The deceleration structure includes a rotating wheel driven by the feed screw and a stopper disposed corresponding to the rotating wheel. When the nut compresses the elastic body, the elastic body deforms to activate the mechanical connection between the rotating wheel and the stopper, and the stopper brakes the rotating wheel to decelerate the feed screw.

Advantages of the Invention

[0012] Since the present invention is configured as described above, it exhibits the effects described below. In the present invention, the installation of the reset member supports the disengagement of the engagement between the rotating wheel and the rotation stopper member. The installation of the cap enables the impact acting force of the nut to be uniformly transmitted to the elastic body. The installation of the front positioning collar and the rear positioning collar forms a stable holding effect on the elastic body. The provision of the first uneven surface and the second uneven surface of the rotating wheel and the rotation stopper member enhances the stability of the engagement between the two. The combination of the fitting block of the rotating wheel and the U-shaped opening of the guide member simplifies the attachment process and facilitates assembly. The installation of the thrust bearing prevents the occurrence of scratches and abnormal noises due to relative friction between the end face of the elastic body and the rotating wheel. The parallel arrangement of the offset wheel and the rotation stopper member shortens the ineffective stroke of the telescopic tube.

[0013] Other objects, configurations, and effects of the present invention will become apparent from the following sections on the embodiments of the invention.

Brief Description of the Drawings

[0014]

Figure 1

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Figure 21

Modes for Carrying Out the Invention

[0015] Hereinafter, embodiments of a linear actuator equipped with a cushion mechanism of the present invention will be described with reference to the drawings. However, the present invention is not limited to these embodiments, and members, materials, etc. described below can be variously modified within the scope of the gist of the present invention.

[0016] First, with reference to FIGS. 1 to 5, a linear actuator equipped with a cushion mechanism according to the present invention will be described. This linear actuator is mainly applied to a nursing bed or a medical bed (not shown), and by operating the linear actuator, an operation of raising or flattening the front stage of the nursing bed or the medical bed is executed. In particular, in the first aid process of a patient, in order to perform operations such as giving an electric shock while lying on the back, by installing this linear actuator, the impact force when the front stage of the nursing bed or the medical bed descends at high speed is reduced, the injury to the patient is reduced, and the comfort for the user to use is improved.

[0017] The above-described linear actuator mainly includes an actuator body 10, a quick release mechanism 30, and a cushion structure 50. Each will be described below.

[0018] As shown in FIG. 1, the actuator body 10 mainly includes a housing body 11, an electric motor 13, and a drive mechanism 15. The housing body 11 mainly includes a lower housing 111 and an upper housing 115, and both the upper housing 115 and the lower housing 111 are made of a material such as plastic. The lower housing 111 is composed of a round tube portion 112 and a half housing cover 113 formed by extending from one end of the round tube portion 112, and one end of the round tube portion 112 away from the half housing cover 113 is in a closed state. The upper housing 115 is also a half housing cover and is fitted to correspond to the half housing cover 113 of the lower housing 111. The lower housing 111 and the upper housing 115 are joined by a screwing member such as a screw.

[0019] The electric motor 13 is mounted inside the round tube portion 112 of the lower housing 11 and has a worm 131. This electric motor 13 is configured such that the worm 131 can rotate in the forward and reverse directions by the combination and operation of related elements such as internal magnetic poles, coils, and currents.

[0020] Referring to FIGS. 2, 4, and 5 together, the drive mechanism 15 mainly includes a feed screw 151, an outer tube 152, and a telescopic tube 153. The feed screw 151 is covered by a front bearing 154 and a rear bearing 155, the rear stage of the feed screw 151 is supported inside the lower housing 111 (see FIGS. 4 and 5), and the remaining portion of the feed screw 151 extends outside the housing body 11. A worm gear 156 corresponding to and meshing with the aforementioned worm 131 is covered on the feed screw 151 on the rear side of the front bearing 154. The feed screw 151 according to this embodiment is a non-self-locking type feed screw, that is, when the telescopic tube 153 is restrained or restricted from rotating, the telescopic tube 153 receives an axial propulsive force or pressure action, the feed screw 151 rotates freely with respect to the telescopic tube 153, and the telescopic tube 153 linearly displaces and retracts inside the outer tube 152.

[0021] The outer tube 152 is a hollow body, which is covered along the outer peripheral edge of the feed screw 151 and provides a function for supporting the telescopic tube 153. One end of the outer tube 152 is covered and fixed by the lower housing 111 and the upper housing 115.

[0022] The telescopic tube 153 is covered along the outer peripheral edge of the feed screw 151 and is formed inside the outer tube 152. A nut 157 is connected to one end of the telescopic tube 153, and the nut 157 is screwed to the above-mentioned feed screw 151 so as to drive each other. By providing a groove and a stopper (not shown) on the outer peripheral edge of the nut 157 that are fitted to the outer tube 152, the nut 157 and the telescopic tube 153 can only perform linear movement inside the outer tube 152 and cannot perform rotational movement.

[0023] As shown in FIGS. 4 and 5, the quick release mechanism 30 mainly includes a positioning wheel 31, a clutch wheel 33, and a guide member 35. The positioning wheel 31, the clutch wheel 33, and the guide member 35 are all cylindrical bodies. The positioning wheel 31 is mounted on and fixed to the feed screw 151, and the positioning wheel 31 can rotate following the feed screw 151. The clutch wheel 33 is mounted on the feed screw 151 by the guide member 35 and is formed on the side of the positioning wheel 31. The clutch wheel 33 moves axially thereon under the guiding action of the guide member 35. A plurality of recesses are provided on one side of the clutch wheel 33 (not shown), and a plurality of protrusions are provided on the outer peripheral edge of the positioning wheel 31 (not shown). Similarly, each of the protrusions and each of the recesses are installed so as to be compatible between the positioning wheel and the clutch wheel. Each of the protrusions fits into each of the recesses, and the clutch wheel 33 can be operably engaged or disengaged with the positioning wheel 31.

[0024] Referring to FIG. 1 again, the quick release mechanism 30 according to this embodiment is pivotally attached to the outside of the upper housing 115 (see FIG. 1), and further includes a pull lever 37 connected to the clutch wheel 33 described above via a connecting member (not shown) installed inside the upper housing 115. Therefore, by operating the pull lever 37, the clutch wheel 33 slides on the guide member 35 and engages or disengages corresponding to the positioning wheel 31.

[0025] The feed screw 151 is driven by being engaged by the worm 131 and the worm gear 156 of the electric motor 13. When the clutch wheel 33 and the positioning wheel 31 are engaged, the feed screw 151 is driven to rotate together with the positioning wheel 31, the clutch wheel 33, and the guide member 35. When the clutch wheel 33 and the positioning wheel 31 are disengaged, the feed screw 151 receives the load of the telescopic tube 153 and rotates freely together with the positioning wheel 31. At this time, the clutch wheel 33, the guide member 35, and the worm gear 156 are restricted from rotating by the worm 131.

[0026] Referring also to FIG. 3, the cushion structure 50 is installed on the feed screw 151. The cushion structure 50 according to the present embodiment is located between the nut 157 and the worm gear 156, and the cushion structure 50 mainly includes an elastic body 51 and a deceleration structure 53. The elastic body 51 according to the present embodiment is a compression spring, and the deceleration structure 53 according to the present embodiment mainly includes a rotating wheel 531, a rotation stopper member 533, and an actuator element 535. The rotation stopper member 533 and the actuator element 535 jointly constitute the stopper according to the present embodiment. The shapes of the rotating wheel 531 and the rotation stopper member 533 according to the present embodiment are cylindrical, but are not limited to this shape. The rotating wheel 531 is installed adjacent to the nut 157, the rotation stopper member 533 is installed on the side away from the nut 157 of the rotating wheel 531, and the actuator element 535 is mounted on the outer peripheral edge of the rotation stopper member 533. The actuator element 535 according to the present embodiment is a spring, but is not limited to this form. One end of the spring is fixed to the housing body 11 of the actuator body 10.

[0027] In one embodiment, the rotating wheel 531 is provided with a plurality of protrusions 5313 facing the end face of the rotation stopper member 533, and the rotation stopper member 533 is provided with a plurality of recesses 5331 facing the end face of the rotating wheel 531. Each of the recesses 5331 is arranged to correspond to each of the protrusions 5313 and is operably engaged or disengaged. Similarly, each of the protrusions 5313 and each of the recesses 5331 are installed between the rotation stopper member 533 and the rotating wheel 531 so as to be compatible. The number of the above-mentioned protrusions 5313 and recesses 5331 may be one.

[0028] The speed reduction structure 53 according to this embodiment further includes a guide member 537 that covers the feed screw 151 and rotates together with the feed screw 151. The rotating wheel 531 and the rotation stopper member 533 are mounted on the guide member 537. The guide member 537 mainly includes a lower case 5371 and an upper case 5373. The upper case 5373 is fitted to the lower case 5371 correspondingly and is jointly mounted on the feed screw 151. A first positioning plane 1511 is provided on the circumferential surface of the feed screw 151, and a second positioning plane 5377 is provided inside the upper case 5373 and the lower case 5371. In this way, by fitting and positioning the first positioning plane 1511 and the second positioning plane 5377 with each other, the guide member 537 rotates together following the feed screw 151.

[0029] Also, a plurality of guide protrusions 5375 extend on the circumferential surface of the guide member 537, and a plurality of guide grooves 5311 are provided on the inner wall of the rotating wheel 531. Each of the guide protrusions 5375 is fitted to each of the guide grooves 5311 correspondingly. By fitting each of the guide grooves 5311 to each of the guide protrusions 5375 of the guide member 537, the guide member 537 is driven to rotate following the rotating wheel 531. By mounting the rotation stopper member 533 in an area where the guide member 537 does not have the guide protrusion 5375, when the rotating wheel 531 is not activated by the elastic body 51, the rotation stopper member 533 and the rotating wheel 531 are not mechanically connected. At this time, the rotation stopper member 533 is restricted by the actuator element 535 so as not to rotate following the feed screw 151 and the guide member 537. After the rotating wheel 531 is pushed by the elastic body 51, the rotating wheel 531 and the rotation stopper member 533 are mechanically connected ( "mechanically connected" means that each of the aforementioned protrusions 5313 is fitted and coupled to each of the recesses 5331 correspondingly. Similarly, they may be coupled by a method such as friction), and the rotation stopper member 533 is restricted by the actuator element 535, so that the rotation stopper member 533 stops the rotation of the rotating wheel 531. The number of the aforementioned guide grooves 5311 and the portion 5375 may be one.

[0030] The speed reduction structure 53 according to this embodiment further includes a reset member 539 installed between the rotating wheel 531 and the rotation stopping member 533. When the rotating wheel 531 is not abutted by the elastic body 51, the reset member 539 pushes away the rotating wheel 531 to disengage the engagement between the rotating wheel 531 and the rotation stopping member 533. Similarly, the reset member 539 is installed inside or outside the rotating wheel 531 or the rotation stopping member 533.

[0031] The cushion structure 50 according to this embodiment further includes a cap 55 installed at one end of the elastic body 51 away from the speed reduction structure 53. When the nut 157 directly collides with the elastic body 51, the cap 55 uniformly transmits the acting force of the collision to the elastic body 51.

[0032] The cushion structure 50 according to this embodiment further includes a thrust bearing 57 installed on the outer peripheral edge of the rotating wheel 531. The rotating wheel 531 rotates following the feed screw 151. By installing the thrust bearing 57, the elastic body 51 is prevented from rotating. After the elastic body 51 is compressed and deformed by the nut 157, installing the thrust bearing 57 prevents the occurrence of problems such as relative friction between the end face of the elastic body 51 and the rotating wheel 531, resulting in scratches or abnormal noises. Similarly, the aforementioned thrust bearing 57 can be replaced by a gasket.

[0033] In one embodiment, it further includes at least one position limiting member 60 that penetrates and is fixed to the outer tube 152 and is used to limit the movement stroke of the cap 55 or / and the elastic body 51.

[0034] The linear actuator equipped with the cushion mechanism according to the present invention further includes a rear receiving seat 70 and a front receiving seat 75. The rear receiving seat 70 is covered on the rear side of the rear bearing 155 and is sandwiched and fixed by the upper housing 115 and the lower housing 111. The front receiving seat 75 is installed at the end of the telescopic tube 153 away from the nut 157.

[0035] In use, by operating the pull lever 37, the clutch wheel 33 and the positioning wheel 31 are disengaged. By using the patient's own weight or applying pressure to the front section of the nursing bed or medical bed by a medical staff member, the telescopic tube 153 receives the aforementioned load, and the nut 157 drives the feed screw 151 to rotate, causing the telescopic tube 153 to retract inside the outer tube 152. At the end position of the moving stroke of the telescopic tube 153, the nut 157 presses the cap 55 and the elastic body 51, causing the elastic body 51 to be compressed and deformed. Subsequently, the compression force generated after the elastic body 51 is deformed pushes the rotating wheel 531 in the direction of the rotation stopping member 533. At this time, each of the protruding portions 5313 of the rotating wheel 531 is fitted into each of the recesses 5331 of the rotation stopping member 533, and the rotating wheel 531 drives the rotation stopping member 533 to rotate together. The actuator element 535 restrains and limits the rotation stopping member 533, thereby stopping the rotation of the rotating wheel 531 and the feed screw 151 by the rotation stopping member 533. By doing so, the rotation speed of the feed screw 151 is reduced, and at the same time, the moving speed at which the telescopic tube 153 retracts into the outer tube 152 is also reduced.

[0036] As shown in FIGS. 6 to 8, the linear actuator provided with the cushion mechanism according to this embodiment has substantially the same structure as that of the first embodiment described above. The difference is that the speed reduction structure 53A according to this embodiment mainly includes a rotating wheel 531A, a rotation stopping member 533A, and an actuator element 535. The rotating wheel 531A is provided with a first friction surface 5314 facing the end surface of the rotation stopping member 533A, and the rotation stopping member 533A is provided with a second friction surface 5334 facing the end surface of the rotating wheel 531A. It is driven to rotate by the friction between the first friction surface 5314 and the second friction surface 5334.

[0037] As shown in FIGS. 9 and 10, regarding the differences between each of the above-described embodiments of the linear actuator including the cushion mechanism according to the present embodiment, the deceleration structure 53B according to the present embodiment mainly includes a rotating wheel 531B, a rotation stopper member 533B, and an actuator element 535. A first magnet 5315 is installed on the rotating wheel 531B, and a second magnet 5333 is installed on the rotation stopper member 533B. The first magnet 5315 and the second magnet 5333 jointly constitute a reset member according to the present embodiment. Similarly, between the rotating wheel 531B and the rotation stopper member 533B, it is driven to rotate by the frictional action of its end face. The first magnet 5315 and the second magnet 5333 utilize the action of repulsion between the same magnetic poles, and when the rotating wheel 531B is not abutted by the elastic body 51, it can be detached from the mechanical connection with the rotation stopper member 533B. In the present embodiment, the corresponding end faces of the rotating wheel 531B and the rotation stopper member 533B are driven to rotate by an uneven structure or a connection of a key and a groove.

[0038] As shown in FIG. 11, regarding the differences between each of the above-described embodiments of the linear actuator including the cushion mechanism according to the present embodiment, the deceleration structure 53C according to the present embodiment mainly includes a rotating wheel 531C and a rotation stopper member 533C, and the rotation stopper member 533C constitutes a stopper according to the present embodiment. One end of the elastic body 51 is fixed to be constrained to the outer peripheral edge of the rotation stopper member 533C. A positioning plane (not shown) that fits with the plane of the feed screw 151 is provided inside the rotating wheel 531C, and the rotating wheel 531C is driven by the feed screw 151 to rotate together. The elastic body 51 deforms to generate a compressive force to push and mechanically connect the rotation stopper member 533C and the rotating wheel 531C, and the braking action of the friction between the first friction surface 5314 of the rotating wheel 531C and the second friction surface 5334 of the rotation stopper member 533C reduces the rotation speed of the rotating feed screw 151 during rotation or stops the rotation.

[0039] As shown in FIGS. 12 to 16, regarding the differences from the first embodiment of the linear actuator including the cushion mechanism according to the present embodiment, the deceleration structure 53D according to the present embodiment mainly includes a rotating wheel 531D, a rotation stopping member 533D, and an actuator element 535. The rotating wheel 531D is provided with a first uneven surface 5317 facing the end surface of the rotation stopping member 533D, and the rotation stopping member 533D is provided with a second uneven surface 5335 facing the end surface of the rotating wheel 531D. Since the first uneven surface 5317 and the second uneven surface 5335 can be operably engaged or disengaged, the stability of the engagement between the two is enhanced.

[0040] The guide member 537D is provided with a U-shaped opening 5379 that is fitted so as to correspond to the first positioning plane 1511 of the feed screw 151, so that the guide member 537D can rotate together following the feed screw 151. A fitting block 5319 is installed inside the rotating wheel 531D and is movably connected to the aforementioned U-shaped opening 5379. When the rotating wheel 531D moves axially with respect to the guide member 537D, it can rotate following this movement. The rotation stopping member 533D is fitted to the guide member 537D and does not rotate when the rotating wheel 531D and the rotation stopping member 533D are not mechanically connected. In this way, the installation process is simplified and the assembly is facilitated.

[0041] The cushion structure 50D according to the present embodiment further includes a front positioning collar 56 and a rear positioning collar 56, and the front positioning collar 56 and the rear positioning collar are respectively fitted to both ends of the elastic body 51. By doing so, an effect of stably holding the elastic body 51 is formed.

[0042] The present embodiment further includes a plurality of position limiting members 60, and each of the position limiting members 60 is provided through and fixed to the outer tube 152. By doing so, the movement stroke of the front positioning collar 56 is restricted. The number of the position limiting members 60 may be one.

[0043] As shown in FIGS. 17 to 21, regarding the differences from the aforementioned fifth embodiment of the present embodiment, the speed reduction structure 53E according to the present embodiment mainly includes a rotating wheel 531E, a rotation stopping member 533E, an actuator element 535, and a displacement wheel 536. The rotation stopping member 533E, the actuator element 535, and the displacement wheel 536 jointly constitute the stopper according to the present embodiment. The rotating wheel 531E is similarly connected to the feed screw 151 via the guide member 537E and rotates following it. The rotation stopping member 533E is fitted on the guide member 537E. When the rotating wheel 531E and the rotation stopping member 533E are not mechanically connected, the rotation stopping member 533E does not rotate. The displacement wheel 536 is pivotally provided on the housing body 11 of the actuator body 10 and is connected to the rotation stopping member 533E. The actuator element 535 is fitted on the displacement wheel 536, and one end of the actuator element 535 is fixed within the housing body 11 of the actuator body 10. Therefore, the ineffective stroke of the expansion and contraction tube 153 can be shortened.

[0044] In one embodiment, the speed reduction structure 53E further includes a reset member 539 installed between the rotating wheel 531E and the rotation stopping member 533E. When the rotating wheel 531E is not abutted by the elastic body 51, it pushes away the rotating wheel 531E and disengages the rotating wheel 531E and the rotation stopping member 533E from the engagement.

[0045] In one embodiment, the rotating wheel 531E is provided with a locking groove 5336 facing the end face of the rotation stopping member 533E, and the rotation stopping member 533E is provided with a locking block 5316 facing the end face of the rotating wheel 531E. The locking block 5316 and the locking groove 5336 can be operably engaged or disengaged. A plurality of first convex teeth 5337 are extended on the circumferential surface of the rotation stopping member 533E, and a plurality of second convex teeth 5361 are extended on the circumferential surface of the displacement wheel 536. By engaging each of the first convex teeth 5337 and each of the second convex teeth 5361, they are driven to rotate.

[0046] The above embodiments are only for explaining the technical idea and features of the present invention, and are intended to enable those skilled in the art to understand the content of the present invention and implement it accordingly, and do not limit the scope of the claims of the present invention. Therefore, improvements or changes with various similar effects made without departing from the spirit of the present invention shall be included in the claims described below.

Description of Reference Numerals

[0047] 10 Actuator body 11 Housing body 111 Lower housing 112 Round tube portion 113 Half housing cover 115 Upper housing 13 Electric motor 131 Worm 15 Driving mechanism 151 Feed screw 1511 First positioning plane 152 Outer tube 153 Telescopic tube 154 Front bearing 155 Rear bearing 156 Worm gear 157 Nut 30 Quick release mechanism 31 Positioning wheel 33 Clutch wheel 35 Guide member 37 Pull lever 50 Cushion structure 50D Cushion structure 50E Cushion structure 51 Elastic body 53 Reduction structure 53A Reduction structure 53B Reduction structure 53C Reduction structure 53D Reduction structure 53E Reduction structure 531 Rotating wheel 531A Rotating wheel 531B Rotating wheel 531C Rotating wheel 531D Rotating wheel 531E Rotating wheel 5311 Guide groove 5313 Protrusion 5314 First friction surface 5315 First magnet 5316 Locking block 5317 First uneven surface 5319 Fitting block 533 Rotation stop member 533A Rotation stop member 533B Rotation stop member 533C Rotation stop member 533D Rotation stop member 533E Rotation stop member 5331 Recess 5333 Second magnet 5334 Second friction surface 5335 Second uneven surface 5336 Locking groove 5337 First convex tooth 535 Actuator element 536 Offset wheel 5361 Second convex tooth 537 Guide member 537D Guide member 537E Guide member 5371 Lower case 5373 Upper case 5375 Guide protrusion 5377 Second positioning plane 5379 U-shaped opening 539 Reset member 55 Cap 56 Front positioning collar 57 Thrust bearing 58 Rear positioning collar 60 Position limiting member 70 Rear receiving seat 75 Front receiving seat

Claims

1. an actuator body including an electric motor, a feed screw, an outer tube, and a telescopic tube, the feed screw being driven to rotate by the electric motor, the outer tube being disposed outside the telescopic tube, and the telescopic tube having a nut for screwingly engaging the feed screw to drive the feed screw; a quick release mechanism provided on the feed screw for releasing the drive of the electric motor and the feed screw; a cushion mechanism disposed in the actuator body and including an elastic body and a deceleration structure; the deceleration structure includes a rotating wheel and a rotation stopper member arranged to correspond to the rotating wheel, the rotating wheel is mounted on the feed screw and rotates following the feed screw, and the rotation stopper member is mounted on the feed screw and mechanically connected to the rotating wheel to brake the rotating wheel; A linear actuator characterized in that, when the quick release mechanism is released, the feed screw rotates under the load of the telescopic tube, and the nut drives the reduction mechanism so as to compress and brake the elastic body, thereby enabling the reduction mechanism to decelerate the feed screw during rotation.

2. 2. The linear actuator according to claim 1, wherein the deceleration structure further comprises an actuator element installed on the rotation stop member, and the rotation stop member is restricted by the actuator element so as not to rotate in conjunction with the feed screw.

3. 3. The linear actuator according to claim 2, wherein the actuator element is a spring, one end of the spring being fixed to the actuator body.

4. The linear actuator according to claim 1, characterized in that the rotating wheel is provided with at least one protrusion, and the rotation stop member is provided with at least one recess that engages with or disengages from the protrusion.

5. The linear actuator of claim 1, characterized in that the reduction mechanism further comprises a guide member, the rotating wheel is connected to the feed screw via the guide member, the guide member is provided with at least one guide protrusion, the rotating wheel is provided with at least one guide groove that can be fitted to correspond to the guide protrusion, and the rotation stop member is installed on the guide member.

6. The linear actuator of claim 5, characterized in that the guide member comprises a lower case and an upper case, the upper case being fitted to correspond to the lower case and fitted over the feed screw, the feed screw being provided with a first positioning plane, and the upper case and the lower case each being provided with a second positioning plane that can be fitted to position on the first positioning plane.

7. 2. The linear actuator according to claim 1, wherein the deceleration structure further comprises a reset member installed on any one of the rotating wheel, the rotation stop member, and the rotating wheel, and the rotation stop member.

8. 8. The linear actuator according to claim 7, wherein the reset member is a spring or a magnet.

9. 2. The linear actuator according to claim 1, wherein the cushion mechanism further comprises a thrust bearing mounted on the rotating wheel.

10. 2. The linear actuator of claim 1, wherein the rotating wheel is provided with a first friction surface, and the rotation stop member is provided with a second friction surface that is driven to rotate by the first friction surface.

11. The linear actuator according to claim 1, characterized in that the rotating wheel is provided with a first uneven surface, and the rotation stop member is provided with a second uneven surface that can engage with or be detached from the first uneven surface.

12. The linear actuator of claim 11, characterized in that the reduction mechanism further comprises a guide member, the rotating wheel is connected to the feed screw via the guide member, the guide member has a U-shaped opening, the rotating wheel has an insert block movably connected to the U-shaped opening, and the rotation stop member is installed on the guide member.

13. 12. The linear actuator according to claim 11, wherein the cushion mechanism further comprises a front positioning collar and a rear positioning collar, the front positioning collar and the rear positioning collar being respectively installed on both ends of the elastic body.

14. 14. The linear actuator of claim 13, further comprising at least one position limiting member for limiting a travel of said front positioning collar, said position limiting member being fixed to said outer tube.

15. 2. The linear actuator according to claim 1, further comprising at least one position limiting member for limiting a stroke of the elastic body, the cushion mechanism further including a cap, the cap being installed at one end of the elastic body away from the deceleration structure, and the position limiting member being fixed to the outer tube.

16. 2. The linear actuator according to claim 1, wherein the speed reducing structure applies braking by fastening and fixing the rotation stopper member with the elastic body.

17. 2. The linear actuator according to claim 1, wherein the reduction mechanism further comprises an actuator element and an offset wheel, the offset wheel being pivotally mounted on the actuator body and connected to the rotation stop member, the actuator element being fitted with the offset wheel and having one end fixed to the actuator body, and the rotation stop member being restricted by the actuator element and the offset wheel so as not to rotate in conjunction with the feed screw.

18. 18. The linear actuator according to claim 17, wherein the deceleration structure further comprises a reset member disposed between the rotating wheel and the rotation stop member.

19. The linear actuator of claim 17, characterized in that a locking block is provided on the rotating wheel, the rotation stop member is provided with a locking groove and a plurality of first convex teeth, the deflection wheel is provided with a plurality of second convex teeth that can rotate to mesh with each of the first convex teeth, and the locking block engages or disengages corresponding to the locking groove.

20. an actuator body including an electric motor, a lead screw, and a telescopic tube, the lead screw being driven to rotate by the electric motor, the telescopic tube having a nut for drivingly threadably engaging the lead screw; a quick release mechanism provided on the feed screw for releasing the drive of the electric motor and the feed screw; a cushion mechanism that is disposed in the actuator body and includes an elastic body and a deceleration structure, the deceleration structure having a rotating wheel driven by the feed screw and a stopper that is disposed to correspond to the rotating wheel; A linear actuator characterized in that when the nut compresses the elastic body, the elastic body deforms to mechanically connect the rotating wheel and the stopper, and the stopper brakes the rotating wheel to decelerate the feed screw.

21. 21. The linear actuator of claim 20, wherein the stopper comprises a rotation stop member and an actuator element, the actuator element is mounted on the rotation stop member, the rotation stop member is restricted by the actuator element so as not to rotate along with the lead screw, and the rotation stop member is arranged to correspond to the rotating wheel and is operably engaged or disengaged.

22. The linear actuator of claim 20, characterized in that the stopper comprises a rotation stop member, one end of the rotation stop member being fixed to the elastic body, and the other end of the rotation stop member being arranged to correspond to the rotating wheel and to be operably engaged or disengaged.

23. 21. The linear actuator of claim 20, wherein the stopper comprises a rotation stop member, an actuator element, and an offset wheel, the rotation stop member being arranged to correspond to the rotation wheel and operably engaging or disengaging therewith, the actuator element being mounted on the offset wheel, the actuator body being pivotally mounted on the offset wheel and connected to the rotation stop member, and the rotation stop member being restricted by the actuator element and the offset wheel so as not to rotate in conjunction with the feed screw.

24. an actuator body including an electric motor, a lead screw, and a telescopic tube, the lead screw being driven to rotate by the electric motor, the telescopic tube having a nut for drivingly threadably engaging the lead screw; a cushion mechanism that is disposed in the actuator body and includes an elastic body and a deceleration structure, the deceleration structure including a rotating wheel driven by the feed screw and a stopper that is disposed to correspond to the rotating wheel; A linear actuator characterized in that, when the nut compresses the elastic body, the elastic body deforms to mechanically connect the rotating wheel and the stopper, and the stopper brakes the rotating wheel to decelerate the feed screw.

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