TWI896501B - Obstacle protection structure of lifting column - Google Patents

Abstract

An obstacle protection structure of lifting column includes a box, a drive mechanism, a transmission mechanism and a protection structure. The box having a cavity. The driving mechanism is arranged in the cavity and includes a motor and a reduction gear set that is connected to the motor and driven by it. The transmission mechanism includes a spindle. The spindle is connected to the reduction gear set. The protection structure includes a support, a force transducer and an elastic part. The support is fixed to the box and formed on the periphery of the motor. The elastic part is on the support. Wherein the reduction gear set drives the movement, the motor will rotate around the spindle, causing the elastic part to deform and sense the change of the elastic part by the force sensor.

Description

Lifting column obstacle protection structure

This application relates to a technology for a lifting column, particularly a protective structure for the lifting column against obstacles.

Lifting columns are commonly used in electric beds, nursing beds, hospital beds, electric lift tables, and chairs for height or elevation adjustment. When a user encounters an obstacle while adjusting these devices, they come into contact with the obstacle, generating an interaction force that is transmitted to the linear actuator. If the lifting column does not stop immediately, the obstacle can cause damage to the column. If the obstacle is a person, this can result in injury.

To address these issues, the industry has installed obstruction detection mechanisms on lifting columns. The most sensitive current obstruction detection mechanisms utilize a component that converts pressure signals into electrical signals. However, when the deformation at the location where the obstruction detection component is mounted is small, the resulting strain is insufficient to trigger the obstruction detection component. Sufficient strain is generated to trigger the obstruction detection component only after a period of time has passed since the lifting column and the obstacle collided. Furthermore, the existing obstruction protection mechanisms have a very slow response time to obstruction, making them inadequate for current practical applications.

In view of this, the applicant has focused on the above-mentioned shortcomings of the existing technology and has conducted in-depth research and applied theoretical knowledge to try its best to solve the above-mentioned problems, which has become the goal of the applicant's improvement.

One of the purposes of this application is to provide a lifting column obstacle protection structure that can interrupt movement when it encounters an obstruction during movement, thereby reducing collision damage to objects and improving safety in use.

In order to achieve the above-mentioned purpose, the present application provides a lifting column obstacle protection structure, comprising a box body, a driving mechanism, a transmission mechanism and a protection structure, wherein the box body has a cavity; the driving mechanism is disposed in the cavity, the driving mechanism comprises a motor and a reduction gear set connected to and driven by the motor; the transmission mechanism comprises a movement, the movement is connected to the reduction gear set and driven by Its drive; the protective structure includes a support member, a force sensor and an elastic member. The support member is fixed to the box body and formed on the outer periphery of the motor. The elastic member is arranged on the support member, and the force sensor is arranged on the elastic member. When the reduction gear assembly is blocked from driving the movement, the motor will rotate around the movement, causing the elastic member to deform, and the change of the elastic member is sensed by the force sensor.

This application also offers the following benefits: It can more accurately determine changes in external forces acting on the lifting column, providing greater precision and sensitivity in protecting against obstacles. The shape of the strain gauge is not restricted, and the strain gauge can be placed in a wider range of locations.

The detailed description and technical contents of this application are described below with reference to the accompanying drawings. However, the accompanying drawings are provided for reference and illustration only and are not intended to limit this application.

Please refer to Figures 1 to 4. This application provides a lifting column obstacle protection structure, which is applied to a lifting column 1, wherein the lifting column 1 mainly includes a box body 10, a driving mechanism 20, a transmission mechanism 30 and a protection structure 40.

The box body 10 is generally rectangular and mainly includes a bottom plate 11 and a plurality of side plates 12 connected to the bottom plate 11. A cavity 13 is formed within the bottom plate 11 and the side plates 12. A through hole 14 and a plurality of screw holes 15 are also formed in the bottom plate 11.

The drive mechanism 20 is housed within the housing 13 of the housing 10 and primarily comprises a motor 21 and a reduction gear assembly 22. The motor 21 is a component capable of generating forward and reverse rotation and comprises a sleeve 211 and a rotor and stator assembly housed within the sleeve 211, along with other related components (not shown). The reduction gear assembly 22 is connected to one end of the motor 21 and primarily comprises a housing 221 and a gear assembly (not shown) housed within the housing 221. The gear assembly can be a combination of a spur gear or several spur gears, and is driven by the motor 21 to generate rotation. A rotating member 222 is disposed in the center of the housing 221. A socket 223 is disposed at the center of the rotating member 222. In this embodiment, the socket 223 is a regular hexagon, but this shape is not limiting. The rotating member 222 is connected to the aforementioned gear train and is driven by the gear train, thereby enabling the rotating member 222 to rotate relative to the housing 221.

The transmission mechanism 30 primarily comprises a movement 31, a mounting base 32, a telescopic tube 33, a plurality of screw-fastening elements 34, and other related components. One end of the movement 31 passes through the aforementioned through-hole 14 and is received in the socket hole 223, while the other end of the movement 31 extends into the telescopic tube 33. The mounting base 32 has two through-holes 321 and a center hole (not shown). The center hole is for the movement 31 to pass through, while each through-hole 321 is for a screw-fastening element 34 to pass through and lock into a respective screw hole 15 in the base plate 11. The drive mechanism 20 is connected to the movement 31 only through the socket hole 223 of the reduction gear assembly 22. The motor 21 is not fixed or locked in any way. This allows the drive mechanism 20 to be centered on the movement 31, allowing the tail section of the sleeve 211 to rotate (or shake) horizontally.

The protective structure 40 of this embodiment is mounted on the rear end of the sleeve 211 of the motor 21. The protective structure 40 primarily comprises a support member 41, a force sensor 45, and an elastic member 47. The support member 41 of this embodiment primarily comprises a stepped, deformable block 411, which can be made of a material such as rubber. A receiving groove 412 is provided in the center of the block 411 to accommodate the sleeve 211 of the motor 21. A first slot 413 and a second slot 414 communicating with the first slot 413 are provided on the side of the receiving groove 412 of the block 411. The height of the first slot 413 is greater than that of the second slot 414. The block 411 is positioned within the cavity 13 of the housing 10 and is held in place by the opposing side panels 12 of the housing 10. The force sensor 45 is mounted on a spring 47, which is embedded in the first slot 413. The spring 47 is positioned adjacent to the sleeve 211 of the motor 21. The force sensor 45 is positioned within the second slot 414, forming a gap 415 between the force sensor 45 and the wall of the second slot 414 of the block 411.

In this embodiment, the force sensor 45 is a resistive strain gauge 451, which is electrically connected to a control device (not shown). When a force is applied to the elastic member 47, the force sensor 45 deforms, causing a change in resistance. This change in resistance is processed by the control device and output as an electrical signal. In this embodiment, the elastic member 47 is a sheet of rubber pad 471.

During operation, if the lifting column 1 encounters an obstacle while ascending or descending, the rotation of the movement 31 driven by the reduction gear assembly 22 is obstructed. The current in the motor 21 increases, causing it to rotate around the movement 31. This increases the torque required to actuate the lifting column 1, increasing the pressure exerted by the reduction gear assembly 22 on the support member 41. This pressure is transmitted through the support member 41 to the elastic member 47. The elastic member 47 deforms in response to the pressure change, causing the force sensor 45 to follow suit. This change in deformation generates and outputs a corresponding signal.

In this embodiment, force sensors 45 are positioned between two corresponding side panels 12 of the housing 10 and the sleeve 211 of the motor 21. When the lifting column 1 encounters an obstacle, the motor 21 generates a reaction torque due to the torque change. This torque detects changes in the force or displacement at the end of the sleeve 211 of the motor 21, effectively protecting the lifting column 1 from obstacles. This force sensor 45 can immediately detect even slight changes in the torque of the motor 21. When encountering an obstacle, the torque of the motor 21 is the first to change. The detection point of this protective structure 40 acts directly on the sleeve 211 of the motor 21, effectively reducing the reaction time of the lifting column 1 when encountering an obstacle, thereby improving detection sensitivity.

Referring to Figures 5 to 8 , the obstacle protection structure for the lifting column of the present application can be configured as described above or as described in the present embodiment. The difference lies in the following: the protection structure 40A of the present embodiment primarily comprises a support member 41A, a force sensor 45A, and an elastic member 47A. The support member 41A of the present embodiment primarily comprises a U-shaped bracket 42 and a plurality of screws 421. The U-shaped bracket 42 is secured to the screw holes 15 of the base plate 11 on either side of its open end via the screws 421. The force sensor 45A of the present embodiment is a conductive force sensor 452. The elastic member 47A of the present embodiment is a U-shaped rubber pad 472. The U-shaped rubber pad 472 is mounted on the rear end of the sleeve 211 of the motor 21 and is formed within the U-shaped frame 42. The conductive force sensor 452 is disposed between the U-shaped frame 42 and the U-shaped rubber pad 472 and is disposed adjacent to the arc edge of the sleeve 211.

During operation, if the lifting column 1 encounters an obstacle while ascending or descending, the rotation of the movement 31 driven by the reduction gear assembly 22 is obstructed, causing the current in the motor 21 to increase, causing it to rotate around the movement 31. Simultaneously, the torque required to actuate the lifting column 1 increases, causing the pressure exerted by the reduction gear assembly 22 on the U-shaped rubber pad 472 to increase. This pressure is transmitted through the U-shaped rubber pad 472 to the conductive force sensor 452, causing it to deform under pressure. This change in deformation generates a corresponding signal, which is then output.

Referring to Figures 9 to 12 , the obstacle protection structure of the lifting column of this embodiment is substantially similar to that of the first and second embodiments described above. The difference lies in the following: This embodiment comprises two protective structures 40B, each of which primarily comprises a support member 41B, a force sensor 45B, and an elastic member 47B. The support member 41B of this embodiment is an L-shaped plate 43. One end of the L-shaped plate 43 is welded to the aforementioned base plate 11 and positioned at the end of the sleeve 211 of the motor 21. The other end of the L-shaped plate 43 is provided with a notch 431. The force sensor 45B of this embodiment primarily comprises a Hall element 453 and a magnetic body 454. In this embodiment, the elastic member 47B is a block-shaped rubber pad 473 having a blind groove 4731 and an embedding groove 4732. The Hall effect element 453 is disposed in the embedding groove 4732, and the magnetic body 454 is accommodated in the aforementioned recess 431. The block-shaped rubber pad 473 is connected to the L-shaped plate 43 via its blind groove 4731, thereby aligning the Hall effect element 453 with the magnetic body 454. The magnetic body 454 can be a magnet or a magnetized element.

During operation, if the lifting column 1 encounters an obstacle while ascending or descending, the rotation of the movement 31 driven by the reduction gear assembly 22 is obstructed, causing the current in the motor 21 to increase, causing it to rotate around the movement 31. As the torque required to operate the lifting column 1 increases, the pressure exerted by the reduction gear assembly 22 on each L-shaped plate 43 also increases. This pressure is transmitted to the Hall effect element 453 via the block rubber pad 473. The Hall effect element 453 generates and outputs a corresponding signal through changes in the magnetic field strength or polarity between it and the magnetic body 454.

In addition, in addition to the two protective structures 40B as in the above embodiment, for some lifting columns 1 of specific specifications, the protective structure 40B can also be one, and is set at the tail end of the sleeve 211 of the motor 21 (not shown).

The above description is merely a preferred embodiment of the present application and is not intended to limit the patent scope of the present application. Other equivalent variations that utilize the patent spirit of the present application should also fall within the patent scope of the present application.

1: Lifting column 10: Box 11: Base 12: Side panel 13: Receptacle 14: Through hole 15: Screw hole 20: Drive mechanism 21: Motor 211: Sleeve 22: Reduction gear assembly 221: Housing 222: Rotating element 223: Socket hole 30: Transmission mechanism 31: Movement 32: Mounting base 321: Through hole 33: Telescopic tube 34: Screw-on element 40, 40A, 40B: Protective structure 41, 41A, 41B: Support member 411: Block 412: Receptacle 413: First slot 414: Second slot 415: Spacer gap 42: U-shaped bracket 421: Screw 43: L-shaped plate 431: Notch 45, 45A, 45B: Force sensor 451: Resistive strain gauge 452: Conductive force sensor 453: Hall effect element 454: Magnetic element 47, 47A, 47B: Elastic element 471: Sheet rubber pad 472: U-shaped rubber pad 473: Block rubber pad 4731: Blind slot 4732: Mounting slot

FIG1 is a schematic diagram of the first embodiment of the present application.

FIG2 is a three-dimensional exploded view of the first embodiment of the present application.

FIG3 is a cross-sectional view of the first embodiment of the present application.

FIG4 is a cross-sectional view of the first embodiment of the present application from another direction.

FIG5 is a schematic diagram of the second embodiment of the present application.

FIG6 is an exploded view of the second embodiment of the present application.

FIG7 is a cross-sectional view of the second embodiment of the present application.

FIG8 is a cross-sectional view of the second embodiment of the present application from another direction.

FIG9 is a schematic diagram of the third embodiment of the present application.

FIG10 is an exploded view of the third embodiment of the present application.

FIG11 is a cross-sectional view of the third embodiment of the present application.

FIG12 is a cross-sectional view of the third embodiment of the present application from another direction.

1: Lifting Column

10: Box

11: Base Plate

12:Side panel

13: Cavity

14: Through hole

15: Screw hole

20: Drive mechanism

21: Motor

22: Reduction gear set

30: Transmission

31: Movement

32: Fixed seat

321: Perforation

33: Telescopic tube

34: Screw-on components

40: Protective structure

Claims (12)

A lifting column obstacle protection structure comprises: A housing having a cavity; A drive mechanism disposed in the cavity, the drive mechanism comprising a motor and a reduction gear set connected to and driven by the motor; A transmission mechanism comprising a movement connected to and driven by the reduction gear set; and A protective structure comprising a support member, a force sensor, and an elastic member. The support member is fixed to the housing and formed around the motor, the elastic member is disposed on the support member, and the force sensor is disposed on the elastic member. When the reduction gear assembly's drive to the movement is obstructed, the motor will rotate about the movement, causing the elastic member to deform. This change in the elastic member is then sensed by the force sensor. The obstacle protection structure of the lifting column as described in claim 1, wherein the protection structure is arranged at an end of the motor away from the reduction gear assembly. The obstacle protection structure of the lifting column as described in claim 1, wherein the reduction gear assembly includes a housing, the housing is provided with a rotating part, and the rotating part is provided with a socket for connecting to the movement. As described in claim 1, the obstacle protection structure of the lifting column, wherein the support member includes a block, the box body includes two corresponding side panels, the block is clamped and fixed by the two side panels and is provided with a receiving groove, and the motor is arranged in the receiving groove. As described in claim 4, the obstacle protection structure of the lifting column comprises a first slot hole and a second slot hole connected to the first slot hole on one side of the receiving slot of the block, the elastic member is embedded in the first slot hole, and the force sensor is located in the second slot hole. As described in claim 5, the obstacle protection structure of the lifting column, wherein the elastic member is a sheet-shaped rubber pad and the force sensor is a resistive strain gauge. The obstacle protection structure of the lifting column as described in claim 1, wherein the support member includes a U-shaped frame, the U-shaped frame covers the motor and is fixed to the box body, the elastic member is clamped between the U-shaped frame and the motor, and the force sensor is arranged between the U-shaped frame and the elastic member. As described in claim 7, the obstacle protection structure of the lifting column, wherein the elastic member is a U-shaped rubber pad formed in the U-shaped frame. The obstacle protection structure for a lifting column as described in claim 7, wherein the force sensor is a conductive force sensor. The obstacle protection structure of the lifting column as described in claim 1, wherein the support member includes an L-shaped plate, one end of the L-shaped plate is fixed to the box body and the other end is provided with a recess, the force sensor includes a Hall element and a magnetic body, the elastic member is provided with an embedding groove, the Hall element is arranged in the embedding groove, and the magnetic body is accommodated in the recess. As described in claim 10, the obstacle protection structure of the lifting column, wherein the elastic member is a block-shaped rubber pad and is provided with a blind groove, and the elastic member is connected to the L-shaped plate through the blind groove, so that the Hall element is configured to correspond to the magnetic body. The obstacle protection structure of the lifting column as described in claim 1, wherein the supporting parts, force sensors and elastic parts are all plural.