Obstacle protection structure of a lifting column

Abstract

A lifting column comprising: a box body (10) enclosing a chamber (13); and a drive mechanism (20) disposed in the chamber (13) and comprising a motor (21) and a reduction gear (22) connected to and driven by the motor (21); a transmission mechanism (30) comprising a gear (31) connected to and driven by the reduction gear (22); and a protective structure (40) comprising a support member (41), a force sensor (45), and an elastic member (47), wherein the support member (41) is fixed to the box body (10) and configured to abut a periphery of the motor (21), the elastic member (47) is disposed on the support member (41), and the force sensor (45) is disposed on the elastic member (47);wherein, when the reduction gear (22) driving the gear (31) is locked, the motor (21) rotates around the gear (31) as a central axis to deform the elastic member (47), and the force sensor (45) detects deformation of the elastic member (47);

Description

BACKGROUND OF THE DISCLOSURETechnical Area

[0001] The technical field relates to a lifting column and in particular to an obstacle protection structure of a lifting column. Description of related technology

[0002] A lifting column is commonly used in electric beds, nursing beds, hospital beds, and electric height-adjustable tables or chairs to adjust the height or tilt angle. If the lifting column encounters an obstacle during the adjustment process, it may come into contact with the obstacle and generate a reaction force that is transmitted to the linear actuator. If the lifting column does not stop operating immediately, it may be damaged by the obstacle. If the obstacle is part of the human body, it may also cause injury.

[0003] To address the above problem, the industry has implemented protection mechanisms on the lifting columns to detect obstacles. Currently, highly sensitive obstacle protection mechanisms use obstacle detection components to convert pressure signals into electrical signals. However, if the deformation at the installation location of the obstacle detection component is comparatively small, the resulting load may be too small to trigger an obstacle warning. In some cases, sufficient load to activate the obstacle detection component is generated only after a certain period of time following a collision between the lifting column and the obstacle. Furthermore, the response speed of existing obstacle protection mechanisms is too slow and therefore does not meet the practical requirements of current applications.

[0004] In view of the above disadvantages, the inventor proposes this disclosure based on his expert knowledge and detailed research to solve the problems of the related art. SUMMARY OF REVELATION

[0005] This disclosure provides an obstacle protection structure of a lifting column in which the lifting column can interrupt its movement upon encountering an obstacle, thereby reducing the risk of collision damage to objects and increasing safety during use.

[0006] This disclosure is an obstacle protection structure comprising a box body (10), a drive mechanism (20), a transmission mechanism (30), and a protective structure (40). The box body (10) has a chamber (13). The drive mechanism (20) is arranged in the chamber (13) and comprises a motor (21) and a reduction gear (22) connected to and driven by the motor (21). The transmission mechanism (30) comprises a gear (31) connected to and driven by the reduction gear (22). The protective structure (40) comprises a support member (41), a force sensor (45), and an elastic member (47). The support member (41) is fixed to the box body (10) and is configured to abut the periphery of the motor (21), the elastic member (47) is arranged on the support member (41), and the force sensor (45) is arranged on the elastic member (47).When the reduction gear (22) driving the gear (31) is locked, the motor (21) rotates around the gear (31) as a central axis to deform the elastic member (47), and the force sensor (45) detects deformation of the elastic member (47).

[0007] This discovery offers the following advantages: The lifting column can accurately detect changes caused by external forces and provides greater protection precision and sensitivity when encountering obstacles. Additionally, the shape of the strain gauge is not restricted, and the strain gauge installation locations are more flexible. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] The features of the disclosure believed to be novel are pointed out with particularity in the appended claims. However, the disclosure itself may best be understood by reference to the following detailed description of the disclosure, which describes a number of exemplary embodiments of the disclosure, taken in conjunction with the accompanying drawings, in which: Fig. 1 illustrates a schematic assembly view of a first embodiment of this disclosure. Fig. 2 illustrates a perspective exploded schematic view of a first embodiment of this disclosure. Fig. 3 illustrates a schematic cross-sectional view of the first embodiment of this disclosure. Fig. 4 illustrates a schematic cross-sectional view of another side of the first embodiment of this disclosure. Fig. 5 illustrates a schematic assembly view of the second embodiment of this disclosure. Fig. 6 illustrates a perspective exploded schematic view of the second embodiment of this disclosure. Fig. 7 illustrates a schematic cross-sectional view of the second embodiment of this disclosure. Fig. 8 illustrates a schematic cross-sectional view of another side of the second embodiment of this disclosure. Fig. 9 illustrates a schematic assembly view of the third embodiment of this disclosure. Fig. 10 illustrates a perspective exploded schematic view of the third embodiment of this disclosure. Fig. 11 illustrates a schematic cross-sectional view of the third embodiment of this disclosure. Fig. 12 illustrates a schematic cross-sectional view of another side of the third embodiment of this disclosure. DETAILED DESCRIPTION

[0009] The technical content of this disclosure will become apparent from the detailed description of the embodiments accompanying the illustration of the accompanying drawings as follows. The embodiments and drawings disclosed herein are intended to be considered as illustrative and not restrictive.

[0010] With reference to the Fig. 1 to Fig. 4, this disclosure provides an obstacle protection structure of a lifting column 1. The lifting column 1 mainly includes a box body 10, a drive mechanism 20, a transmission mechanism 30, and a protection structure 40.

[0011] The box body 10 has a substantially rectangular shape and mainly includes a bottom plate 11 and a plurality of side plates 12 connected to the bottom plate 11. A chamber 13 is defined by the bottom plate 11 and the side plates 12. Additionally, a through hole 14 and a plurality of screw holes 15 are defined on the bottom plate 11.

[0012] The drive mechanism 20 is arranged in the chamber 13 of the box body 10 and mainly comprises a motor 21 and a reduction gear 22. The motor 21 is configured to generate both forward rotation and reverse rotation. It mainly comprises a housing 211 and associated components (not shown in the figures), such as a rotor-stator assembly housed in the housing 211. The reduction gear 22 is connected to one end of the motor 21 and mainly comprises a housing 221 and a gear (not shown in the figures) arranged within the housing 221. The gear may comprise an assembly of a worm and a worm gear or a combination of multiple spur gears and is driven by the motor 21 to generate rotational motion.A rotating element 222 is positioned at the center of the housing 221, and a socket hole 223 is defined at the center of the rotating element 222. In this embodiment, the socket hole 223 is a regular hexagonal shape, but this is not limited to this. The rotating element 222 is connected to and driven by the gear box, allowing it to rotate relative to the housing 221.

[0013] The transmission mechanism 30 includes a gear 31, a mounting seat 32, a telescopic tube 33, a plurality of screw members 34, and other associated members. One end of the gear 31 passes through the through hole 14 and is housed in the base hole 223, while the other end of the gear 31 extends into the telescopic tube 33. Two perforations 321 and a central hole (not shown in the figures) are defined in the mounting seat 32. The central hole is configured to receive the gear 31, and each perforation 321 is inserted by a screw member 34 that is fixed to a corresponding screw hole 15 in the base plate 11. The drive mechanism 20 is connected to the gear 31 exclusively via the base hole 223 of the reduction gear 22, and the side of the drive mechanism 20 on the motor 21 is neither fixed nor secured.This arrangement allows the drive mechanism 20 to rotate around the gear 31 as a central axis, causing the rear portion of the housing 211 to rotate (or oscillate) in the horizontal direction.

[0014] The protective structure 40 of this disclosure is arranged at the rear portion of the housing 211 of the motor 21. The protective structure 40 mainly comprises a support member 41, a force sensor 45, and an elastic member 47. In this embodiment, the support member 41 mainly comprises a stepped block 411, which may be a deformable member made of rubber or similar materials. A receiving groove 412 is defined in the center of the block 411 to receive the housing 211 of the motor 21. A first slot 413 and a second slot 414, which communicate with the first slot 413, are defined on the receiving groove 412 side of the block 411. The height of the first slot 413 is greater than that of the second slot 414. The block 411 is arranged in the chamber 13 of the box body 10 and is clamped and secured by two opposite side plates 12 of the box body 10.The force sensor 45 is arranged on the elastic element 47 embedded in the first slot 413. The elastic element 47 is positioned adjacent to the housing 211 of the motor 21. The force sensor 45 is arranged in the second slot 414, and a gap 415 is defined between the force sensor 45 and the wall of the second slot 414.

[0015] In this embodiment, the force sensor 45 is a resistive strain gauge 451 electrically connected to a control device (not shown in the figures). When a force is applied to the elastic element 47, the force sensor 45 is deformed, resulting in 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 component 47 is a sheet-shaped rubber pad 471.

[0016] If the lifting column 1 encounters an obstacle during the ascent or descent process, the rotation of the gear box 31 driven by the reduction gear 22 may be impeded. As a result, the current of the motor 21 increases, and the motor 21 rotates around the gear box 31 as a central axis. The torque required for the lifting column 1 to operate increases, and the pressure exerted by the reduction gear 22 on the support member 41 also increases. This pressure is transmitted through the support member 41 to the elastic member 47. The elastic member 47 deforms in response to the change in pressure, and the force sensor 45 deforms along with the elastic member 47. The force sensor 45 then generates a corresponding signal and outputs the change in the amount of deformation.

[0017] In this embodiment, the force sensor 45 is arranged between the two side plates 12 of the box body 10 and the housing 211 of the motor 21. When the lifting column 1 encounters an obstacle, the motor 21 detects changes in the force or displacement at the rear portion of the housing 211 due to the reaction torque resulting from a change in the applied torque. This enables the lifting column 1 to achieve a protective effect when it encounters obstacles. Slight variations in the torque of the motor 21 can be immediately detected by the force sensor 45. When an obstacle is encountered, the torque of the motor 21 is the first parameter to change. The detection point of the protective structure 40 acts directly on the housing 211 of the motor 21, effectively reducing the response time of the lifting column 1 and increasing the detection sensitivity.

[0018] With reference to the Fig. 5 to Fig. 8, the protective structure of the lifting column in this disclosure may be as in the previous embodiment or as described in the present embodiment. In this embodiment, the protective structure 40A mainly includes a support member 41A, a force sensor 45A, and an elastic member 47A. The support member 41A includes a U-shaped frame 42 and a plurality of screws 421. The two sides of the opening of the U-shaped frame 42 are respectively fixed to the screw holes 15 of the bottom plate 11 by screws 421. In this embodiment, the force sensor 45A is a piezoelectric sensor 452, and the elastic member 47A is a U-shaped rubber pad 472. The U-shaped rubber pad 472 is mounted on the rear portion of the housing 211 of the motor 21 and is disposed inside the U-shaped frame 42.The piezoelectric sensor 452 is positioned between the U-shaped frame 42 and the U-shaped rubber pad 472 adjacent to the curved edge of the housing 211.

[0019] If the lifting column 1 encounters an obstacle during the ascent or descent process, the rotation of the gear box 31 driven by the reduction gear 22 may be impeded. As a result, the current supplied to the motor 21 increases, and the motor 21 rotates around the gear box 31 as a central axis. The torque required for the lifting column 1 to operate increases, and the pressure exerted by the reduction gear 22 on the U-shaped rubber cushion 472 also increases. The pressure is transmitted through the U-shaped rubber cushion 472 to the piezoelectric sensor 452. The piezoelectric sensor 452 deforms in response to the pressure, and the resulting deformation generates a corresponding signal, which is then output.

[0020] With reference to the Fig. 9 to Fig.12, the protective structure of the lifting column in this embodiment is substantially the same as that in the first and second embodiments, except that the number of protective structures 40B is two. Each protective structure 40B mainly includes 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 bottom plate 11 and is disposed at the rear portion of the housing 211 of the motor 21. A notch 431 is defined at the other end of the L-shaped plate 43. The force sensor 45B in this embodiment mainly includes a Hall element (Hall sensor) 453 and a magnetic body 454. The elastic member 47B in this embodiment is a block-shaped rubber pad 473. A blind groove 4731 and an embedding groove 4732 are defined on the elastic member 47B.The Hall element 453 is positioned in the embedding groove 4732, and the magnetic body 454 is housed in the notch 431. The block-shaped rubber pad 473 is mounted on the L-shaped plate 43 via the blind groove 4731, so that the Hall element 453 is arranged correspondingly to the magnetic body 454. In addition, the magnetic body 454 can be a magnet or a magnetized element.

[0021] If the lifting column 1 encounters an obstacle during the ascent or descent process, the rotation of the gear box 31 driven by the reduction gear 22 may be hindered. As a result, the current supplied to the motor 21 increases, and the motor 21 rotates around the gear box 31 as a central axis. The torque required for the lifting column 1 to operate increases, and the pressure exerted by the reduction gear 22 on the L-shaped plate 43 also increases. This pressure is transmitted to the Hall element 453 through the block-shaped rubber cushion 473. The Hall element 453 generates a corresponding signal by detecting changes in the magnetic field strength or magnetic polarity between the Hall element 453 and the magnetic body 454 and then outputs the signal.

[0022] Furthermore, as mentioned in the above example, the number of protective structures 40B may be two. However, for certain specifications of the lifting column 1, the protective structure 40B may be implemented as a single unit. Additionally, the protective structure 40B may be arranged at the rear portion of the housing 211 of the motor 21 (not shown in the figures).

[0023] Although this disclosure has been described by means of specific embodiments, numerous modifications and variations may be made thereto by those skilled in the art without departing from the scope of the essence of this disclosure as set forth in the claims.

Claims

[1] A lifting column comprising: a box body (10) comprising a chamber (13); and a drive mechanism (20) arranged in the chamber (13) and comprising a motor (21) and a reduction gear (22) connected to and driven by the motor (21); a transmission mechanism (30) comprising a gear (31) connected to and driven by the reduction gear (22); and a protective structure (40) comprising a support member (41), a force sensor (45) and an elastic member (47), wherein the support member (41) is fixed to the box body (10) and configured to abut a periphery of the motor (21), the elastic member (47) is arranged on the support member (41), and the force sensor (45) is arranged on the elastic member (47); wherein, when the reduction gear (22) driving the gear (31) is locked, the motor (21) rotates around the gear (31) as a central axis to deform the elastic member (47), and the force sensor (45) detects deformation of the elastic member (47). [2] The lifting column according to claim 1, wherein the protective structure (40) is arranged at one end of the motor (21) remote from the reduction gear (22). [3] The lifting column according to claim 1, wherein the reduction gear (22) comprises a housing (221); a rotary member (222) is arranged on the housing (221), and a socket hole (223) connected to the gear (31) is defined on the rotary member (222). [4] The lifting column according to claim 1, wherein the support member (41) comprises a block (411); the box body (10) comprises two opposite side plates (12), and the block (411) is clamped and fixed between the two side plates (12); a receiving groove (412) is defined in the block (411), and the motor (21) is arranged in the receiving groove (412). [5] The lifting column according to claim 4, wherein a first slot (413) and a second slot (414) communicating with the first slot (413) are defined on one side of the receiving slot (412) of the block (411), the elastic member (47) is embedded in the first slot (413), and the force sensor (45) is arranged in the second slot (414). [6] The lifting column according to claim 5, wherein the elastic member (47) is a sheet-shaped rubber cushion (471) and the force sensor (45) is a resistance strain gauge (451). [7] The lifting column according to claim 1, wherein the support member (41A) comprises a U-shaped frame (42), the U-shaped frame (42) covers the motor (21) and is fixed to the box body (10), the elastic member (47A) is clamped between the U-shaped frame (42) and the motor (21), and the force sensor (45A) is positioned between the U-shaped frame (42) and the elastic member (47A). [8] The lifting column according to claim 7, wherein the elastic member (47A) is a U-shaped rubber cushion (472) arranged within the U-shaped frame (42). [9] The lifting column according to claim 7, wherein the force sensor (45A) is a piezoelectric sensor (452). [10] The lifting column according to claim 1, wherein the support member (41B) comprises an L-shaped plate (43); one end of the L-shaped plate (43) is fixed to the box body (10), and a notch (431) is defined at another end of the L-shaped plate (43); the force sensor (45B) comprises a Hall element (453) and a magnetic body (454), and an embedding groove (4732) is defined on the elastic member (47B); the Hall element (453) is positioned in the embedding groove (4732), and the magnetic body (454) is housed in the notch (431). [11] The lifting column according to claim 10, wherein the elastic member (47B) is a block-shaped rubber pad (473); a blind groove (4731) is defined on the elastic member (47B); the elastic member (47B) is mounted on the L-shaped plate (43) via the blind groove (4731), and the Hall element (453) is arranged corresponding to the magnetic body (454). [12] The lifting column according to claim 1, wherein a number of the support member (41B), a number of the force sensor (45B) and a number of the elastic member (47B) are multiple.

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