Actuator with worm gear positioning mechanism

Abstract

An actuator having a worm gear positioning mechanism, the actuator comprising: an outer casing (10); a motor (20) comprising a worm shaft (21) and arranged in the outer casing (10); a gear arrangement (30) partially arranged in the outer housing (10) and comprising a guide threaded rod (31), a worm gear (32) and a bearing (33), wherein the bearing (33) surrounds one end of the guide thread rod (31) to support the guide thread rod (31) in the outer housing (10), wherein the worm wheel (32) surrounds the guide threaded rod (31) and engages with the worm shaft (21), and the worm wheel (32) is formed as an annular element (321) having an inner peripheral surface (322); an outer sleeve (40) partially secured in the outer casing (10) and having an outer peripheral surface (41) at one end of the outer sleeve (40) and attached to the inner peripheral surface (322) of the worm wheel (32), wherein the worm wheel (32) is positioned between the worm shaft (21) and the outer sleeve (40) in the radial direction; and a telescopic tube (50) arranged in the outer sleeve (40) and comprising an inner sleeve (51) and a screw nut (52) connected to the inner sleeve (51), wherein the screw nut (52) is movably screwed to the guide threaded rod (31) in order to ensure that the inner sleeve (51) is linearly movable relative to the outer sleeve (40).

Description

BACKGROUND OF THE DISCLOSURETechnical Area

[0001] The present disclosure relates to an actuating element, in particular to an actuating element having a worm gear positioning mechanism. Description of related technology

[0002] An actuator can be actuated without being powered by a gas or liquid and can offer the advantages of compact volume, low noise during operation, and minimal pollution to the surrounding environment. Therefore, the actuator is widely used in various fields, such as homes, industrial sites, medical facilities, and agricultural areas.

[0003] A gear assembly of the actuator of the related art includes a lead screw rod, a worm gear, a rear bearing, and a positioning bearing. The worm gear, the rear bearing, and the positioning bearing are arranged sequentially on the lead screw rod, and the worm gear is arranged between the rear bearing and the positioning bearing. The lead screw rod and the worm gear are supported in a casing by the rear bearing and the positioning bearing.

[0004] However, the installation costs of the positioning bearing have long been a concern. Some suppliers use low-cost and low-quality positioning bearings as replacements, which significantly shortens the service life of the actuator. Other suppliers can directly save costs by not installing the positioning bearing, which results in poor stability of the guide screw rod during operation.

[0005] Accordingly, the applicant of the present disclosure has focused on improving the mentioned deficiencies. SUMMARY OF REVELATION

[0006] The present disclosure is to provide an actuator with a worm gear positioning mechanism, wherein a worm gear is radially positioned, thereby saving the installation cost of a positioning bearing, stable operation, and compact internal structure.

[0007] Accordingly, the present disclosure provides an actuator with a worm gear positioning mechanism including a shell housing, a motor, a gear assembly, an outer tube, and a telescopic tube. The motor is disposed within the shell housing and has a worm rod. A portion of the gear assembly is disposed within the shell housing. The gear assembly includes a lead screw rod, a worm gear, and a bearing. The bearing is disposed at one end of the lead screw rod to support the lead screw rod within the shell housing. The worm gear is configured to surround the lead screw rod and engages the worm rod for transmission. The worm gear includes an annular member. The annular member has an inner circumferential surface. A portion of the outer tube is fixed to the shell housing.One end of the outer tube has an outer peripheral surface that is attached to the inner peripheral surface. The worm gear is positioned between the worm rod and the outer tube in a radial direction. The telescopic tube is arranged in the outer tube and has an inner tube and a screw nut connected to the inner tube. The screw nut is movably screwed to the guide thread rod to enable the inner tube to move linearly relative to the outer tube.

[0008] Advantages achieved by the present disclosure are as follows. With each positioning column and through hole engaged and secured, the outer tube is stably mounted in the casing. By connecting the worm gear to the outer tube, the operation of the lead screw rod is more reliable. By firmly attaching each braking component to each convex column, a torsion spring is driven to generate radial compression to achieve a braking effect. By arranging each sealing ring, internal electrical components are prevented from being affected by moisture and protected from damage. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] The features of the disclosure which are believed to be novel are set forth 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 numerous exemplary embodiments of the disclosure, taken in conjunction with the accompanying drawings, in which: Fig. 1 is a schematic view showing the arrangement of the actuator with a worm gear positioning mechanism according to the present disclosure; Fig. 2 is a perspective view showing the arrangement of the actuator with a worm gear positioning mechanism according to the present disclosure; Fig. 3 is an exploded view showing the gear assembly and outer tube according to the present disclosure; Fig. 4 is an exploded view showing the actuator with a worm gear positioning mechanism according to the present disclosure; Fig. 5 is a cross-sectional view showing the assembled actuator with a worm gear positioning mechanism according to the present disclosure; and Fig. 6 is another cross-sectional view showing the assembled actuator with a worm gear positioning mechanism according to the present disclosure. ACCURATE DESCRIPTION OF REVELATION

[0010] The technical contents of this disclosure will become apparent from the detailed descriptions of embodiments accompanied by the illustration of related drawings as follows. It is intended that the embodiments and drawings disclosed herein be considered illustrative rather than restrictive.

[0011] In the Fig. 1 to Fig. 6, the present disclosure provides an actuator with a worm gear positioning mechanism including a shell housing 10, a motor 20, a gear assembly 30, an outer tube 40, a telescoping tube 50.

[0012] As in Fig. 1, Fig. 2 and Fig. 3, the shell housing 10 is made of a material such as plastic or an alloy material. The shell housing 10 mainly includes a lower housing member 11 and an upper housing member 12. The lower housing member 11 has a tubular housing 111 and a base 112 extending from the tubular housing 111. A first receiving portion 113, a second receiving portion 114, and a third receiving portion 115 are formed sequentially from right to left in the base 112. A lower positioning column 116 extending from the base 112 is disposed at a central location of the third receiving portion 115. The upper housing member 12 is correspondingly engaged with the base 112 of the lower housing member 11. An upper positioning column 121, corresponding to the lower positioning column 116, extends from the upper housing member 12.

[0013] In some embodiments, a first semicircular recess 117 is formed at a tip end of the base 112, and a second semicircular recess 122, corresponding to the first semicircular recess 117, is formed on the upper housing member 12 to collectively define a circular recess. Additionally, a third semicircular recess 118 is formed at a distal end of the base 112, and a fourth semicircular recess 123, corresponding to the third semicircular recess 118, is formed on the upper housing member 12 to collectively define another circular recess.

[0014] The motor 20 is an electric motor capable of forward and reverse rotation. The motor 20 is arranged in the tubular housing 111 of the casing 10. The motor 20 includes a worm gear 21. The worm gear 21 is formed in the second receiving area 114 of the base 112.

[0015] In the Fig. 3 to Fig.6, a part of the gear assembly 30 is arranged in the first receiving portion 113 and the second receiving portion 114 of the casing 10, another part of the gear assembly 30 extends in a direction away from the casing 10. The gear assembly 30 mainly includes a lead screw rod 31, a worm gear 32, and a bearing 33. The bearing 33 is arranged at one end of the lead screw rod 31, and the lead screw rod 31 is supported via the base 112 of the casing 10. The worm gear 32 surrounds the lead screw rod 31 and is in mutual engagement with the worm rod 21 for transmissions. The worm gear 32 moves with the lead screw rod 31. In addition to having a gear portion, the worm gear 32 further has a ring member 321. The ring member 321 extends from one side of the gear portion.As such, the overall structural strength of the worm gear 32 is increased. The ring member 321 has an inner circumferential surface 322. A first convex column 323 and a second convex column 324 extend from two sides of an axial core of the worm gear 32. The second convex column 324 extends from the worm gear 32 in a direction away from the first convex column 323.

[0016] A part of the outer tube 40 is fixed in the third receiving portion 115 of the casing 10, and another part of the outer tube 40 extends in a direction away from the casing 10. One end of the outer tube 40 has an outer peripheral surface 41 that is attached to the inner peripheral surface 322 of the ring member 321, whereby the worm gear 32 is positioned between the worm rod 21 and the outer tube 40 in the radial direction. The outer tube 40 has two through holes 42 located in the third receiving portion 115. One of the through holes 42 is arranged corresponding to the lower positioning column 116 to be mutually engaged and fixed. The other penetrated hole 42 is arranged corresponding to the upper positioning column 121 to be mutually engaged and fixed.

[0017] The telescopic tube 50 is arranged within the outer tube 40. The telescopic tube 50 mainly includes an inner tube 51 and a screw nut 52 connected to the inner tube 51. The screw nut 52 is movably screwed to the guide threaded rod 31 to enable the inner tube 51 to move linearly in extension or retraction relative to the outer tube 40.

[0018] In some embodiments, the actuator with the worm gear positioning mechanism 32 of the present disclosure further includes a rear support 60. The rear support 60 covers the bearing 33 and is co-located within the first receiving area 113 of the base 112. The rear support 60 has an annular mounting slot 61.

[0019] In some embodiments, the actuator with worm gear positioning mechanism 32 further includes a first braking component 70 and a second braking component 75. The first braking component 70 is annularly and fixedly disposed on an outer surface of the first convex column 323, and one end of it is fixed to the rear bracket 60. The second braking component 75 is annularly and fixedly disposed on an outer surface of the second convex column 324, and one end of it is fixed to the outer tube 40. In some embodiments, the first braking component 70 and the second braking component 75 are torsion springs. As the first convex column 323 and the second convex column 324 rotate, the torsion spring is driven to generate radial compression to achieve a braking effect.

[0020] In some embodiments, the actuator with worm gear positioning mechanism 32 further includes a first sealing ring 80 and a second sealing ring 85. The first sealing ring 80 is disposed in the first semicircular recess 117, the second semicircular recess 122, and the annular mounting slot 61. The second sealing ring 85 surrounds an outer surface of the outer tube 40 and is disposed in the third semicircular recess 118 and the fourth semicircular recess 123.

[0021] While this disclosure has been described with reference to specific embodiments, numerous changes and variations may be made by those skilled in the art without departing from the scope and spirit of this disclosure as set forth in the claims

Claims

[1] An actuating element with a worm gear positioning mechanism, wherein the actuating element comprises: an outer casing (10); a motor (20) comprising a worm shaft (21) and arranged in the outer housing (10); a gear assembly (30) which is partially arranged in the outer housing (10) and comprises a guide threaded rod (31), a worm gear (32) and a bearing (33), wherein the bearing (33) surrounds one end of the guide threaded rod (31) to support the guide threaded rod (31) in the outer housing (10), wherein the worm wheel (32) surrounds the guide threaded rod (31) and engages with the worm shaft (21), and the worm wheel (32) is designed as an annular element (321) with an inner circumferential surface (322); an outer sleeve (40) which is partially attached in the outer housing (10) and has an outer circumferential surface (41) at one end of the outer sleeve (40) and is attached to the inner circumferential surface (322) of the worm gear (32), wherein the worm wheel (32) is positioned radially between the worm shaft (21) and the outer sleeve (40); and a telescopic tube (50) arranged in the outer sleeve (40) comprising an inner sleeve (51) and a screw nut (52) connected to the inner sleeve (51), wherein the screw nut (52) is movably screwed to the guide threaded rod (31) to ensure that the inner sleeve (51) is linearly movable relative to the outer sleeve (40). [2] The actuating element according to claim 1, which further comprises a rear support (60) that partially covers the bearing (33) in order to be jointly received in the outer housing (10). [3] The actuating element according to claim 2, which further comprises a first brake component (70), wherein the worm gear (32) comprises a first convex support (323) extending therefrom, wherein the first brake component (70) is arranged annularly on the first convex support (323) and one end of the first brake component (70) is attached to the rear support (60). [4] The actuating element according to claim 3, which further comprises a second brake component (75), wherein the worm gear (32) comprises a second convex support (324) extending from it in a direction opposite to the first convex support (323), wherein the second brake component (75) is arranged annularly on the second convex support (324) and one end of the second brake component (75) is attached to the outer sleeve (40). [5] The actuating element according to claim 2, which further comprises a first sealing ring (80), wherein the outer housing (10) comprises a lower housing element (11) and an upper housing element (12) which engage accordingly with the lower housing element (11), wherein the lower housing element (11) has a first semicircular recess (117), the upper housing element (12) comprises a second semicircular recess (122) corresponding to the first semicircular recess (117), and the rear support (60) comprises an annular mounting slot (61), wherein the first sealing ring (80) is arranged in the first semicircular recess (117), the second semicircular recess (112), and the annular mounting slot (61). [6] The actuating element according to claim 5, which further comprises a second sealing ring (85), wherein the lower housing element (11) comprises a third semicircular recess (118) and the upper housing element (12) comprises a fourth semicircular recess (123) corresponding to the third semicircular recess (118), wherein the second sealing ring (85) is designed to enclose the outer sleeve (40) and is arranged in the third semicircular recess (118) and the fourth semicircular recess (123). [7] The actuating element according to claim 1, wherein the outer housing (10) comprises a lower housing element (11) and an upper housing element (12) which engages accordingly with the lower housing element (11), wherein the lower housing element (11) comprises a tubular housing (111) and a base (112) extending from the tubular housing (111) and the motor (20) is partially arranged in the tubular housing (111). [8] The actuating element according to claim 7, wherein a first receiving area (113), a second receiving area (114) and a third receiving area (115) are successively defined in the base (112), wherein the bearing (33) is arranged in the first receiving area (113), the worm gear (32) is arranged in the second receiving area (114) and the outer sleeve (40) is partially arranged in the third receiving area (115). [9] The actuating element according to claim 8, wherein the base (112) comprises a lower positioning support (116) extending from there into the third receiving area (115), wherein the upper housing element (12) has an upper positioning support (121) extending from there and corresponding to the lower positioning support (116), wherein the outer sleeve (40) has several through holes (42) arranged in the third receiving area (115) of the base (112), wherein the through holes (42) are arranged corresponding to the lower positioning support (116) and the upper positioning support (121) in order to be in mutual engagement and secured. [10] The actuating element according to claim 1, wherein the outer housing (10) comprises a lower housing element (11) and an upper housing element (12) which engages with the lower housing element (11), wherein the lower housing element (11) has a lower positioning support (116) extending therefrom, and the upper housing element (12) has an upper positioning support (121) extending therefrom and corresponding to the lower positioning support (116), wherein the outer sleeve (40) has several through holes (42) which are arranged corresponding to the lower positioning support (116) and the upper positioning support (121) in order to engage with each other and be secured.

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