Electric support rod

This disclosure is directed to an electric support rod having a driving assembly, an actuating assembly, and a bearing. The driving assembly has a first outer tube and a driving unit in the first outer tube. An internal thread is configured in the first outer tube. The actuating assembly has a second outer tube and a transmission screw rod in the second outer tube. Multiple elastic arms axially are extended from the second outer tube and arranged spacedly around the transmission screw rod. Each elastic arm has an outer thread structure and a hook portion. The second outer tube is inserted in the first outer tube, the internal thread is screwed with the outer thread structure. One end of the transmission screw rod protrudes from the second outer tube to engage the driving unit. The bearing sheathes the transmission screw rod and the hook portion latches the bearing.

BACKGROUND OF THE DISCLOSURE

Technical Field

This disclosure is directed to an electric support rod of a tailgate of a car and in particular to a two-segment electric support rod which is easy to be assembled.

Description of Related Art

A related-art electric tailgate of a car is supported and driven by electric support rods arranged at two sides of a door frame. The electric support rod has an electric motor and a telescopic pole linked with the electric motor, the telescopic pole can be driven to telescope by controlling the electric motor to rotate so as to open or close the tailgate.

In general, the electric support rod has an outer tube, and the telescopic pole and the electric motor are inserted in the outer tube. The telescopic pole has a screw rod connected to the electric motor, and a bearing for fixing the screw rod is arranged between the screw rod and the outer tube. An inner edge of the bearing needs to be tightly fit with the screw rod and an outer edge of the bearing needs to be tightly fit with an inner wall of the outer tube. Furthermore, the outer tube is relatively long, and the bearing is therefore difficult to be assembled.

In view of the above drawbacks, the inventor proposes this disclosure based on his expert knowledge and elaborate researches in order to solve the problems of related art.

SUMMARY OF THE DISCLOSURE

This disclosure is directed to a two-segment electric support rod which is easy to be assembled.

This disclosure is directed to an electric support rod having a driving assembly, an actuating assembly, and a bearing. The driving assembly has a first outer tube and a driving unit accommodated in the first outer tube, the first outer tube has a first engaging end and an internal thread arranged on an inner surface of the first engaging end. The actuating assembly has a second outer tube and a transmission screw rod inserted in the second outer tube, the second outer tube has a second engaging end and a plurality of elastic arms. The elastic arms are axially extended from the second engaging end and disposed spacedly around the transmission screw rod. Each elastic arm has an internal surface facing the transmission screw rod and an external surface opposite to the transmission screw rod. An outer thread structure is arranged on the external surface, a hook portion is disposed protrusively from the internal surface. The second engaging end is inserted in the first engaging end, the internal thread is screwed with the outer thread structure, and one end of the transmission screw rod protrudes from the second outer tube to be engaged the driving unit. The bearing is adapted to sheathe the transmission screw rod, and the hook portion latches an outer edge of the bearing.

According to the electric support rod of this disclosure, the outer edge of the bearing is attached on the internal surface of the elastic arm.

According to the electric support rod of this disclosure, the actuating assembly further has a telescopic set inserted in the second outer tube and adapted to sheathe the transmission screw rod, and the telescopic set has a nut screwed with the transmission screw rod.

According to the electric support rod of this disclosure, the transmission screw rod has a transmission thread, the transmission screw rod has a tenon laterally inserted in the transmission screw rod, and the bearing is clamped between one end of the transmission thread and the tenon.

According to the electric support rod of this disclosure, each outer thread structure has a plurality of thread segments disposed parallelly, and the thread segments of the outer thread structure are configured with the internal thread in the same helix line.

According to the electric support rod of this disclosure, an outer surface of the second outer tube has an external thread extended from any one of the outer thread structures, and the external thread and the thread segments of the outer thread structures are configured with the internal thread in the same helix line. The outer surface of the second outer tube has a connecting surface, the connecting surface is attached on the inner surface of the first outer tube. The external thread is disposed between the connecting surface and the outer thread structure and is screwed with the internal thread. The connecting surface is a curved annular surface surrounding a lateral side of the second outer tube.

Accordingly, the driving unit of the electric support rod of this disclosure may be preassembled to the first outer tube. The telescopic set, the transmission screw rod and the bearing may be preassembled to the second outer tube, and then the first outer tube may be engaged with the second outer tube so that the transmission screw rod is power connected with the driving unit and the bearing is positioned.

DETAILED DESCRIPTION

According to an embodiment of this disclosure shown inFIGS.1to5, this disclosure is directed to an electric support rod having a driving assembly100, an actuating assembly200and a bearing300.

According to this embodiment, the driving assembly100has a first outer tube110and a driving unit130accommodated in the first outer tube110. The first outer tube110has a first engaging end111, the first engaging end111has an opening101, and an internal thread112is arranged on an inner surface of the first engaging end111. According to this embodiment, the driving unit130at least has a motor.

The actuating assembly200has a second outer tube210and a transmission screw rod230inserted in the second outer tube210. The second outer tube210has a second engaging end211, and a plurality of elastic arms220. The elastic arms are extended from the second engaging end211along an axial direction of the second outer tube210and disposed around the transmission screw rod230at intervals. Each elastic arm220has an internal surface220afacing the transmission screw rod230and an external surface220bopposite to the transmission screw rod230, an outer thread structure222is arranged on each external surface220b, a hook portion223is disposed protrusively on each internal surface220a. Each outer thread structure222has a plurality of thread segments222adisposed parallelly, each thread segment222ais extended across the elastic arm220where the thread segment222ais located, and the thread segments222aare configured with the internal thread112in the same helix line.

An outer surface of the second outer tube210has a connecting surface224and an external thread221, the connecting surface224is a curved annular surface surrounding a lateral side of the second outer tube210, and the external thread221is configured between the connecting surface224and the outer thread structures222. The external thread221extended from any one of the outer thread structures222, and the external thread221and the thread segments222aof the outer thread structures222configured with the internal thread112in the same helix line.

The transmission screw rod230has a transmission thread231, the transmission screw rod230is provided with a tenon232which is inserted into the transmission screw rod230along a lateral direction of the transmission screw rod230, and the bearing300is clamped between one end of the transmission thread231and the tenon232. According to this embodiment, the tenon232is a C-clip, but scope of this disclosure should not be limited to the aforementioned embodiment. For example, the tenon232may be a pin inserted into the transmission screw rod230.

The actuating assembly200further has a telescopic set240inserted in the second outer tube210and adapted to sheathe the transmission screw rod230. The telescopic set240has a plurality of tubes movably sheathed with one another, thereby telescoping for varying a length of the telescopic set240. Moreover, the telescopic set240has a nut241screwed with the transmission screw rod230, the nut241is connected to one of the tubes, the nut241is moved along a longitudinal direction of the transmission screw rod230when the transmission screw rod230is rotated, so as to drive the telescopic set240to telescope.

According to this embodiment, the bearing300is of a ring shape, the bearing300sheathes the transmission screw rod230and an inner edge thereof is tightly fit with the transmission screw rod230. An outer diameter of the bearing300is fit with a ring enclosed by the internal surfaces220aof the elastic arm220. The bearing300is put into the second outer tube210along a longitudinal direction of the second outer tube210, the bearing300presses the hook portions223when moves into the second outer tube210so as to outward push the elastic arms220. The bearing300passes the hook portions223and then the elastic arms220return inward so that an outer edge of the bearing300is attached with the internal surfaces220aof the elastic arms220, and the hook portions223latch the outer edge of the bearing300to fix the bearing300in the second outer tube210.

The second engaging end211is inserted into the first engaging end111through the opening101, the internal thread112is screwed with the outer thread structures222, and the external thread221is screwed with the internal thread112, so that the first outer tube110is connected with the second outer tube210. One end of the transmission screw rod230protrudes from the second outer tube210to be engaged the driving unit130, and the transmission screw rod230and the motor of the driving unit130are co-axially disposed. The first outer tube110and the second outer tube210may be further welded to fix with each other. According to this embodiment, the connecting surface224is attached with the inner surface of the first outer tube110, namely attached to a region between the opening101and the internal thread112, and the connecting surface224may be fixed with the inner surface of the first outer tube110via laser welding, high frequency bonding, binder, etc.

Accordingly, the driving unit130of the electric support rod of this disclosure may be pre-assembled to the first outer tube110, the telescopic set240, the transmission screw rod230and the bearing300may be pre-assembled to the second outer tube210, and then the first outer tube110may be engaged with the second outer tube210so as to link the transmission screw rod230with the driving unit130. The second outer tube210has elastic arms220, the elastic arm220has the hook portion223and the outer thread structure222respectively disposed at inside and outside thereof, the bearing300may be fixed by the hook portion223when move into the second outer tube210so as to avoid loosening for a convenience of engaging the second outer tube210with the first outer tube110. Moreover, the second outer tube210is engaged with the first outer tube110, and then the elastic arm220is positioned by the inner surface of the first outer tube110so as to tightly fit the outer edge of the bearing.