Patent Application
20180252034
The present invention relates to a torsion assembly, and more particularly to a torsion assembly for a curtain to provide a torsion force to a curtain fabric and to reel the curtain fabric around an axle automatically.
A curtain, such as a vehicle curtain, substantially comprises a curtain fabric connected with and reeled around an axle. The axle with the reeled curtain fabric is mounted in a tube, and the curtain fabric can be expanded or reeled around the axle via a slot defined in the tube. To automatically reel the curtain fabric around the axle, a torsion assembly is mounted in the tube to provide a torsion force to the axle.
A conventional torsion assembly has the following types.
DE 10 2007 051 056B3, referred to as the '056 patent hereafter, discloses a torsion assembly that comprises a connection member and a torsion spring. The connection member is composed of multiple components. The torsion spring has an L-shaped connection leg, and the L-shaped connection leg is connected with and clamped by the connection member.
CN 102041964B, referred to as the '964 patent hereafter, discloses a rolling rod for a curtain having a torsion assembly. The torsion assembly of the '964 patent has a connection member and a torsion spring. The connection member of the '964 patent is formed as a single part and has a block protruding from the connection member. The torsion spring is spiral, is mounted around the connection member, and is connected with the block on the connection member with one end of the torsion spring. The structure of the connection member of the '964 patent is simpler than that of the '056 patent. However, in assembling the torsion spring with the connection member, to connect one end of the torsion spring with the block on the connection member and further to mount the torsion spring around the connection member is troublesome.
In addition, the torsion spring of another type of the conventional torsion assembly has a connection leg that is formed L-shaped or U-shaped. The connection member has a holding hole to connect with the connection leg of the torsion spring. To assemble the connection leg of the torsion spring with the holding hole in the connection member is easier than to mount an end of the torsion spring around the connection member as the '056 patent.
A U-shaped connection leg of a torsion spring can provide a firmer connection with the connection member than that between the L-shaped connection leg and the connection member. However, to fit and connect with the U-shaped connection leg, the holding hole in the connection member has to be elongated. However, after the torsion assembly is mounted in the tube of a curtain, the U-shaped connection leg is easily deformed and escapes from the holding hole when the torsion spring is applied with a force along an axis of the torsion spring.
To overcome the shortcomings, the present invention tends to provide a torsion assembly to mitigate or obviate the aforementioned problems.
The main objective of the invention is to provide a torsion assembly that can prevent a connection leg of a torsion spring from escaping from a connection member.
The torsion assembly has a connection member and a torsion spring. The connection member has a shaft, a connection segment, and a holding protrusion. The shaft has an end. The connection segment is formed on the end of the shaft and has a connection hole and a holding groove. The connection hole is radially defined through the connection segment and has a connection surface formed in a side of the connection hole that is adjacent to the shaft. The holding groove is defined in the connection surface of the connection hole. The holding protrusion is formed in the connection hole and has an end extending toward the connection surface of the connection hole. The torsion spring has a spring body and a connection leg. The spring body is mounted around the shaft of the connection member and has an end and an axis. The connection leg is formed on and extends from the end of the spring body, is connected with the connection segment of the connection member, and has a rod segment, a bent segment, and a hook segment. The rod segment is formed on and protrudes from the end of the spring body, is parallel with the axis of the spring body, and has an end opposite the spring body. The bent segment is connected with the end of the rod segment, is perpendicular to the rod segment, extends toward the axis of the spring body, is held in the holding groove in the connection member to be kept from escaping out of the holding groove by the holding protrusion, and has an end opposite the rod segment. The hook segment is connected with the end of the bent segment, is perpendicular to the bent segment, and extends toward the spring body. The rod segment and the hook segment are located respectively at two diametrical ends of the connection segment of the connection member.
Other objects, advantages and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.
With reference to
With reference to
Preferably, the holding protrusion 13 is formed on and protrudes from the back surface 126 of the connection hole 123 and extends toward the holding groove 125 defined in the connection surface 124. The end of the holding protrusion 13 that is adjacent to the holding groove 125 is a free end. The holding protrusion 13 is bendable and resilient to allow the holding protrusion 13 to return to an original status with resilience. With reference to
With reference to
With reference to
Preferably, the width of the holding groove 125 is equal to or slightly larger than the diameter of the bent segment 222. The width of the first positioning groove 14 is equal to or slightly larger than the diameter of the rod segment 221. The width of the second positioning groove 15 is equal to or slightly larger than the diameter of the hook segment 223.
The torsion assembly in accordance with the present invention is mounted in a tube of a curtain and is connected with an axle of the curtain. When a curtain fabric of the curtain is expanded, the torsion spring 20 is twisted. When the curtain fabric is released, the torsion spring 20 can provide a torque to the axle and to automatically reel the curtain fabric around the axle.
The torsion spring 20 has a continuously-bent connection leg 22 to connect with the connection hole 123 in the connection segment 12 of the connection member 10. With the arrangement of the holding protrusion 13, the connection leg 22 of the torsion spring 20 is prevented from escaping from the connection hole 123 easily. Therefore, the connection between the torsion spring 20 and the connection member 10 is enhanced and firm. Thus, the torsion assembly in accordance with the present invention can keep providing an excellent torque to the axle for a long time.
Even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.
