Patent Application
20050158118
1. Field of the Invention
The present invention relates to a locking device, and more particularly to locking device to secure an inner tube in an outer tube of a telescopic tube assembly.
2. Description of Related Art
With reference to
When the relative position of the inner tube (41) is to be readjusted, the operator has to hold the inner tube (41) to prevent the inner tube (41) from slipping too far into the outer tube (40). Then the operator is able to unscrew the knob (51) and change the relative position of the inner tube (41) to the outer tube (40). However, when a distal end of the inner tube (41) is provided with a heavy load, i.e. an illuminating device, the operator has to struggle to hold the weight of the illuminating device. Therefore, assistance from the other operators is essential. That is, it is almost impossible for a lone operator to finish the adjustment of the telescopic tube assembly, especially when a weighty object is on top of the telescopic tube assembly.
To overcome the shortcomings, the present invention tends to provide an improved locking device to mitigate the aforementioned problems.
The primary objective of the present invention is to provide an improved locking device to enable a lone operator to safely finish the adjustment of the relative position of the inner tube relative to the outer tube.
Another objective of the present invention is to eliminate danger to the operator by providing a safety device to prevent excessive movement of the inner tube relative to the outer tube.
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
A locking device in accordance with the present invention includes an enclosure (20) partially securely mounted on a peripheral edge of the outer tube (40) and having a guide (201) formed on an inner face of the enclosure (20), a first space (21) defined in a side face of the enclosure (20), a first hole (22) defined through a bottom face defining the first space (21), a second hole (23) defined through the enclosure (20) to be opposite to the first hole (22) and a second space (24) defined to communicate with the second hole (23).
Furthermore, a lever (25) is received in the first space (21) and a pin (not shown) is extended through the lever (25) and into opposite side face defining the first space (21) to allow the lever (25) to be pivotally received in the first space (21). A positioning rod (26) is provided with a first distal end securely connected to a side of the lever (25) and a second distal end. The second distal end of the positioning rod (26) is provided with a head (261) corresponding to the adjusting recesses (111). A spring (262) is mounted on the positioning rod (26) and compressibly received in the first hole (22) such that when the positioning rod (26) is moved by the lever (25), the spring (262) is able to provide a recoil force to the positioning rod (26) to return the positioning rod (26). A knob (27) having a bolt (271) integrally formed with the knob (27) is screwingly extended into the second hole (23) to abut an abutting block (28) received in the second space (24) so that the outer periphery of the inner tube (11) is engaged by the abutting block (28). Especially, a safety device is mounted on the outer periphery of the inner tube (11) to prevent excessive movement of the inner tube (11) relative to the outer tube (10).
With reference to
However, during the adjustment of the telescopic tube assembly, the operator is able to use the abutting block (28) to secure the position of the inner tube (11) in the outer tube (10). That is, the operator is able to use the abutting block (28) to increase the friction between the abutting block (28) and the outer periphery of the inner tube (11) by rotating the knob (27) such that the position of the inner tube (11) in the outer tube (10) is temporarily secured. Alternatively, the operator is able to use the abutting block (28) as an auxiliary securing device to secure the position of the inner tube (11) relative to the outer tube (10).
Further, the guide (201) slidable in the guiding groove (112) is able to smoothen the sliding movement of the inner tube (11) to the outer tube (10).
Preferably, the safety device (12) which is mounted on the outer periphery of the inner tube (11) is a boss. The boss (12) is integrally formed on the outer periphery of the inner tube (11) such that excessive sliding movement of the inner tube (11) relative to the outer tube (10) is prevented.
With reference to
It is to be understood, however, that 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.
