1. Field of the Invention
The present invention relates to mounting brackets, and more particularly, to a mounting bracket assembly for removably attaching a handle or the like to a surface.
2. Description of Related Art
Handles are frequently attached to various objects to allow the objects to be easily and conveniently gripped and manipulated. In many instances, it is desirable for the handle to be removable or adjustable to accommodate the particular preferences of the user. For example, left handed individuals may prefer a handle on the left side of an object while right handed individuals typically prefer a handle on the right. In either case, the handle should be firmly attached to the object so that the handle does not move, or wobble as it is pushed or pulled.
Mounting systems frequently incorporate set screws to removably attach handles and the like to various objects. Typically in such a system, a stud extends from the object and is received in a bore provided in the handle. A set screw is threaded into a hole which intersects the bore such that the end of the set screw engages the stud. Rotation of the set screw in one direction pushes the end of the set screw against the stud to hold the handle in place. Rotation of the set screw in the other direction retracts the end of the screw to release the handle.
As can be appreciated, in many set screw mounting systems, the handle is held in place primarily through friction. The end of the set screw engages the stud to create friction between the set screw and the stud. In addition, the set screw presses the stud against the interior wall of the bore to create friction between the stud and the bore. The amount of friction, and hence the strength of the force holding the handle in place depends to a large degree on the force with which the set screw presses against the stud. Inadequate pressure between the set screw and the stud may allow the handle to wobble or move undesirably.
In an effort to obtain the pressure necessary to hold the handle in place, the set screw is threaded into the hole until the end of the set screw engages the stud. Once the set screw is in contact with the stud, it is then turned an additional amount. Typically, this additional turning requires a relatively high torque and results in the elastic or, in some cases, plastic deformation of the mounting components, including the stud, the end of the set screw, or the threads. The additional turning of the set screw, after the set screw engages the stud, increases the friction between the set screw and the stud to help hold the handle in place.
In existing set screw systems, the threads of the set screw act as an inclined plane to transform rotational movement of the set screw into translational movement of the set screw. One rotation of the set screw will move the end of the set screw a distance equal to the pitch of the threads, that is, the distance between adjacent threads on the set screw. In this way, the threads of the set screw provide a mechanical advantage to help allow the set screw to be tightened.
However, in many set screw systems, the pitch of the threads on the set screw is many times larger than the amount of allowable deformation. Thus, the additional turning required to tighten the set screw is often limited to only a small fraction of a rotation. As a result, even a slight loosening of the set screw may cause the handle to loosen to the point where it wobbles, moves, or even falls off when gripped by a user. Moreover, because the additional tightening of the set screw must be accomplished with only a fraction of a turn of the set screw, a relatively high torque is required. This can make the set screw harder to install and remove, and can result in failure of the set screw head or threads.
In addition, in typical set screw mounting systems the end of the set screw contacts the stud to apply the pressure necessary to hold the handle in place. In this configuration, the force to create the pressure is usually directed axially along the set screw and is carried almost exclusively by the threads of the set screw. This can add to the difficulty of tightening the set screw adequately to hold the handle in place and can also result in damage or failure of the set screw threads.