The invention is related to the field of hand held power tools. In particular the invention is related to an adjustable handle for a hand held circular saw.
Hand held power tools are typically designed with handle features to allow a user to conveniently grasp and manipulate the power tool. For example, known circular saws may contain two handles that may be grasped by each hand of a user during a cutting operation. A circular saw may have a first handle proximal to the rear of the circular saw that may comprise a power trigger to activate the circular saw. The circular saw may also have a second handle forward of the first handle to allow a user additional control over the circular saw during use. In what may be known as a “right-handed” circular saw, the user may grasp the first handle with his or her right hand and grasp the second handle with his or her left hand during use. The second handle may be a knob or elongated handle fixed to the outer housing of the circular saw.
Hand held power tools may be adjusted to different orientations during use or may be operated in several different orientations. For example, some circular saws allow users to perform “bevel” cuts. In such an operation, the circular saw may be rotated at an angle with respect to a typically horizontal base to perform a cut at, for example, a 30° or 45° angle. Although, the orientation of operation of the power tool may change, the handles remain at fixed angles with respect to the power tool housing. This can cause the user to grasp the power tool at angles awkward to a user. The varying angles of operation of the hand held power tools can cause discomfort and place wrist stress on the user. The fixed angle of the handles can also interfere with the line of sight with the work piece during operation when the power tool is in some orientations.
Thus, the present invention is directed to providing an adjustable handle for use with hand held power tools that can be easily adjusted without disrupting a work procedure. The present invention is also directed to an adjustable handle that optimizes a user's line of sight and grip position, that promotes comfort and that reduces wrist stresses.
In one aspect of the invention, a power tool has a housing having a motor for driving a tool. The power tool also has a first handle attached to the housing which has an elongated body defining a longitudinal axis. The elongated body is capable of rotation about the longitudinal axis. The first handle also has a locking member wherein said locking member has internal threads and is operable to restrict rotational motion of the first handle. The power tool further comprises a second handle attached to the housing.
In another aspect of the invention a method of adjusting a handle for a power tool is provided. In one step of the method a power tool is provided having a housing and a first handle and a second handle connected to the housing. In another step the first handle is rotated about a longitudinal axis of the handle to a desired position. In another step the first handle is locked in the desired position with a locking member. In yet another step, the first handle and second handle are grasped during operation of the power tool.
In yet another aspect of the invention, an adjustable handle for a power tool has an elongated body defining a longitudinal axis. The elongated body further has a male selector member and a female selector member having a recess. The male selector member and female selector member are operable to engage each other and are rotatable with respect to each other about the longitudinal axis. The adjustable handle for a power tool also has a grip section connected with an end of the elongated body and a locking member rotatable with respect to the elongated body and operable to rotate between a first position and a second position. When the locking member is in a first position the male selector member and the female selector are operable to be rotated with respect to each other. When the locking member is in a second position the male selector member and the female selector are releasably fixed with respect to each other.
Advantages of the present invention will become more apparent to those skilled in the art from the following description of the preferred embodiments of the invention which have been shown and described by way of illustration. As will be realized, the invention is capable of other and different embodiments, and its details are capable of modification in various respects. Accordingly, the drawings and description are to be regarded as illustrative in nature and not as restrictive.
A portable power tool 10 is shown in
In the illustrated embodiment, electrical power is provided to the motor by means of an electrical cord 28 having an electrical plug attachable to a conventional household electrical outlet. Alternatively, a battery powered version of the saw could be made using a rechargeable battery pack and a DC electric motor.
The adjustable handle 100 according to one embodiment is partially shown in more detail in
The adjustable handle 100 also has a pivot portion 130 connected with the end opposite the end of the elongated body 110 connected with the grip section 120. The pivot portion 130 engages the housing through an opening 210 in the handle mounting portion 200 of the housing. The pivot portion 130 is preferably substantially cylindrical, but also defines a substantially planar mating surface 135. The pivot portion 130 also has a ring member 137 that projects radially from the pivot portion 130. The ring member 137 further defines a stop surface 138. The ring member 137 may be formed integrally with the pivot portion 130, or the ring member 137 may be a separate piece fixedly attached to the pivot portion 130.
In one embodiment, the elongated body 110 provides the user a manner to adjust the adjustable handle 100 into one of a plurality of predefined positions. In the embodiment of
The adjustable handle 100 also defines a locking member 150. In the embodiment of
The handle mounting portion 200 of the housing defines an opening 210 to accommodate the adjustable handle. In the embodiment of
In operation of one embodiment of the adjustable handle 100 of the power tool, the user rotates the adjustable handle 100 around the longitudinal axis x to place the adjustable handle 100 in a desired position. In one embodiment, the user places the adjustable handle 100 into one of a plurality of predetermined positions corresponding to the different positions of the selector recesses 190 of the recess 188. The user then rotates the locking collar 150 from a first, release position to a second, lock position to lock the adjustable handle 100 in place. Rotation of the locking collar 150 causes the internal threads of the locking collar 150 to engage the external threads 140 of the elongated body 110, creating an axial force along the longitudinal axis x. In the embodiment of
In another embodiment, the female selector member 186 need not have a plurality of selector recesses 190. In this embodiment, the selector projection 184 can rotate within the recess 188 without being required to engage selector recesses 190 that correspond to predetermined handle positions. The user may thus select the position of the adjustable handle 100 according to a desired position and then lock the adjustable handle 100 with the locking member according to the procedures described above.
Although specific embodiments have been illustrated and described herein, it will be appreciated by those of ordinary skill in the art that a variety of alternate and/or equivalent implementations may be substituted for the specific embodiments shown and described without departing from the scope of the present invention. This application is intended to cover any adaptations or variations of the specific embodiments discussed herein. Therefore, it is intended that this invention be limited only by the claims and the equivalents thereof. For example, while specific reference has been made to the use of a circular saw, the devices and methods in accordance with principles of the present invention are equally applicable to other hand held power tools.