The above type of the working machine includes a machine body, a handle rotatably attached to the machine body, a throttle lever provided in the handle for adjusting a motive power output from the working machine, and a throttle lock lever for locking the throttle lever.
For practical use, it is only necessary that the power working machine include, as well as the throttle lever and the throttle lock lever, a locking mechanism provided in the machine body for locking the handle to stop rotation of the handle and an unlocking lever provided in the machine body for unlocking the locking mechanism.
The locking mechanism is operable together with a throttle wire, and the power working machine including such a locking mechanism is well known from, for example, JP-A-11-28683. The power working machine disclosed in JP-A-11-28683 will be discussed with reference to FIG. 12 hereof.
The disclosed, conventional power working machine designated at 200 includes a machine body 201, a handle 202 rotatably attached to the machine body 201, a throttle lever 203 swingably attached to the handle 202, a throttle lock lever 204 for locking the throttle lever 203, and a locking member 205 disposed to be pushed towards the machine body 201 into abutment on the machine body 201 by the swing movement of the throttle lever 203, thereby stopping rotation of the handle 202.
The throttle lock lever 204 is released from the throttle lever 203 by moving as indicated by an arrow c1. The throttle lever 203 is then gripped to move as indicated by an arrow c2, thereby pushing the locking member 205 out as indicated by an arrow c3 so as to lock the handle 202 to the machine body 201.
As for the power working machine 200, however, it is troublesome to rotate and lock the handle 202 because, in order that the handle 202 rotated relative to the machine body 201 through a predetermined angle is locked to the machine body 201, the throttle lock lever 204 is released from the throttle lever 203 and thereafter the throttle lever 203 is gripped to press the locking member 205 towards the machine body 201.
As for the power working machine 200, moreover, it is impossible to perform the following two operations simultaneously: (1) locking the handle 202 to prevent the rotation of the handle 202; and (2) releasing the throttle lock lever 204 from the throttle lever 203. Thus, the power working machine 200 presents a problem that such a connection component as a centrifugal clutch would provide such a timing of operation as to drive cutting blades (not shown) before the handle 202 is locked to the machine body 201.
There is a demand for a power working machine including a handle rotatable through a simple operation and taking such measures against erroneous operation of a throttle lever as to, for example, prevent operation of the throttle lever during rotational operation of the handle and to prevent the rotational operation of the handle during the operation of the throttle lever.
USPTO Backgrounds
USPTO Backgrounds