The present invention relates to a hand shovel and more particularly to an improved digging shovel with a rotatable handgrip.
A typical hand shovel used for digging comprises a blade to which an elongated handle is fixed. The handle includes a shaft and a handgrip. The handgrip is typically D-shaped and is fixed to the proximal end of the shaft. In use, a person will grip the handgrip with its left hand and must grasp a distal portion of the shaft with its right hand (if the person is right handed). The shovel is used to dig or scoop material and to transfer it to an adjacent location causing the user to twist its left hand wrist, forearm, elbow, upper arm and shoulder to accommodate the angle of the shovel while the right arm merely supports the shaft at a distal portion thereof. The movement is repetitive and will have negative implications on the left arm and hand. For instance the prehension and strength of the left-hand arm is reduced by 25%. The muscles and tendons of the wrist, lower arm, elbow, upper arm and shoulder are under stress thus creating fatigue, reducing performance and increasing the probability of injuries in the long-term.
Conditions such as carpal tunnel syndrome are common to construction workers whose hands, wrists and arms become tired, stiff, inflamed and swollen due to continued use of the shovel at different angles. The carpal tunnel in the wrist is an unyielding and non-expanding fibre and bone tunnel through which flexor tendons and the median nerve extend to the hand. The flexor tendons are contracted and extended by muscles of the forearm and hand which flex and extend the fingers. So long as the flexor tendons have room to move, they contract and extend easily. If the carpal tunnel is bent in any direction or if any of the flexor tendons become inflamed for any reason, the flexor tendons will not move easily and will create more friction against the tunnel and the median nerve resulting in painful inflammation and swelling within the tunnel area. Furthermore, because of the swelling, the median nerve can become compressed, pinched or bent which can lead to tendinitis or other cumulative trauma disorders.
According to the present invention, there is provided a shovel comprising a handle and a blade fixed to the handle at the distal end thereof. The handle includes an elongated shaft and a handgrip located at the proximal end thereof. The handle defines a longitudinal axis and the handgrip is rotatably mounted to the proximal end of the shaft for rotation about the longitudinal axis.
The advantage of this improved shovel is evident from the fact that, in the case of a right-handed person, the right hand grasping the distal end of the shaft can rotate the shovel about the longitudinal axis while the left-hand which grasps the handgrip will remain relaxed and stress-free.
Reference will now be made to the accompanying drawings, showing by way of illustration a particular embodiment of the present invention and in which:
a is fragmentary front view of another embodiment of the invention;
b is a fragmentary longitudinal cross-section along lines 5b-5b of
The shovel 1 shown in
The handle 3 includes a shaft 3a and a handgrip 2. The shaft 3a is connected to the blade 4 at a distal end 3b. The handgrip 2 is rotatably connected to the shaft 3 as will be described further. The handgrip 2 includes a bight 2c extending between the arms of a yoke 2a. The yoke 2a is fixed to a sleeve 2b which is rotatably mounted to the shaft 3a.
The blade 4 is made out of metal preferably steel and includes a sleeve 4a which receives the shaft distal end 3b of the handle 3, and a pan 4b. The distal end 3b is boiled into the sleeve 4a. The pan 4b may be in the form of a conventional pointed digging pan or a rectangular mud or snow pan. In the present embodiment the pointed digging pan includes flat facets which are meant to provide increased strength to the pan 4b. Since the digging pan 4b shown in
In the preferred embodiment as shown in
A cuff 9 may be provided over the shaft 3a at the joint form between the sleeve 2b and the shaft 3a in order to avoid the accumulation of dirt in the joint.
Referring now to
The dotted lines in