1. Field of Invention
The invention relates to a hand puller and, in particular to a hand puller with an improved structure of double stopping plates.
2. Related Art
As shown in the structure, the puller has only one stopping plate 85. The stopping plate 85 may not accurately engage with the ratchet 83 because there is some variation in the tooth span. When the puller is tightened, the stopping plate 85 may depart from the ratchet so that the strap falls off.
However, the stopping walls on both sides of the fixing part 90 have to be higher so that the two stopping plates 91 can be installed on the same side of the ratchet 92. The structure of the fixing part 90 is thus larger than the fixing part with one stopping plate. This increases the cost of the hand puller. Besides, when the hand puller relaxes the strap, one sometimes has to do it slowly. During the slow strap release of the hand puller with two stopping plates 91, the user has to pull the pulling part 93 so that the two stopping plates 91 back their teeth one by one. Without appropriate control, the strap may be released too much.
Therefore, it is an objective of the invention to solve the problems in the conventional hand puller.
An objective of the invention is to provide a hand puller with a structure of double stopping plates to achieve the effect of engaging and stopping its ratchet with the two stopping plates when the hand puller holds its strap.
Another objective of the invention is to provide a slow strap release mechanism at the fixing part so that the driving claw of the pulling part can shift in the stroke and the ratchet can back the strap out tooth by tooth.
To achieve the above objectives, the invention has an axle part between a fixing part and a pulling part. Both ends of the axle part have a ratchet. The fixing part has a stopping plate. The pulling part has a driving claw. The stopping plates and the driving claw engage with the teeth of the ratchets, respectively.
Moreover, the fixing part has a stopping plate on the opposite sides of the axle part. When the driving claw rotates the ratchet, the stopping plate on one side of the ratchet engages the bottom part of the teeth of the ratchet. The stopping plate on the opposite side of the ratchet urges against the top part of the teeth the ratchet. The two stopping plates thus move reciprocally between the top and bottom parts of the teeth.
At the pivotal axle part, the fixing part has a guiding section for the driving claw to urge while pulling. The guiding section has a stopping wall for the driving claw to urge at the end of the stroke. A positioning groove is formed above the stopping wall. A sliding groove is formed between the positioning groove and the guiding section.
The driving claw drives the ratchet to rate during the stoke of the guiding section and urges against the stopping wall when it is fully pulled. When the driving claw is pulled up to the positioning groove and disposed therein, it completely departs from the ratchet. Two protruding parts are disposed corresponding to the two stopping plates at the axle part of the pulling part. When the driving claw moves back and forth in the sliding groove, the two protruding parts push away the corresponding stopping plates. The teeth of the ratchet thus back out the strap tooth by tooth.
The invention will become more fully understood from the detailed description given herein below illustration only, and thus is not limitative of the present invention, and wherein:
The present invention will be apparent from the following detailed description, which proceeds with reference to the accompanying drawings, wherein the same references relate to the same elements.
Please refer to
This embodiment provides an improved hand puller. An axle part 3 goes through a fixing part I and a pulling part 2. Both ends of the axle part 3 are provided with a ratchet 4, respectively. The fixing part 1 has stopping plates I1. The pulling part 2 has a driving claw 21. The stopping plate 11 and the driving claw 21 engage with the teeth 41 of the ratchet 4. As shown in
The fixing part 1 has a stopping plate 11 ob opposite ends of the axle 3, respectively. When the driving claw 21 drives the ratchet 4, the stopping plate 11 on one side of the ratchet 4 engages with the bottom part 41a of the teeth 41 of the ratchet 4. The stopping plate 11 on the opposite side of the ratchet 4 urges against the top part 41b of the teeth 41 of the ratchet 4. The two stopping plates 11 alternately perform a reciprocal motion between the bottom part 41a and the top part 41b of the teeth 41.
As shown in
According to the above-mentioned stricture (also shown in
As shown in
From the above description, it is easy to see that one advantage of the invention is in that two opposite sides of the ratchet of the fixing part 1 have a stopping plate, respectively. When the pulling part 2 is pulled, even if the teeth 41 on the ratchet have some variation in their span, the cooperation of the two stopping plates 11 still enable them to engage with the ratchet 4, preventing the strap from falling off. It is not necessary to increase the height of the structure on both sides of the fixing part to accommodate the tho stopping plates 11 as in the prior art. The component cost is thus lower. Moreover, to prevent cargo from shifting to one side and even toppling over because a single set of hand puller impose a tightening force only in one direction, the fixing part I of the invention can involve two sets of hand pullers connected via two sets of through holes 16. Therefore, the user can use the same pulling part 2 to drive two fixing parts 1, exerting a more uniform force.
Of course, the invention has many other embodiments that only vary in details. Please refer to
Although the invention has been described with reference to specific embodiments, this description is not meant to be construed in a limiting sense. Various modifications of the disclosed embodiments, as well as alternative embodiments, will be apparent to people skilled in the art. Therefore, it is contemplated that the appended claims will cover all modifications that fall within the true scope of the invention.