US20110061213A1

US20110061213A1 - Hand puller with a structure of double stopping plates

Info

Publication number: US20110061213A1
Application number: US12/558,710
Authority: US
Inventors: Wen-Cheng Chang
Original assignee: Win Chance Metal Co Ltd
Current assignee: Win Chance Metal Co Ltd
Priority date: 2009-09-14
Filing date: 2009-09-14
Publication date: 2011-03-17

Abstract

A hand puller with the structure of double stopping plates is disclosed. An axle part goes through a fixing part and a pulling part. Both ends of the axle part have a ratchet, respectively. The fixing part has two stopping plates, fixed to the two opposite sides of the axle part. The pulling part has a driving claw. The driving claw and the stopping plates of the fixing part engage with the ratchet.

Description

BACKGROUND OF THE INVENTION

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
FIG. 11 shows a conventional hand puller. Its fixing part 80 and pulling part 81 are joined with an axle part 82. The axle part 82 has a ratchet 83. The fixing part 80 has a stopping plate 85. The pulling part 81 has a driving claw 86. The stopping plate 85 and the driving claw 86 engage with the ratchet 83.
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.
FIG. 12 shows another conventional hand puller. The fixing part 90 has two stopping plates 91 installed on the same side of the ratchet 92. They engage with the ratchet 92 from top and bottom, respectively, to achieve strap tightening.
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.

SUMMARY OF THE INVENTION

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.

BRIEF DESCRIPTION OF THE DRAWINGS

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:

FIG. 1 is a three-dimensional view of the invention;

FIG. 2 is a three-dimensional exploded view of the invention;

FIG. 3 is a side view of the structure of the invention;

FIG. 4 is a schematic view of the pulling part being pulled up according to the invention;

FIG. 5 is a schematic view of the disclosed driving claw at the front end of the sliding groove;

FIG. 6 is a schematic view of the disclosed driving claw at the back end of the sliding groove;

FIG. 7 is a schematic view of the driving claw in the positioning groove;

FIG. 8 is a schematic view of the relative position of the disclosed two hand puller before they are combined;

FIG. 9 is a schematic view of the assembled two hand puller according to the invention;

FIG. 10 is a three-dimensional view of a second embodiment of the invention;

FIG. 11 is a schematic view of a conventional hand puller; and

FIG. 12 is a schematic view of another conventional hand puller.

DETAILED DESCRIPTION OF THE INVENTION

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 FIGS. 1 to 7 for an embodiment of the invention. It is used only for the illustration purpose. The invention is not restricted to such a structure.
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 FIG. 2, the pulling part 2 can depart from the fixing part 1.
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 41 b of the teeth 41 of the ratchet 4. The two stopping plates 11 alternately perform a reciprocal motion between the bottom part 41 a and the top part 41 b of the teeth 41.
As shown in FIGS. 3 to 7, the fixing part I has a guiding section 12 at the pivotal axle part 3 for the end of the driving claw 21 to urge against when it is pulled. The guiding section has a stopping wall 13 for the sidewall of the driving claw 21 to urge and stop at the end of its stroke. A positioning groove 14 is formed on the upper portion of the stopping wall 13. A sliding groove 15 is formed between the positioning groove 14 and the guiding section 12.
According to the above-mentioned stricture (also shown in FIGS. 3 and 4), the driving claw 21 drives the ratchet 4 during the stroke of the guiding section 12. It urges against the stopping wall 13 when fully pulled. The pulling part 2 is provided with two protruding parts 22 at the axle part 3 corresponding to the two stopping plates 1 1. As shown in FIGS. 5 and 6, as the driving claw 21 moves back and forth in the sliding groove 15, the two protruding parts 22 push away the corresponding stopping plates 11, respectively. The teeth 41 of the ratchet 4 thus back out the strap tooth by tooth. As shown in FIG. 7, the driving claw 21 completely depart from the ratchet 41 when it is pulled and inserted into the positioning groove 14.
As shown in FIGS. 8 and 9, the fixing part 1 in this embodiment has two sets of through holes 16 in the back. The two sets of through holes 16 are in communication when the fixing parts 1 of two hand pullers are connected. Two sets of locking elements 17 go through and connect them in this case.
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 FIG. 10 for a second embodiment of the invention. The fixing part 1A are fixed to the pulling part 2A. That is, the fixing part 1A and the pulling part 2A cannot be separated. However, such a fixed-type hand puller still has the above-mentioned two stopping plates 11A and achieves the slow strap backing effect.
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.

Claims

What is claimed is:

1. A hand puller having the structure of double stopping plates, comprising:

a fixing part having stopping plates;

a pulling part having a driving claw;

an axle part going through the fixing part and the pulling part, with a ratchet on each of its two ends;

wherein the stopping plates are disposed on the two opposite sides of the axle part, respectively; when the driving claw rotates the ratchet, the stopping plate on one side of the ratchet engages with the bottom part of a tooth of the ratchet and the stopping plate on the opposite side urges against the top part of the tooth of the ratchet; the two stopping plates perform a reciprocal motion between the bottom part and the top part of the teeth; the fixing part has a guiding section at the axle part for the end of the driving claw to urge against; the guiding section has a stopping wall at the end of its stroke for the driving claw to urge and stop; a positioning groove is formed in the upper portion of the stopping wall; and a sliding groove is formed between the positioning groove and the guiding section; the driving claw rotates the ratchet during the stroke of the guiding section and urges against the stopping wall when fully pulled; the driving claw departs from the ratchet when it is pulled up and disposed into the positioning groove; two protruding parts are formed corresponding to the two stopping plates on the pulling part at the joint to the axle part; and when the driving claw moves back and forth in the sliding groove, the two protruding parts push away the corresponding stopping plates so that the teeth of the ratchet back out the strap tooth by tooth.

2. The hand puller having the structure of double stopping plates as in claim 1, wherein the fixing part has two sets of through holes in the back that are in communication when the two fixing parts of two hand pullers are connected, and two sets of locking elements go through the through holes to join the hand pullers.

3. The hand puller having the structure of double stopping plates as in claim 1, wherein the fixing part and the pulling part are connected in a fixed way.