1. Field of the Invention
The present invention relates to a one-way ratchet wrench having a bevel groove with a specific angle to avoid the disengagement of an elastic element when the wrench is turned.
2. Description of the Prior Art
A conventional structure as disclosed in U.S. Pat. No. 6,807,882 has the shortcomings:
1. The control groove 13 of the wrench body 10 makes a notch in the appearance of the wrench. This results in poor visual aesthetics of the entire assembly.
2. When a drilling tool begins to drill the hole, it is easy to make the position of the drill hole deviated due to the lateral applied force from the arcuate surface. It is more difficult to provide a precise position of the control groove 13. The deviation in the position of the drill hole causes defectives to the wrench body 10.
3. If it is desired to drill a horizontal control groove 13 from the second receiving recess 15, the processing is more inconvenient.
4. It is less easy to assemble the elastic element 70 and the anchor 60 in the narrower second receiving recess 15.
Furthermore, the shortcomings of U.S. Pat. No. 5,979,274 are that the elastic restoring force of the bending elastic element 13 is weakened as well as the life is shorter.
Moreover, the shortcomings of U.S. Pat. No. 5,636,557 are that the structure itself of the control plate 15 is complicated and has more portions to be bending processed so it requires more labor and time in manufacture and it is substantially difficult to meet the manufacture benefit.
A one-way ratchet wrench according to the present invention includes a wrench body, a ratchet wheel, a pawl, an anchor, an elastic element and the following elements. A cover is hollow and annular and is annularly provided with a groove. The cover is mounted on the first receiving recess of the wrench body and presses against engaging teeth. A clip ring is mounted between the clip groove of the wrench body and the groove of the cover. The cover and the ratchet wheel are thereby mounted in the first receiving recess of the wrench body such that the cover and the ratchet wheel would not disengage from the first receiving recess of the wrench body during rotation.
As illustrated in
The acting end of the wrench body 10 is provided with a first receiving recess 11, a smaller-diameter pressing edge 111 is disposed on the bottom surface of the first receiving recess, one side of the first receiving recess is provided with a curved second receiving recess 12 which is communicated with the first receiving recess 11, the diameter of the second receiving recess 12 is smaller than that of the first receiving recess 11, the center of the curve of the second receiving recess 12 is located in the first receiving recess 11, the center of the circle of the first receiving recess 11 is at a distance from that of the second receiving recess 12, the top and bottom of the second receiving recess 12 are closed respectively, a bevel groove is disposed on the periphery on one side of the second receiving recess 12 of the wrench body 10, the bevel groove 13 is circular hole shaped but not through-going, and the longitudinal axis of the bevel groove 13 intersects the center of the circle of the first receiving recess 11 and has an included angle with respect to the axis of the wrench body 10 which is from ten to twenty-five degrees;
The ratchet wheel 20 is pivotally disposed in the first receiving recess 11 and provided with a sleeve portion 21, and engaging teeth 22 are circularly arranged around an outer periphery of the ratchet wheel 20 which presses against the pressing edge 111 of the wrench body 10;
One side of the pawl 30 is provided with pawl teeth 31 for engaging with the engaging teeth 22 of the ratchet wheel 20, one side of the pawl 30 presses against a wall of the second receiving recess 12 of the wrench body 10, and the other side of the pawl 30 is provided with a pressing surface 32;
The anchor 40 is received in the bevel groove 13 of the wrench body 10 and projects into the second receiving recess 12, the anchor 40 does not contact with the engaging teeth 22 of the ratchet wheel 20, and the axis of the anchor 40 intersects the center of the circle of the first receiving recess 11 and has an included angle with respect to the axis of the wrench body 10 which is the same as the included angle between the axis of the bevel groove 13 and the center of the circle of the first receiving recess 11; and
One end of the elastic element 50 presses against the pressing surface 32 of the pawl 30, the other end of the elastic element 50 presses against the anchor 40, the elastic force of the elastic element 50 allows the pawl teeth 31 of the pawl 30 to engage with the engaging teeth 22 of the ratchet wheel 20, the anchor 40 is received at a tilt angle in the bevel groove 13, the opening C, defined by the anchor 40 and the pawl 30, becomes smaller in width starting from the inner curved surface of the second receiving recess 12 to the engaging teeth 22 which resides in the first receiving recess 11, and the elastic element 50 is propped between the pawl 30 and the anchor 40 without disengagement such that the elastic element 50 is positioned within the second receiving recess 12.
A cover 60 is hollow and annular and is annularly provided with a groove 61. The cover 60 is mounted on the first receiving recess 11 of the wrench body 10 and presses against engaging teeth 22.
A clip ring 70 is mounted between the clip groove 14 of the wrench body 10 and the groove 61 of the cover 60. The cover 60 and the ratchet wheel 20 are thereby mounted in the first receiving recess 11 of the wrench body 10 such that the cover 60 and the ratchet wheel 20 would not disengage from the first receiving recess 11 of the wrench body 10 during rotation.
The assembled wrench is shown in
As illustrated in
When the wrench body 10 is turned to fasten a workpiece, the engaging teeth 22 of the ratchet wheel 20 engage with the pawl teeth 31 of the pawl 30, one side of the pawl 30 presses against a wall of the second receiving recess 12 of the wrench body 10, and the other side of the pawl 30 presses against the elastic element 50. Thus, the workpiece can be rotated when the ratchet wheel 20 is turned counterclockwise, and free rotation occurs when the ratchet wheel 20 is turned clockwise. The user can change the operation direction as long as the one-way ratchet wrench is turned over to the other side.
As illustrated in
As illustrated in
As illustrated in
The present invention has the advantages as below:
1. The closer to the first receiving recess 11 the opening C defined by the anchor 40 and the pawl 30 goes, the smaller the opening C is. The elastic element 50 is propped between the pawl 30 and the anchor 40 without disengagement such that the elastic element 50 is positioned within the second receiving recess 12 of the wrench body 10.
2. The appearance of the wrench remains intact, thereby providing improved visual aesthetics.
3. As illustrated in
4. The assembly of the wrench is made in an easy and convenient way and in less time.
Number | Name | Date | Kind |
---|---|---|---|
5636557 | Ma | Jun 1997 | A |
6446530 | Chang | Sep 2002 | B1 |
6539825 | Lin | Apr 2003 | B1 |
6779422 | Chen | Aug 2004 | B2 |
6807882 | Hu | Oct 2004 | B2 |
20030041697 | Hsien | Mar 2003 | A1 |
20040163498 | Liu | Aug 2004 | A1 |
20070101832 | Lee | May 2007 | A1 |