Patent Application
20170144276
1. Fields of the Invention
The present invention relates to a ratchet wrench, and more particularly, to a ratchet wrench which is manufactured at low cost and has sufficient strength.
2. Descriptions of Related Art
The conventional ratchet wrench known to applicant is disclosed in
However, as shown in
U.S. Pat. No. 6,382,051 discloses another ratchet wheel whose recess includes a closed top and a closed bottom, so that it has the similar shortcomings.
The present invention intends to provide a ratchet wrench which is easily manufactured so as to eliminate the shortcomings mentioned above.
The present invention relates to a ratchet wrench and comprises a body, a ratchet wheel, a pawl, a ring, a top clip and a bottom clip. The body includes a through hole which is defined through the top and the bottom of the body. The body includes top recessed area and a bottom recessed area respectively defined in the top and the bottom thereof. A recess is defined in the inner periphery of the through hole and a protrusion extends from one end of the recess. A receiving slot is defined in the protrusion. A resilient member is received in the receiving slot so as to bias the pawl in the recess to be engaged with the ratchet wheel. The ring is engaged with the top recessed area to cover the through hole the recess. The top clip is engaged with the top recessed area and presses the ring, and clips the ratchet wheel. The bottom clip is engaged with the bottom recessed area and clips the ratchet wheel.
The primary object of the present invention is to provide a ratchet wrench wherein the recess, the receiving slot and the through hole all have an open top which allows the manufacturers to easily make the through hole, the receiving slot and the recess.
The present invention will become more apparent from the following description when taken in connection with the accompanying drawings which show, for purposes of illustration only, a preferred embodiment in accordance with the present invention.
Referring to
A ratchet wheel 20 is rotatably received in the through hole 11 and includes a ratchet portion 21 defined in the outer periphery thereof. A connection portion 22 is formed to the ratchet wheel 20, wherein the connection portion 22 is a polygonal hole in this embodiment. A first pivotal portion 23 and a second pivotal portion 25 are respectively formed on two ends of the ratchet wheel 20. The first pivotal portion 23 has a top groove 24, and the second pivotal portion 25 has a bottom groove 26. The second pivotal portion 25 is pivotably engaged with the through hole 11 and the bottom recessed area 17.
A pawl 30 is movably received in the recess 12 and has a toothed face 31 defined in the front side thereof, and the toothed face 31 is engaged with the ratchet portion 21 of the ratchet wheel 20. The pawl 30 has a positioning portion 32 defined in the first end thereof, and the positioning portion 32 faces the entrance 141. The pawl 30 has a contact end 33 defined the second end thereof, and the contact end 33 contacts the inner periphery of the recess 12. A first angle 121 is defined between the inner end of the first recess 12 and the inner periphery of the first recess 12. The first angle 121 is between 90 to 120 or 100 degrees. A second angle is defined between the contact end 33 and a rear side of the pawl 30 that faces the inner end of the first recess 12. The second angle is matched with the first angle 121.
A resilient member 40 is received in the recess 12 and biased between the inner end of the receiving slot 14 and the positioning portion 32 to engage the toothed face 31 of the pawl 30 engaged with the ratchet portion 21 of the ratchet wheel 20.
A ring 50 is received in the top recessed area 15 and contacts the first shoulder 16 and the top of the protrusion 13. The ring 50 has an inner periphery 51 thereof mounted to the first pivotal portion 23. The ring 50 further includes a lid 52 extending therefrom, so that the ring 50 is shaped to cover the recess 12 and the top recessed area 15 to cover up the pawl 30 and the resilient member 40.
A top clip 60 is engaged with the top recessed area 15 and the top groove 24, and contacts the ring 50 to restrict the ring 50 from separating from the ratchet wheel 20. A bottom clip 70 is engaged with the bottom recessed area 17 and the bottom groove 26, and contacts the second shoulder 18 formed on the bottom of the bottom recessed area 17 and positioned between the bottom recessed area 17 and the through hole 11. The ratchet wheel 20 is restricted within the through hole 11 by the ring 50, the top clip 60 and the bottom clip 70.
As shown in
A first curved angle 195 is defined between the first bottom recessed area 170 and the second shoulder 18. A second curved angle 196 is defined between the first through hole 110 and the first bottom recessed area 170. The first protrusion 130 has a third curved angle 197 formed along edges thereof. A fourth curved angle 198 is formed at the lower edge of the first recess 120.
As shown in
The second-stage body 101 removed from the fine forging mold set is then put in a final mold set and treated by a punching machine to remove the four angles 191, 192, 193, 194, and to remove the first, second and fourth curved angles 195, 196, 198 to complete the formation of the through hole 11, the recess 12, the protrusion 13, the receiving slot 14, the top recessed area 15 and the bottom recessed area 17. The final product is the body 10 as disclosed in
The method for making the ratchet wrench includes the following steps:
step 1: preparing material according to the design of the body 10;
step 2: forging the material for the body 10 in a rough forging mold, and the material is formed to have the through hole 11, the recess 12, the protrusion 13 and the bottom recessed area 17;
step 3: the body 10 removed from the rough forging mold set and put in a fine forging mold set to be treated to form the through hole 11, the recess 12, the protrusion 13 and the bottom recessed area 17 in detailed specifications;
step 4: the body 10 removed from the fine forging mold set and the edges are cut under certain temperature;
step 5: the body 10 put in a final mold set and treated by a punching machine to make the through hole 11 through the body 10, so that the through hole 11, the recess 12, the protrusion 13, the receiving slot 14, the top recessed area 15 and the bottom recessed area 17 are completely formed as shown in
step 6: the body 10 being treated by the process of annealing, the temperature of the body after going through the process of annealing is 18-25 degrees Celsius;
step 7: the body 10 being treated by the process of sand blasting to remove defects of oxidation from the surface of the body 10;
step 8: the body 10 being polished to reduce the roughness of the surface of the body 10;
step 9: grinding the body 10 to make the thickness of the body 10 meet the tolerance requirement of design;
step 10: the body 10 being treated by heat treatment to change the microstructure of the surface and interior of the body 10;
step 11: the body being treated by vibration grinding to further polish the surface of the body 10;
step 12: the body 10 being electro-coated to increase the features of anti-corrosion and durability, and to have an aesthetic outer appearance; and
step 13: the ratchet wheel 20, the pawl 30, the resilient member 40, the ring 50, the top clip 60 and the bottom clip 70 being installed to the body 10.
In another embodiment, the connection portion 22 can be a rectangular protrusion.
The advantages of the present invention are that the recess 12 and the receiving slot 14 are opened to the top of the body 10 so that they are easily manufactured.
The through hole 11 is defined through the body 10 so that the feeding of the tool making the through hole 11 does not need to be carefully controlled.
The through hole 11, the recess 12 and the receiving slot 14 are able to be made by the same one drilling tool.
The through hole 11, the recess 12 and the receiving slot 14 are able to be completed in the same machine.
The through hole 11, the recess 12 and the receiving slot 14 are opened to the top of the body 10, so that they can be done by one time of punching after being forged.
The body 10 can be manufactured by either drilling or punching, the options are plenty.
The receiving slot 14 needs not to be made by any extra process so as to save manufacturing cost.
As shown in
The first pivotal portion 23 and the second pivotal portion 25 are respectively connected to the inner periphery of the ring 50 and the through hole 11 so that the ratchet wheel 20 is stably installed.
When removing either one of the top clip 60 or the bottom clip 70, the ratchet wheel 20 is conveniently removed from the through hole 11 to replace parts in the body 10.
While we have shown and described the embodiment in accordance with the present invention, it should be clear to those skilled in the art that further embodiments may be made without departing from the scope of the present invention.
