The present invention relates to a ratchet wrench, which is used to rotate a screw or a nut or a similar object.
In the prior art, patents such as U.S. Pat. No. 2,188,846, U.S. Pat. No. 2,201,827, U.S. Pat. No. 7,237,460, CA2356549, U.S. Pat. No. 6,282,992B1, and US2004139823, U.S. Pat. No. 7,237,460B2 and EP1215014A2 have put forward various conventional art of a ratchet wrench. The conventional art in the early period has advantages, but still needs continuous improvement.
The present invention substantially provides:
Other embodiments of the present invention and detailed advantageous features can be appreciated from the following Brief description of the drawings and Detailed Description.
As shown in
The body (10) comprises an operating part (14). The operating part (14) comprises a groove (16) formed of a bottom wall (18), and an inner peripheral wall (20) surrounding the bottom wall (18). A front end of the groove (16) can accommodate the ratchet (40), the first pawl (60) and the second pawl (80) therein. A first wall (22) and a second wall (24) are disposed or formed in the groove (16). The first pawl (60) is disposed between the first wall (22) and the ratchet (40), and the second pawl (80) is disposed between the second wall (24) and the ratchet (40). The first wall (22) is configured so that when the first pawl (60) is moved to a first position thereof, for example, due to an elastic force between the first pawl (60) and the inner peripheral wall (20), the first pawl (60) is caught or engaged between the first wall (22) and the ratchet (40), and therefore engaged with the ratchet (40) for transmitting a torque. The second wall (24) is configured so that when the second pawl (80) is moved to a first position thereof, for example, due to an elastic force between the second pawl (80) and the inner peripheral wall (20), the second pawl (80) is caught or engaged between the second wall (24) and the ratchet (40), and therefore engaged with the ratchet (40) for transmitting a torque. Therefore, when the first pawl or second pawl is at its respective first position, said first pawl or second pawl provides a force/torque to the ratchet (40) for driving or rotating a driven element coupled to the ratchet (40); when the first pawl or second pawl is at its respective second position, said first pawl or second pawl does not provide such force/torque to the ratchet (40).
A platform is disposed or formed at a rear end of the groove (16). The platform has a height raised from the bottom wall (18). The control member (100) may be fixed on the platform. One end of the platform is defined by the first wall (22) and the second wall (24). The platform is provided with a hole (H1), through which the control member (100) is pivotally fixed to the platform.
According to a preferred embodiment, the first wall (22) extends from a first end, close to the inner peripheral wall (20), to a second end, close to the second wall (24). The first wall (22) is inclined so that a distance between the second end and the ratchet (40) is shorter than a distance between the first end and the ratchet (40). The second wall (24) extends from a first end, close to the inner peripheral wall (20), to a second end, close to the first wall (22). The second wall (24) is inclined so that a distance between the second end and the ratchet (40) is shorter than a distance between the first end and the ratchet (40).
According to another preferred embodiment, the groove (16) comprises two accommodation chambers for accommodating the first pawl (60) and the second pawl (80), respectively. One accommodation chamber comprises the first wall (22), and the other accommodation chamber comprises the second wall (24). The first wall (22) and the second wall (24) each slope towards the inside to form an upward sloping surface (for example, a straight or curved upward sloping surface), and are inclined towards the front end of the groove (16).
The first pawl (60) is arranged between the first wall (22) of the body (10) and the ratchet (40), and may move between the first position and a second position relative to the ratchet. At the first position, the first pawl (60) is coupled with the ratchet (40) and is supported by the first wall (22) so that the body (10) provides the transmitted torque in a first rotation direction through the first pawl (60). At the second position, the first pawl (60) is separated from the ratchet (40) and does not transmit the torque.
The first pawl (60) comprises a side surface (or first side surface) arranged between the ratchet (40) and the first wall (22) and biased or pressed by a spring (S) so that the first pawl (60) and the second pawl (80) are normally coupled with the ratchet (40). According to an embodiment, one end of the spring (S) is connected to a fastening member (68, 88) firmly urged against the inner peripheral wall. Normally (i.e., in the condition when not controlled by the control member (100)), the first pawl (60), under the force applied by the spring (S), moves along a direction substantially parallel to the first wall (22) towards a tooth portion (42) of the ratchet (40).
The second pawl (80) is arranged between the second wall (24) of the body (10) and the ratchet (40), and may move between the first position and a second position relative to the ratchet. At the first position, the second pawl (80) is coupled with the ratchet (40) and is supported by the second wall (24) so that the body (10) provides the transmitted torque in a second rotation direction through the second pawl (80). At the second position, the second pawl (80) is separated from the ratchet (40) and does not transmit the torque.
The second pawl (80) comprises a side surface (or first side surface) arranged between the ratchet (40) and the second wall (24) and biased or pressed by a spring (S) so that the first pawl (60) and the second pawl (80) are normally coupled with the ratchet (40). According to an embodiment, one end of the spring (S) is connected to a fastening member (68, 88) firmly urged against the inner peripheral wall. The forces applied by the springs (S) are substantially parallel to the first wall (22) and the second wall (24), respectively. Normally (i.e., in the condition when not controlled by the control member (100)), the second pawl (80), under the force applied by the spring (S), moves along a direction substantially parallel to the second wall (24) towards the tooth portion (42) of the ratchet (40). Therefore, as the first pawl (60) and the second pawl (80), under the biased pressing by the spring (S), move further inwards, the teeth are engaged more tightly.
The first pawl (60) and the second pawl (80) are separated from each other by a spacing so that the two do not interfere with each other when moving.
End teeth (66, 86) of teeth (62, 82) of the first pawl (60) and the second pawl (80) each protrude from a side surface (64, 84) (or a second side surface (64, 84)) thereof. Therefore, end teeth (66, 86) can enlarge the contact surface between teeth (62, 82) and tooth portion (42) of ratchet (40) so as to help the first pawl (60) and the second pawl (80), when providing toque, apply force towards the first wall (22) and the second wall (24). Due to end teeth (66,86), a blunt notch is formed between end teeth (66, 86) and the second side surface (64, 84).
As shown in
When the control member (100) is in the first position, as shown in
During assembly, a fixing member (44) is used to enable the ratchet (40) to be pivotally fixed on the operating part. After all components are mounted in the groove (16), a cover plate (F), a C-shaped ring (C) and a ring (R) close an open end of the groove (16), and then the switch (120) is fixed onto the control member (100). Essentially, the switch (120) and the control member (100) are operatively connected so that it is not limited in the present invention that the control member (100) and the switch (120) are designed to be an integral component or different components.
Number | Date | Country | Kind |
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101107061 A | Mar 2012 | TW | national |
Number | Name | Date | Kind |
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2188846 | Rueb | Jan 1940 | A |
2201827 | Froeschl et al. | May 1940 | A |
6282992 | Hu | Sep 2001 | B1 |
6666112 | Hu | Dec 2003 | B2 |
7047842 | Lee | May 2006 | B1 |
7089830 | Hu | Aug 2006 | B2 |
7237460 | Hu | Jul 2007 | B2 |
20040055424 | Huang | Mar 2004 | A1 |
20040139823 | Hu | Jul 2004 | A1 |
20050257650 | Hu | Nov 2005 | A1 |
Number | Date | Country |
---|---|---|
2 356 549 | Jun 2002 | CA |
1 215 014 | Jun 2002 | EP |
343558 | Nov 2008 | TW |
434653 | Aug 2012 | TW |
Entry |
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Office Action from State Intellectual Property Office of People's Republic of China in corresponding Chinese application 201210053654.1 dated Sep. 23, 2014, 11 pp. |
Extended European Search Report and Search Opinion of European Patent Office in corresponding European application 12199697.9 dated Aug. 11, 2014, 7 pp. |
Number | Date | Country | |
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20130228048 A1 | Sep 2013 | US |