Ratchet wrench with dustproof structure

A ratchet wrench includes a driving device. A compartment extends through the driving device. A drive member is received in the compartment. A ledge is formed on an inner periphery of an end of the compartment. A pressing rod extends into the drive member via the end of the compartment. The pressing rod is movable relative to the drive member along a rotating axis between a first position and a second position to control engagement with or detachment from a tool. A dustproof ring is mounted between the ledge and the pressing rod. The dustproof ring includes an outer side pressing against an abutment portion of the ledge and an inner side-pressing against the pressing rod wherever the pressing rod is in the first position and the second position.

BACKGROUND OF THE INVENTION

The present invention relates to a ratchet wrench with a dustproof structure and, more particularly, to a ratchet wrench including a dustproof ring mounted between a head and a pressing rod for providing a dustproof effect.

U.S. Pat. No. 7,311,019 discloses a ratchet wrench including a head and a handle connected to the head. The head includes top and bottom ends, with a through cavity formed in the head from the top end to the bottom end. A ratchet gear is disposed in the through cavity. A cover plate is mounted to the bottom end of the head, and a ledge is formed on the top end of the head, preventing the ratchet gear from disengaging from the head. The ratchet gear includes a hole receiving a pressing rod operable to control engagement with or disengagement from a socket or the like. An O-ring is mounted between the top end of the head and the ratchet gear, and another O-ring is mounted between the bottom end of the head and the ratchet gear, preventing or reducing ingress of dirt into a space between the head and the ratchet gear.

However, dirt can enter a gap between the pressing rod and the ratchet gear, impeding movement of the pressing rod relative to the ratchet gear. Thus, the pressing rod cannot be operated to control engagement/disengagement of the socket after an amount of dirt is accumulated in the gap between the pressing rod and the ratchet gear, damaging the ratchet wrench.

Thus, a need exists for a ratchet wrench with a novel dustproof structure preventing ingress of dirt into the gap between the pressing rod and the ratchet gear.

BRIEF SUMMARY OF THE INVENTION

The present invention solves this need and other problems in the field of dustproof ratchet wrenches by providing a ratchet wrench including a driving device having first and second sides spaced along a rotating axis. A compartment extends from the first side through the second side. The driving device further includes a drive member received in the compartment and rotatable about the rotating axis. The drive member includes an end, with the end of the drive member adapted to drive a tool. A ledge is formed on an inner periphery of an end of the compartment at the second side. The ledge includes an abutment portion. A pressing rod extends into the drive member via the end of the compartment at the second side. The pressing rod is movable relative to the drive member along the rotating axis to control engagement with or detachment from the tool. A dustproof ring is mounted between the ledge and the pressing rod. The dustproof ring includes an outer side and an inner side surrounded by the outer side and spaced from the outer side in a radial direction perpendicular to the rotating axis. The outer side presses against the abutment portion of the ledge. The inner side presses against the pressing rod.

In preferred forms, the outer side includes an outer periphery pressing against the abutment portion of the ledge. The inner side includes an inner periphery spaced from the outer periphery in the radial direction perpendicular to the rotating axis. The inner periphery includes a lip having an outer surface pressing against the pressing rod. The dustproof ring further includes a flange having an outer diameter perpendicular to the rotating axis. The abutment portion of the ledge is an annular face surrounding the rotating axis and having an inner diameter perpendicular to the rotating axis. The inner diameter of the abutment portion is smaller than the outer diameter of the flange, preventing the dustproof ring from disengaging from the drive member by moving the dustproof ring away from the first side along the rotating axis.

The lip extends from the inner periphery towards the second side. The lip further has an inner surface located between the outer surface and the inner periphery. A receiving space is defined between the inner periphery and the inner surface of the lip. The receiving space is adapted to receive dirt stopped by the dustproof ring.

Where used in the various figures of the drawings, the same numerals designate the same or similar parts. Furthermore, when the terms “first”, “second”, “inner”, “outer”, “side”, “end”, “portion”, “section”, “axial”, “radial”, “annular”, “clockwise”, “counterclockwise”, and similar terms are used herein, it should be understood that these terms have reference only to the structure shown in the drawings as it would appear to a person viewing the drawings and are utilized only to facilitate describing the invention.

DETAILED DESCRIPTION OF THE INVENTION

FIGS. 1-3are a perspective view, an exploded view, and a cross sectional view of a ratchet wrench with a dustproof structure according to the present invention, respectively. Ratchet wrench10includes a driving device20, a pressing rod30, and a dustproof ring40.

Driving device20includes a head21including first and second sides211and212spaced along a rotating axis L. Head21further includes a compartment213extending from first side211through second side212. Compartment213is circular in cross section. A drive member22is received in compartment213and rotatable about rotating axis L. An end of drive member22is adapted to drive a tool, such as a socket. Compartment213includes a first face abutting with a second face of drive member22opposite to the end of the drive member22. Second side212is axially spaced from the first face of compartment213opposite to the end of drive member22. Drive member22includes an annular protrusion extending axially from the second face and opposite to the end of drive member22past the first face. A ledge214is formed on an inner periphery of an end of compartment213at second side212. Ledge214includes an abutment portion217in the form shown as an annular face surrounding a rotating axis L. Abutment portion217of ledge214has a first diameter D1perpendicular to rotating axis L. Driving device20can be manually operated to rotate about rotating axis L. A handle can be removably attached to or integrally formed with head21.

A control groove215is formed in second side212of head21. Head21further includes a pawl groove216in communication with compartment213and control groove215. Pawl groove216is crescent in cross section. A pawl232is slideably received in pawl groove216. A control member231is pivotably received in control groove215. At least one elastic member233and at least one pressing member234are mounted between control member231and pawl232. Control member231is operable to move pawl232, controlling an engagement relation between drive member22and pawl232through the at least one elastic member233and the at least one pressing member234. Thus, head21can selectively drive the drive member22to rotate in either of a clockwise direction and a counterclockwise direction. In this embodiment, two elastic members233and two pressing members234are provided to assure reliable engagement between pawl232and drive member22.

A retaining ring24is mounted between head21and drive member22and located at the other end of compartment213adjacent to first side211. Retaining ring24abuts head21and drive member22, preventing drive member22from disengaging from head21via first side211.

Pressing rod30extends into drive member22via the end of compartment213at second side212. Pressing rod30is movable relative to drive member22along rotating axis L between a first position and a second position to control engagement with or detachment from the tool. As shown inFIG. 3, pressing rod30is arranged in the first position, and as shown inFIG. 6, pressing rod30is arranged in the second position. A head end of pressing rod30received in ledge214has a second diameter D2perpendicular to rotating axis L. Moreover, the head end of pressing rod30has a first height H1parallel to rotating axis L.

Dustproof ring40is made of an elastomeric material and mounted between ledge214and pressing rod30. Dustproof ring40presses against abutment portion217and pressing rod30, preventing dirt, sand, or other alien objects from entering an interior of head21via the end of compartment213at second side212. Thus, driving device20can operate smoothly even in a dirty environment. Moreover, dustproof ring40has a second height H2parallel to rotating axis L and greater than half of first height H1. A spring31is mounted between pressing rod30and drive member22. Specifically, spring31is mounted around pressing rod30. A ball32is mounted to the other end of pressing rod30adjacent to first side211. Ball32is located between pressing rod30and drive member22. A user can press pressing rod30to control movement of ball32between the first position and the second position, controlling engagement with or detachment from the tool. Spring31provides pressing rod30with a returning function and biases pressing rod30from the second position to the first position in which drive member22is engaged with the tool.

FIG. 4is a cross sectional view of dustproof ring40in an uncompressed state. Dustproof ring40in the uncompressed state is annular and rectangular in cross section. Dustproof ring40includes an outer side401and an inner side402surrounded by outer side401and spaced from outer side401in a radial direction perpendicular to rotating axis L, with outer side401pressing against abutment portion217of ledge214, with inner side402pressing against pressing rod30. More specifically, outer side401includes an outer periphery41pressing against abutment portion217of ledge214. Outer periphery41of dustproof ring40in the uncompressed state has a third diameter D3perpendicular to rotating axis L. Inner side402includes an inner periphery42spaced from outer periphery41in the radial direction perpendicular to rotating axis L. Inner periphery42is adjacent to pressing rod30. Inner periphery42of dustproof ring40in the uncompressed state has a fourth diameter D4perpendicular to rotating axis L.

Furthermore, a lip43extends from inner periphery42towards second side212. Lip43includes an outer surface432pressing against pressing rod30. Lip43further includes an inner surface431located between outer surface432and inner periphery42. Lip43further includes a tip433between inner and outer surfaces431and432. Tip433is annular and has a fifth diameter D5perpendicular to rotating axis L. A receiving space45is defined between inner periphery42and inner surface431of lip43. Receiving space45is adapted to receive dirt stopped by dustproof ring40.

Third diameter D3is larger than first diameter D1, such that dustproof ring40is in tight coupling with abutment portion217of ledge214. Fourth diameter D4is larger than second diameter D2, such that pressing rod30can move smoothly relative to drive member22along rotating axis L between the first position and the second position. Fifth diameter D5is smaller than second diameter D2, such that lip43of dustproof ring40is in tight coupling with an outer periphery of head end of pressing rod30, preventing dirt from entering an interior of driving device20from between pressing rod30and dustproof ring40.

Dustproof ring40further includes a flange44having a sixth diameter D6perpendicular to rotating axis L. Sixth diameter D6is larger than third diameter D3, such that flange44abuts against and is stopped by ledge214when dustproof ring40is moved away from first side211along rotating axis L, preventing dustproof ring40from disengaging from drive member22by moving dustproof ring40away from first side211along rotating axis L.

FIG. 5shows an enlarged view of a circled portion ofFIG. 3. Dustproof ring40made of elastomeric material is in tight coupling with abutment portion217of ledge214. Furthermore, lip43deforms while in tight coupling with the outer periphery of the head end of pressing rod30. Specifically, lip43bends towards outer side401, and outer surface432presses against the outer periphery of the head end of pressing rod30, providing an enhanced dustproof effect. When dirt is adhered to pressing rod30or enters a gap between pressing rod30and inner periphery42, inner surface431of lip43scrapes dirt adhered to the outer periphery of the head end of pressing rod30. The dirt falls into and is retained in receiving space45, preventing dirt from entering the interior of ratchet wrench10. Thus, driving device20can operate smoothly by preventing dirt from entering the gap between head21and drive member22. Furthermore, dirt is also prevented from entering the gap between the outer periphery of the head end of pressing rod30and drive member22, allowing the user to easily mount the tool to drive member22.

FIGS. 6 and 7show the pressing rod30in the second position. Pressing rod30is moved relative to drive member22along rotating axis L from the first position to the second position, when the user presses a top of the head end of pressing rod30. At this point, ball32is completely sunk into drive member22, enabling the tool adapted to be detached from drive member22. Moreover, outer surface432of lip43still presses against the outer periphery of the head end of pressing rod30, providing an enhanced dustproof effect. Furthermore, dirt is also prevented from entering the gap between the outer periphery of the head end of pressing rod30and drive member22, allowing the user to easily detach the tool from drive member22.

In conclusion, ratchet wrench10according to the present invention provides the following advantages:

1. Dustproof ring40mounted between driving device20and the outer periphery of the head end of pressing rod30prevents dirt from entering the gap between head21and drive member22whether pressing rod30is in the first position or in the second position, assuring smooth operation of driving device20. Furthermore, dirt cannot enter the gap between the outer periphery of the head end of pressing rod30and drive member22, allowing the user to easily mount the tool to or detach the tool from the drive member22.

2. Dustproof ring40made of elastomeric material deforms to an extent responsive to external conditions, such that dustproof ring40can be in tight coupling with abutment portion217of ledge214. Furthermore, lip43deforms while in tight coupling with the outer periphery of the head end of pressing rod30. Lip43bends towards outer side401, and outer surface432presses against the outer periphery of the head end of pressing rod30whether pressing rod30is in the first position or in the second position, providing enhanced dustproof effect. Inner surface431of lip43scrapes dirt adhered to the outer periphery of the head end of pressing rod30or entering the gap between the outer periphery of the head end of pressing rod30and inner periphery42, preventing dirt from entering the interior of ratchet wrench10.

3. Dustproof ring40provides receiving space45. The dirt falls into receiving space45along inner surface431and is retained in receiving space45, effectively preventing dirt from entering the interior of ratchet wrench10.