Patent Publication Number: US-7587961-B1

Title: Reversible ratchet tool

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to a reversible ratchet tool, and more particularly to a reversible ratchet tool including a control pawl device for controlling the driving or rotating direction of the reversible ratchet tool, and for allowing reversible ratchet tool to be selectively driven or rotated in either of the directions or in both directions by the user. 
   2. Description of the Prior Art 
   Typical reversible ratchet tools comprise a cylindrical block rotatably received in a post compartment of a head portion of a handle, and a number of posts engaged between the cylindrical block and the head portion of the handle, and a lever switch coupled to the posts with a post plate for actuating the posts to be engaged in the selected position between the cylindrical block and the head portion of the handle, and for controlling the driving or rotating direction of the cylindrical block with the head portion of the handle. 
   For example, U.S. Pat. No. 4,873,898 to Chern discloses one of the typical ratchetless reversible wrenches also comprising a number of posts engaged between a cylindrical block and a head portion of a handle, and a lever switch coupled to the posts with a post plate for actuating the posts to be engaged in the selected position between the cylindrical block and the head portion of the handle, and for controlling the driving or rotating direction of the cylindrical block. 
   However, the driving or rotating direction of the cylindrical block by the head portion of the handle may only be reversed, or may only be driven or rotated in either of the directions, but may not be driven or rotated in both directions with the head portion of the handle by the user. 
   U.S. Pat. No. 5,174,176 to Krivec discloses another typical reversible ratchet wrench comprising a ratchet wheel rotatably received in a housing, and a reversing pawl unit including two pawls connected to a pivotally mounted reversing cam by leaf springs. 
   However, similarly, the driving or rotating direction of the ratchet wheel by a housing of the handle may only be reversed, but may not be driven or rotated in both directions with the housing by the user. 
   U.S. Pat. No. 5,499,559 to Lin discloses a further typical reversible ratchet or socket wrench comprising an adapter rotatably received in an adapter holder, and a number of roller bearings engaged between the adapter and the adapter holder for controlling the driving or rotating direction of the adapter. 
   However, similarly, the driving or rotating direction of the adapter by the adapter housing may only be reversed, but may not be driven or rotated in both directions with the adapter housing by the user. 
   U.S. Pat. No. 5,622,089 to Gifford, Sr. discloses a still further typical reversible ratchet wrench comprising a large circular gear rotatably received in an outboard section of a circular shaped head, and two bevel arms disposed in an inboard section of the circular shaped head, and an upstanding biasing member having a triangular configuration with rounded edges and disposed between the two bevel arms for actuating the bevel arms to selectively engage with the circular gear and for controlling the driving or rotating direction of the circular gear. 
   However, similarly, the driving or rotating direction of the circular gear may only be reversed, but may not be driven or rotated in both directions with the handle by the user. 
   The present invention has arisen to mitigate and/or obviate the afore-described disadvantages of the conventional reversible ratchet tools. 
   SUMMARY OF THE INVENTION 
   The primary objective of the present invention is to provide a reversible ratchet tool including a control pawl device for controlling the driving or rotating direction of the reversible ratchet tool, and for allowing reversible ratchet tool to be selectively driven or rotated in either of the directions or to be selectively driven or rotated in both directions by the user. 
   In accordance with one aspect of the invention, there is provided a reversible ratchet tool comprising a housing including a chamber and a compartment formed in the housing and communicating with each other, and including two curved recesses formed therein and communicating with the compartment of the housing, and including an orifice formed therein and communicating with the compartment of the housing, a rotary member rotatably received in the chamber of the housing and including a driving stem extended outwardly therefrom, and including a number of teeth provided on an outer peripheral portion thereof, and a cover secured to the housing for closing the chamber and the compartment of the housing, and including an opening formed therein for receiving the driving stem of the rotary member and for allowing the driving stem of the rotary member to be extended out through the opening of the cover and to be extended out of the housing, the cover including an axle extended therefrom and including three depressions formed therein and located and arranged around the axle, two pawl members received and engaged in the compartment of the housing, and each including a rounded end pivotally engaged in the curved recesses of the housing for pivotally mounting the pawl members to the housing, and each including at least one tooth formed on another end portion thereof for selectively engaging with the teeth of the rotary member, two spring members disposed in the compartment of the housing and engaged with the pawl members for biasing the pawl members to engage with the teeth of the rotary member respectively, an actuating member received in the compartment of the housing, and including a cavity formed therein for pivotally receiving the axle of the cover and for pivotally securing the actuating member in the housing, and including a projection extended from the actuating member for engaging with either of the depressions of the cover and for positioning the actuating member to the housing at the selected positions, and a hand grip rotatably engaged with the orifice of the housing and coupled to the actuating member for rotating the actuating member relative to the housing and for actuating the actuating member to selectively engage with the pawl members, and the actuating member is rotated relative to the housing and the cover with the hand grip to engage with either of the pawl members and to disengage either of the pawl members from the rotary member and for allowing the rotary member to be rotated in either direction by the housing, and both of the pawl members being biased and forced to engage with the teeth of the rotary member for allowing the rotary member to be rotated in both directions by the housing when the actuating member is centered and is not rotated relative to the housing and the cover and is not engaged with both of the pawl members. 
   The hand grip includes an aperture formed therein for slidably receiving a free end portion of the actuating member, and the actuating member includes a hole formed therein for receiving a spring element, and the spring element is engaged between the actuating member and the hand grip and biases the projection of the actuating member to engage with either of the depressions of the cover and for positioning the actuating member to the housing at the selected positions. 
   The rotary member includes a detent slidably received in the driving stem of the rotary member, and includes a control device slidably engaged into the rotary member and engaged with the detent for actuating the detent to selectively move out of the driving stem of the rotary member. 
   Further objectives and advantages of the present invention will become apparent from a careful reading of the detailed description provided hereinbelow, with appropriate reference to the accompanying drawings. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a perspective view of a reversible ratchet tool in accordance with the present invention; 
       FIG. 2  is a partial exploded view illustrating a portion of the reversible ratchet tool; 
       FIG. 3  is a further partial exploded view of the reversible ratchet tool; 
       FIGS. 4 ,  5  are cross sectional views of the reversible ratchet tool taken along lines  4 - 4 , and  5 - 5  of  FIG. 1  respectively; and 
       FIGS. 6 ,  7  are cross sectional views similar to  FIG. 5 , illustrating the operation of the control pawl device of the reversible ratchet tool. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
   Referring to the drawings, and initially to  FIGS. 1-5 , a reversible ratchet tool in accordance with the present invention comprises a handle  10  including a head or housing  11  formed or provided on one end portion thereof, and including a chamber  12  and a compartment  13  formed in the housing  11  and communicating with each other, a wheel gear or rotary member  20  is rotatably received in the chamber  12  of the housing  11  and includes a driving stem  21  extended outwardly therefrom, and includes a number of teeth  22  formed or provided on the outer peripheral portion thereof, and includes a detent  23  slidably received in the driving stem  21  of the rotary member  20 , and includes a control device  24  slidably engaged into the rotary member  20  and engaged with the detent  23  for actuating the detent  23  to selectively move out of the driving stem  21  of the rotary member  20  and for forcing or actuating the detent  23  to selectively engage with a driven member (not shown) and to detachably attach or secure or couple the driven member to the driving stem  21  of the rotary member  20 . 
   A cap or cover  25  is attached to the housing  11  and secured to the housing  11  with one or more (such as two) fasteners  26  for blocking or closing the chamber  12  and the compartment  13  of the housing  11 , and includes an opening  27  formed therein for receiving the driving stem  21  of the rotary member  20  and for allowing the driving stem  21  of the rotary member  20  to be extended out through the opening  27  of the cover  25  and to be extended out of the housing  11  for engaging with the driven member. The cover  25  further includes an axle  28  extended therefrom ( FIG. 3 ), and includes one or more (such as three) depressions  29  formed therein and located or arranged around the axle  28 . The housing  11  includes two curved recesses  14  formed therein and communicating with the compartment  13  of the housing  11 , and includes an orifice  15  formed therein and also communicating with the compartment  13  of the housing  11 . 
   Two pawl members  30  are received or engaged in the compartment  13  of the housing  11 , and each include a rounded end  31  pivotally or rotatably received or engaged in the curved recesses  14  of the housing  11  for pivotally or rotatably attaching or mounting the pawl members  30  to the housing  11 , and each include one or more teeth  32  formed or provided on the other end portion thereof for selectively engaging with the teeth  22  of the rotary member  20  ( FIGS. 5-7 ) and for controlling the driving or rotating direction of the rotary member  20  by the housing  11  of the handle  10 . One or more (such as two) spring members  33  are disposed or received or engaged in the compartment  13  of the housing  11  and engaged with the pawl members  30  respectively for biasing or forcing the pawl members  30  to engage with the teeth  22  of the rotary member  20  respectively. 
   An operating or actuating device or control pawl device  5  includes a post or cam or actuating member  50  received or engaged in the compartment  13  of the housing  11 , and includes a cavity  51  formed or provided in one end portion of the actuating member  50  for pivotally or rotatably attaching or receiving the axle  28  of the cover  25  and for pivotally or rotatably attaching or securing the actuating member  50  in the housing  11 , and includes a projection  52  extended from the actuating member  50  for engaging with either of the depressions  29  of the cover  25  and for anchoring or positioning the actuating member  50  to the housing  11  at the predetermined or selected positions. A knob or hand grip  53  is pivotally or rotatably engaged with the orifice  15  of the housing  11 , and attached or secured or coupled to the actuating member  50  for rotating the actuating member  50  relative to the housing  11  and for operating or actuating the actuating member  50  to selectively engage with the pawl members  30 . 
   As best shown in  FIGS. 2-4 , the hand grip  53  includes an aperture  54  formed therein for slidably receiving or engaging with a free end portion  55  of the actuating member  50 , and the actuating member  50  includes a hole  56  formed therein for receiving a spring element  57  which is engaged between the actuating member  50  and the hand grip  53  and which may bias or force the projection  52  of the actuating member  50  to selectively engage with either of the depressions  29  of the cover  25  and for anchoring or positioning the actuating member  50  to the housing  11  at the predetermined or selected positions. As shown in  FIGS. 5-7 , the actuating member  50  includes a substantially rounded triangular cross section for engaging with and for disengaging either of the pawl members  30  from the rotary member  20  ( FIGS. 5 ,  6 ) when the actuating member  50  is rotated relative to the housing  11  and the cover  25 , and arranged for allowing both of the pawl members  30  to engage with the rotary member  20  ( FIG. 7 ) when the actuating member  50  is centered or is not rotated relative to the housing  11  and the cover  25 . 
   In operation, as shown in  FIG. 4 , the actuating member  50  may be rotated relative to the housing  11  and the cover  25  with the hand grip  53  to engage with one of the pawl members  30  and to disengage the right pawl member  30  from the rotary member  20  ( FIG. 5 ) for allowing the rotary member  20  to be driven or rotated clockwise by the housing  11  of the handle  10 . On the contrary, as shown in  FIG. 6 , when the left pawl member  30  is disengaged from the rotary member  20  by the actuating member  50 , the rotary member  20  may be driven or rotated counterclockwise by the housing  11  of the handle  10 . As shown in  FIG. 7 , when the actuating member  50  is centered or is not rotated relative to the housing  11  and the cover  25  and is not engaged with both of the pawl members  30 , both of the pawl members  30  may be biased or forced to engage with the teeth  22  of the rotary member  20  respectively for allowing the rotary member  20  to be driven or rotated in both directions by the housing  11  of the handle  10 . 
   Accordingly, the reversible ratchet tool in accordance with the present invention includes a control pawl device for controlling the driving or rotating direction of the reversible ratchet tool, and for allowing reversible ratchet tool to be selectively driven or rotated in either of the directions or to be selectively driven or rotated in both directions by the user. 
   Although this invention has been described with a certain degree of particularity, it is to be understood that the present disclosure has been made by way of example only and that numerous changes in the detailed construction and the combination and arrangement of parts may be resorted to without departing from the spirit and scope of the invention as hereinafter claimed.