Patent Publication Number: US-7895924-B2

Title: Socket connection device

Description:
FIELD OF THE INVENTION 
     The present invention is related generally to a hand tool, and more particularly to a socket connection device. 
     BACKGROUND OF THE INVENTION 
       FIG. 1  shows a conventional socket connection device  10  including a main body  11  and a slide rod  12  disposed in a slide passage  13  of the main body. One end of the slide rod  12  is formed with a shallow depression  14  and a deep depression  15 . A steel ball  16  is inlaid in a through hole  17  of the main body. In normal state, the slide rod  12  is resiliently urged by a spring  18  and tends to move rightward according to  FIG. 1 . In this state, the shallow depression  14  is right under the through hole  17  and the steel ball  16  falls into the shallow depression  14  with its top edge outward protruding from the main body  11 . When pushing a push rod  19 , the slide rod  12  is moved leftward and the deep depression  15  is displaced to a position under the through hole  17 . At this time, the steel ball falls into the deep depression  15  and retracts into the main body. 
     When fitting with a socket, the push rod  19  is first pressed to move the slide rod  12  and retract the steel ball  16  into the main body  11 . Under such circumstance, the socket can be fitted with an insertion end  111  of the main body. Then, the push rod is released from the pressing force, whereby the spring  18  pushes the slide rod back to its home position where the steel ball again moves into the shallow depression  14 . In this state, the steel ball protrudes from the main body to engage with a wall of a fitting hole of the socket. When taking off the socket, the push rod  19  is pushed to move the steel ball  16  into the main body and disengage the steel ball from the socket. At this time, the socket can be separated from the connection device  10 . 
     According to the conventional socket connection device, no matter when connecting with the socket or disconnecting from the socket, a user needs to first press or pull the push rod to move the slide rod and retract the steel ball into the main body. This is quite inconvenient to the user. 
     It is impossible for the user to forcedly fit the socket with the main body without first retracting the steel ball into the main body. This is because that as shown in  FIG. 2 , the shallow depression  14  has an axial length L larger than the radius of the steel ball. That is, the center C, or to say the bottommost edge, of the steel ball falls onto a bottom wall  141  of the shallow depression  14 . Therefore, when the socket touches the steel ball and exerts a pushing force onto the steel ball, the force exerted onto the steel ball is directly applied to the bottom wall  141  of the shallow depression  14 . Therefore, it is impossible to make the slide rod  12  move. Accordingly, no matter how great the force exerted onto the steel ball by the socket is, the steel ball cannot be retracted into the main body. 
     SUMMARY OF THE INVENTION 
     It is therefore a primary object of the present invention to provide a socket connection device. A socket can be directly connected with the socket connection device without performing any pressing or pulling operation. 
     According to the above object, the socket connection device of the present invention includes: a main body; a slide rod installed in a slide passage of the main body and slidable along the slide passage; a shallow depression and a deep depression being formed on a circumference of a front end of the slide rod; and a ball body inlaid in a through hole formed on a circumference of the main body. In normal state, the slide rod is elastically pushed by a resilient member and the shallow depression is aligned with the through hole, a bottom edge of the ball body falls on the shallow depression and a top edge of the ball body protrudes out of the main body. When the slide rod moves so that the deep depression is aligned with the through hole, the ball body moves into the deep depression without protruding out of the main body. 
     In the normal state, a center of the ball body of the invention is positioned outside a bottom wall of the shallow depression. Therefore, when connecting a socket with the socket connection device, the socket presses the ball body to drive and make the slide rod slide, whereby the ball body drops into the deep depression and retracts into the main body. Therefore, the socket can be directly connected with the socket connection device. 
     Preferably, in an axial direction of the slide rod, an axial length of the shallow depression is shorter than a radius of the ball body. 
     The present invention can be best understood through the following description and accompanying drawings wherein: 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a longitudinal sectional view of a conventional socket connection device; 
         FIG. 2  is an enlarged view of a part of  FIG. 1 ; 
         FIG. 3  is a side view of a first embodiment of the present invention; 
         FIG. 4  is a longitudinal sectional of the first embodiment of the present invention; 
         FIG. 5  is an enlarged view of a part of  FIG. 4 ; 
         FIGS. 6 and 7  show that a socket is fitted onto the socket connection device of the present invention; 
         FIG. 8  shows that the socket is completely fitted on the socket connection device of the present invention; 
         FIG. 9  shows that the socket is taken off from the socket connection device of the present invention; 
         FIG. 10  is an enlarged view of a part of  FIG. 8 ; 
         FIG. 11  is a partially sectional of a second embodiment of the present invention; 
         FIG. 12  is a view according to  FIG. 11 , showing the operation of the socket connection device of the present invention; and 
         FIG. 13  is a partially sectional of a third embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The socket connection device  20  of the present invention can be an independent socket connection rod as shown in  FIG. 1 . Alternatively, the socket connection device  20  of the present invention can be applied to a ratchet wrench  70  as an internal component of a ratchet  72  of the ratchet wrench  70  as shown in  FIG. 11 . Still alternatively, the socket connection device  20  of the present invention can be applied to a socket wrench  80  as an internal component thereof as shown in  FIG. 13 . 
     Please refer to  FIGS. 3 and 4 . The socket connection device  20  includes a main body  30  having a front end as an insertion end  32 . An axial slide passage  34  is formed in the main body  30 . A through hole  36  is formed on a circumference of the insertion end  32  in communication with the slide passage  34 . 
     A slide rod  40  is installed in the slide passage  34  of the main body  30  and slidable along the slide passage. The slide rod  40  has a front end as an operation end. Referring to  FIG. 5 , a shallow depression  44  and a deep depression  45  are formed on a circumference of the operation end of the slide rod and adjacent to each other. A slope  46  is connected between the shallow depression and the deep depression. The deep depression  45  is positioned behind the shallow depression  44 . 
     A resilient member  50  is disposed inside the main body  30 . One end of the resilient member  50  abuts against a rear end of the slide rod. Accordingly, when free from any external force, the slide rod tends to move rearward to an engaging position where the shallow depression  44  is positioned under the through hole  36 . 
     By means of an operation, a user can move the slide rod  40  forward to a releasing position. For example, the socket connection device  20  can have a linking mechanism  25  including a push rod  26 . The push rod  26  is radially fitted in a hole  38  of the main body  30 . A rear end of the slide rod  40  contacts a driving section  27  of the push rod  26 . The driving section  27  can be a concave or convex structure. When pressing the push rod  26 , the push rod  26  will urge the slide rod to move forward. 
     An engaging ball body  55  is inlaid in the through hole  36  of the main body  30  and movable along the through hole  36 . In normal state, a bottom edge of the ball body  55  falls on the shallow depression  44 , whereby a top edge of the ball body protrudes out of the through hole  36 . 
     Referring to  FIG. 5 , the present invention is characterized in that in axial direction of the slide rod  40 , the axial length S of the shallow depression  44  is shorter than a radius of the ball body  55 . Therefore, a center O and a bottommost edge  551  of the ball body  55  are positioned outside a bottom wall  441  of the shallow depression  44  rather than on the bottom wall  441 . The contact range between the ball body and the shallow depression is smaller than a 90-degree arc. 
     Moreover, in this embodiment, the slide rod  40  is composed of a slender rod  41 , a large-diameter front end member  42  and a large-diameter rear end member  43 . The front end member  42  is fixedly connected with a front end of the slender rod  41 . The depressions  44 ,  45  and the slope  46  are formed on a circumference of the front end member  42 . The rear end member  43  is connected with a rear end of the slender rod and contacts the driving section  27  of the push rod  26 . The resilient member  50  is fitted on the slender rod  41 . A first end of the resilient member  50  abuts against a front face of the rear end member  43 . A second end of the resilient member  50  abuts against a shoulder section  29  of the main body. 
     In normal state, the slide rod  40  is positioned in the engaging position and the ball body is rested on the shallow depression  44  to partially protrude from the main body  30 . When connecting a socket with the socket connection device  20  of the present invention, as shown in  FIG. 6 , the socket  60  is fitted onto the insertion end  32  of the main body  30  and pushed inward. When the socket touches the ball body  55 , the socket exerts an action force onto the ball body to make the ball body retract into the main body  30 . As aforesaid, the center O of the ball body is positioned outside the bottom wall  441  of the shallow depression  44 . Therefore, a convex face of the ball body contacts the bottom wall  441  rather than the bottommost edge  551  of the ball body. Therefore, the ball body  55  can push the slide rod  40  and urges the slide rod to move forward along the slide passage  34  so that the shallow depression  44  moves away from the through hole  36 , as shown in  FIG. 7 , while the deep depression  45  approaches the through hole  36 . Under such circumstance, the ball body  55  leaves the shallow depression  44  and overpasses the slope  46  to drop into the deep depression  45 . Accordingly, the ball body is retracted into the through hole without protruding from the main body. 
     When further pushing the socket  60 , a recessed section  64  formed on an inner wall of the fitting hole  62  of the socket is moved to a position above the ball body  55 . At this time, the ball body is released from the pressing of the socket, whereby the resilient member  50  pushes the slide rod  40  back to the engaging position where the ball body  55  moves back into the shallow depression  44 , the top edge of the ball body again protrudes out of the through hole to engage in the recessed section  64  of the fitting hole  62  and lock the socket with the socket connection device  20  as shown in  FIG. 8 . 
     When taking off the socket, a user needs to press the push rod  26  and make the slide rod  40  move forward to the releasing position as shown in  FIG. 9 , the shallow depression  44  moves away from the through hole  36  and the deep depression  45  moves to a position under the through hole. Under such circumstance, the ball body  55  drops into the deep depression  45  without engaging with the socket  60 . In this case, the socket can be disconnected from the socket connection device  20 . After that, releasing the push rod  26  from the pressing force, the resilient member  50  urges the slide rod  40  to restore to the engaging position where the ball body partially protrudes from the main body. 
     In use of the present invention, a user only needs to fit the socket onto the socket connection device for locking the socket therewith. It is unnecessary for the user to perform any additional operation (such as operation of the linking mechanism  25 ). When taking off the socket, the user needs to perform an operation to retract the ball body into the main body for separating the socket  60  from the socket connection device  20 . Referring to  FIG. 10 , it is impossible to directly take off the socket from the socket connection device  20  without first retracting the ball body  55  into the main body. This is because under such circumstance, the action force f exerted by the socket onto the ball body is directed to the shallow depression  44  and thus the ball body can hardly drive and move the slide rod. 
       FIGS. 11 and 12  show a second embodiment of the socket connection device of the present invention, in which the same components are denoted by the same reference numerals as the first embodiment. 
     In this embodiment, the main body  30  is connected with the ratchet  72  of the ratchet wrench  70 . The rear end of the slide rod  40  protrudes from the ratchet  72 . In normal state, under the resilient force of the resilient member  55 , the slide rod  40  is positioned in the engaging position where the top edge of the ball body  55  protrudes from the main body. When fitting a socket onto the insertion section  32  of the main body, the socket can directly urges the ball body  55  to retract into the main body for locking the socket. This operation is identical to that of the first embodiment. 
     When taking off the socket, as shown in  FIG. 12 , a user needs to press the slide rod  40  and make the slide rod  40  move forward to the releasing position where the ball body  55  retracts into the main body. 
       FIG. 13  shows a third embodiment of the socket connection device of the present invention, in which the main body  30  is connected with a head section  82  of the wrench  80 . The locking and releasing operations of this embodiment are identical to those of the first and second embodiments. 
     According to the present invention, when connecting the socket with the socket connection device by means of insertion, a user can directly fit the socket onto the socket connection device to lock the socket therewith without performing any other operation. Therefore, it is very convenient to use the socket connection device. 
     The above embodiments are only used to illustrate the present invention, not intended to limit the scope thereof. Many modifications of the above embodiments can be made without departing from the spirit of the present invention.