Patent Publication Number: US-8122794-B2

Title: Torque socket assembly

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a torque socket assembly, and more particularly, to a torque socket assembly with improved structure and providing a stable torque value 
     2. Description of Related Art 
     A conventional torque socket assembly commonly known in accordance with the prior art comprises a receiving portion, a driving portion, and a middle portion disposed in between the receiving portion and the driving portion. The receiving portion has a quadrangular hole for adapting to co-operate with a driving tool. The driving portion is a polygon-shaped hole for adapting to receive a fastener (i.e. a bolt). The middle portion has a plurality of embossed patterns and a plurality of smooth faces alternately and annularly formed on the outer periphery thereof. The embossed patterns provide increment to the friction when the socket assembly is grasped by hands, such that a user may selectively adapts the socket assembly to a driving tool or simply grasps the socket assembly by hands for operation. 
     However, the conventional socket assembly bears several disadvantages. First of all, the conventional socket assembly does not include a torque adjusting unit therefore it is not capable to provide a predetermined torque. When in operation, the user can merely tightened the fastener with an object, and is unable to determine whether the torque applied is sufficient to securely fasten the fastener with the object. In addition, the user is not acknowledged if the torque applied has reached the torque required, which may consequently lead to over-tightening of the fastener, such that the structure of the socket assembly is easily damaged due to over-tightening. Nevertheless, high precision in a torque applied is often required when applying a socket assembly to fasten a fastener with the object; even minor errors in the torque applied may lead to unexpected result. Due to the lack of the torque adjusting unit of the conventional socket assembly, when a stable torque is required for fastening a series of fasteners, it is difficult for the user to apply a same force continuously, which may easily lead to slight variations in the torque values. Therefore, the conventional socket assembly is inconvenient to use. 
     The present invention has arisen to obviate/mitigate the disadvantages of the conventional torque socket assembly. 
     SUMMARY OF THE INVENTION 
     The main objective of the present invention is to provide a torque socket assembly which has an improved structure and provides a stable torque value. 
     To achieve the objective, a torque socket assembly in accordance with the present invention comprises a base which has a securing hole laterally defined therein. The base has a connecting portion formed on one end thereof, which is adapted to connect with a driving tool. Another end of the base has a receiving hole defined therein. A securing flange is annularly formed on an outer periphery of the base. 
     A tube sleeves on the base. The tube has a first portion and a second portion which is connected with the first portion. The first portion has a recess defined in an outer periphery thereof. The recess has a through hole defined in a bottom thereof. Two inclined inner walls are oppositely formed on two sides of the recess. The second portion has a driving hole defined in one end thereof. The first portion partially sleeves on an outer periphery of the base such that the receiving hole communicates with the driving hole of the second portion. 
     A torque setting unit includes a first teethed gear which is disposed in the receiving hole, a second teethed gear which meshes with the first teethed gear, a resilient unit which abuts against the second teethed gear and a bottom of the second portion, and a rod which axially passes through the resilient unit, the first teethed gear and the second teethed gear. One end of the rod is threadedly secured in the base. Another end of the rod has a driving portion formed thereon which is adapted to receive a driver. The first teethed gear and the second teethed gear are polygon-shaped. The second teethed gear has an indentation formed on an outer surface thereof. A fastener is screwed into the securing hole of the base and is abutted against the rod for confining the rod from rotating relative to the base. 
     A securing unit includes a pin which is disposed in the recess in the first portion, a spring which sleeves on an outer periphery of the first portion of the tube and contacts with the pin, and an outer sleeve which has an inner shoulder annularly formed on an inner periphery of one end thereof for abutting against the spring. The outer sleeve slidably sleeves on outer peripheries of the spring and the tube, and is abutted against the securing flange of the base, such that the outer sleeve is prevented from overly sleeving on the base. 
     Accordingly, by securing the rod within the base, the resilient unit is compressed, such that the resilient unit, the first and the second teethed gear provide a stable torque value. When an applying force exceeds the stable torque value provided, the second teethed gear is abutted against the first teethed gear and slidably disengaged from the first teethed gear, such that the indentation of the second teethed gear corresponds to the through hole of the recess, and the pin disposed in the recess falls in the indentation and is abutted against the indentation of the second teethed gear via the through hole for refraining the second teethed gear from engaging with the first teethed gear. 
     In accordance with another aspect of the present invention, an elastic unit is disposed in the receiving hole. The elastic unit is abutting against a bottom of the receiving hole and the first teethed gear. 
     Further benefits and advantages of the present invention will become apparent after a careful reading of the detailed description with appropriate reference to the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an exploded perspective view to show a torque socket assembly in accordance with the present invention; 
         FIG. 2  is an assembled perspective view of the torque socket assembly in accordance with the present invention; 
         FIG. 3  is a cross sectional view to show a first and a second teethed gear of the torque socket assembly in accordance with the present invention meshed with each other; 
         FIG. 4  is a cross sectional view to show a pin disposed in the recess of the first portion of a tube in accordance with the present invention falls into an indentation of the second teethed gear when the second teethed gear is disengaged from the first teethed gear; 
         FIG. 5  is an exploded perspective view to show a second embodiment of the torque socket assembly in accordance with the present invention; 
         FIG. 6  is a cross sectional view to show the first and second teethed gear of the torque socket of the second embodiment of the torque socket assembly in accordance with the present invention meshed with each other; and 
         FIG. 7  is a cross sectional view to show the pin disposed in the recess of the first portion of the tube of the second embodiment of the torque socket assembly in accordance with the present invention falls into the indentation of the second teethed gear when the second teethed gear is disengaged from the first teethed gear. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to  FIGS. 1-4 , a torque socket assembly in accordance with the present invention comprises a base  1  which has a securing hole  110  laterally defined therein. The base  1  has a connecting portion  11  formed on one end thereof. The base  1  is adapted to connect with a driving tool (i.e. a pneumatic hand tool). Another end of the base  1  has a receiving hole  12  defined therein. A securing flange  13  is annularly formed on an outer periphery of the base  1 . 
     A tube  2  sleeves on the base  1 . The tube  2  has a first portion  22  and a second portion  21  which is connected with the first portion  22 . The first portion  22  has a recess  220  defined in an outer periphery thereof. The recess  220  has a through hole  221  defined in a bottom thereof. Two inclined inner walls  2201  are oppositely formed on two sides of the recess  220 . The second portion  21  has a driving hole  23  defined in one end thereof. The first portion  22  partially sleeves on an outer periphery of the base  1  such that the receiving hole  12  communicates with the driving hole  23  of the second portion  21  and the base  1  is rotatable relative to the tube  2 . 
     A torque setting unit  3  includes a first teethed gear  31  which is disposed in the receiving hole  12 , a second teethed gear  32  which meshes with the first teethed gear  31 , a resilient unit  33  which abuts against the second teethed gear  32  and a bottom of the second portion  21 , and a rod  34  which axially passes through the resilient unit  33 , the first teethed gear  31  and the second teethed gear  32 . The first teethed gear  31  has a series of first teeth (not numbered) extending upwardly from a top thereof. The second teethed gear  32  has a series of second teeth (not numbered) extending upwardly from a top thereof and correspond to the first teeth (as shown in  FIGS. 1 and 3 ), such that the first teeth and the second teeth meshed with each other. One end of the rod  34  has a threaded portion (not numbered) formed thereon. The threaded portion of the rod  34  is threadedly secured in the base  1 . Another end of the rod  34  has a driving portion  340  formed thereon which is adapted to receive a driver (not shown). A fastener  111  is screwed into the securing hole  110  of the base  1  and is abutted against the rod  34  for confining the rod  34  from rotating relative to the base  1 . Moreover, the first teethed gear  31  and the second teethed gear  32  are polygon-shaped, such that the first and the second teethed gear  31 ,  32  are firmly secured. In the present embodiment, the first and the second teethed gear  31   32  are hexagonal (as shown in  FIG. 1 ). The second teethed gear  32  has an indentation  320  formed on an outer surface thereof. 
     A securing unit  4  includes a pin  41  which is disposed in the recess  220  in the first portion  22 , a spring  42  which sleeves on an outer periphery of the first portion  22  of the tube  2  and contacts with the pin  41 , and an outer sleeve  43  which has an inner shoulder  431  annularly formed on an inner periphery of one end thereof for abutting against the spring  42 . The outer sleeve  43  slidably sleeves on outer peripheries of the spring  42  and the tube  2 , and is abutted against the securing flange  13  of the base  1 , therefore, the outer sleeve  43  is prevented from overly sleeving on the base  1 . The second teethed gear  32  is partially protruded from the through hole  221  of the recess  220  and slightly abuts against the pin  41 , such that the pin  41  is slightly detached from the bottom of the recess  220 . 
     Accordingly, by securing the rod  34  within the base  1 , the resilient unit  33  is compressed, such that the resilient unit  33 , the first and the second teethed gear  31 ,  32  provide a stable torque value. 
     As shown in  FIG. 4 , when an applying force exceeds the stable torque value provided, the second teethed gear  32  abuts against the first teethed gear  31  and slidably disengaged from the first teethed gear  31 , such that the indentation  320  of the second teethed gear  32  corresponds to the through hole  221  of the recess  220 , and the pin  41  which is disposed in the recess  220  falls in the indentation  320  and is abutted against the indentation  320  of the second teethed gear  32  via the through hole  221  for refraining the second teethed gear  32  from engaging with the first teethed gear  31 . Therefore, when the applying force exceeds the stable torque value provided, the first teethed gear  31  idlingly rotates with the base  1  relative to the second teethed gear  32 , preventing the first and second teethed gear  31 ,  32  from wearing due to continuous collision with each other. 
     When a user slides the outer sleeve  43  toward the driving hole  23 , the inner shoulder  431  of the outer sleeve  43  abuts against and compresses the spring  42 . When the spring  42  is compressed, the pin  41  which contacts with the spring  42  and abuts against the indentation  320  of the second teethed gear  32  is lifted by the compressed spring  42 , such that the pin  41  is guided along the inclined inner wall  2201  and disengages from the indentation  320  of the second teethed gear  32 . When the pin  41  is disengaged from the indentation  320  of the second teethed gear  32 , the resilient unit  33  pushes the second teethed gear  32  to engage with the first teethed gear  31 , such that the second teethed gear  32  is reinstated to mesh with the first teethed gear  31  ( FIG. 3 ). The torque socket assembly is thereby reinstated to the preset stable torque value. When the user releases the outer sleeve  43 , an elastic force of the spring  42  pushes the outer sleeve  43  to abut against the securing flange  13  of the base  1 , allowing the user to instantly access the driver again. 
     With reference to  FIG. 5  to  FIG. 7 , that shows a second embodiment of the torque socket assembly in accordance with the present invention. The elements and effects of the second embodiment which are the same with the first embodiment are not described, only the differences are described. In this embodiment, an elastic unit  35  is disposed in the receiving hole  12 . The elastic unit  35  is abutted against a bottom of the receiving hole  12  and the first teethed gear  31 . The elastic unit  35  co-operates with the resilient unit  33 , such that the first and the second teethed gear  31   32  are evenly applied by the resilient unit  33  and the elastic unit  35 . In addition, a co-operation of the resilient unit  33  and the elastic unit  35  provides a wider range of the torque value that can be preset. 
     Although the invention has been explained in relation to its preferred embodiment, it is to be understood that many other possible modifications and variations can be made without departing from the spirit and scope of the invention as hereinafter claimed.