Ratchet wrench structure

Information

  • Patent Grant
  • 6513409
  • Patent Number
    6,513,409
  • Date Filed
    Friday, January 25, 2002
    22 years ago
  • Date Issued
    Tuesday, February 4, 2003
    21 years ago
  • Inventors
  • Examiners
    • Meislin; D. S.
    Agents
    • Baxley; Charles E.
Abstract
The present invention relates to a ratchet wrench structure including a wrench body, a ratchet wheel, a pawl member, and a control knob. The wrench body has a drive head formed with an operation space for receiving the ratchet wheel, a control space for receiving the control knob, a connecting space between the operation space and the control space for receiving the pawl member. The pawl member is provided with a control spring that is provided with a control ring. The control knob has a control rod is passed through the control ring of the control spring, for moving and displacing the control ring of the control spring.
Description




BACKGROUND OF THE INVENTION




1. Field of the Invention




The present invention relates to a ratchet wrench structure, and more particularly to a ratchet wrench structure which has a simple construction and may be processed easily.




2. Description of the Related Art




A conventional ratchet wrench structure in accordance with the prior art shown in

FIGS. 7 and 8

comprises a wrench body


50


, a ratchet wheel


60


, a pawl member


70


, and a control knob


80


.




The wrench body


50


has a distal end formed with a drive head


52


. The drive head


52


of the wrench body


50


has a first side formed with an operation space


520


for receiving the ratchet wheel


60


and the pawl member


70


, and a second side formed with a control space


522


for receiving the control knob


80


. The operation space


520


of the drive head


52


of the wrench body


50


has a top portion formed with an annular flange


521


, and a bottom portion formed with a depression


523


. The operation space


520


of the drive head


52


of the wrench body


50


has a wall formed with a recess


529


. The drive head


52


of the wrench body


50


is formed with a screw hole


525


and a receiving hole


528


located in the control space


522


of the drive head


52


of the wrench body


50


.




The ratchet wheel


60


is mounted in the operation space


520


of the drive head


52


of the wrench body


50


, and has an outer wall formed with multiple ratchet teeth


62


. A snap ring


64


is secured in the depression


523


of the operation space


520


of the drive head


52


of the wrench body


50


, so that the ratchet wheel


60


may be retained in the operation space


520


of the drive head


52


of the wrench body


50


by the annular flange


521


and the snap ring


64


.




The pawl member


70


is pivotally mounted in the operation space


520


of the drive head


52


of the wrench body


50


, and has a first side formed with multiple engaging teeth


72


detachably meshing with the ratchet teeth


62


of the ratchet wheel


60


, and a second side formed with a recess


76


for receiving a first end of a spring


74


whose second end is received in the recess


529


of the operation space


520


of the drive head


52


of the wrench body


50


. The pawl member


70


is provided with two rods


78


.




The control knob


80


is rotatably mounted in the control space


522


of the drive head


52


of the wrench body


50


, and is formed with a control lever


81


for rotating the control knob


80


. The control knob


80


is formed with a slot


85


for receiving the two rods


78


of the pawl member


70


. A screw


87


is extended through a counterbore


82


formed in the control knob


80


, and is screwed into the screw hole


525


of the wrench body


50


. The control knob


80


is formed with multiple positioning holes


84


. A spring


86


is received in the receiving hole


528


of the wrench body


10


, for urging a ball


88


which may be positioned in one of the positioning holes


84


of the control knob


80


.




In operation, the control knob


80


may be rotated to turn the two rods


78


of the pawl member


70


, thereby pivoting the pawl member


70


, so that the engaging teeth


72


of the pawl member


70


may mesh with the ratchet teeth


62


of the ratchet wheel


60


, so as to rotate a workpiece.




However, such a conventional ratchet wrench structure has a very complicated construction, so that it cannot be processed easily. For example, the control knob


80


needs to be processed with a slot


85


, a counterbore


82


, and multiple positioning holes


84


, the pawl member


70


needs to processed with a recess


76


and two rods


78


, and the wrench body


50


needs to be processed with a recess


529


, a screw hole


525


and a receiving hole


528


. In addition, the spring


74


is easily detached from the recess


76


of the pawl member


70


and the recess


529


of the wrench body


50


, thereby jamming and failing the conventional ratchet wrench structure.




SUMMARY OF THE INVENTION




The present invention has arisen to mitigate and/or obviate the disadvantage of the conventional ratchet wrench structure.




The primary objective of the present invention is to provide a ratchet wrench structure which has a simple construction, and may be processed easily.




Another objective of the present invention is to provide a ratchet wrench structure which may be assembled and dismantled conveniently and easily.




A further objective of the present invention is to provide a ratchet wrench structure, wherein the control spring is secured on the pawl member and retained by the control rod, so that the control spring may be positioned rigidly and stably without detachment.




In accordance with the present invention, there is provided a ratchet wrench structure, comprising: a wrench body, a ratchet wheel, a pawl member, and a control knob, wherein:




the wrench body has a distal end formed with a drive head, the drive head of the wrench body has a first side formed with an operation space for receiving the ratchet wheel, and a second side formed with a control space for receiving the control knob, the drive head of the wrench body is formed with a connecting space connected between the operation space and the control space for receiving the pawl member;




the ratchet wheel is mounted in the operation space of the drive head of the wrench body, and has an outer wall formed with multiple ratchet teeth;




the pawl member is pivotally mounted in the connecting space of the drive head of the wrench body, and has a first side and a second side, the first side of the pawl member is formed with multiple engaging teeth detachably meshing with the ratchet teeth of the ratchet wheel, a control spring has a first end secured to a center of the second side of the pawl member, and a second end provided with a control ring that is extended into the control space of the drive head of the wrench body; and




the control knob is rotatably mounted in the control space of the drive head of the wrench body, and has a side integrally formed or provided with a control lever for rotating the control knob, a control rod is eccentrically secured on a bottom of the control knob to rotate with the control knob, and is passed through the control ring of the control spring, for moving and displacing the control ring of the control spring.




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 a perspective view of a ratchet wrench structure in accordance with a preferred embodiment of the present invention;





FIG. 2

is an exploded view of the ratchet wrench structure as shown in

FIG. 1

;





FIG. 3

is a partially cut-away front plan cross-sectional view of the ratchet wrench structure as shown in

FIG. 1

;





FIG. 4

is a partially cut-away top plan cross-sectional view of the ratchet wrench structure as shown in

FIG. 1

;





FIG. 5

is a schematic operational view of the ratchet wrench structure as shown in

FIG. 4

in use;





FIG. 6

is a schematic operational view of the ratchet wrench structure as shown in

FIG. 4

in use;





FIG. 7

is an exploded perspective view of a conventional ratchet wrench structure in accordance with the prior art; and





FIG. 8

is a partially cut-away front plan cross-sectional assembly view of the conventional ratchet wrench structure as shown in FIG.


7


.











DETAILED DESCRIPTION OF THE INVENTION




Referring to the drawings and initially to

FIGS. 1-4

, a ratchet wrench structure in accordance with a preferred embodiment of the present invention comprises a wrench body


10


, a ratchet wheel


20


, a pawl member


30


, and a control knob


40


.




The wrench body


10


has a distal end formed with a drive head


12


. The drive head


12


of the wrench body


10


has a first side formed with an operation space


120


for receiving the ratchet wheel


20


, and a second side formed with a control space


122


for receiving the control knob


40


. The drive head


12


of the wrench body


10


is also formed with a connecting space


124


connected between the operation space


120


and the control space


122


for receiving the pawl member


30


.




The operation space


120


of the drive head


12


of the wrench body


10


has a top portion formed with an annular flange


121


, and a bottom portion formed with an annular depression


123


. The control space


122


of the drive head


12


of the wrench body


10


has a wall formed with an annular snap groove


126


. The wrench body


10


is formed with multiple positioning holes


128


located adjacent to the control space


122


of the drive head


12


of the wrench body


10


.




The ratchet wheel


20


is mounted in the operation space


120


of the drive head


12


of the wrench body


10


, and has an outer wall formed with multiple ratchet teeth


22


. A substantially C-shaped snap ring


24


is secured in the annular depression


123


of the operation space


120


of the drive head


12


of the wrench body


10


, so that the ratchet wheel


20


may be retained in the operation space


120


of the drive head


12


of the wrench body


10


by the annular flange


121


and the snap ring


24


.




The pawl member


30


is pivotally mounted in the connecting space


124


of the drive head


12


of the wrench body


10


, and has a first end


31


and a second end


33


, and has a first side and a second side. The first side of the pawl member


30


is formed with multiple engaging teeth


32


detachably meshing with the ratchet teeth


22


of the ratchet wheel


20


. A control spring


34


has a first end secured to a center of the second side of the pawl member


30


, and a second end provided with a control ring


36


that is extended into the control space


122


of the drive head


12


of the wrench body


10


.




The control knob


40


having a circular shape is rotatably mounted in the control space


122


of the drive head


12


of the wrench body


10


, and has a side integrally formed or provided with a control lever


41


for rotating the control knob


40


. A control rod


42


is eccentrically secured on a bottom of the control knob


40


to rotate with the control knob


40


, and is passed through the control ring


36


of the control spring


34


, for moving and displacing the control ring


36


of the control spring


34


.




The control lever


41


of the control knob


40


has a bottom formed with a receiving recess


44


for receiving an urging spring


46


and a positioning ball


48


. The positioning ball


48


may be moved by the control lever


41


of the control knob


40


to be positioned in one of the multiple positioning holes


128


of the wrench body


10


, thereby providing a temporary positioning effect to the control lever


41


of the control knob


40


.




The control knob


40


has a periphery formed with an annular retaining groove


43


. A substantially C-shaped retaining ring


45


is secured between the retaining groove


43


of the control knob


40


and the snap groove


126


of the control space


122


of the drive head


12


of the wrench body


10


, for retaining the control knob


40


in the control space


122


of the drive head


12


of the wrench body


10


.




In operation, referring to

FIGS. 4-6

with reference to

FIGS. 1-3

, the control lever


41


and the control rod


42


of the control knob


40


is initially in line with the control spring


34


of the pawl member


30


as shown in

FIG. 4

, so that the engaging teeth


32


of the pawl member


30


is disengaged from the ratchet teeth


22


of the ratchet wheel


20


. Thus, when the drive head


12


of the wrench body


10


is rotated, the ratchet wheel


20


is not rotated with the drive head


12


of the wrench body


10


, so that the drive head


12


of the wrench body


10


idles.




The control lever


41


of the control knob


40


may be driven to move from the position as shown in

FIG. 4

to the position as shown in

FIG. 5

to rotate the control knob


40


which moves the control rod


42


which moves the control ring


36


which turns the control spring


34


which pivots the pawl member


30


, so that the engaging teeth


32


at the first end


31


of the pawl member


30


may mesh with the ratchet teeth


22


of the ratchet wheel


20


as shown in FIG.


5


.




Thus, when the drive head


12


of the wrench body


10


is rotated clockwise, the ratchet wheel


20


may be rotated with the drive head


12


of the wrench body


10


to rotate a workpiece clockwise. When the drive head


12


of the wrench body


10


is rotated counterclockwise, the ratchet wheel


20


is not rotated with the drive head


12


of the wrench body


10


, so that the drive head


12


of the wrench body


10


idles. Thus, the ratchet wheel


20


may be rotated with the drive head


12


of the wrench body


10


to rotate clockwise only.




Alternatively, the control lever


41


of the control knob


40


may be driven to move from the position as shown in

FIG. 4

to the position as shown in

FIG. 6

to rotate the control knob


40


which moves the control rod


42


which moves the control ring


36


which turns the control spring


34


which pivots the pawl member


30


, so that the engaging teeth


32


at the second end


33


of the pawl member


30


may mesh with the ratchet teeth


22


of the ratchet wheel


20


as shown in FIG.


6


.




Thus, when the drive head


12


of the wrench body


10


is rotated counterclockwise, the ratchet wheel


20


may be rotated with the drive head


12


of the wrench body


10


to rotate a workpiece counterclockwise. When the drive head


12


of the wrench body


10


is rotated clockwise, the ratchet wheel


20


is not rotated with the drive head


12


of the wrench body


10


, so that the drive head


12


of the wrench body


10


idles. Thus, the ratchet wheel


20


may be rotated with the drive head


12


of the wrench body


10


to rotate counterclockwise only.




Accordingly, the ratchet wrench structure of the present invention has a simple construction, and may be processed easily. In addition, the ratchet wrench structure may be assembled and dismantled easily and conveniently. Further, the control spring


34


is secured on the pawl member


30


and retained by the control rod


42


, so that the control spring


34


may be positioned rigidly and stably without detachment.




While the preferred embodiment of the present invention has been shown and described, it will be apparent to those skilled in the art that various modifications may be made in the embodiment without departing from the spirit of the present invention. Such modifications are all within the scope of the present invention.



Claims
  • 1. A ratchet wrench structure, comprising: a wrench body, a ratchet wheel, a pawl member, and a control knob, wherein:the wrench body has a distal end formed with a drive head, the drive head of the wrench body has a first side formed with an operation space for receiving the ratchet wheel, and a second side formed with a control space for receiving the control knob, the drive head of the wrench body is formed with a connecting space connected between the operation space and the control space for receiving the pawl member; the ratchet wheel is mounted in the operation space of the drive head of the wrench body, and has an outer wall formed with multiple ratchet teeth; the pawl member is pivotally mounted in the connecting space of the drive head of the wrench body, and has a first side and a second side, the first side of the pawl member is formed with multiple engaging teeth detachably meshing with the ratchet teeth of the ratchet wheel, a control spring has a first end secured to a center of the second side of the pawl member, and a second end provided with a control ring that is extended into the control space of the drive head of the wrench body; and the control knob is rotatably mounted in the control space of the drive head of the wrench body, and has a side integrally formed or provided with a control lever for rotating the control knob, a control rod is eccentrically secured on a bottom of the control knob to rotate with the control knob, and is passed through the control ring of the control spring, for moving and displacing the control ring of the control spring.
  • 2. The ratchet wrench structure in accordance with claim 1, wherein the control space of the drive head of the wrench body has a wall formed with an annular snap groove, the control knob has a periphery formed with an annular retaining groove, and the ratchet wrench structure further comprises a retaining ring is secured between the retaining groove of the control knob and the snap groove of the control space of the drive head of the wrench body, for retaining the control knob in the control space of the drive head of the wrench body.
  • 3. The ratchet wrench structure in accordance with claim 2, wherein the retaining ring is substantially C-shaped.
  • 4. The ratchet wrench structure in accordance with claim 1, wherein the control lever of the control knob has a bottom formed with a receiving recess for receiving an urging spring and a positioning ball.
  • 5. The ratchet wrench structure in accordance with claim 4, wherein the wrench body is formed with multiple positioning holes located adjacent to the control space of the drive head of the wrench body, and the positioning ball may be moved by the control lever of the control knob to be detachably positioned in one of the multiple positioning holes of the wrench body, thereby providing a temporary positioning effect to the control lever of the control knob.
US Referenced Citations (2)
Number Name Date Kind
5957009 McCann Sep 1999 A
6164167 Chen Dec 2000 A