GB2327058A

GB2327058A - Ratchet wrench

Info

Publication number: GB2327058A
Application number: GB9714433A
Authority: GB
Inventors: Frank Mccann
Original assignee: Individual
Current assignee: Individual
Priority date: 1997-07-10
Filing date: 1997-07-10
Publication date: 1999-01-13
Anticipated expiration: 2017-07-10
Also published as: GB9714433D0; GB2327058B

Abstract

A ratchet wrench includes a head 11 having a slot for receiving a pawl 30. A driving member 20 and an actuator 46 are rotatably engaged in the head. A spring 44 is engaged in the actuator 46 and includes an arm 442 engaged in an aperture 32 of the pawl 30 for allowing the actuator 46 to rotate and to move the pawl to either of the narrower ends of the slot. The driving member 20 may be rotated by the head in one direction when the pawl is engaged in one of the narrower ends of the slot and may be rotated in a reverse direction when the pawl is engaged in the other narrower end.

Description

CONTROL MECHANISM FOR RATCHET WRENCH The invention relates to a ratchet wrench.

Typical ratchet wrenches comprise a driving member rotatably engaged in the head and including a number of teeth formed in the outer peripheral portion, a pawl pivotally secured in the head at a pivot shaft, and a knob for rotating the pawl and for allowing the pawl to control the rotational direction of the driving member.

However, the pawl may not be easily rotated such that the user have to rotate the pawl very hard.

According to the invention, there is provided a ratchet wrench comprising: a) a head including a slot having two narrower ends, b) a driving member rotatably engaged in the head and including a downward extending stud and including an outer peripheral surface having a plurality of teeth, c) an actuator rotatably engaged in the head and including an opening, d) a pawl slidably engaged in the slot of the head and adapted to be moved to either of the narrower ends of the slot, the pawl including at least one tooth for engaging with the teeth of the driving member, the pawl including a puncture, and e) a spring engaged in the opening of the actuator and including an arm engaged in the puncture of the pawl for allowing the actuator to rotate and to move the pawl to either of the narrower ends of the slot, the driving member being allowed to be rotated by the head in a first direction when the pawl is engaged in a first of the narrower ends of the slot, and the driving member being allowed to be rotated by the head in a reverse direction when the pawl is engaged in a second of the narrower ends of the slot.

The actuator includes a groove, the spring includes an extension engaged in the groove, the arm is extended from the extension.

In the drawings: FIG. 1 is an exploded view of a ratchet wrench; FIG. 2 is a cross sectional view of the ratchet wrench; and FIGS. 3 and 4 are bottom views illustrating the operation of the ratchet wrench, in which the cover plate is removed.

As shown in FIGS. 1-3, a ratchet wrench comprises a head 11 formed on one end of a handle 12 and having two holes 111, 112. A driving member 20 is rotatably engaged in the head 11 and aligned with the hole 111 and includes a number of teeth 21 formed in the outer peripheral surface. The driving member 20 includes a stud 22 extended downward for engaging with fasteners and having a spring biased projection 221 for engaging with and for retaining the fastener in place. A plunger 24 is engaged in the driving member 20 and a spring 23 is engaged between the driving member 20 and the plunger 24 for biasing the upper portion of the plunger 24 upward through the hole 111. The above described configuration is conventional for ratchet wrenches.

An actuator 46 is rotatably engaged in the head 11 and aligned with the hole 112 and includes a cut off portion 42 and includes an opening 43 for engaging with a spring 44 which includes an outward extended extension 441 and which includes an arm 442 extended upward from the extension 441. The actuator 46 includes a groove 45 for engaging with and for retaining the extension 441 of the spring 41 in place. The head 11 includes a slot 15 (FIGS. 3, 4) having two narrower ends and having a wider middle portion. A pawl 30 is engaged in the slot 15 of the head 11 for engaging with either of the narrower ends of the slot 15. The pawl 30 includes one or more teeth 31 for engaging with the teeth 21 of the driving member 20 and includes a puncture 32 for engaging with the arm 442 of the spring 44. A cover plate 50 is secured to the bottom of the head 11 by fastening screws 60 which are threadedly engaged with the screw holes 53 of the cover plate 50.

The cover plate 50 may secure the driving member 20 and the pawl 30 and the actuator 46 in place. The actuator 46 includes a hole 461 (FIG. 2) formed in the bottom for engaging with a spring 61 and a projection ball 62 which may be biased to engage with either of two depressions 51, 52 of the cover plate 50 for positioning the actuator 46 to the cover plate 50 and to the head 11. The actuator 46 includes a projection 47 extended upward for engaging with a recess 411 of a knob 41 which may be used for rotating the actuator 46 and thus for moving the pawl 30 to either of the two narrower ends of the slot 15.

In operation, when the pawl 30 is moved to one of the narrower ends of the slot 15 (FIG. 3) and when the handle 12 is rotated clockwise by a user, the driving member 20 may be rotated clockwise by the handle 12.

However, the driving member 20 may not be rotated counterclockwise by the pawl 30 and by the handle 12 when the handle 12 is rotated counterclockwise. As shown in FIG. 4, when the pawl 30 is moved to the other narrower end of the slot 15 and when the handle 12 is rotated counterclockwise, the driving member 20 may be rotated counterclockwise by the handle 12. However, the driving member 20 may not be rotated clockwise by the pawl 30 when the handle 12 is rotated clockwise.

The spring 44 only applies a small portion of the force against the pawl 30 such that the pawl 30 may be easily disengaged from the driving member 20 for allowing the pawl 30 to be easily moved relative to the driving member 20.

Claims

CLAIMS:

1. A ratchet wrench comprising a head including a slot having two narrower ends, a driving member rotatably engaged in the head and including a downward extending stud and an outer peripheral surface having a plurality of teeth, an actuator rotatably engaged in the head and including an opening, a pawl slidably engaged in the slot of the head and adapted to be moved to either of the narrower ends of the slot, the pawl including at least one tooth for engaging with the teeth of the driving member, the pawl including a puncture, and a spring engaged in the opening of the actuator and including an arm engaged in the puncture of the pawl for allowing the actuator to rotate and to move the pawl to either of the narrower ends of the slot, the driving member being allowed to be rotated by the head in a first direction when the pawl is engaged in a first of the narrower ends of the slot, and the driving member being allowed to be rotated by the head in a reverse direction when the pawl is engaged in a second of the narrower ends of the slot.

2. A ratchet wrench as claimed in claim 1, wherein the actuator includes a groove, the spring includes an extension engaged in the groove, the arm is extended from the extension.

3. A ratchet wrench substantially as hereinbefore described with reference to and as shown in the accompanying drawings.

3. A ratchet wrench substantially as herein described with reference to the accompanying drawings.

Amendments to the -fms have been filed as follows 1. A ratchet wrench comprising a head formed with a slot having a middle portion and two narrower end portions, a driving member rotatably mounted in the head and including a downwardly extending stud for engagement with a fastener, the driving member having an outer peripheral surface formed with a plurality of teeth, a pawl slidably mounted in the slot and arranged for movement to either of the two narrower ends of the slot on operation of a rotatable actuator, the pawl having at least one tooth for engagement with the teeth of the driving member and resilient connection means between the actuator and the pawl such that rotation of the actuator is effective to move the pawl to either of the two narrower end portions of the slot, the driving member being rotatable by the head in a first direction when the pawl is positioned at a first of the narrower ends of the slot and rotatable by the head in the reverse direction when the pawl is positioned at the second of the narrower ends of the slot, characterised in that the resilient connection means between the actuator and the pawl comprises a spring having a main body portion mounted in an opening in the actuator and including an arm which engages within an aperture in the pawl, which arm and aperture extend parallel to the teeth of the driving member.

2. A ratchet wrench as claimed in Claim 1, in which the spring arm is connected to the main body portion of the spring by an extension which is located in a groove in the actuator.