US 5,501,124 AGranted

Open end ratchet wrench

OwnerEarl T. Ashbyinventor

Life of this patent

Estimating the term…

Loading patent…

Abstract

An open end reversible ratchet wrench has only two pawls, only one of which is engaged with the ratchet at any one time. In a first embodiment, two multitooth pawls are pivoted on a common pivot pin. The design and spacing of the pawl teeth and the location of the pivot pin make it possible to use pawls with at least three and no more than four pawl teeth. For every rotational position of the jaw, at least one pawl tooth is engagable with the ratchet irregardless of the position of the slot. The pawls are biased towards engagement with the ratchet. A reversing switch operates a cam to select clockwise rotation of the jaw, counterclockwise rotation thereof or a neutral mode in which the jaw rotates freely without ratcheting to facilitate easy removable of the wrench. The position of the reversing switch is latched by a detent ball cooperating with locking notches on the casing. In a second embodiment, the pawls are pivoted on separate pivot pins on opposite sides of the head and extend crosswise to engage the rachet on the opposite side of the head. The selection means includes a pulley and cables to move the pawls to and from engagement with the rachet. In a third embodiment, a pair of pawls reciprocate along guide paths parallel to the longitudinal axle of the wrench.

Claims18

Dependent claims

An open end reversible wrench, comprising:

a head having an aperture;
an operating jaw journaled for rotation in said aperture, said jaw having a nut-engaging opening, a slot extending from said nut-engaging opening to the peripheral surface of said jaw, and a ratchet having a single row of generally rectangular ratchet teeth formed in said peripheral surface from one side of said slot to the other side thereof, said ratchet teeth having sides extending generally radially of said jaw, one side facing in the clockwise direction and the other side facing in the counterclockwise direction;
a pair of pivoted pawl means, one pawl means for allowing rotation of said jaw in a clockwise direction and for blocking rotation in a counterclockwise direction and the other pawl means for allowing rotation of said jaw in a clockwise direction and for blocking rotation in the counterclockwise direction, said pawl means each having a plurality of projecting pawl teeth having substantially the same pitch as said ratchet teeth, said one pawl means having pawl teeth with a blocking side which, when engaged with said ratchet, is parallel to and abuts the generally radial side of a said ratchet tooth facing in said counterclockwise direction, and said other pawl means having pawl teeth with a blocking side which, when engaged with said ratchet, is parallel to and abuts the generally radial side of a said ratchet tooth facing in said clockwise direction, each of said pawl means being so shaped and dimensioned and said pawl means being pivoted about a point so located that said pawl means engages said ratchet and releases from said ratchet without binding, each said pawl means having at least three and no more than four of said pawl teeth, and the span of said pawl means being sufficient that at least one of said pawl teeth is engagable with a ratchet tooth for every rotational position in said slot;
and
means for selectively engaging said one of said pawls with said single row of ratchet teeth for rotation of said jaw only in said clockwise direction or said other of said pawls with said single row of ratchet teeth for rotation of said jaw only in said counterclockwise direction, no more than a single pawl being engaged with said ratchet at any one time.

2 more elements

An open end reversible wrench, comprising:

a head having an aperture;
an operating jaw journaled for rotation in said aperture, said jaw having a nut-engaging opening, a slot extending from said nut-engaging opening to the peripheral surface of said jaw, and a ratchet having ratchet teeth formed in said peripheral surface from one side of said slot to the other side thereof;
a pair of pivoted pawl means, one for allowing rotation of said jaw in a clockwise direction and for blocking rotation in a counterclockwise direction and the other for allowing rotation of said jaw in a counterclockwise direction and for blocking rotation in a clockwise direction, said pawl means each having a plurality of projecting pawl teeth and each being pivoted on separate pivot pins on opposite sides of said head, said one pawl means being pivoted on a pivot pin on one side of said head and extending to and engagable with said ratchet on the other side of said head and said other pawl means being pivoted on a pivot pin on the other side of said head and extending to and engagable with said ratchet on the one side of said head;
and
means for selectively engaging said one of said pawl means with said ratchet teeth for rotation of said jaw only in said clockwise direction or said other of said pawl means with said ratchet teeth for rotation of said jaw only in said counterclockwise direction, no more than a single pawl means being engaged with said ratchet at any one time.

2 more elements

An open end reversible wrench, comprising:

a head having an aperture;
an operating jaw journaled for rotation in said aperture, said jaw having a nut-engaging opening, a slot extending from said nut-engaging opening to the peripheral surface of said jaw, and a ratchet having ratchet teeth formed in said peripheral surface from one side of said slot to the other side thereof;
a pair of pivoted ratchet pawls, one for allowing rotation of said jaw in a clockwise direction and for blocking rotation in a counterclockwise direction and the other for allowing rotation of said jaw in a counterclockwise direction and for blocking rotation in a clockwise direction, said ratchet pawls each having a plurality of projecting pawl teeth, said pawl teeth having substantially the same pitch as said ratchet teeth, said pawls being pivoted on separate pivot pins on opposite sides of said head, said one pawl being pivoted on a pivot pin on one side of said head and extending to and engagable with said ratchet on the other side of said jaw and said other pawl being pivoted on a pivot pin on the other side of said head and extending to and engagable with said ratchet on the one side of said jaw;
first and second bias springs, said first bias spring biasing said one pawl toward engagement with said ratchet on the other side of said jaw and said second spring biasing said other pawl toward engagement with said ratchet on the one side of said jaw;
and
means for selectively engaging said one of said pawls with said ratchet for rotation of said jaw in said clockwise direction or said other of said pawls with said ratchet for rotation of said jaw in said counterclockwise direction, no more than a single pawl being engaged with said ratchet at any one time, said means for engaging said pawls with said ratchet comprising pulley means having a first "clockwise" position for engaging said one pawl with said ratchet and for keeping said other pawl out of engagement with said ratchet, a second "neutral" position keeping both said pawls out of engagement with said ratchet, whereby said jaw may rotate freely without ratcheting to facilitate removal of said wrench, and a third "counterclockwise" position for engaging said other pawl into engagement with said ratchet and for keeping said one pawl out of engagement with said ratchet.

3 more elements

Dependencies are inferred from the claim text.

Facts

Application: 08/451,499Filed 26 May 1995 · division
Priority: 20 Apr 1992
Granted: 26 Mar 1996
Term ends: Not estimatedThe source records don’t support an estimate.

Classification3 codes

B25B 13/463
The ratchet parts engaging in a direction radial to the tool operating axis: a pawl engaging an externally toothed wheel
B25B 13/08
With rigid jaws: of open jaw type
B25B
Tools or bench devices not otherwise provided for, for fastening, connecting, disengaging