US3354755A

US3354755A - Adjustable wrench

Info

Publication number: US3354755A
Application number: US565634A
Authority: US
Inventors: Legrande John
Original assignee: Individual
Current assignee: Individual
Priority date: 1966-07-15
Filing date: 1966-07-15
Publication date: 1967-11-28
Anticipated expiration: 1984-11-28

Description

J. LEGRANDE Nov. 28, 1967 ADJUS TABLE WRENCH INVENTOR.

rand e HTTORNEY 2 Sheets-Sheet l Ja /70 [6y Filed July 15, 1966 NOV. 28, 1967 I J LEGRANDE 3,354,755

ADJUS TABLE WRENCH 2 Sheets-Sheet 2 Filed July 15, 1966 E [II Q INVENTOR. a $1 J/m' Zeyranc/e United States Patent 3,354,755 ADJUSTABLE WRENCH John Legrande, 419 Jackson Ave, Washington Township, Westwood, NJ. 07675 Filed July 15, 1966, Ser. No. 565,634 Claims. (Cl. 81314) ABSTRACT OF THE DISCLOSURE A wrench including an elongated member having a first jaw mounted on the member, a carriage slidably positioned on the elongated member, a second jaw mounted on the carriage and arranged in cooperative relation with the first jaw, the elongated member including a toothed rack bar, a hand grip lever pivotally mounted on the carriage, ratchet means pivotally supported by the carriage and the lever in an operative engagement with the teeth of the rack bar upon operation of the hand grip lever in a first operative range to cause a step by step actuation of the carriage and thereby the second jaw mounted thereon along the elongated member and toward the first jaw, the hand grip lever being so arranged in relation to the ratchet means as to cause the ratchet means to be positioned out of said operative engagement with the teeth of the rack bar upon operation of the hand grip lever in a second operative range so as to permit the carriage and thereby the second jaw to be freely positioned along the elongated member in relation to the first jaw, and other operator-operative means for effecting .a fine longitudinal adjustment of the position of the toothed rack bar in the elongated member in relation to the first jaw for effecting a corresponding minute adjustment in the position of the carriage and the second jaw relative to the first jaw upon the hand grip lever being operatively positioned in said first operative range with the ratchet means being in engagement with the toothed rack bar.

This invention relates to an adjustable wrench and more particularly to a wrench having a latching pawl and a ratchet operably engageable with a rack gear or bar upon movement of a hand grip lever in one sense to effect an extended movement of one jaw relative to the other jaw of the wrench in a primary vice grip adjustment, together with a secondary adjustment device for moving the rack bar in relation to the other jaw to elfect a fine adjustment of the vice grip relation of the jaws of the wrench on an object, and the latching pawl and ratchet being adjustable out of engaging relation with the rack bar upon movement of the hand lever in an opposite sense so as to permit free movement of the one jaw relative to the other jaw of the wrench.

An object of the invention is to provide an improved wrench having a spring biased pawl and ratchet operable by a hand grip lever into engagement with a rack bar upon movement of the lever in one sense to etfect movement of one jaw of the wrench relative to the other jaw a distance corresponding to that between two adjacent teeth of the rack bar or more teeth of the rack bar dependent upon the extent of movement of the hand grip lever.

Another object of the invention is to provide in a wrench of theaforenoted type a secondary adjustment for moving the rack bar relative to the other jaw to effect a fine adjustment of the relation of the jaws of the wrench upon the work.

Another object of the invention is to provide an operable arrangement of the spring biased pawl and ratchet in relation to the hand grip lever so that, upon movement of the lever in an opposite sense, the pawl and ratchet may be positioned out of engagement with the rack bar to 'ice permit free movement of the one jaw relative to the other jaw thereof.

Another object of the invention is to provide in an adjustable wrench a latching pawl pivotally mounted with a hand grip lever on a carriage for one jaw of the wrench and normally biased by a first spring supported by the carriage into engagement with a rack bar, and a driving pawl pivotally connected between the lever and a second link normally biased by a second spring supported by the carriage so as to position the driving pawl into an engaging relation with the rack bar, the hand lever being so arranged that upon pivotal movement thereof relative to the carriage, there is effected a rack bar engaging movement of the carriage on the handle of the wrench by the driving pawl to effect an actuation of the second link against the biasing force of the second spring and an adjustment of the one jaw relative to the other jaw of the wrench, while upon pivotal movement of the lever in an opposite sense the second spring may so actuate the driving pawl during a first increment of the movement of the hand grip lever as to position the driving pawl in a relation to the rack bar for subsequent rack bar engaging movement of the carriage, and said hand lever including releasable means effective upon an additional increment of movement of the hand lever in said opposite sense to engage said latching pawl in a sense to pivot the latching pawl against the biasing force of said first spring and out of engaging relation with the rack bar and such additional increment of movement of the hand lever positioning the driving pawl out of engaging relation with the rack bar subject to the biasing force of the second spring applied through the second link pivotally connected thereto so as to permit free slidable movement of the carriage relative to the rack bar for positioning one jaw of the wrench relative to the other jaw thereof.

A further object of the invention is to provide a microscrew adjustment in a free end of the handle of the wrench for effecting a fine adjustment of the rack bar in the handle of the wrench relative to the other jaw of the wrench and thereby a minute adjustment of the jaws of the wrench upon the work.

The above and other objects and features of the invention will appear more fully hereinafter from a consideration of the following description taken in connection with the accompanying drawings wherein one embodiment of the invention is illustrated by way of example.

In the drawings wherein like reference characters refer to like parts throughout the several views;

FIGURE 1 is a side elevational view of a wrench embodying the invention in which the jaw carriage and hand lever has been shown by solid lines in an operative position and by dash lines in a second extended position.

FIGURE 2 is a longitudinal sectional view of the wrench of FIGURE 1 with the hand lever in an operative position and the latching pawl and driving pawl shown biased by first and second spring elements into engagement with a rack gear.

FIGURE 3 is a fragmentary longitudinal sectional view of the wrench showing the hand lever adjusted in a sense to pivot the latching pawl against the biasing force of the first spring element and out of engaging relation with the rack gear while the driving pawl is shown positioned by the adjustment of the hand lever in said sense out of engaging relation with the rack gear so as to permit free slidable movement of the jaw carriage relative to the rack gear.

FIGURE 4 is a sectional view of the wrench of FIG- URE 2 taken along the lines 4-4 thereof, and looking in the direction of the arrows.

a FIGURE is a sectional View of the wrench of FIG- URE 2 taken along the lines 5-5 thereof and looking in the direction of the arrows.

Referring to the drawings and particularly to FIGURE 1, the wrench is shown as including an elongated metal channel member 10, having a U-shaped section, or an open side, as shownin FIGURES 4 and 5, with a fixed jam member 12 formed at one end of the elongated channel member and extending at a right angle thereto. The fixed jaw member 12 is adapted to cooperate with a complementary or companion movable jaw member 14 formed integrally with a carriage 16 and extending at right angles thereto. The jaw member 14 is slidably movable on the elongated channel member 10. The carriage 16, as shown best by FIGURES 4 and 5, has a U- shaped section which fits in a slidable relation on the U-shaped section of the elongated channel member 10. A round bolt 18 extends between opposite walls 19 and 21 of the carriage 16 and provides a bearing surface for the

end surfaces

20 and 22 of the U-shaped section of the elongated member 10 so that the carriage 16 may be slidably moved along the elongated member 10.

Further longitudinally adjustable in the U-shaped section of the elongated member 10 is a rack bar or gear '24, having a plurality of teeth 26 and an end biased by a spring 28. One end of the spring 28 is held by a bolt 29 while the opposite end of the spring 28 bears upon an adjacent end of the rack bar 24.

The spring 28 is held by the bolt 29 in a channel 31) extending through a portion of the jaw member 12 formed at one end of the elongated member 10 and into which channel 30 there also extends the end of the rack bar 24 positioned adjacent to the end of the spring 28 bearing thereon.

At the opposite end of the rack bar 24 there is a tooth 35, which abuts an end portion 37 of a secondary or micro adjustment screw 39, having a screw threaded portion engageable with internal screw threads 41 provided in an end portion 43 of the elongated member 10. At the outer end of the micro adjustment screw 39 there is provided a knurled portion 45, whereby the operator may readily turn the micro adjustment screw 39 to effect a fine inward or outward adjustment of the end portion 37. Thereupon the rack bar 24 biased by the spring 28 into abutting relation with the end portion 37, may be longitudinally adjusted in the U-shaped section of the member 10 by following the fine adjustment of the micro adjustment screw 39.

Further, asshown by FIGURE 2, there are arranged for operative engagement with the teeth 26 of the rack gear or ba1 24, a latching pawl 50 and a ratchet or driving pawl 52.

The latching pawl 50 is pivotally mounted on a pin 55, extending through the opposite walls 19 and 21 of the carriage 16, and the pawl 56 is further positioned on the pin 55 between

opposite walls

57 and 59 of a hand 1 lever 61, which is also pivotally mounted on the pin 55.

As shown by FIGURE 4-, a washer 63 is positioned on the pin 55 between the wall 19 of the carriage 16 and the wall 57 of the hand lever 61. A second washer 65 is positioned on the pin 55 between the wall 21 of the carriage 16 and the wall 59 of the hand lever 61.

The latching pawl 50 has an end portion 67 engaging one end of a spring 69, which has an opposite end seated in a recess'portion 71 of the movable jaw 14 of the carriage 16.

The spring 69, as shown by FIGURE 2, biases the latching pawl 50 in a counter clockwise direction about the pin 55 and an opposite toothed end portion 75 into a space between two adjacent teeth 25 of the rack bar 24 so as to lock the carriage 16 and the movable jaw 14 formed integrally therewith from slidable movement toward the right, as viewed in FIGURE 2, and away from the fixed jaw member 12 so long as the hand lever 61 remains in the position shown.

Slidable movement of the movable jaw 14 and the carriage 16 in an opposite direction toward the left, as viewed by FIGURE 2, may be effected by the operation of the ratchet or driving pawl 52. The driving pawl 52 is pivotally mounted at one end on a pin 80, which extends through the

opposite walls

57 and 59 of the hand lever 61 with a washer 82 being positioned on the pin between the driving pawl 52 and the wall 57, as shown by FIGURE 5. A portion 84 of the hand lever 61 connects the

walls

57 and 59, but at 86 there is provided an opening in the connecting portion 84 through which extends the end portion 67 of the latching pawl 50.

A pin 88 pivotally connects the opposite end of the driving pawl 52 to a link 90, having an adjustable bolt 92 extending from its end portion 91 of the link The adjustable bolt 92 has a head 93 and a screw threaded portion 94 engaged in internal threads formed in the aforesaid end portion 11 of the link 90.

A portion 95 of the bolt 92 intermediate the head 93 and the engaged screw threaded portion 94 is freely mounted in a slot 93 formed in a portion of the carriage 16 which connects the wall portions 19 and 21 thereof. A spring 102 is mounted on this intermediate portion 95 of the bolt 92 and is positioned between the end 91 of the link 90 and a washer 105 bearing on the portion 95 of the bolt 92. As shown by FIGURE 2, the spring 102 in the position shown biases the driving pawl 52 in a counter clockwise direction about the pin 80 so that an opposite end toothed portion is thereupon effectively biased by the spring 162 into a space between two adjacent teeth 26 of the rack bar 24.

It will be seen that, upon the toothed end portion 110 of the driving pawl 52 being initially placed in such position in a space between adjacent teeth 26 of the rack bar 24, and additional movement of the hand lever 61 in a counter clockwise direction about the pin 55 and toward the position shown in FIGURE 2 will act to bias the driving pawl 52 in a clockwise direction about the pin 8%. This will cause the end toothed portion 110 to bear against the adjacent surface of the rack tooth 26 immediately to the right thereof so as to effectively bias the carriage 16 and the movable jaw 14 in a sliding movement to the left and toward the jaw 12 along the elongated channel member 10 against the biasing force of the spring 69' acting through the latching pawl 50.

During this sliding movement of the carriage 16 to the left on the elongated member 10, the toothed end portion 75 of the latching pawl 50 will be biased by the adjacent surface of a rack tooth 26 immediately to the left thereof in a clockwise direction, as viewed in FIGURE 2, about the pin 55 and against the biasing force of spring 69 until the toothed portion 75 has been raised to the level of this rack tooth 2-6. Thereafter, upon a succeeding sliding movement of the carriage 16 to the left, the toothed portion 7 5 of the latching pawl 50 is biased under the force of the spring 69 into a space between the last mentioned rack tooth 2'6 and a next succeeding rack tooth 26 immediately to the left thereof.

The toothed end portion 75 is thereupon latched against the adjacent surface of the rack tooth 26 now immediately to the right thereof so as to prevent a reverse sliding movement of the carriage 16 to the right. The sliding movement of the carriage 16 to the left by the ratchet action of the driving pawl 52 in cooperation with the latching pawl 50 will continue until the hand lever 61 has been moved in a counter clockwise direction about the pin 55 to its extreme position, as shown by FIGURE 2.

Thereafter, upon movement of the hand lever 61 in a reverse clockwise direction about the pin 55 from the position shown by FIGURE 2 and within a limited arcuate operating range, the driving pawl 52 will be caused to move in a counter clockwise direction about the pin 80 and the toothed end portion 110 thereof under the biasing force of the spring 102 to bear upon the surface of an adjacent rack tooth 26 immediately to the left thereof until the toothed end portion 110 has been raised by the clockwise movement of the hand lever 61 to the level of this adjacent rack tooth 26.

Thereupon, the toothed end portion 110 of the driving pawl 52 will be biased under the force of the spring 102 into a space between the last mentioned rack tooth 26 and a next succeeding rack tooth 26 immediately to the left thereof to condition the driving pawl 52 for a suceceding driving action upon the hand lever -61 being once again moved in a counter clockwise direction, whereupon the ratchet action of the driving pawl 52 in cooperation with the latching pawl 50 will be efifected once again, as heretofore explained, to slidably position the carriage 16 and jaw 14 to the left.

When the

jaws

12 and 14 of the wrench are being positioned by the ratchet action effected by the operation of the hand lever 61 into a close proximity to a work object positioned therebetween, a further micro adjustment of the jaw 14 in relation to the jaw 12 and the work object may be readily effected by the operator adjusting the micro adjustment screw 39 through operation of the knurled portion 45. This, in turn, will cause a fine longitudinal adjustment of the rack bar 24 in the elongated member to effect a corresponding fine adjustment of the position of the carriage 16 thereon and the position of the jaw 14 in relation to the jaw 12 and work object positioned between the

jaws

12 and 14.

However, upon the hand lever 61 being positioned in a reverse clockwise direction to a position in excess of the limited arcuate operating range or to the extreme clockwise position shown by FIGURE 3, the portion 84 of the hand lever 6-1 connecting the

walls

57 and 59 thereof will engage the end portion 67 of the latching pawl 50 so as to bias the latching pawl 50 about the pin 55 in a clockwise direction against the biasing force of the spring 69. This action will in turn position the toothed end portion 75 of the latching pawl 50 out of engaging relation with the teeth of the rack bar 24 and cause the latching pawl 50 to follow the clockwise movement of the hand lever 61 in excess of the limited operating range.

Such clockwise movement of the hand lever 61 will also cause the toothed end portion 110 of the driving pawl 52 to be positioned out of engaging relation with the teeth 26 of the rack bar 24 and the driving pawl 52 to be biased about the pin 80 by the spring 102 to the extreme position, which is shown in FIGURE 3. Thus, at the extreme clockwise position of the hand lever 61, both the driving pawl '52 and the latching pawl 50 are effectively positioned out of engaging relation with the teeth 26 of the rack bar'24, as shown in FIGURE 3, so that the carriage 1'6 and jaw 14 may be freely moved along the elongated channel member 10 toward and away from the fixed jaw 12 to effect a rapid adjustment of the

jaws

12 and 14 in relation one to the other and to the work object which may be positioned therebetween.

It will be seen from the foregoing description that there is provided by my invention an adjustable wrench, including a latching pawl 50 pivotally mounted with a hand grip lever 61 by a pin 55 on a slidable carriage 16 for a slidable jaw14 of the wrench which is adjustably positioned in relation to a second fixed jaw 12 formed integrally with a handle 10. The latching pawl 50 is normally biased by a spring 69 supported by the slidable carriage 16 and into engaging relation with teeth 26 of a rack bar 24. There is further provided a driving pawl 52 pivotally mounted by a pin 80 on the hand lever 61 and pivotally connected by a pin88 to'a second link 90 normally biased by a second spring 102 supported by the carriage 16 so as to position the driving pawl 52 into an engaging relation with a tooth 26 of the rack bar 24. The hand lever 61 is so arranged that, upon pivotal movement thereof in one sense relative to the carriage 16, there is effected a rack bar 24 engaging movement of the carriage 16 on the handle 10 of the wrench by the driving pawl 52 in cooperation with the latching pawl 50 so as to etfect actuation of the second link 90 against the biasing force of the second spring 102 and a positioning of the slidable jaw 14 relative to the fixed jaw 12 of the Wrench. Furthermore, upon a pivotal movement of the hand lever 61 in an opposite sense, or clockwise direction as viewed in FIGURE 2, the second driving spring 102 may so actuate the driving pawl 52 during a first increment or operating range of movement of the hand lever 61 as to position the driving pawl 52 into an operative relation with a succeeding tooth 26 of the rack bar 24 for a subsequent engaging movement of the carriage 16 and jaw 14 carried thereby upon the hand lever 61 being moved in a reverse counter clockwise direction in the operating range. The hand lever 61 includes however, releasable means 84 which is rendered effective upon an additional increment of movement of the hand lever 61 in the clockwise direction and in excess of the operative range to engage the end portion 67 of the latching pawl 50 in a sense to pivot the latching pawl 50 on the pin 55 against the biasing force of the first spring 69 and out of engaging relation with the teeth 26 of the rack bar 24. Such additional increment of movement of the hand lever 61 in a clockwise direction to the position shown by FIGURE 3 is also effective to position the driving pawl 52 out of engaging relation with the rack bar 24 so as to permit a free sliding movement of the carriage 16 on the handle 10 for positioning the one sliding jaw 14 relative to the other fixed jaw 12 of the wrench. Furthermore, upon the hand lever 61 being adjusted into the operative range with the latching pawl 50 and the driving pawl 52 being in an engaging relation with teeth 26 of the rack bar 24, as shown for example by FIGURE 2, a micro screw adjustment 37-41 in the free end 43 of the handle 10 of the wrench may be rendered effective by appropriate adjustment of an operator-operative knurled portion 45 so as to effect a fine adjustment of the rack bar 24 in a longitudinal sense in the handle 10 of the wrench and relative to the other jaw 12 so as to cause a corresponding minute adjustment of the jaw 14 relative to the jaw 12 and the jaws 12-14 of the wrench relative to a work object that may be positioned therebetween.

Thus, the hand lever 61 through the foregoing novel arrangement eflFects the double function of providing the ratchet operation of the sliding jaw 14 relative to the fixed jaw 12 in a first range of operation, and the release of the latching pawl and driving pawl 52 from the teeth 26 of the rack bar 24 in a second range of operation of the hand lever 61 for permitting the free sliding movement of the carriage 16 and jaw 14 on the handle 10 of the wrench and relative to the other fixed jaw 12, while, in the first range of operation, the hand lever 61 in positioning the latching pawl 50 and driving pawl 52 into engaging relation with teeth 26 of the rack bar 24 further permits a micro adjustment of the jaw 14 relative to the jaw 12 and the work object therebetween by the operator making an appropriate adjustment of the knurled head 45 of the micro screw adjustment 37-41 in the free end 43 of the handle 10 of the wrench.

Although only one embodiment of the invention has been illustrated and described, various changes in the form and relative arrangements of the parts, which will now appear to those skilled in the art may be made without departing from the scope of the invention. Reference is, therefore, to be had to the appended claims for a definition of the limits of the invention.

What I claim is:

1. In a wrench of a type including an elongated member, a first jaw fixedly mounted on the member, a carriage slidably mounted on said member, a second jaw mounted on the carriage and arranged in cooperative relation with the first jaw, said elongated member including a toothed rack bar, an operating handle pivotally mounted on the carriage, ratchet means supported by the carriage and the handle in operative engagement with teeth of the toothed rack bar, the ratchet means being effective upon pivotal movement of the handle relative to the carriage to cause a step by step actuation of the earriage and thereby the second jaw mounted thereon along the member and toward the first jaw; the improvement comprising means for slidably mounting the toothed rack bar in the elongated member, and operator-operative micro adjustment means carried by the elongated member for effecting a fine longitudinal adjustment of the position of the toothed rack bar in the elongated member to cause corresponding minute adjustments in the position of the carriage and the second jaw along said member toward and away from said first jaw dependent upon the sense of the adjustment of the micro adjustment means.

2. The improvement defined by claim 1 in which said operator-operative micro adjustment means includes an adjustment member threadedly engaged in a free end of the elongated member and having an inner end portion operable to support one end of the rack bar in the elongated member, the elongated member having a channel at an opposite end for supporting the other end of the rack bar therein, a spring mounted in said channel and bearing upon said other end of the rack bar so as to bias the one end of the rack bar into engagement with the inner end portion of the adjustment member, the adjustment member having at an outer end thereof an operator-operative port-ion.

3. A wrench comprising an elongated member including a portion thereof having a first U shaped section with an open sided channel formed therein and arranged in an intermediate relation to opposite end portions of the elongated member, a first jaw provided at one end portion of the elongated member, a rack bar mounted in the open sided channel formed in the intermediate portion of the elongated member, the rack bar having a plurality of teeth exposed for operative engagement through the open side of said channel in the first U shaped section of the intermediate portion, a carriage having a second U shaped section mounted in slidable relation on the intermediate portion of the elongated member, a bearing member extending between opposite walls of the second U shaped section and providing a bearing surface for end surfaces of opposite walls of the first U shaped section so that the carriage may be slidably positioned along the intermediate portion of the elongated member, said carriage including a second jaw bodily movable with said carriage'toward and away from said first jaw, a hand grip lever, a latching pawl, a driving pawl, means pivotally mounting the hand grip lever and the latching pawl on the carriage, means pivotally mounting the driving pawl on the hand grip lever, the pawls having free ends engagable through said open side of the channel with teeth of said rack bar at longitudinally spaced points therealong, spring means supported by said carriage for resiliently holding the free ends of said pawls in coperating engagement with the teeth of said rack bar upon operation of the hand grip lever in one sense, and means rendered effective upon operation of the lever in another sense for positioning the free ends of the pawls out of said engagement with the teeth of the rack bar so as to permit said carriage and thereby the bearing member to be freely movable along the end surfaces of said opposite walls of the first U shaped section of the intermediate portion of the elongated member so that the second jaw may be freely positioned both toward and away from the first jaw.

4. A wrench comprising an elongated member, a first jaw provided at one end portion of the elongated member, said elongated member including a toothed rack bar, a carriage slidably mounted on an intermediate portion of the elongated member, a second jaw mounted on the carriage and arranged in cooperative relation with the first jaw, a hand grip lever, a latching pawl, a driving pawl, a single pin pivotally mounting both the hand grip lever and the latching pawl on the carriage, means pivotally mounting the driving pawl on the hand grip lever, the ,pawls having free ends engageable with teeth of said rack bar at longitudinally spaced points therealong, spring means supported by said carriage for resiliently holding the free ends of said pawls in cooperative engagement with the teeth of said rack bar, the hand grip lever being pivotally operative about the single pin and relative to the carriage in a first arcuate range to cause the driving pawl to effect a step-by-step actuation of the carriage and thereby the second jaw along the intermediate portion of the elongated member and toward the first jaw, the handgrip lever including a portion thereof to releasably engage the latching pawl, the hand grip lever being pivotally operative about the single pin and relative to the carriage in a second arcuate range to raise said portion ,of the lever to engage the latching pawl in opposition to the biasing force of said spring means to thereby withdraw the free end of said latchingpawl out of cooperating engagement with the teeth of said rack bar, the pivotal operation of the hand grip lever in said second arcuate range being further effective to so position the driving pawl under the biasing force of said spring means to withdraw the free end of the driving pawl out of the cooperating engagement with the teeth of said rack bar so as to permit said carriage and second jaw to be freely movable on the intermediate portion of the elongated member both toward and away from said first jaw.

5. The combination defined by claim 3 in which the means pivotally mounting the hand grip lever and the latching pawl on the carriage includes a single pin extending between the opposite walls of the second U shaped section for pivotally mounting both the hand grip lever and the latching pawl on the carriage, said spring means includes a first spring supported by said carriage for biasing said latching pawl to position the free end thereof in cooperating engagement with teeth of said rack bar, a second spring supported by said carriage for biasing said driving pawl to position the free end thereof in cooperating engagement with teeth of said rack bar, the hand grip lever being pivotally operative about the single pin and relative to the carriage in a first arcuate range to cause the driving pawl to effect a step-bystep actuation of the carriage and thereby the second jaw along the intermediate portion of the elongated member and toward the first jaw, the hand grip lever including a part thereof effective upon pivotal operation of the hand grip lever about the single pin and relative to the carriage in a second arcuate range to cause the latching pawl to be actuated in opposition to the biasing force of said first spring and out of cooperative engagement with the teeth of said rack bar while effectively positioning the driving pawl under the biasing force of said second spring out of cooperative engagement with the teeth of said rack bar so as to permit said carriage and said second jaw to be freely movable on the intermediate portion of the elongated member.

6. A wrench comprising an elongated member including a portion thereof having an open side-d channel formed therein and arranged in an intermediate relation to opposite end portions of the elongated member, a first jaw provided at one end portion of the elongated member, a rack bar mounted in the open sided channel formed in the intermediate portion of the elongated member, the rack bar having a plurality of teeth exposed for operative engagement through the open side of said channel, a carriage slidably mounted on the intermediate portion of the elongated member, said carriage including a second jaw bodily movable with said carriage toward and away from said first jaw, a hand grip lever, a latching pawl,-a driving pawl, means pivotally mounting the hand grip lever and the latching pawl on the carriage, means pivotally mounting the driving pawl on the hand grip lever, the pawls having free ends engageable through said open side of the channel with teeth of said rack bar at longitudinally spaced points therealong, resiliently holding the free ends of said pawls in cooperative engagement with the teeth of said rack bar, means for slidably mounting the rack bar in the elongated member, and operatoroperative micro adjustment means carried by the elongated member for effecting a fine longitudinal adjustment of the position of the rack bar in the open sided channel formed in the intermediate portion of the elongated member to cause a minute adjustment in the position of the carriage and the second jaw along said ember in relation to said first jaw in a direction dependent upon the adjustment of the micro adjustment means.

7. The combination defined by claim 6 in which the means for mounting the rack bar includes a channel in the one end portion of the elongated member for receiving in supporting relation one end of the rack bar, and the operator-operative micro adjustment means includes an adjustment member threadedly engaged in the opposite end portion of the elongated member, the adjustment member having an inner end portion extending into the open sided channel of the intermediate portion of the elongated member to support the other end of the rack bar, a spring mounted in the channel in the one end portion of the elongated member and bearing upon said One end of the rack bar so as to bias the other end or" the rack bar into engagement with the inner end portion of the adjustment member, and the adjustment member having at an outer end thereof an operator-operative portion.

8. The combination defined by claim including means for slidably mounting the rack bar in the elongated memher, and operator-operative micro adjustment means carried by the elongated member for elfecting a fine 1ongitudinal adjustment of the position of the rack bar in the open sided channel formed in the intermediate portion of the elongated member, and upon the hand grip lever being operatively positioned in the first arcuate range the adjustment of the position of the rack bar by the micr adjustment means causes a minute adjustment in the position of the carriage and the second jaw along said elongated member in relation to said first jaw in a di- 10 rection dependent upon the adjustment of the micro adjustment means.

9. The combination defined by claim 8 in which the means for mounting the rack bar includes a recess in the one end portion of the elongated member for receiving in supporting relation one end of the rack bar, and the operator-operative micro adjustment means includes an adjustment member threadedly engaged in the opposite end portion of the elongated member, the adjustment member having an inner end portion extending into the open sided channel of the intermediate portion of the elongated member to support the other end of the rack bar, a spring mounted in the recess and bearing upon said one end of the rack bar so as to bias the other end of the rack bar into engagement with the inner end portion of the adjustment member, and the adjustment member having at an outer end thereof an operator-operative portion.

10. The combination defined by claim 1 in which the operating handle includes means eifective to actuate the ratchet means out of operative engagement with the teeth of the rack bar upon a pivotal adjustment of the handle to an extreme arcuate position so as to render both the ratchet means and the micro adjustment means inelfective to position the carriage, and the carriage and the second jaw mounted thereon being thereupon freely slidable on the elongated member both toward and away from said first jaw.

References Cited UNITED STATES PATENTS 470,116 3/1892 Finsterer 254108 652,550 6/1900 Robinson 254108 1,249,587 12/1917 Auberg 81-31 X 1,783,827 12/1930 Carr 254108 OTHELL M. SIMPSON, Primary Examiner. WILLIAM FELDMAN, Examiner. G. WEIDENFELD, Assistant Examiner.

Claims

1. IN A WRENCH OF A TYPE INCLUDING AN ELONGATED MEMBER, A FIRST JAW FIXEDLY MOUNTED ON THE MEMBER, A CARRIAGE SLIDABY MOUNTED ON SAID MEMBER, A SECOND JAW MOUNTED ON THE CARRIAGE AND ARRANGED IN COOPERATIVE RELATION WITH THE FIRST JAW, SAID ELONGATED MEMBER INCLUDING A TOOTHED RACK BAR, AN OPERATING HANDLE PIVOTALLY MOUNTED ON THE CARRIAGE, RATCHET MEANS SUPPORTED BY THE CARRIAGE AND THE HANDLE IN OPERATIVE ENGAGEMENT WITH TEETH OF THE TOOTHED RACK BAR, THE RATCHET MEANS BEING EFFECTIVE UPON PIVOTAL MOVEMENT OF THE HANDLE RELATIVE TO THE CARRIAGE TO CAUSE A STEP BY STEP ACTUATION OF THE CARRIAGE AND THEREBY THE SECOND JAW MOUNTED THEREON ALONG THE MEMBER AND TOWARD THE FIRST JAW; THE IMPROVEMENT COMPRISING MEANS SLIDABLY MOUNTING THE TOOTHED RACK BAR IN THE ELONGATED MEMBER, AND OPERATOR-OPERATIVE MICRO ADJUSTMENT MEANS CARRIED BY THE ELONGATED MEMBER FOR EFFECTING A FINE LONGITUDINAL ADJUSTMENT OF THE POSITION OF THE TOOTHED RACK BAR IN THE ELONGATED MEMBER TO CAUSE CORRESPONDING MINUTE ADJUSTMENTS IN THE POSITION OF THE CARRIAGE AND THE SECOND JAW DEPENDENT UPON THE SENSE OF AND AWAY FROM SAID FIRST JAW DEPENDENT UPON THE SENSE OF THE ADJUSTMENT OF THE MICRO ADJUSTMENT MEANS.