US2537838A

US2537838A - Open end ratcheting wrench

Info

Publication number: US2537838A
Application number: US716906A
Authority: US
Inventors: George T Logan
Original assignee: Individual
Current assignee: Individual
Priority date: 1946-12-18
Filing date: 1946-12-18
Publication date: 1951-01-09
Anticipated expiration: 1968-01-09

Description

Jan. 9, 1951 G. T. LOGAN OPEN END RATCHETING WRENCH Filed Dec. 18, 1946 H y R M m W N /Z M A m w e m? 6 B final Patented Jan. 9, 1951 UNITED STATES PATENT OFFICE OPEN END RATCHETING WRENCH George Logan, New-Hope, Pa. Application December 18, 1946, .SerialN0. 716,906

18 Claims; 1

This invention relates to open-end ratcheting wrenches, and particularly the type intended for use with hexagonal nuts or bolt heads.

I have found that the wrenches heretofore available are not capable of use in many instances on the present day airplane and automotive vehicle because the installation renders the bolt or'nut' practically inaccessible. Not only is'the spaceavailable for turning a wrench extremely limited, but the clearance necessary to engage the jaws of a'wrencharound the nut or bolt head is likewiselimited, particularly on aircraft starters, generators, and the like;

The design of these parts prohibits the use of theordinary socket wrench because the-bolts or studs are recessed in the starter housing and the are through which an ordinary open-end wrench can be turned in such a location is so limited that the wrench" must be reversed'every time the nut is moved even an eighth of a turn orless. This condition alone has resulted in a great loss of time in servicing aircraft engines, an operation which under present conditions must be done with the greatest dispatch and efiiciency.

Furthermore, the ordinary open-end wrench having fixed jaws depends entirely upon the shape of the nut or bolt head for its turning action since'it has no gripping function. If the nut becomes worn or is slightly undersize, such a Wrench is useless. My invention contemplates a wrench having jaws which will grip the nut securely even though undersize or worn and in addition does not require removal and reversing.

In addition to the above advantages, I have found that many installations where tubing is used; for example in the refrigeration industry, require a special type of wrench to install the tube nuts. Such a wrench, when used on an assembly line in the mass production of refrigeration units or similar devices, must be capable of being inserted quickly around the tube nut and of quickly tightening the nut without slipping. By shortening such an operation only a few seconds on each installation, increased productive capacity amounting to a saving of thousands of dollars may be achieved.

A primary object .of the invention is to provide a ratcheting open-end wrench having pivoted jaws and a handle pivoted to one of the jaws in such a manner that a turning force. applied to the handle in one direction tends to close the jaws regardless of how the turning force may be applied.

A further object of the invention is to provide in a wrench of the type described an improved shape for the jaw teeth whereby ratcheting of the wrench is facilitated and slippage prevented.

A further object is to provide in'a wrench of the class described a' construction which limits the jaw opening'toprovid'e resilient opening for insertion over a nut, and locking action in all tangential opening of the jaws with respect to each other takes place.

A further object is to provide a spring loaded thumb release for holding the jaws'of a ratcheting open-end wrench in. an open or ratcheting position.

A further object is to provide a toggle clamping action in a ratcheting open-end wrench.

A still further object is to provide lever actuating means for toggle locked jaws in a ratcheting open-end wrench.

Further objects will'be apparent from the specifications and drawings, in which:

Fig. 1 is a plan view of my open-end ratcheting wrench. having a pair of notched pivoting jawsand ahandle pivoted on one of the jaws;

.Fig. 2. is a. slightly enlarged detail of the jaws showing. thelocation of thepivot pins with respect to the jaw teeth and the method of constructing my wrench; andv Fig. 3 shows the structure of Fig. 2 with the jaws in the open position.

I have found that extremely good results may be obtained in ratcheting open-end wrench having pivoted notched jaws by placing the jaw pivot pins in such a: position that turning force exerted on the wrench handle is applied to' close the jaws so that no independent force to maintain the jaws in this positionisnecessary. This result is achieved primarily through the shape of the jaws and the'location of the jaw teeth with respect to the pivot points for. the jaws.

In an open-end wrench adapted to be used on hexagonal nuts, I have found'that the maximum number of jaw teethwhich can be desirably.

used is four in each jaw. If more than this.

one jaw'and a nut or bolt head act asthe pivoting element and the other jaw acts as the"lim'i iting element. Wrenches having somewhat sim ilar action are described in my co-oending U. S.

Patent application Serial No. 68' .59l.

While certain novel features of the-inventionare disclosed hereinwith considerabledetailwitn respect to certain particular forms of the invention,.it is not desired to be limited to such details since many changes and modifications may be made, particularly with respect to the exact arrangement of the toggle members, without departure from the function of the invention in its broadest aspect.

Referring now more particularly to the drawings, upper jaw 5 has a forwardly extending curved portion 6 containing a plurality of grooves or notches l with curved sides 8 and an included angle of substantially 120. In a preferred embodiment, jaw 5 has four of such notches, the outermost notch 9, however, having only a partial side at 9. The innermost tooth II in jaw 5 is completely formed but no complete notch occurs at 2 since the exterior face of jaw 5 is cut away at this point. Jaw 5 extends rearwardly and has a pair of bifurcations 13 formed integrally with the jaw.

Lower jaw i i has a forward portion i5 carrying similar notches l and curved teeth 8. In

the preferred form, lower jaw H3 has three" notches l and three fully formed teeth 8', whereas a fourth and innermost tooth i6 is formed with a much smaller radius than teeth 8'. Jaw M has a thinned rearwardly extending portion ll adapted to fit between bifurcations [3 of upper jaw 5, and pinned thereto by means of pin i8. Recess [9 in the lower jaw accommodates helical spring 28 which abuts extension 2| of handle 22 and urges the lower jaw and the handle away from each other at this point. Handle 22 likewise has a thinned extension 23 adapted to be enclosed within bifurcations l3 and to be pivoted to the bifurcations by means of pin 2t. In the operative position, handie 22 (as seen in Fig. 2) can pivot clockwise on pin 24 until it contacts lever arm ll of jaw H1 at point 25. This pivoting motion is accentuated by spring Zil.

Shown by broken lines is a hexagonal nut or bolt head 26, which appears in two positions, the second of which is rotated 30 from the first position. For purposes of structure, the reference numeral 26 indicates a nut, but the composite outline of the nut in alternate 30 positions forms a 24-sided polygon with 120 interior angles at the points or corners lettered A to L consecutively, and 150 exterior angles alternately between the points (Fig. 2). The polygon A-L will be referred to hereinafter for purposes of iocating and laying out the construction lines for notches I, l" and pins l8 and 2d.

The pivoting movement of jaw 14 on pin 18 is limited in one direction by a shoulder 21? on jaw l4, and an outer edge 28 of bifurcations IS. The clearance between shoulder 2i and edge 28 is calculated so that a tight grip on a standard size nut 26 is obtained several degrees before shoulder 2'! contacts edge 28. Pivoting action of jaw M in the opposite direction is limited by contact with handle 22 at point in the closed position, or with handle 22 at point 29 in the open position (Fig. 3). The total opening of jaw 1 is such that ample clearance between the outer tips of the jaws is provided for insertion of the nut or bolt head 26. 7

As will more fully appear below, the relative length of portion 85 of jaw IQ with respect to portion H is such that the distance between the center 39 of pin is and contact point 25 is greater than the distance from pin center 30 to any notch or tooth i or 8 on portion i5. Similarly the distance between center 3i of pin 26 and point 25 is considerably less than any point on handle 22 to which turning force may be applied by an operai 4 tor. This construction provides a double mechanical advantage for actuating the jaws and consequently tight gripping of nut 26. Tightening of the jaws is obtained by rotating the entire wrench in a clockwise direction in Fig. 2. This action causes extreme gripping action on nut 26 due in part to the double mechanical advantage of the handle with respect to jaw 15, and also to the toggle action whichtakes place between the outer notches of jaw 5, particularly notch 9, inner notches of jaw I l and pin 18. It will be apparent that rotation of the wrench handle in a clockwise direction tends to rotate jaw l4 in a clockwise direction on pin l8. This provides a toggle gripping action which in ordinary circumstances would be ample to securely grip nut 26 without the additional expedient of pin 24 and rotatable handle 22.

In order that the foregoing toggle action oci cur, however, it is important that contact be made at all times between the teeth of both jaws and nut 25. Spring 28 performs this function, since it also urges jaw 14 to rotate in a clockwise direction on pin i8, regardless of the position of handle 22. I have found that the curved configuration of notches l and l materially aids the ratcheting of the wrench which takes place when handle 22 is turned in a counterclockwise direction. This movement causes the handle to pivot slightly on pin 24, thereby removing the point of contact between handle 22 and extension i? to a point such as 29, thus obtaining a limited opening clearance for jaw I 3 and jaw 5. The jaws may be held'in this open position by means of thumb pressure on extension I? in the event that it is desired to turn the wrench in either direction without gripping nut 25. I have found that a desirable radius for teeth 8 and 8' is .172 inch for a nut having a width off/ inch across its flats. It will be understood that the desired radius for the teeth will vary in accordance with the particular size of the wrench in question.

The construction and location of the pivot pins with respect to the teeth will now be explained. A 24-sided polygon, A, B, C, D, E, F, G, H, I, J, K, L, having a diameter corresponding to the size nut for which the wrench is to be designed, is first laid out. Assuming that the notches 1 in upper jaw 5 will contact apexes A, B, C and D of the polygon, it will be seen that this permits apex E to be unenclosed by a full notch in jaw 5, and apexes J, K and L to be entirely free from any contact with either jaw. A construction line is then drawn to connect apex B, the second notch from the outer extremity of jaw 5, with apex F, the apex of the polygon which precedes the first notch from the inner extremity of jaw M. A similar construction line is drawn to connect point J and point H of the polygon, the latter apex being the apex of the polygon which coincides with the first full notch from the outer extremity of lower jaw I4. Lines BF and JH will intersect at point at, thereby locating the center of pin 18. Apexes K and F of the polygon are then joined by construction line KB, and an arc, with the distance from pin center 39 to apex I of the polygon as a radius, is swung to intersect line KF at 3!, thus locating the center of pin 24. The desirable location for point 25 to insure that arm I? is longer than any contact point of jaw 14 with the nut, is obtained by swinging an arc, with point 30 as the center and the distance from point 36 to apex J as a radius, to intersect a line connecting apexes L and F of the polygon. The identical procedure may be uti- Arranalysis of this construction reveals that the. entire'nut is offset from the operative centerlin'e 32 of handle 22, and that. the center ofipin i8 is slightly below, in Fig. 2, a line connectingthe notch or u .or jaw 5 adjacent apex A-and the. notch in lower jaw i i adjacent apex This location of pin l8 insures a. toggle action of the jaws in clamping nut 28, regardless of which-3'0. degree position the nut .may assume in the teeth of the jaw. Furthermore, this location provides a minimum of relative jaw movementto efiectuate suflicient clearance in the jaws for easyinsertion of a nut, as well at ratcheting. This feature is clearly shown in Fig. 3.

Itis contemplated that the construction of my wrench is. readily adapted to various methods of manufacture,v since the jaws may be made by laminated stampings, or iorgings, as desired, and the extremely high gripping power or" the wrench permits an. operator to obtain excellent results in: close quarters with a relatively short wrench handle.

Having thus described my invention, I claim:

1. A ratcheting o en end wrench having a first jaw, a second jawpivoted to said first jaw, apivot pin for thefirstiand second jaws, and a plurality of notches in eachof said jaws adapted to grip a hexagonal element; the pivot pin being located, wheniithe jaws have closed on said hexagonal element, substantially at the intersection of a straightline passing through a first. and third apex: orthe hexagonal element, and straight line passing through a fourth and fifth apex of the hexagonal element; and in which the first apex-"of the hexagonalelernent is gripped by a second innermost notch on the upper jaw, and the fourth apex of the hexagonal element is grippedby an outermostnotch in the second jaw.

2. A ratcheting open end wrench having a first jaw, a second jaw pivoted to said first jaw, a pivotpin for the first and second jaws, and a plurality of notches in each of said jaws adapted to: grip a hexagonal element; the pivot pin being located, when the jaws have closed on said hexagonal element, substantially at the intersectionof a straight line passing through a first and-third apex of the hexagonal element, and a straight line passing through a fourth and fifth apex of the hexagonal element; and in which the-first jaw is provided with four notches and f'ourfullteeth, and the second jaw is provided with two-fullnotches and three full teeth.

3. A ratcheting open end wrench having a first jaw, asecond jaw pivoted to said first jaw, a pivot pin for the first and second jaws, anda plurality of notches in each of said jaws adapted to grip a hexagonal'element; the pivot pin being located,..when the jaws have closed on said hexagonal element, substantially at the intersection of a straightline passing through a first and third apex of the hexagonal element, and a straight line passing through a fourth and fifth apex of thehexagonal element; and in which the first jawis providedwithfour full notches and four full'teeth, the'second jaw is provided with two fullnotches and two full teeth, and the first apex of the hexagonal element is gripped by a second innermost notch'On the upper jaw and the fourth apex of the hexagonal element is gripped by an outermost notch in the second jaw.

4. Aratcheting open end wrench havinga first jaw, asecond'jaw pivoted to said first jaw, a pivot pin'forthe-first and'second jaws, a plurality of amaze-as:-

notchesinfeach .cf said jaws, said notches adapted tog-rip a hexagonal. element, a. handle pivoted: to; said firstajaw, and a pivot pinior said handleiandfirst jaw; the pivot-pin for. the jaws being; located,- when the-jawshave closed on said hexag-onalelement,. substantially at the intersection of a. straight line passing, through a first and third apex. oflthe. hexagonal element, anda straight line passing through a fourth and fifth apexof the; hexagonal element, and the pivot pin for th'erhandle. beingv located at theintersection of: a straight line passing through a third apex of thei:heXag0na1 element and the fifth apexofthe hexagonal element when said element is rotated 30 aboutits center in the direction of the apex numbers, and an arc. swung from the intersection of said jaw pivot pin locating lines and having; a radius substantially equal to the distance from said last named intersection to the fourth apex of the hexagonal element when said hexagonal element is rotated 30 in the direction of the apex numbers.

5. Aratchetingvopen end wrench in accordance. with claim 4 in which the second jaw is provided with a leverv to abut the handle, the point of: abutment between the handle and the lever in closed jaw position being spaced from the jaw pivot pin not less than the distance between thecenter of said jaw pivot pin and the fifthv apex of the hexagonal element;-

6. A ratcheting open end wrench in accordance with claim 4 having resilient means for urging the jaws into closed position.

'7. A ratcheting open end wren-chconstructed in accordance with claim 4 in which the notches are formed between curved teeth in the jaws.

8. A ratcheting open end wrench constructed. in accordance with claim 4 in which'the first apexof the hexagonal element is gripped by a. second innermost notch on the upper jaw, and the fourth apex of the hexagonal element is gripped by an outermost notch in thesecond jaw.

9. A ratcheting open end wrench constructed in accordance with claim 4 in which the first jaw is provided with four notches and four full teeth,

and the second jaw is provided with two full notches and three full teeth.

10. A ratcheting open end wrench constructed in accordance with claim 4 in which the first jaw is provided with four full notches and four, full teeth,vthe second jaw is provided with two full notches and two full teeth, and the first apex of the hexagonal element is gripped by a second innermost notch on the upper jaw and the fourth apex of the hexagonal element is gripped by an outermost notch in the second jaw.

11. A ratcheting open end wrench comprising afirst jaw having a plurality of curved teeth formin notches between said teeth, a bifurcated extension on said jaw, a second jaw having; a plurality of curved teeth forming 120 notchesbetween said teeth, said notches and teeth being adapted to grip a hexagonal element, an extension on said second jaw adapted to be enclosed within the bifurcations of the first jaw, a pivot for the jaws extending through the bifurcations and the second jaw, a handle pivoted between the bifurcations of the first jaw and abuttingthe extension. on the second jaw, and a pivot for said handle and first jaw; the pivot for the jawsbeing located when the jaws have closedon said hex-- agonal element, substantially at the intersection ofa straight line passing throughfirst and third apex of the hexagonal element and a straight line passingthrough a fourth and-fifthapexof the hexagonal element; and the handle pivot being located at the intersection of: a straight line passing through a third apex of the hexagonal element and the fifth apex of the hexagonal element when said element is rotated 30 about its center in the direction of the apex numbers, and an arc swung from the jaw pivot center and having a radius not less than the distance between said jaw pivot center and the fourth apex of the hexagonal element when said element is rotated 30 about its center in the direction of the apex numbers.

12. A ratcheting open end wrench constructed in accordance with claim 11 in which the first jaw is provided with four notches and four full teeth, and the second jaw is provided with two full notches and three full teeth.

13. A ratcheting open end wrench constructed in accordance with claim 11 in which the first jaw is provided with four full notches and four full teeth, the second jaw is provided with two full notches and two full teeth, and the first apex of the hexagonal element is gripped by a second innermost notch on the upper jaw and the fourth apex of the hexagonal element is gripped by an outermost notch in the second jaw.

14. In the design of a ratcheting open end wrench having a pair of notched pivoted jaws, the method of locating the relative positions of the jaw notches and pivot which comprises the steps of constructing an equilateral regular hexagon of the nut size for which the wrench is intended to be used, drawing a straight line between a first apex n the hexagon and a third consecutive apex on the hexagon, drawing a second straight line between the fourth consecutive apex on the hexagon and the fifth consecutive apex, extending said lines to intersect each other to determine the center of the pivot point for the jaws, forming a notch in one of the jaws at the first and second apexes of the hexagon, forming notches in said first jaw 30 on either side of said first apex, forming an intermediate notch in the second jaw at the third and fourth apexes of the hexagon, and forming a notch in the second jaw midway between said third and fourth notches.

15. In the design of a ratcheting open end wrench having a pair of notched jaws pivoted to each other, a pivot for the jaws, and a handle pivoted to one of said jaws, the method of locating the relative positions of said jaw notches, jaw pivot and handle pivot which comprises the steps of constructing an equilateral regular hexagon of the size'intended to be gripped by said jaws, locating the pivot center for the jaws substantially at the point of intersection between: a straight line connecting said first apex of the hexagon and the third apex of the hexagon, and a straight line connecting the fourth and fifth apexes of the hexagon, and locating the center of the pivot for the handle and one of said jaws substantially at the intersection between: a straight line connecting the third apex of the hexagon and the fifth apex of the hexagon when the hexagon is rotated 30 about its center in the direction of the apex numbers; and an arc swung from the jaw pivot center having a radius not less than the distance between said jaw pivot center and the fourth apex of the hexagonal element when said element is rotated 30 about its center in the direction of the apex numbers.

16. In the design of a ratchetin open end wrench having a pair of notched jaws pivoted to each other, a pivot for the jaws, a handle pivoted 8 to one of said jaws, and an abutment between one of the jaws and the handle, the method of locating the relative positions of said jaw notches, jaw pivot, handle pivot, and abutment which comprises the steps of constructing an equilateral regular hexagon of the size intended to be gripped by said jaws so that a first apex of the hexagon coincides with the position of the second innermost notch on the first jaw, locating the pivot center for the jaws substantially at the point of intersection between: the line connecting said first apex of the hexagon and the third apex of the hexagon, and a line connecting the fourth and fifth apexes of the hexagon; a line connecting the fourth and fifth apexes of the hexagon, and locatin the center of the pivot for the handle and one of said jaws substantially at the intersection between: a line connecting the third apex of the hexagon and the fifth apex of the hexagon when the hexagon is rotated 30 about its center in the direction of the apex numbers; and locating the point of abutment between one of said jaws and the handle substantially at the intersection between: a line connecting the third and sixth apexes of the hexagon and an are having a radius not less than the distance between said center and the fifth apex of the hexagon.

17. The method of locatingthe relative position of the jaw notches with respect to the jaw pivot in the upper jaw of a Wrench of the class described which comprises the steps of claim 14, rotating the hexagon 30 about its center in the direction of the apex numbers, locating the outermost notch in the upper jaw in a position coinciding with the sixth apex of the hexagon in the rotated position, locating the second innermost notch in the upper jaw in a position coinciding with the first apex of the hexagon in the original position, locating the third innermost notch in the upper jaw in a position coinciding with the first apex of the hexagon in the rotated position and locating the fourth notch in the upper jaw in a position coinciding with the second apex of the hexagon in the original position.

18. The method of locating the relative position of a plurality of jaw notches in the lower with respect to the jaw pivot in a wrench oi the class described which comprises the steps of claim 16, rotating the hexagon 30 about its center, locating the outermost notch in the lower jaw in a position coinciding with the fourth notch of the hexagon in the original position and locatlllg the second innermost notch on the lower jaw in a position coinciding with the third apex of the hexagon in the rotated position.

GEORGE T. LOGAN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 486,764 Carpenter Nov. 22, 1892 733,138 Bullard July 7, 1903 813,892 Hielscher et a1. Feb. 27, 1906 1,386,136 Sibbold Aug. 2, 1921 1,627,035 Jahn May 3, 1927 1,692,911 Vaughn Nov. 27, 1928 FGREIGN PATENTS Number Country Date 21,530 Great Britain Nov. 28, 1900 449,510 Germany Sept. 20, 1927