US2797600A - Ratchet type movable jaw wrench - Google Patents

Description

July 2, 1957 "B. K. BEAVER 2,797,600

RATCHET TYPE MOVABLE JAW WRENCH Filed Oct. 28, 1955 2 Sheets-Sheet l INVENTOR 500 K. BEAVER ATTORNEYS y 1957 B. K. BEAVER 2,797,600

RATCHET TYPE MOVABLE JAw WRENCH Filed Oct. 28, 1955 2 Sheets-Sheet 2 RA TOHE T FIG. 5

INVENTOR BUD K. BEAVER BY Smyrna & 5m

ATTORNEYS RATCHET TYPE MOVABLE JAW WRENCH Bud K. Beaver, Washington, D. C,

Application October 28, 1955, Serial No. 543,349

3 Claims, (Cl. 81-479) The present invention relates to torque-producing devices and more especially to wrench means for alternatively turning work, and ratcheting about same to recover working or gripping position. In the manufacture of slip-grip wrenches, great strides have been made to furnish the trade with a tool having the characteristics of simple ratcheting action and adequate gripping in confined areas, such for example .as in the maintenance of heavy engined vehicles, and water and air craft. Kisner, Lane, Yavner and Collard have made contributions in'this field, as evidenced by United States Patents Nos. 1,512,180, 2,697,372 and 2,592,781, and German Patent No. 220,348. A significant shortcoming in these patented and other prior devices, however resides in the inability of the user to initially engage threaded bolt head work with the wrench regardless of the disposition of such Work with respect to the confined area in which it is being received.

Most of the prior art devices cannot be applied initially to work unless the jaws are parallel to opposing fiat surfaces of the work.

In many ratchet wrenches of the prior art, an axial force is necessary to maintain the jaws of the device, both fixed and movable, fixed and fully engaged on opposed flat surfaces of the work, during working. It has been found that the magnitude of such undesirable axial forces must be directly proportional to the torque which is applied during the work. This is not only inconvenient, and often hazardous to the user, but reduces efficiency of the tool considerably. To overcome this deficiency, longer handles or levers are applied, thus restricting use of such ratchet wrenches within confined engine-compartment-like areas. In others having pivoting jaws, the ratcheting may be effected only through withdrawal of the wrench gripping surfaces a substantial distance from the axial center of the work. In certain ratcheting wrenches complex pawl locking means must engage a ratchet to effect a locking thereof and permit the user to apply torque to the work.

In operation of devices similar to theLane. construction, it is known that a component ratcheting-type force develops upon the movable jaw segment during ratcheting but is also present when one applies. torque to the work. This component force directs itself'rearwardly of the Wrench head and causes the movable jaw segment to retract. During non'ratcheting or torque producing stroke this component force tends to cause the movable jaw to retract, a most undesirable feature. If this component ratcheting force, on the other hand, could be applied to assist in holding the movable jaw against retraction, the feature would be desirable'in wrench con struction. By design this has been done in the present instance.

Broadly, the present invention maybe defined as a torque producing implement of the ratchet wrench type having opposed, flat jaws, the jaws being fixed and movable respectively, a support/ or shank for the movable nited States Patent M 2,797,600 Patented July 2, 1957 jaw resting in an arcuate recess within the head of the device for movement arcuately inwardly relative to the head during ratcheting and for jamming closure movement about the work during the anti-ratcheting or torqueproducing stroke. The device is particularly well adapted to work on tube fitting-s, yet is not limited to such coupling work, as in hydraulic, pneumatic, and electric conduit construction and maintenance.

It is an object of the invention to construct a ratchet wrench of the type having at least one movable jaw and wherein the working stresses are substantially evenly distributed throughout the fixed portions of the wrench head.

Another object of the invention resides in the provision of open end wrench means for efficiently working a turning moment on a bolt head and the like, wherein no turn-ing force is required other than normal lever force applied on the handle of the device.

Still another object resides in the production of a relatively simple wrench construction having fixed and movable jaws for alternately ratcheting and turing work, in which the movable jaw and adjacent fixed supporting portions are adapted to conform in action to the natural arcuate movement of the wrench by the operator to turn the Work, and in ratcheting to realign the jaws with respect to the work.

An advanced object of the invention is.to create a ratchet-type wrench in which the head and at least one movable jaw is designed to utilize component ratcheting forces during the application of torque to the work; whereby these forces are employed to seat the movable aw.

Another and important object of the invention is to provide a ratchet-type Wrench having fixed and movable jaws, and including means permitting arcuate movement of the movable jaw with respect to the fixed jaw for ratcheting action about a bolt head, and positive acting means for restoring the movable jaw to its original working position with respect to the fixed jaw.

A further object resides in the provision for simplified ratchet-type wrenches in which the 'head is offset, and whereby one or more jaws may be locked to facilitate turning where the swing of the wrench handle may be limited to 45 and even 30.

Ofsignificance is the fact that whereas the drawings depict preferred forms of invention, the concept of invention may be applied to varying types of torque producing implements. For instance, the principle of invention could be applied effectively to the removable head type wrench kit; to double end wrenches; to Stillson wrench combinations; to wrenches having heads which are adjustable with respect to the axis of the handle; screw wrenches; general utility construction wrenches; and alligator wrenches.

Other objects and advantages of the invention will be apparent from the following detailed description of ernbodiments of the invention, taken together with the accompanying drawings in which:

Fig. 1 is a force diagram depicting graphically the forces created when the present wrench is operatively associated with a Work piece;

Fig. 2 is a plan view, parts thereof being broken away, of one embodiment of the invention utilizing manual movable jaw positioning means;

'Fig. 3 is a view in perspective of a modified wrench construction in accordance with the invention, a cover portion of the head of the wrench being in phantom detail to. exposethe movable jaw retaining channel pot tion' of the head;

Fig. 4 is a view in side elevation of the wrench of Fig.8 the cover portion of the head thereof being broken away to reveal the disposition of the movable jaw with respect to the head during slippage of the wrench head about the work;

Fig. 5 is a view in side elevation of an offset modifica tion of inventive concept revealing pawl means for locking a movable jaw construction in fixed relation to the permanently fixed and opposed jaw, and

Fig. 6 is a fragmentary plan view of a further medi fication having a mechanical lever jaw return system.

In Fig. 2 of the drawings, there is shown a Wrench embodying the principles of the present invention and utilizing manual means for restoring the movable jaw from ratcheting position to work-engaging position. A ratchet type wrench generally designated 10 has a handle or lever portion 12 and a head portion 14 secured to the handle.

The principal elements of the head comprise: fixed jaw 16 and movable jaw 18 having a shank which is slidably retained in an arcuate cavity 20. The faces of the respective jaws are preferably diametrically opposed and flat. The fixed head includes a body portion 22 integrally associated with the fixed jaw 16. The cavity 20 extends substantially arcuately from a point adjacent the fixed jaw 16 of the head through the portion 22 and opens out of the head as seen in the drawings. The arcuate cavity 20 includes an enlarged chamber 24 and extending therefrom an arcuate portion 26 which constitutes a bearing surface for the movable jaw 18. While in the drawing the portion 26 is shown as an offset continuance to the portion 24 such a construction is not necessary as will be better understood from the following description.

A longitudinally extending channel 28 extends through a portion of the body of handle 12 and opens into the chamber 24 at its forward end. At the other end of the channel 28 there is an offset channel 30 opening into an inset recess 32 in a lateral edge of the handle 12. A lever 34 is pivotally mounted in the channel 28 by means of pivot 36 and having a handle portion 38 of a size and shape to fit into inset recess 32 when in depressed position as will appear hereinafter. At the for ward end of lever 34 a head or knob 40 is provided for contact and coaction with the inner or rearward face of movable jaw member 13.

The movable jaw 18 in this embodiment is shown as having an offset shoulder 42 for coacting with shoulder 44 interconnecting chamber 24 and arcuate portion 26 of the arcuate cavity 20. Coaction between offset shoulder 42 and shoulder 44 will, as is apparent from the drawing, serve to limit outward extension of the movable jaw beyond its intended Working relation with the fixed jaw. A cover 46, fragmentarily shown in the draw ing for purposes of clarity, covers the entire side of the wrench including the handle 12 and head 14. This cover forms with the longitudinal channel 28 a closed channel and coacts with the arcuate cavity 20 to form a generally boxed or rectangular shaped channel in which the movable jaw 18 is restricted and slidably mounted.

In operation, this embodiment of the invention acts so that the respective fixed and movable jaws continuously engage the fiat surface of the work, here represented as a bolt head or nut, regardless of the fact that the device may initially slidably engage opposed vertices of the head of the work as shown in the drawings. When the wrench has been placed on the work piece and is turned in the direction of the lock arrow in Fig. 2 to rotate the work piece, the hand of the operator Will press against the handle portion 38 thereby pivoting the lever 34 and moving the movable jaw 18 into parallel relationship with respect to fixed jaw 16. Upon continued turning of the wrench handle in this direc tion, the movable jaw 18 will jam with respect to arcuate portion 26 and will transmit the torque to the Work piece and rotate the same. When the wrench handle is turned in the opposite or ratcheting direction the hand of the operator will be against that side of the handle opposite handle portion 38 and due to the forces exerted on the movable jaw, this movable jaw will slide into retracted position in arcuate cavity 20 and will freely ratchet around the work piece. In other words, unless the handle portion 38 is depressed to initially return the movable jaw 18 to its working position the wrench can be freely ratcheted around the work piece or inserted at any angle onto the work piece. Manifestly, if it is desired to reverse the direction of rotation of the work piece, the wrench is merely turned onto its opposite side.

In the embodiment shown in Fig. 3, represents a ratchet-type wrench having a handle or lever portion 112 and head portion 114 secured to said handle.

The principal elements of the head comprise: fixed jaw 116 and movable jaw 130, said movable jaw being retained by the head 114 substantially as shown and described hereinafter. The faces of the respective jaws are preferably diametrically opposed and flat. In this construction, the fixed head includes a body portion 118 integrally associated with the fixed jaw 116. A recessed portion 120 of the head serves to support a cover member hereinafter described. There is additionally, a cavity 122 extending substantially arcuately from a point adjacent the fixed jaw 116 on the head through the portion 118. It will be appreciated that when a cover is fitted into the recess 120 of the wrench head, the cover. together with the cavity 122, forms a generally boxed or rectangular shaped channel. One portion of the channel designated 124, is adapted to hold resilient compression means 150 limitedly confined. In offset continuance of the portion 124 of the cavity there is an arcuate portion 126 which serves as a bearing surface for the movable jaw member 130. In practice, however, this oifset is not necessary inasmuch as different means may be employed to limit movement of the movable jaw. Dividing and interconnecting the respective cavity portions 124 and 126 is an offset shoulder 128 serving to limit outward extension of the movable jaw beyond its intended working relation with the fixed jaw by coaction with shoulder 142 on movable jaw 130.

Movable jaw 130 also includes an arcuate shank portion 132, a head 134, gripping face 136 of head 134 and an abutment portion 138 extending laterally to either side of the shank 132 for restricting rearward movement of the movable jaw as through contact with related extremities 144 of the head.

It will be apparent from Figs. 3 and 4 that the movable jaw is constantly urged into parallel working relation with respect to the fixed jaw as by the action of compression element 150 against the free end 140 of the movable jaw. Limiting the movement of the movable jaw is, of course, contiguous contact made by shoulder extension 142 of the movable jaw with the abutment 128 formed within the head.

Cover means 146 conforms substantially to the fixed head and in design may be secured within the recess 120 of the head by any suitable means: riveting, spot welding, or by machine screws.

The modification shown in Fig. 5 includes handle or lever 212 having secured thereto a head 214, said head comprising a fixed jaw 216 and a movable jaw 239. The body portion of the head defines, as in the basic construc tion, means for retaining a cover as at 220, a suitable milled or molded recess 222 for the movable jaw and accompanying parts; said recess being further defined as including a portion 224 for the compression element and free end of the movable jaw and a portion 226 forming with a cover element a channel for the shank portion 232 of the movable jaw. In this innovation, converging movement of the movable jaw is limited by abutment of the shoulder portion 242 thereof with a corresponding projection 228 of the head. Ratcheting-type movement of the movable jaw 230 is limited in the present construction as by abutment of the free end 240 with a suitable wall segment within the recess 224 as at 225. Moreover, there is provided, cavity 227 suitable for rotatably confining a pawl construction hereinafter defined.

The pawl assembly 260 comprises a selection lever 262, pivot pin 26,4 and pawl 266. The pawl assembly 260 may be set within the head as by cap screw means retained to. the cover or alternately retained in a suitable well within the head bearing atop the cover itself. The pawl may be swung into engagement or disengagement with a stud on the shank of jaw 230 as desired. In the present con.- struction, it is noteworthy that the head of the device is offset substantially with respect to the axis of the handle.

The operation of the devices shown in Figs. 3, 4 and 5 may be defined substantialy as follows: In gripping the work as in Fig. 2, the respective fixed and movable jaws of the device are adapted to continuously engage the flat surface; of the work regardless of the fact that the device may initially slidably engage opposed vertices of the head of the work as shown in Fig. 4. Referring to Fig. 3, it will'be noted that to eifect counterclockwise torque or turningstrain the movable jaw must be set or fixed by means of shank 132 within recess 126 of the head. In elfecting such turning, it has been found that the working torque moment upon the lowermost jaw is applied substantially at the rear thereof.

Reference is now made to Fig. l of the drawings to set forth the; principle of operation of the device. One of the features inherent in the invention is, the fact that it, will alternately ratchet (R) or lock (L), depending solely upon the direction of rotation imparted to the handle by the operator.

Assume for the moment that the device is oriented about the work as shown, that finite clearance exists between the work and the jaw flats, and all sliding parts are frictionless. Then:

(a) During clockwise rotation of the handle, the forces exerted by the work on the jaw flats may be represented by the vectors Rm as shown in Fig. 1. If the virtual center of rotation of the movable jaw is located to the right of the line ad, say at point 0, the movable jaw will be urged to rotate counter-clockwise (ratchet) by a moment of magnitude RrX.

(b) During counter-clockwise rotation of the handle, the ratcheting forces Rr,2 disappear and are replaced by the locking forces Lr,2. Again, these are forces which are exerted by the work on the jaw flats. With the virtual center of rotation of the movable jaw located to the left of the line b-c, the movable jaw is urged to rotate clockwise by a moment of magnitude Lry. This moment will increase in magnitude in direct proportion to the force exerted on the handle by the operator, tending to increase the jamming action of the movable jaw against the work.

The forces referred to and as shown in the diagram are correct for frictionless operation. Under actual working conditions however, friction will exist. This friction actually results in better locking operation and gives increased action to resist rotation or opening movement of the movable jaw. The resultant of force LI, and the friction force perpendicular thereto along line c-d in the direction of d is a vector force canted forwardly and giving a greater moment arm 0-y.

Virtually no axial thrust along the handle of the device is required to maintain the device in Working relation with respect to the threaded member or work acted upon. The natural tendency for the movable jaw to converge with the fixed jaw upon the work immediately preceding the application of torque insures its parallel relation with respect to the fixed jaw and during operation, the frictional locking of the respective contiguous surfaces of the movable jawshank and wall 126 of the head insures an additional positive and immovable grip upon the work so long as torque is applied thereto.

In returning or releasing the device from torqueing to recovery for further turning, the wrench head is retained equi-distant from. the center axis of the work. In ratcheting, component forces of ratcheting strike the forward portion of the face of the movable jaw downwardly and substantially in line'with the general contour of the socalled ratcheting or recovery turn, thereby causing the shank of the movable jaw to slide within the channel defined between cover and within the head, compressing the compression member 150. It is noteworthy that the contour of the arcuate non-gripping face of the head is designed to permit the vertices of the work to ride in contact therewith during the ratcheting movement. This minimizes operation space requirements. a This feature is especially valuable particularly where the individual works the coupling instrument in close quarters. To recapitulate, the wrench remains equi-distant from the center of work irrespective of the direction of turn, and irrespective of whether the action is working or releasing, as in ratcheting. 1

Now with respect to the operation of the device shown in Fig. 5, the modification is designed to permit operation of the wrench on a hexagon nut where the swing of the handle may be limited to less than 60. In this innovation,'one, can move the selectivity lever 262 to ratchet position whereby there is obtained substantially the same effect as in the aforementioned devices. However, in close qu'arteroperation, as where one has lessthan a 60 swing, one reverses the selectivity lever from ratchet to lock to deactivate the ratchet mechanism. Now one may turn the wrench over for complementary close quarter work, thus enabling the user to continue turning the work. This process may be repeated until the job is finished.

Fig. 6 shows a further modification wherein a mechanical lever jaw return system is provided. The handle 310 has the wrench head 312 as in the other modifications and includes a fixed jaw 314 and a movable jaw 316. Movable jaw 316 is slidably mounted in arcuate recess 318. A continuance of the recess is provided at 320 which is enlarged and an offset shoulder 322 is between the recesses. Movable jaw 316 has a shoulder 324 for coacting with offset shoulder 322 to limit outward movement of the movable jaw.

A lever 326 is pivoted on movable jaw 316 at 328. A second lever 330 is pivotally secured to the free end of lever 326 at 332. The opposite end of lever 330 has a nose portion 334, behind which it is pivotally secured to fixed jaw 314 at 336. These levers constitute a mechanical jaw return system as will be explained in detail hereinafter.

The full line showing of the movable jaw, levers and bolt head 338, or the like, is the working arrangement or position of the wrench. The dotted line showing is the ratcheting position.

Counterclockwise movement of the wrench handle as shown in the drawing is the torqueing direction and the operation is the same as in the other embodiments. When ratcheting, the corner of the hexagonal bolt in the throat of the wrench will move up along the throat toward the stationary or fixed jaw. After passing the maximum required open jaw position the wrench faces are still not on the next succeeding set of bolt faces. The extension of nose 334 then starts to engage the bolt head. Approximately the last one-eighth of a 60 turn (7%) of the wrench is utilized to engage the extension and return the movable jaw to working or jamming position.

it is to be noted that in this form of the invention as in all of the other forms, the design geometry of the head closely approximates the head design of conventional open end wrenches of the non-ratcheting type and the movable jaw actuates within this overall geometry. This is very important where limited space requirements and actuating room must be considered and where ratcheting is to take place the wrenches must conform to these requirements.

From the foregoing, it will be apparent that the movable jaw of the invention is a wholly movable element, considering that portion which is work engaging as the jaw, and can be defined additionally as that portion which extends outwardly from the throat area of the head. The same is true of the fixed jaw, in that it is the portion which extends outwardly from the throat area consisting of the curved work engaging extremity of the head between the jaws. It is this construction which provides the variable work-entrance opening and permits approach of the work at any angular disposition of the jaws with respect to the work.

Whereas the aforementioned invention has been defined with particular reference to its use on hexagonal bolts and the like, and whereas the drawings depict fixed heads on fixed handles, it should be obvious to those skilled in the art that various modifications in and to the invention may be constructed without departing from the spirit of the invention as defined in the appended claims. Various spring means may be employed to facilitate the ratcheting of the wrench; for instance, the inventive concept includes the use of leaf spring and related mechanisms.

The location and construction of such means is not limited to that shown in the drawings.

I claim:

1. A ratchet type movable jaw wrench including a head, a fixed jaw on said head, a wholly movable jaw on said head, all portions of said movable jaw extending from said head, said fixed jaw and said movable jaw defining therebetween a variable size work entrance open mg. I

2. A ratchet type movable jaw wrench as claimed in claim 1, said movable jaw having a curvilinear shank portion, an arcuate channel defined within said head providing a bearing and seat for said shank portion, said shank portion being slidably arcuately mounted in said arcuate channel.

3. A ratchet type movable jaw wrench as claimed in claim 1, and including pawl means selectively engageable with said movable jaw to lock it in working position with respect to said fixed jaw.

References Cited in the file of this patent UNITED STATES PATENTS 733,525 Worden July 14, 1903 810,304 Remion Jan. 16, 1906 1,308,440 Morrison July 1, 1919 1,320,668 Askman Nov. 4, 1919 1,444,216 Sorensen Feb. 6, 1923 1,512,180 Kisner Oct. 21, 1924 2,386,444 De Graw Oct. 9, 1945 2,565,154 Wedvik Aug. 21, 1951 2,731,866 Erickson Jan. 24, 1956 FOREIGN PATENTS 220,248 Germany Mar. 23, 1910 268,643 Germany Dec. 23, 1913 514,510 France Nov. 16, 1920

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