HAND HELD GEARED WRENCH

TECHNICAL FIELD

This invention relates to gear operated wrench type tools driven at right angles, in general and more specifically to a wrench held by hand having a socket driven by a worm gear at an angular displacement through a universal jointed drive shaft.

BACKGROUND ART

In the past, prior art has developed tools that possess many desirable features of operation and utility, however, the technology at the time of development severely limited the methods of construc¬ tion and materials available.

Golding et al in U.S. Patent No. 1,273,774 teaches such a hand tool. They disclose a housing, gear wheel, worm gear, rotatable shaft, universal joint and a handle that allows the use of multiple sockets and is operated remotely while angularly displaced from the actuating plane. The housing is in two separate halves with the worm gear journaled between and a cavity for the gear wheel on each side. A separate cavity to receive the handle with its accompanying pivot pin is also disclosed. The handle is in line with the rotat- able shaft and contains an arm projecting from the side hingeably attached to the housing. The shaft is journaled within this handle and a hand crank is affixed at the end. No provision was made to

O PI

limit the angular movement of the head in relation to the handle.

United States Patent issued to Olinger No. 3,630,106 discloses a wrench having a shaft within a housing that rotates an integral worm gear. The sheet metal housing is formed as a wrapper and en- closes the gear and a retaining pin.

Schoeb in U.S. Patent No. 1,659,838 utilizes a hand crank and a pair of beveled gears, however, the angle of the shaft to the driven nut holding member is not adjustable. The crank arm is, however, removable from the rigid arm being rotatably attached to the gears with a universal joint.

Patent No. 1,477,448 issued to Roberts in the United States similarly employs a shaft having a worm gear rotated by a handle, however, no angular displacement of the head is taught and the shaft is in line with the worm gear. Booman discloses in U.S. Patent No. 1,016,607 a tool having independent handles both utilizing a joint, one swiveling, and the other a universal type. Bevel gears transmit the rotation of the handle to the enlarged head holding the tool, such as a screwdriver blade or twist drill. For background purposes and as indicative of the art to which the invention relates, reference may be made to U.S. Patent No's. 3,696,694 Boro Oct. 10, 1972 3,124,022 Corson Mar. 10, 1964 3,111,049 Brehmer Nov. 19, 1963 2,466,456 Lybyer April 5, 1949

DISCLOSURE OF THE INVENTION

In the past, hand tools have been made of forgings or cast- ings for many of the major working components. This type of con¬ struction requires grinding, machining, polishing, and plating, which is a costly and a labor intensive procedure. Further, materials have been improved over the years that allow greater strength and machinability. It is, therefore, the primary object of the inven- tion to improve the producibility of a hand held rotating gear wrench, such as taught by Golding et al , by making a single housing

with a simple stamped cover plate instead of two halves, as pre¬ viously utilized. Instead of positioning the worm gear in a journal between the two halves, separate removable self-lubricating bearings are utilized that are positioned in a cavity within the housing. The handle and shaft are separate structures being independent of each other combined with a stamped clamp holding them together. Instead of journaling the shaft inside of the handle, as previously used, a split sleeve bearing is disposed within each half of the clamp. Not only do these improvements reduce the cost, but the strength is increased using independent in line structures and the bearings increase the life by reducing wear and friction, also making the tool easier to operate.

An important object allows the handle to be immobile while the turning moment is remote from the working area. This is accomplished by attaching a secondary tool, such as a ratchet wrench, on the rotatable shaft arilowing one hand to hold the handle positioning the head over the workpiece while the other hand is free to rotate the shaft. A straight shaft extension allows an even greater flexibility to the tool and the extension may be used in conjunction with a universal joint typically found in a mechanic's tool box. With these combinations difficult or inaccessible areas may be serviced with ease and dispatch.

Another object is realized allowing this flexibility to prevent burns to the hands and arms of the user while working on hot parts of an engine. Further, cuts and abrasions may be prevented as only one hand need be placed into the confined area and the rotation is provided externally in a free space by the other hand.

The adaptation to use commercially available sockets is still another object. Industry standard 1/4, 3/8, 1/2 and 3/4 inch (6,35, 9.53, 12.7 and 19,1 millimeter) drive sockets may be employed connected directly upon the projecting square shank of the gear wheel. In particularly close or confined areas insert sockets may be used that have no projection at all beyond the head of the wrench. Yet another object provides an adjustable resistance to the angle of the head in relation to the handle. A thermoplastic com¬ pression rod places resistive pressure to the radial end of the

O PI

attaching arm allowing the arm to be angularly adjusted with the desired amount of force. This provides angular adjustment by hand, or if a fixed angle is desired, a simple screwdriver tensioning of the rod holds the head in place. Wear is also compensated for by this arrangement allowing the adjustment to be made from the end of the handle.

These and other objects and advantages of the present inven¬ tion will become apparent from the subsequent detailed description of the preferred embodiment and the appended claims taken in con- junction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a partial isometric view of the preferred embodi- ent with the keyed opening gear wheel in place less sockets.

FIG. 2 is a cross-sectional view of the preferred embodiment taken along lines 2-2 of FIG. 1.

FIG. 3 is a cross-sectional view of the handle and rotatable shaft taken along lines 3-3 of FIG. 1. FIG. 4 is a cross-sectional view of the handle and rotatable shaft retained within the clamp taken along lines 4-4 of FIG. 1.

FIG. 5 is a side view of the wrench with the handle adjusted at a slight angle.

FIG. 6 is a plan view of the preferred embodiment with areas cut-away to show the internal relationship of the elements. FIG. 7 is a side view of the preferred embodiment. FIG. 8 is a cross-sectional view taken along lines 8-8 of FIG. 6 with the square shanked gear wheel in place.

FIG. 9 is a cross-sectional view taken along lines 9-9 of FIG. 7 with the inside of the cavity depicted.

FIG. 10 is a partial isometric view of the gear wheel with the projecting square shank removed completely from the wrench for clarity.

FIG. 11 is a partial isometric view of the gear wheel with the keyed opening completely removed from the wrench for clarity.

FIG. 12 is a partial isometric view of an insert socket with

a small hexagonal opening removed completely from the wrench for clarity.

FIG. 13 is a partial isometric view of an insert socket as above with a twelve point arrangement to receive the head of a threaded fastener.

BEST MODE FOR CARRYING OUT THE INVENTION

Referring now in detail to the drawings and describing the preferred embodiment, the invention consists of a head 20 made of a housing having a cast metallic body 22 with a cavity 24 inside and an attaching arm 26 on one end. The body 22 is flat on both sides with a radial shape on one end and rectangular on the other with the arm 26 protruding from one side. The cavity 24 is formed with the open portion on the top side with basically the same shape as the periphery creating a relatively uniform wall thickness throughout. Protrusions do, however, occur in areas where the radial shape intersects with the rectangular, and some sections are cut-away to receive separate elements. The attaching arm 26 has a radial end with a bore in the center for attachment. A plurality of tapped holes 28 are located on the top surface for attaching a cover and are positioned near the corners and radially at right angles. A tapped hole with a fitting 42 for injecting lubricants is located on the rectangular end of the body 22, best illustrated in FIG. 1. The material of the body 22 is preferably cast or forged steel heat treated and stress relieved as required. A cover plate 32, the same shape as the body 22, is attached with threaded fasteners 34 to the tapped holes 28 in the body. This cover plate 32 is flat sheet metal, formed by stamping, with a hole in the center in line with the similar opening in the bottom of the body 22 and a plurality of holes are pierced that correspond in location with the tapped holes 28. The cover 32 may be easily separated from the body 22 with a hand tool, such as a screwdriver, or the like, by externally removing connecting threaded fasteners 34.

The inside cavity 24 and cover pl ate 32 define a chamber

-gTTREAl

which retains a gear wheel 36 and a worm gear 38. This combination of gears transfers rotation at right angles allowing the tool to be rotated at one end vertically transmitting this movement in a horizontal direction. The thickness of the tool is not much larger than the arm 26 itself.

A pair of bearings 40 are removably disposed within the body 22 and receive the worm gear 38 one on each end. These bearings 40 may be of the same configuration or different as a matter of choice, and maintain l near alignment of the worm gear 38, also providing a non-frictional rotating surface. The material may be an oil impregnated sintered metal, such as bronze, a thermoplatic substance such as teflon, or any other material having suitable characteristics for the application. The bearing 40 further contains a bore in the center that is larger in diameter than the shaft of the worm gear 38, allowing freedom of rotation and preventing wear by lubrication or the inherent characteristics of the base material itself. The gear wheel 36 is retained within this cavity through a register on each side rotatably penetrating the in line holes in the bottom of the body 22 and the cover plate 32. This relation- ship is best pictorially illustrated in FIG. 8, which is a cross- sectional view of the head 20. This gear interface and cavity section is lubricated with a grease on the intermeshed teeth of the gear wheel 36 and worm gear 38 applied by removal of the cover 32 or through a grease fitting 42 located in the rectangular end of the body 22, illustrated in FIGS. 1 and 7.

A bifurcated handle 44 having a fork on one end is _. pivotally connected to the head 20 on the arm 26. The fork 44 has a hole 46 through the middle of both forks through which a pin 48 is positioned. This allows the head 20 to rotate axially-within the forks to at least 180 degrees, 90 degrees in each direction from the centerline. This pin 48 has a tight fit on the forks of the handle 44 and a slip fit on the arm 26 allowing rotation without excessive play in the joint. Any type of pin 48 may be utilized, such as a rol.l pin, drive pin ^' , split pin, or even a threaded pin may be employed with ^' no effect upon the utility of the apparatus. The handle 44 con¬ tains a bore 50 through the entire length with the end opposite

"^JRΪ ,

the fork having a female thread. This bore 50 is in direct align¬ ment with the radial end of the arm 26 and as the radius is centered at the pin 48 the end of the arm 26 is always positioned away from the pin the same distance throughout the entire 180 degree travel of the head 20. The handle 44 is round, square, oval, or any shape practical with rectangular having a knurled surface being preferred. A resilient frictional compression rod 52 is loosely retained within this bore 50 and consists of a round rod with a threaded portion on one end with either a screwdriver slot, as illustrated in FIG. 6, or a hexagonal hole (not shown). The other end has an extended reduced diameter portion creating a shoulder. A separate tip 54 is round in shape with a concave end interfacing with the arm 26 and a recessed cavity on the other, the exact opposite of the rod 52. This tip 54 becomes an extension of the rod and is made of a resilient material of thermoplastic,.such as nylon, poly¬ styrene, polyethylene, polypropylene, acrylonitrile-butadiene- styrene, or the like. In another embodiment, not shown, the through bore is replaced by a round cavity with a spring loaded pin of the same material having the same overall utility, except is self- adjusting. It will be noted that in the preferred embodiment the rod 52 may be adjusted by rotating inward with a tool until the tension sets the angle of the head 20 permanently. This allows the tool to be prepositioned for hard to reach places with only the end of the handle needing manipulation. In normal operation the rod 52 simply applies sufficient pressure to controllably impede the axial movement of the body 20 in relation to the handle 44.

The worm gear 38 further contains an extension on one end, preferably in a square configuration protruding beyond the bearing 40 and the head 20. This square shank is receivably connected to a universal joint 56, well known in the art, allowing rotation while angularly displaced. This universal joint 56 is connected on the other end to a rotatable shaft 58 that is planar to the handle 44. The shaft 58 is round and of a length, including the universal joint 56, the same or slightly longer than the handle

44. The first end of the shaft 58 contains a socket that receivably

OMPI

connects to the universal joint 56, square being preferred, how¬ ever, a hexagonal shape will function with equal ease. The second end protrudes slightly beyond the handle 44 and has an external shape compatible with conventional hand tools, such as hexagonal or square. An internal opening of the same basic shape, except in reverse, allows similar tools to also be interfaced therein. With this arrangement an external tool may be connected, either on the outside or inside of the shaft 58, and rotated axially transmitting torque through the universal joint 56 to the worm gear 38. A dual function is included at the connection point on the second end, where extensions, ratchets, open or box end hand wrenches, adjust- • able spanners, or the like, may be utilized to rotate the wrench from this external location.

A clamp 60 attaches the handle 44 with the shaft 58. This clamp 60 is formed of sheet metal and is made in two pieces, a top and bottom, having the same configuration, except in mfrror image- As the handle 44 is preferably rectangular, the clamp 60 has a matching reversed shape on one side and a concave surface on the other to receive the shaft 58. A plurality of fasteners 62 in the form of capscrews, nuts, and washers connect the two halves of the clamp 60 together maintaining the structural integrity of the joint. FIG. 4 best depicts the relationship of the clamp 60 to the handle 44 and shaft 58. A split sleeve bearing 64 is interposed between the clamp 60 and the shaft 58 in the preferred embodiment. This bearing 64 has all the characteristics of a sleeve, except it is split longitudinally in half in order to be installed, as the shaft has raised portions on both ends. This bearing 64 is of a sintered oil impregnated bronze, -or a thermoplastic such as known by its registered trademark "TEFLON", or any other material having suitable anti-frictional characteristics.

In another embodiment the sleeve may be omitted with the shaft 58 simply journaled within the two halves of the clamp 60.

The gear wheel 36 may be in many and varied configurations as the utility of this invention is expanded to encompass types of threaded fasteners known in the art, such as screws, nuts,. bolts, fittings, etc., and even holes made by a twist drill or any workpiece

utilizing the rotary motion in a tight or cramped position. FIGS. 5-10 illustrates such a device with a projecting square shank 66 having a spring loaded detent pin on one of the flat surfaces that attachably receives a variety of sockets, also well known in the art. These sockets grasp the head of a fastener, such as a hexagon shaped capscrew, and one made in a set of conventional sizes in both the shank and internal hex. The gear wheel 36, or "worm gear" as it is sometimes called, is preferably a single thread type with a left hand thread, however, it may also be right handed according to the position of the top of the wrench. The mating worm gear 38, or simply "worm" as it is sometimes designated, is of the same style,, pitch, and pressure angle.

Another embodiment of the gear wheel 36 is pictorially illus¬ trated in FIG. 11 and consists of the same external teeth, however, with a keyed opening 68 in the center portion. This opening 68 is round with a plurality of female splines oppositely arranged on the inner surface, preferably four, as shown in FIGS. 1 and 11. A plurality of spring loaded detents 70 are positioned on the inner wall of the opening 68 between the keyways. These detents 70 are known in the art and have the utility of positioning mating parts therebetween.

Various sizes of insert sockets 72, illustrated in FIGS. 12 and 13, have a plurality of male splines on the periphery with in¬ dentations to receive the detents 70 of the gear wheel 36. These sockets 72 are slightly smaller in diameter and the width of the splines is narrower allowing a slideable fit into the gear wheel 36 described above. Each socket 72 contains a centrally located cavity 74 having an array of geometrically arranged points disposed in such a manner as to interface with the head of a threaded fastener, such as a hex head capscrew or nut. Any number and size sockets may be utilized with this hand held gear wrench and are usually supplied as sets with various internal sizes for hex or square configurations in the same manner as the external sockets previously described. In use the insert sockets are easily changed by pressing them into or out of the keyed opening 68.

The gear wheels 36, such as the type having the shank 66 or

OMPI

keyed opening 68, are interchanged by removing the fastening screws 34 in the body 22 and the cover 32, exposing them completely for removal and replacement.

With the cover 32 removed the entire assembly may be removed for replacement of any component, such as the worm gear 38 or bear¬ ings 40. This ease of dissembly allows all of the major elements to be replaced when worn or damaged. Further, the clamp fasteners 62 are removable exposing the sleeve bearings 64 around the shaft 58 when the clamp 60 is disconnected. In use the desired socket, either the conventional type or the internal socket 72, is selected and placed on or within the head 20 and the head is angularly adjusted. The threaded fastener on the workpiece is surrounded on the flat sides by the socket as held in place by one of the operators hands. A separate hand held tool, such as a ratchet wrench, is attached to the end of the shaft 58 and rotated by the operators other hand. This movement is trans¬ mitted rotatably through the shaft 58, universal joint 56, and worm gear 38. At this point the rotation is transferred angularly through 180 degrees to the gear wheel 36 which contains the above described socket.

While the invention has been described in complete detail and pictorially shown in the accompanying drawings, it is not to be limited to such details, since many changes and modifications may be in the invention without departing from the spirit and the scope thereof. Hence, it is described to cover any and all modifications and forms which may come within the language and scope of the appended claims.

O PI