Abstract:
An adjustable crowfoot device removably attachable to an extension device, for gripping and either loosening or tightening an object in response to a turning motion of the extension device, and having a fixed claw member with a pinion receiving hole, an adjustable claw member, rack and pinion for slidably connecting the adjustable claw member to the fixed claw member where the pinion is rotatably connected within the pinion receiving hole and where the adjustable claw member has a rack having teeth connected to the pinion such that the teeth extend away from the flat surface between the two flat surfaces of the claw so as to provide a continuity of mating area.

Description:
This application claims the benefit of U.S. Provisional Application No.60/107,669 filed Nov. 9, 1998. 
    
    
     BACKGROUND OF INVENTION 
     This invention relates to the field of hand tools, in particular a crowfoot. A crowfoot is a descriptive name used for a fixed-jaw, offset tool for tightening and loosening nuts, bolts and fittings in tight places. It is utilized by expert craftsmen to reach into inaccessible regions of heavy equipment and machinery, for example, where hex fittings, nuts and bolts, etc. are both difficult to reach and difficult to maneuver a tool around. In these situations, access is typically limited to utilizing an elongated rigid handle member (extension), to which there is removably attached a variation of sizes of fixed-jaw crowfeet. The craftsman simply selects out of his or her toolbox the appropriate metric or standard-sized crowfoot for the anticipated need, attaches it to the end of the elongated handle, inserts the handle and crowfoot attachment deep down into the machinery where needed, and twists and turns as necessary to loosen or tighten the respective nut, bolt or fitting. 
     This has several disadvantages and deficiencies. In particular, it requires an unusually high and burdensome number of tools inasmuch as a separate crowfoot is needed for each size of nut, bolt, or fitting available, in both metric and standard sizes. If one is working on an engine locomotive, an airplane engine or heavy sophisticated machinery of any kind, in house or in the field, there is a need for a single adjustable crowfoot that is not only relatively compact so as to fit in tight places while retaining its adjustable features, but is also easy to maneuver in tight places so that it is not only easy to turn while maximizing the force needed, but is somewhat self-adjusting so as to easily and automatically clamp and tighten onto the respective nut or bolt head in response to the operator&#39;s turn, when the operator is sometimes several feet away from the respective nut or bolt. The instant invention not only achieves these objectives but is particularly well suited for those nuts, bolts and fittings of a hex or square variety. 
     A further problem relates to the need for the adjustable crowfoot to be removably attachable, yet sufficiently secured so as to essentially eliminate the risk of disengagement during use on heavy machinery. This is significant because the invention is particularly suited for the high level craft work on such things as engines, hydraulics, and other sophisticated machinery where it is not only important but in some cases governmentally required that the only tools that can be used are the disengagable type. Tools dropped in such sophisticated equipment cannot often be recovered without fully disassembling the equipment, an option that is not commonly or practically available on such equipment. Thus, is often the requirement for both practical and legal reasons, that all tools be pre-approved as the non-disengageable type. 
     Consequently, it is an object of the present invention not only to provide an adjustable crowfoot to substantially reduce the number of tools needed, but to provide such a crowfoot that is compact, maneuverable, easy and effective to use, relatively inexpensive to make, and is also reliable and utilizes the ability to lock and release on the respective fitting in direct response to the user, and further is non-disengagable. It is a further object that it be capable of accessing tight and hard to reach places, at a long distance utilizing an elongated rigid handle (extension) and that the crowfoot be adjustable from a distance. 
     The closest known device is disclosed in Schultz, U.S. Pat. No. 4,802,389. Schultz discloses and adjustable wrench that can be utilized with an extension as an adjustable crowfoot, however, Schultz&#39;s device would not work to meet the objectives of the present invention inasmuch as the adjustable jaw member in Schultz is situated so as to prevent or hinder the tool&#39;s accessing of the respective bolt, nut or fitting. To utilize the device in Schultz, one must approach the subject nut or bolt from the side. The present invention not only allows for a direct, hands-on approach to the bolt by the claws, but is far more precise; moreover, because the teeth of the rack in the instant invention are disposed away from the gripping area (just opposite to that shown in Schultz), the instant device allows for a precise, hex-shaped gripping area, the type of precision necessary to maximize the torque and gripping in extended and difficult to reach places. In short, the invention in Schultz would not work to achieve most of the objectives in the present invention. 
     Other objects and features of the invention and the manner in which the invention achieves its purpose will be appreciated from the foregoing and the following description and the accompanying drawings which exemplify the invention, it being understood that changes may be made in the specific method and apparatus disclosed herein without departing from the essentials of the invention set forth in the appended claims. 
    
    
     DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is an exploded view of the preferred mode of the invention. 
     FIG. 2 is a front view of the invention. 
     FIG. 3 is a side view of the invention looking into the direction A/A′ of FIG.  2 . 
     FIG. 4 is a perspective view of the invention in its completed form, and showing an extension. 
     FIG. 5 is a side view of the pinion gear. 
     FIG. 6 is a perspective view of the pinion gear. 
     FIG. 7 is a perspective view of the rack. 
     FIG. 8 is a bottom view of the rack in FIG.  7 . 
     FIG. 9 is an end view of the rack shown in FIG.  7 . 
     FIG. 10 is a side view of the rack. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The invention in the preferred mode is shown in FIG. 1 in an exploded view. The fixed claw,  1 , has planar face  19 , adjacent an angled surface  22 , which surface corresponds to the angles on a hex nut, bolt or fitting. Said angled surface  22  is immediately adjacent to flat planar surface  24 , which surface  24  is perpendicular to fixed claw face  19 . Open channel  26  receives the rack  13  and is further open to a larger track-receiving Channel  15 . Channels  15  and  26  extends through the fixed-claw member  1 . Adjustable claw member  23  has flat planar surface  21 , whose planar surface is parallel to that of surface  19  when the rack  13  to which the adjustable claw  23  is attached is inserted into the channels  15  and  26 . 
     Channel  15  is further open to the interior of the gear-receiving hole,  16 , so that the teeth  11  of the gear  5  interengage with corresponding teeth  10  of rack  13 . The gear  5  described in more detail further herein, rests against inner surface  14  of the fix-claw member  1 . The surface  14  is made sufficiently large to retain the gear  5  and so as to allow access to the extension-receiving cavity  8  through larger hole  12 . The extension-receiving cavity  8  extends through the gear  5  so as to allow access to it from either side of the gear  5 . Gear  5  rotatably sits inside the gear-receiving hole  16  and is rotatably secured in said hole by wire retainer  9  which wire retainer is of sufficient size to fit snugly around the gear  5  as will be seen further in FIG. 5, yet extend into the recessed gap  17  in gear-receiving hole  16 . Gear  5  is shown having at least one missing tooth (and only one tooth in a preferred mode) to allow hole  6 , which corresponds to a slot or other indicia  4  on the outside face  2  of the gear, the purpose of which is to gain access to the extension cavity  8  when the slot or indicia is matched. Access is achieved utilizing a pin inserted through hole  28 , then through hole  6  when the gear is aligned, so as to release the locking pin on the extension which will more clearly be seen in FIG.  4 . 
     In FIG. 2, the locking pin indicator  29  which corresponds to the locking pin indicator  4  in FIG. 1, is shown in a position with the fixed and adjustable jaw substantially open. In the preferred mode, when this indicator is rotated to position  32 , the jaws will be essentially closed and it is in this position that the holes  6  and  15  (in FIG. 1) align so as to allow access to the extension cavity  8 . Moreover, when the indicator,  29 , is approximately in the position shown as  34  in FIG. 2, the jaws  23  and  25  essentially open in their maximum position. 
     Also shown in FIG. 2 is the hex-surface  36  which is part of the adjustable claw  23  and is at an angle with relation to the adjustable claw gripping face  21  so as to correspond with the hex face  42  which together provide the approximate angles for receiving and gripping typical hex-head arrangements. Thus it can be seen that the teeth of the rack are disposed away from the gripping area, the gripping area extends opposite the teeth of the rack and, further, extends away from the extension cavity  38 . The continuous, preferably non-circular curve  25  of the fixed-claw portion, narrows to the distal end  33  to allow for a compact device that is precise, able to reach under and into hard-to-access places, around obstacles and still obtain a precise fit around hex and square heads and fittings and further maintain maximum torque. 
     FIG. 3 is a side view of FIG.  2 . The end  31  of the channels ( 15  and  26  in FIG. 1) is seen in the exterior of the fixed-claw portion. 
     FIG. 4 discloses and extension  51  having near its end  59  a spring-loaded pin  57  such that when pressed inwardly, the pin  57  allows the end  59  to be inserted into the extension cavity  61 . This pin, when extended, corresponds to the hole  6  in FIG. 1 ( 91  in FIG.  6 ). As discussed previously, and as shown in FIG. 4, with the indicator  63  aligned with the hole  65  an external pin inserted through the hole  65  can reach to the pin  57  in order to depress the pin  57  in order to remove the extension  51 . It is not uncommon to use a number of lengths of extensions, end to end, such that the end of the previous extension can fit into the hole  55  utilizing pin-receiving hole  53  all in order to reach tight, far-off places in the subject equipment being serviced. The extensions can sometimes reach as far as three feet or more in length. 
     FIG. 5 shows a side view of the gear. It has a first outer circular surface  71  having a diameter that essentially matches the inner diameter of the gear-receiving opening  16  and has an adjacent smaller circular portion  73  with a smaller diameter which is then adjacent to the gear teeth portion  75 , having a diameter (from outside of gear teeth) essentially the same as  71 . The gap  74  is created to allow for receiving of the clip retaining means  9  in FIG.  1 . Adjacent to the gear teeth portion  75  is the second and outer surface of the gear member comprising a cylindrical hub  77  having a bottom surface  78  parallel to  71 . This hub has a diameter in the preferred mode slightly larger than  73 , but less than the diameters of section  71  and  75 . The extension-receiving cavity is shown by channel defining lines  79  and  81  as extending through the gear member from surface  71  to hub surface  78 . Hole-indicating notches  83  and  85  are aligned vertically with the hole  87  to mark the location of said extension pin receiving hole  87 . 
     FIG. 6 shows a reverse perspective view of the gear showing the hub side up as well as the interior of the extension pin receiving hole  91 . It should be noted that the extension pin receiving hole  91  is also well-suited to fit and accept not only an extension having a pin retainer as described previously, but also a spring-loaded ball retainer. However, a spring-loaded ball retainer is not usually used in hard to reach places inasmuch as it is not sufficiently secure to assure the crowfoot does not disengage. 
     The adjustable claw is shown in more detail in FIGS. 7,  8 ,  9 , and  10  where it can be seen that the specific curve  95  as described allow for relatively easy access in limited areas, and further allows for easy turning of the device. 
     In use, as it has been described, one simply inserts the extension having spring-loaded pin retaining means into the extension-receiving cavity of the device so as to engage the pin-receiving hole in the gear member, thus locking the extension in place. If additional extensions are needed to reach further into the equipment, one can simply add extensions end to end. The crowfoot is brought forward to approach the subject nut, bolt or fitting deep within the equipment, so as to rest the adjustable claw face against the subject bolt, then as the device is turned to tighten it will be seen that the turning of the extension by the user causes an immediate turn of the body of the tool (the fixed claw toward the adjustable claw) and continued movement causes natural tightening of the two claws onto the bolt as further turning causes the bolt to turn in the desired direction. To unscrew the bolt (reversed) one simply removes the crowfoot and reconnects it from the other side. 
     Thus it can be seen is what has been invented is a precise and effective tool designed for and capable of accessing distant and difficult to reach places in sophisticated machinery while maintaining not only the precision during adjustability, but maintaining efficient and maximum transfer of the torque applied to the extension. Moreover this has been done with a device that is relatively compact, inexpensive to make, universal, and reliable in use. 
     While there have been shown and described particular embodiments of the invention, it will be obvious to those skilled in the art that changes and modifications may be made without departing from the invention or its equivalent, and, therefore, it is intended by the appended claims to cover all such changes and modifications as fall within the true spirit and scope of the invention.