Rope climbing device

Information

  • Patent Grant
  • 6286625
  • Patent Number
    6,286,625
  • Date Filed
    Monday, March 27, 2000
    24 years ago
  • Date Issued
    Tuesday, September 11, 2001
    22 years ago
Abstract
A rope climbing device that attaches to a person's feet for assisting with ascending or descending along a rope. The rope climbing device has a frame that is shaped into a housing on one side and a base member on the opposing side. At least partially enclosed in the housing is a slide member that slides along the frame. Hooks protruding from the slide member are inserted into or engage a rope placed in the housing between a pair of pivoting cams. The downward force on the base member resulting from the user's weight moves the slide member upward relative to the frame. Due to this action, an actuating mechanism attached to the slide member pivots the pair of cams inward to tightly grip the rope, allowing the person to move his or her other foot upward or downward along the rope. When the downward force from the person's weight is released from the base member, springs attached to the cams cause the cams to pivot outward to an open position so the person may disengage the hooks from the rope and move his or her foot upward or downward.
Description




BACKGROUND OF THE INVENTION




1. Field of the Invention




The field of the present invention relates generally to devices that are used for descending or ascending ropes, cables and the like. In particular, the present invention relates to rope climbing devices that are capable of supporting a person's weight and making it easier for a person to climb upwardly or downwardly along a rope used as a fire escape or to ascent or descent a structure, mine, cave and other places.




2. Background




Rope climbing is generally thought to be limited to the realm of mountain climbers, firefighters and others having particular skill and training for safely ascending and descending on a rope, cable or similar materials. As such, people who climb ropes under these circumstances typically have specialized equipment which they use. This equipment is generally very sophisticated and requires considerable training and experience to safely use for ascending or descending vertical distances of any significant length. However, the need for others to ascend or descend along a rope who do not have the specialized equipment used by professionals and experienced climbers or who are not trained or experienced in the use of such equipment does arise on a not infrequent basis.




The need for the inexperienced person to ascend or descend on a rope can arise under various conditions. For instance, ropes and the like can be used in various rescue situations to save a person from injury or even death. Examples of few such situations include the need to exit the higher floors of a burning building, to climb down from a structure upon which a person has become stuck or to climb up a rope to escape rising flood waters or other conditions. With the prevalence of high rise buildings for work and homes, the potential for needing to use a rope for fire escape, in particular, is a more common possibility for the average person. Typically, the average person does not have the equipment, skill or training to safely ascend or descend along a rope. As a result, unfortunately, when the need does arise, the person is generally left unable to utilize a rope to effectuate a quick and safe exit from a dangerous situation (i.e., fire).




Various devices have been developed for use to assist persons with the ascent or descent along a rope. For the most part, the prior art devices are complex in design and require considerable training and experience to safely utilize. In addition, these devices are generally heavy, bulky to carry or store and expensive to purchase for the off chance it will be needed. U.S. Pat. No. 3,717,219 to Hoffman describes a device that comprises various straps that must go around the body and a friction apparatus that the rope is wound around in a specific manner to slow descent. This patent also describes the use of a foot apparatus for ascent that requires coordinated movement of both feet in order to sufficiently clamp and un-clamp the rope. U.S. Pat. No. 1,505,360 to Lowery describes the use of a leg or stirrup mounted device for climbing a rope that utilizes a cam-type of apparatus having serrations on the cam surfaces for engaging and clamping the rope by shifting the weight of the person using the device. These and other rope gripping devices have not be universally accepted for use by unskilled persons desiring to quickly and safely exit a building or other location to escape danger, including fire. What is needed, is a device that is relatively simple to use for safely ascending or descending along a rope by persons who do not have skill or experience with such devices or rope climbing in general.




SUMMARY OF THE INVENTION




The rope climbing device of the present invention solves the problems identified above. That is to say, the present invention provides a rope climbing device that is relatively simple to use, inexpensive to manufacture and adaptable for ascending and descending a rope, wire cable and other such climbing materials. Specifically, the present invention discloses a device that attaches to a person's foot and connects to a rope for relatively simple ascent or descent along the rope without the need for any special skills, technique or physical condition.




In the primary embodiment of the present invention, the rope climbing device comprises a frame having a first side and an opposing second side. The frame is shaped and configured to have a base member, center portion and a housing. The housing is on the first side of the frame and the base member extends in a generally perpendicular direction from the second side of the frame such that the housing is on one side of the frame and the base member is on the opposite side. The base member must be suitable for placement of a person's foot or shoe thereon during ascent or descent along a rope. The housing encloses, at least partially, a slide member that is slidably attached to the frame in a direction that is generally parallel to the plane of the frame. Protruding from the slide member is one or more hooks or hook-like elements that are suitable for at least partial insertion or engagement with the rope. In the preferred embodiment, the housing also encloses a pair of opposing cams that are pivotally attached to the frame and/or housing. The cams pivot between an open position and a gripping position. A spring disposed around the pivot shaft and between the cam and the frame or housing operatively engages the spring to force it to remain in the open position or to move it from the gripping position to the open position. An actuating mechanism, such as an actuator spring, is attached to and moves with the slide member. The actuating mechanism is also attached to the cams, such that upward movement of the actuating mechanism results in the cams pivoting inward to the gripping position.




To use the device of the present invention, the person desiring to ascend or descend along a rope securely attaches a device to each foot or shoe with a securing mechanism, such as a strap or other mechanism, that is attached to the frame, housing and/or base member. Once the device is fastened to the foot or shoe, the rope is disposed in the device between the two cams such that the hooks are at least partially inserted in or engage the rope. When a downward force, such as all or part of the person's body weight, is applied to the base member while the hooks are inserted in or engaged with the rope, the slide member moves upward relative to the frame or center portion of the frame. This upward movement of the slide mechanism causes the actuating mechanism to move the cams from the open position to the gripping position to tightly grip the rope therebetween. Once the rope is tightly engaged between the cams, the person can place their weight thereon and move the other foot upward or downward, depending on whether ascent or descent is desired, to engage the device on the other foot or shoe. In this manner, the person using the present invention climbs up or down the rope as if they were climbing stairs or a ladder.




The device of the present invention does not require the use of the person's hands to operate the device. The hands are left free to grip the rope or use one hand to grip the rope and the other hand to hold on to an object or another person. The present invention can also be utilized to move along a rope that is other than vertically disposed. For instance, with very little practice, the device of the present invention can be utilized to move along a rope that is strung horizontally, such as a rope that traverses a natural chasm or a gap between two structures.




Accordingly, the primary objective of the present invention is to provide a rope climbing device that relatively simple to make and easy to use for ascending or descending along a rope.




It is also an important objective of the present invention to provide a rope climbing device that securely attaches to a person's foot or shoe and which does not require use of the hands to operate.




It is also an important objective of the present invention to provide a rope climbing device that has a pair of cams pivotally attached to a frame having a sliding member that moves in response to a downward force on the base member attached to the frame such that the cams pivot to tightly grip a rope.




It is also an important objective of the present invention to provide a rope climbing device that utilizes one or more hooks protruding from a sliding member slidably attached to a frame to engage a rope disposed between a pair of pivoting cams that tightly grip the rope in response to a downward force on a base member attached to the frame.




Yet another important objective of the present invention is to provide a rope climbing device that allows a person to ascend or descend along a rope using body motions that are similar to ascending or descending stairs and ladders.




The above and other objectives of the present invention will be explained in greater detail by reference to the attached figures and the description of the preferred embodiment which follows. As set forth herein, the present invention resides in the novel features of form, construction, mode of operation and combination of parts presently described and understood by the claims.











BRIEF DESCRIPTION OF THE DRAWINGS




In the drawings which illustrate the best modes presently contemplated for carrying out the present invention:





FIG. 1

is a top view of the preferred embodiment of the present invention;





FIG. 2

is a back view of the embodiment of the present invention shown in

FIG. 1

;





FIG. 3

is a side view of the present invention with a portion of the housing removed to better show the cam and actuator mechanism;





FIG. 4

is a cross-sectional view of the present invention taken through


4





4


on

FIG. 3

;





FIG. 5

is a side view of the present invention with a portion of the housing removed to better show the cam and actuator mechanism in the open position;





FIG. 6

is a side view of the present invention with a portion of the housing removed to better show the cam and actuator mechanism in the gripping position;





FIG. 7

is a side view of an alternative embodiment of the present invention utilizing only one cam;





FIG. 8

is a back side view of the cams and actuating mechanism of the present invention; and





FIG. 9

is a side view of a cam showing the connection of the actuating mechanism to the cam.











DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS




With reference to the figures where like elements have been given like numerical designations to facilitate the reader's understanding of the present invention, and with particular reference to the present invention illustrated in

FIGS. 1 through 6

, the preferred embodiment of the present invention is set forth below. The rope climbing device, designated generally as


10


, allows a person to climb along rope


12


, generally in a ascending or descending manner. Rope


12


can be of any type of rope commonly used for climbing, such as ropes made out of cotton, nylon, combinations of cotton, nylon and/or other materials. In addition, rope


12


can be made out of materials not commonly used for ropes, such as various metals and composite materials that are suitable for the present invention described below. One end of rope


12


will be attached to the structure, mine, cave or other object that the person desires to ascend or descend from. For instance, rope


12


can be utilized as a fire escape tool that attaches to a window sill or other part of a building or structure so that the person may descend to safety below.




As shown in

FIGS. 1 through 6

, the rope climbing device of the present invention generally comprises frame


14


having a first side


16


and second side


18


opposite first side


16


. Frame


14


should be made from a strong material that can be fixedly shaped as desired and yet maintain that shape under loads typically expected from persons who may use device


10


(i.e., up to 300 pounds or so), so that the climber may bear his or her entire weight on device


10


. Because device


10


is intended to be stored until it is needed, which may be for some time, the material chosen for frame


14


should be somewhat corrosion resistant. Preferably, the material chosen for frame


14


should be lightweight, making it easy to carry to where it may be needed.




In the preferred embodiment, frame


14


is shaped to form housing


20


, base member


22


and center portion


24


. In one embodiment, frame


14


starts off as a generally cross-shaped frame prior to forming housing


20


and base member


22


. Housing


20


can be formed by bending in the “arms” of the cross towards the first side


16


of center portion


24


. Base member


22


can be formed by bending the bottom of frame


14


upward towards the center portion


24


on second side


18


. Other configurations are also possible. In fact, frame


14


, housing


20


and base member


22


can comprise three separate pieces that are joined to form the device


10


of the present invention. In this configuration, housing


20


can be attached to the first side


16


of frame


14


and base member


22


can be attached to the second side


18


of frame


14


. The purpose of housing


20


is to provide some level of protection to the components that are housed in housing


20


and provide support for those components. For purposes of general use of the present invention, however, it is not necessary that housing


20


fully enclose or seal the components housed therein. In fact, as described below and best shown in

FIG. 1

, rope


12


must be able to easily enter housing


20


in order for device


10


to function as a rope climbing device. If deemed desirable, device


10


cannot use housing


20


and still function as set forth below. Base member


22


should extend outwardly in a generally perpendicular relationship from frame


12


or center portion


24


a sufficient distance that the person utilizing device


10


to climb a rope can place his or her foot or shoe (shown as


26


in

FIGS. 1 and 2

) on base member


22


for support and to make device


10


grip rope


12


during the climbing process. For comfort and safety, base member


22


should be sized and configured to extend outwardly far enough that the full width of the typical foot or shoe


26


can rest on base member


22


(i.e., a distance of three to four inches). If desired, a hinge (not shown) can be utilized to allow base member


22


to fold up when not in use and fold down when device


10


will be used for climbing. Naturally, any such hinge must be sufficiently strong to support the weight designed for device


10


as a whole.




Slidably attached to the first side


16


of frame


14


is slide member


28


. Slide member


28


should be able to freely slide in a direction generally parallel to frame


14


or center portion


24


. Slide member


28


is housed within frame


14


. Protruding from slide member


28


is hook


30


, which prevent slide member


28


from falling through frame


14


. Hook


30


should be sized and configured to be adaptable for at least partial insertion into rope


12


for use of device


10


to ascend or descend along rope


12


. Hooks


30


can be shaped as shown or can be more of a spike, nail or similar shape. Hooks


30


must be of sufficient strength to not break under the loads and forces typically expected during use of the present invention. Preferably, hooks


30


will protrude from slide member


28


in a generally perpendicular direction relative to frame


14


or center portion


24


. Other angles, such as a downward angle, for hooks


30


are possible. However, the generally perpendicular hook


30


direction is most suitable for both ascent and descent along rope


12


. As shown in the various figures, the preferred embodiment utilizes more than one hook


30


in device


10


. The use of multiple hooks


30


is desirable to ensure hook


30


engages rope


12


and, for safety purposes, as a back-up in case one hook


30


is damaged and cannot function as described in more detail below. Although only two such hooks


30


are shown, any number of hooks can be utilized with device


10


. The preferred embodiment, as shown, utilizes two hooks


30


to balance the need for safety and the functionality of device


10


. An excessive number of hooks


30


may make the function of device


10


more difficult and, therefore, less safe than the use of fewer hooks


30


. Hook


30


should be fixedly attached to slide member


28


such that when force is applied to base member


22


(i.e., when the weight of the person is place downward on base member


22


) while hook


30


is engaged in rope


12


, the slide member


28


will easily slide upward relative to frame


14


attached to or integral with base member


22


. The preferred embodiment also includes a slide housing


32


attached to frame


14


such that it encloses hooks


30


to protect hooks


30


from damage. Hooks


30


should protrude from a slot


34


in slide housing


32


a sufficient distance to be able to engage rope


12


so device


10


can function as set forth herein.




Also attached to first side


16


of frame


14


is at least one cam


36


. In the preferred embodiment, as shown in

FIGS. 1

,


3


,


5


and


6


, two cams


36


are used. Cams


36


are pivotally attached to frame


14


with use of pivot shaft


38


. Disposed around pivot shaft


38


and between cam


36


and first side


16


of frame


14


is a spring


40


that operatively engages each of cams


36


to hold cams in the open position


42


shown in FIG.


5


. Springs


40


should provide enough force on cams


36


that they are not easily moved to the gripping position


44


, shown in

FIG. 6

, which results from the downward force on base member


22


as describe below. When this downward force is removed, springs


40


should quickly move cams


36


from the gripping position


44


to the open position


42


. Cams


36


should be spaced apart a sufficient distance that rope


12


can be placed between cams


36


when in the open position


42


. When in the gripping position


44


, cams


36


must tightly grip rope


12


so as to prevent undesirable and potentially dangerous slippage of device


10


down rope


12


while climbing. Cams


36


should be shaped so as to be able to tighten on a range of ropes


12


having different diameters. The typical “cam” shape, as shown in

FIGS. 3

,


5


and


6


, should be sufficient for this purpose. The edge of the cams


36


that contact the rope


12


can be smooth, as shown, or it can be serrated to improve the gripping action of the cams


36


against rope


12


.




In an alternative embodiment of the present invention, shown in

FIG. 7

, one of the cams


36


can be replaced by a cam resistor


46


, which can be a piece of solid metal spaced apart from the single cam


36


such that as cam


36


moves from the open position


42


to the gripping position


44


, cam


36


compresses the rope


12


between cam


36


and cam resistor


46


. In this embodiment, the cam resistor


46


does not pivot and, as a result, does not require spring


40


to move it back in the open position


42


. While this embodiment can function as desired, it is not the preferred embodiment due to the ability of the dual cam


36


arrangement to more tightly grip rope


12


to prevent slippage.




Connecting cams


36


to slide member


28


is an actuating mechanism, such as actuator spring


48


shown in the accompanying figures, that moves cams


36


from the open position


42


to the gripping position


44


as slide member


28


moves upward relative to frame


14


as a result of a downward force on base member


22


. As shown in

FIGS. 3

,


5


and


6


, the actuating mechanism


48


can be a spring bar attached at or near its middle to slide member


28


at one of the hooks


30


and at or near its ends to cams


36


(when two cams are used). Actuating mechanism


48


helps prevent slide member


28


from falling through frame


14


. As shown in

FIGS. 8 and 9

, actuating mechanism


48


of the preferred embodiment is hooked into cams


36


by bending the end of actuating mechanism


48


at an angle of approximately


90


degrees and inserting the end into cam


36


. This prevents actuating mechanism


48


from disconnecting from cams


36


. As shown in

FIGS. 5 and 6

, when the cams


36


are in the open position


42


, the actuating mechanism


48


does not apply any force or supplies an insufficient force to overcome the effect of springs


40


that hold the cams


36


in the open position


42


. As the base member


22


is forced downward due to the weight of the person using device


10


, slide member moves upward relative to frame


14


. This action moves the center of actuating mechanism


48


upward and brings its ends inward, thereby pivoting cams


36


inward towards rope


12


to tightly grip rope


12


.




To secure the device to a persons foot or shoe


26


, device


10


should use a securing mechanism, such as the strap


50


shown in

FIGS. 1 and 2

. As shown, strap


50


can connect to base member


22


and the top of housing


20


. Alternatively, strap


50


can connect to frame


14


, circumvent the entire device or any of various other configurations in order to provide a mechanism for securely attaching device


10


to foot or shoe


26


. As is known, instead of a single strap, securing mechanism


50


can comprise a plurality of straps or various tying, buckling and other securing mechanisms, including combinations thereof. The configuration of base member


22


and strap


50


will generally resemble a stirrup-like device that is suitable for placement of the foot or shoe


26


therein and then securely fastening the device


10


to the foot or shoe


26


. Preferably, once strap


50


or other securing mechanism is securely fastened to the foot or shoe


26


, device


10


should move in unison with the foot or shoe


26


.




In use, the person who desires to utilize device


10


to ascend or descend a rope


12


will attach device


10


to his or her foot or shoe


26


by sufficiently opening strap


50


to allow the person to place his or her foot or shoe


26


on top of base member


22


or between base member


22


and strap


50


and then securely fastening strap


50


so as to secure device


10


to foot or shoe


26


. The person then securely places a device


10


on the other foot or shoe


26


. Once one end of the rope


12


is attached to a window sill, structure or other non-movable object, the person places the rope


12


in device


10


between cams


36


such that hooks


30


are at least partially inserted in or engaged by rope


12


. Downward force from the person's weight on base member


22


while hooks


30


are engaged will result in the upward movement of slide member


28


relative to frame


14


, causing the actuating mechanism


48


to pivot cams


36


from the open position


42


to the gripping position


44


so that device


10


tightly and securely grips rope


12


. The same process is repeated for the person's other foot.




To ascend or descend rope


12


, the person merely moves their feet as they would if they were ascending or descending stairs or the like. By taking the weight off of one foot, the downward force on base member


22


is released and springs


40


pivot cams


36


from the gripping position


44


to the open position


42


. This allows the person to disengage hooks


30


from rope


12


and move his or her foot


26


upward or downward (depending whether ascent or descent is desired) a comfortable distance where the device


10


re-engages rope


12


and the process is repeated. As can be determined from the description of the operation of device


10


, use of device


10


does not require the person to utilize their hands in conjunction with device


10


. This frees the person to utilize their hand or hands to hold onto rope


12


or other objects while ascending or descending along rope


12


.




While there is shown and described herein certain specific alternative forms of the invention, it will be readily apparent to those skilled in the art that the invention is not so limited, but is susceptible to various modifications and rearrangements in design and materials without departing from the spirit and scope of the invention. In particular, it should be noted that the present invention is subject to modification with regard to the dimensional relationships set forth herein and modifications in assembly, materials, size, shape, and use.



Claims
  • 1. A rope climbing device for climbing a rope, comprising:a frame having a first side and an opposing second side; a base member attached to said frame, said base member substantially perpendicular to said frame, said base member sized and configured for placement of a foot or shoe thereon; a slide member slidably connected to said frame; a hook protruding from said slide member; a cam pivotally attached to said frame; a second cam pivotally attached to said frame, said second cam sufficiently spaced apart from said cam for the rope to be engaged between said cam and said second cam; a spring operatively engaging said cam for holding said cam in an open position and for moving said cam from a gripping position to said open position; and actuating means operatively interconnecting said slide member and said cam for moving said cam from said open position to said gripping position, said actuating means also operatively interconnecting said slide member and said second cam for moving said second cam from said open position to said griping position.
  • 2. The rope climbing device according to claim 1 further comprising a housing on said first side of said frame, said cam and said second cam disposed in said housing.
  • 3. The rope climbing device according to claim 1 further comprising a second spring operatively engaging said second cam for holding said second cam in said open position and for moving said second cam from said gripping position to said open position.
  • 4. The rope climbing device according to claim 1, wherein said hook protrudes from said slide member in a direction generally perpendicular to said slide member.
  • 5. The rope climbing device according to claim 1, wherein said slide member slides substantially parallel to said frame.
  • 6. The rope climbing device according to claim 1, wherein said hook is sized and configured to be adaptable for at least partial insertion into the rope.
  • 7. The rope climbing device according to claim 1 further comprising securing means attached to said device for securing the foot or shoe to said base member.
  • 8. The rope climbing device according to claim 7, wherein said securing means comprises one or more strap members attached to said frame.
  • 9. The rope climbing device according to claim 1 further comprising a plate housing attached to said frame, said plate housing having a slot, said hook protruding past said plate housing through said slot.
  • 10. A rope climbing device for climbing a rope, comprising:a frame having a first side and an opposing second side; a base member extending from said second side of said frame, said base member substantially perpendicular to said frame, said base member sized and configured for placement of a foot or shoe thereon; a slide member slidably connected to said first side of said frame, said slide member movement being substantially parallel to said frame; a hook protruding from said slide member, said hook sized and configured to be adaptable for at least partial insertion into the rope; a pair of cams pivotally attached to said first side of said frame, said pair of cams sufficiently spaced apart for the rope to be engaged between said pair of cams; a spring operatively engaging said pair of cams for holding said pair of cams in an open position and for moving said pair of cams from a gripping position to said open position; and actuating means operatively interconnecting said slide member and said pair of cams for moving said pair of cams from said open position to said gripping position.
  • 11. The rope climbing device according to claim 10 further comprising a housing on said first side of said frame, said pair of cams disposed in said housing.
  • 12. The rope climbing device according to claim 11 further comprising securing means attached to said device for securing the foot or shoe to said base member.
  • 13. The rope climbing device according to claim 10 further comprising a plate housing attached to said frame, said plate housing having a slot, said hook protruding past said plate housing through said slot.
  • 14. The rope climbing device according to claim 10, wherein said hook protrudes from said slide member in a direction generally perpendicular to said slide member.
  • 15. A rope climbing device for climbing a rope, comprising:a frame having a first side and an opposing second side, said frame shaped and configured to form a housing on said first side of said frame, a base member on said second side of said frame and a center portion between said housing and said base member, said base member substantially perpendicular to said center portion of said frame, said base member sized and configured for placement of a foot or shoe thereon; a slide member slidably connected on said first side of said frame to said center portion of said frame, said slide member movement being substantially parallel to said center portion of said frame; a hook protruding from said slide member, said hook sized and configured to be adaptable for at least partial insertion into the rope; a pair of cams pivotally attached to said first side of said frame, said pair of cams sufficiently spaced apart for the rope to be engaged between said pair of cams; a spring operatively disposed between each of said cams for holding said cams in an open position and for moving said cams from a gripping position to said open position; and actuating means operatively interconnecting said slide member and each of said cams for moving said pair of cams from said open position to said gripping position.
  • 16. The rope climbing device according to claim 15, wherein said hook protrudes from said slide member in a direction generally perpendicular to said slide member.
  • 17. The rope climbing device according to claim 15 further comprising securing means attached to said device for securing the foot or shoe to said base member.
  • 18. The rope climbing device according to claim 15 further comprising a plate housing attached to said center portion of said frame, said plate housing has a slot, said hooks protruding past said plate housing through said slot.
  • 19. A rope climbing device for climbing a rope, comprising:a frame having a first side and an opposing second side; a base member attached to said frame, said base member substantially perpendicular to said frame, said base member sized and configured for placement of a foot or shoe thereon; a slide member slidably connected to said frame; a hook protruding from said slide member, said hook sized and configured to be adaptable for at least partial insertion into the rope; a cam pivotally attached to said frame; a cam resistor attached to said frame, said cam resistor sufficiently spaced apart from said cam for the rope to be engaged between said cam and said cam resistor; a spring operatively engaging said cam for holding said cam in an open position and for moving said cam from a gripping position to said open position; and actuating means operatively interconnecting said slide member and said cam for moving said cam from said open position to said gripping position.
  • 20. The rope climbing device according to claim 19, wherein said cam resistor is a second cam pivotally attached to said frame.
  • 21. The rope climbing device according to claim 20 further comprising a second spring operatively engaging said second cam for holding said second cam in said open position and for moving said second cam from said gripping position to said open position.
  • 22. The rope climbing device according to claim 20, wherein said actuating means operatively interconnects said slide member and said second cam for moving said second cam from said open position to said gripping position.
US Referenced Citations (8)
Number Name Date Kind
580794 Money Apr 1897
1505360 Lowery Aug 1924
1516564 Barthelemy Nov 1924
1895571 Hein Jan 1933
3717219 Hoffman Feb 1973
3724593 O'Keefe Apr 1973
3938620 Nothiger Feb 1976
4531610 Fertier Jul 1985
Foreign Referenced Citations (1)
Number Date Country
174970 Sep 1906 DE