Information
-
Patent Grant
-
6286625
-
Patent Number
6,286,625
-
Date Filed
Monday, March 27, 200024 years ago
-
Date Issued
Tuesday, September 11, 200123 years ago
-
Inventors
-
-
Examiners
Agents
-
CPC
-
US Classifications
Field of Search
US
- 182 133
- 182 134
- 182 192
- 182 5
- 182 221
-
International Classifications
-
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)
Foreign Referenced Citations (1)
Number |
Date |
Country |
174970 |
Sep 1906 |
DE |