EP0106645A1

EP0106645A1 - Climbing chocks

Info

Publication number: EP0106645A1
Application number: EP83306105A
Authority: EP
Inventors: Stephen Paul Bean; Mark Vallance
Original assignee: CAMTEC Ltd
Current assignee: CAMTEC Ltd
Priority date: 1982-10-08
Filing date: 1983-10-07
Publication date: 1984-04-25

Abstract

The invention relates to climbing chocks and has for its objective to improve on the traditional wedge-shape chock to render it more effective in an irregular generally tapered crack whilst maintaining a high degree of effectiveness in a smoth sided crack. This objective Is met by a construction comprising a generally wedge shaped body (1), a longitudinal side face (2) on the body, edge walls (3) on the body extending from each side of the side face and merging at a distance from the side face, said side face and said point where said edge walls merge being respectively convexly and concavely or respectively concavely and convexly curved in the longitudinal direction.

Description

This invention relates to climbing chocks. Of the many forms of climbing chocks used by mountain climbers and the like, a simple wedge shape has long been regarded as particularly effective. Hedge shaped chocks are provided in a variety of sizes but the tapered angle tends to be constant to fit the taper of a crack in a rock structure, that experience teaches is likely to be encountered. In any situation where the taper of a crack is substantially the same as the taper of the wedge, the chock is ideal in providing the greatest holding feature but this does not always occur. Normally, a particular size of chock can be fitted into an appropriate crack, but there is point contact beween the chock and the crack because of the almost inevitable irregularities that would be present. This does not detract seriously from the effectiveness of the wedge shape which still cooperates with the general taper of the crack, usually to provide a number of points of contact.
The object of the present invention is to improve the traditional wedge shaped chock to render it more effective in an irregular generally tapered crack whilst maintaining a high degree of effectiveness in a smooth sided crack.
According to the present invention, a climbing chock comprises a generally wedge shaped body, a longitudinal side face on the body, edge walls on the body extending from each side of the side face and merging at a distance from the side face, said side face and said point where said edge walls merge being respectively convexly and concavely or respectively concavely and convexly curved in the longitudinal direction.
The merging of the edge walls at a distance from the side wall can take one of several forms. Thus, in the lateral plane, the edge walls may be arcuate and meet at an "apex" at a distance from the side face. Each transversely arcuate edge wall may be struck from a different centre when the transverse cross-sectional shape of the chock becomes generally triangular, or both transversely arcuate edge walls may be struck from the same centre to produce a cross-sectional shape that is generally that of a segment of a circle and when the apex is to be regarded as the point on the periphery of the chock furthest from the side face. In this form it is the side face and the apex that are either oppositely convex or concave or oppositely concave and convex in the longitudinal direction with respect to the side face.
Equally the merging of the edge walls can be into an opposite longitudinal side face, to produce a chock that is, in the transverse plane, generally rectangular, and when it is the side face and the opposite side face that are either oppositely convex and concave or concave and convex in the longitudinal direction.
In any of its forms, the chock may have a side face that is flat in the lateral direction but which may itself be laterally concavely curved over all of or part of its width. In addition, the edge walls, whether arcuate or straight in the lateral plane, may be convexly curved in the longitudinal direction.
According to a further feature of the invention, a climbing chock comprises a generally wedge-shape body and an attachment for a climbing rope, said attachment being secured to the body and extending from the narrower end of the body in line with the longitudinal axis of the body, said body having a side face generally parallel to the major lateral axis of the body and edge faces extending from the side face said edge faces merging into an opposite side face, said side face and opposite side face being respectively concavely and convexly curved or convexly and concavely curved and meeting at a point at the narrower end of the body, and said edge faces each being convexly curved in the longituinal direction and meeting at the same point at the narrower end of the body, and there being a flat end face at the broader end of the body. The flat end face may lie at substantially 90° to the side face but it is highly desirable to have that end face angled at approximately 15° to the horizontal downwardly towards the side face when convex or opposite side face when convex as the case may be. By having the flat end face angled downwards towards the longitudinally convexly side face or opposite side face of the chock, there is a considerably reduced tendancy for any jamming of the chock in a crack as would prevent its reasonable ready removal from that crack when required.
Here again, the said side face in addition to being either convexly or concavely curved in the direction of the longitudinal axis may additionally be concavely curved in the direction of the major lateral axis of the body or, particularly when that side is convexly curved, may be provided with-a centrally located generally concave depression.
The said edge faces may be continuously convexly curved longitudinally from the thicker end of the body to their meeting point at the thinner end of the body. It may however be preferable for the convex curve of each edge face to merge into a concave curve towards the thinner end of the body to produce a distinct tail at the thinner end of the body. With climbing chocks in accordance with this feature, there is virtually guaranteed the provision of a minimum of four-points of contact between the chock and the walls of a crack whether that be two-points of contact to each side of the body or three-points of contact to one side and one-point of contact at the other. This being so an exceedingly safe wedging action can be virtually guaranteed between the chock and the crack and yet at the same time the shape is conducive to the chock being removed from the crack when required.
Several embodiments of the invention will now be described with reference to the accompanying drawings, in which :

Figure 1 is a perspective view of a first embodiment of the invention;
Figure 2 is a section on the line II-II of Figure 1;
Figure 3 is a perspective view of a second embodiment of the invention;
Figure 4 is a section on the line IV-IV of Figure 3;
Figures 5 to 11 are representative of the particular transverse cross-sectional shapes available for the embodiments of the invention illustrated in Figures 1 and 3;
Figure 12 is a perspective view of a third embodiment of chock according to the invention;
Figure 13 is a perspective view of a fourth embodiment of chock according to the invention; and
Figure 14 is a perspective view of a fifth embodiment of chock according to the invention.

In Figure. 1 a climbing chock is formed by a generally wedge shaped body 1 having a longitudinal side face 2 and edge walls 3 extending from each side of the side face. In this embodiment the edge walls are arcuate and meet at an apex 4 at a distance from the side face. The side face 2 is, in the longitudinal direction, of convex shape, and the longitudinal line of the apex 4 is oppositely of concave shape as can be seen more particularly in Figure 2. In the construction shown in Figures 3 and 4, the body 1 of the chock again has a side face 2 and edge walls 3 of arcuate form meeting at an apex 4. In this embodiment as is shown more particularly by Figure 4, the side face 2 is, in the longitudinal direction of concave form and the apex where the arcuate edge walls merge oppositely of convex form.
With the embodiments of Figures 1 and 3, the edge walls 3 of arcuate form can have the arcs struck from different centres. This has the effect of producing a chock which in the transverse plane is generally triangular, as is indicated in the forms of construction indicated by Figures 5 to 8. However as is indicated in Figures 9 to 11 it is equally possible for the arcuate edge walls to be struck from the same centre and when they merge at an apex which is to be taken as the point on the curve furthest from the side wall 2.
As is illustracted in Figures 1 and 3, the side wall 2 whilst,being either convex or concave in the longitudinal direction may be straight in the transverse plane. However it is equally possible for the side wall 2 itself to be of concave form in the lateral plane either over the whole of its width and height or over a part thereof. It is equally so that the side wall 2 can be provided with a transversly flat-bottomed recess extending over part of or all of its height. Again across Figures 5 to 11 there is illustrated by way of example a number of possible configurations.
In the further form of construction illustrated in Figure 12, the climbing chock again has a body 1 with a side wall 2 and edge walls 3. In this embodiment the edge walls 3 are generally parallel in the transverse plane adjacent the side wall 2 and merge in an opposite side face 5 at a distance from the side wall 2. In this embodiment the edge walls 3 are of convex form in the longitudinal direction such that in conjunction with the longitudinally concave side face 2 and longitudinally convex opposite side face 5 the side faces and the edge faces meet at a point 6 at the lower end of the-body. At the upper end of the body a flat end face 7 is provided that is angled at approximately 15⁰ to the horizontal downwardly towards the convexly formed opposite side face 5.
Generally similar considerations apply to Figure 13 where again the body 1 of the chock has a side face 2 and edge walls 3 that merge into an opposite side face 5. In this form of construction the side face 2 is longitudinally convex and the opposite side face 5 longitudinally concave and which, in conjunction with edge walls that are again longitudinally convex the walls meet at a point 6 at the lower end of the body. In Figure 13 the flat end face 7 is inclined downwardly at 15° to the horizontal towards the longitudinally convex side face 2.
Figure 12 indicates that the side face 2 can additionally be of concave form in the lateral plane whereas Figure 13 indicates that the side face 2 may be provided with a concave recess over part of its width and length.
Figure 14 shows a form of construction following the principle of Figure 12 but utilising arcuate side walls as is shown in the embodiments of Figures 1 to 11.
Figures 12 to 14 additionally show the connection of an attachment for a climbing rope. Thus, a wire loop 8 is provided, the free ends of which are secured in holes 9 extending through the body of a chock in line with the longitudinal axis of the body, with the arms of the loop extending out of the body from its narrower end.
With all forms of construction a considerably safer chock is provided in comparison with those simple wedge shapes known hitherto. Even where the construction uses a laterally flat side face 2 there is guaranteed a greater number of points of contact between the chock and the smoothest of tapered cracks in, e.g., a rock face, and with those forms of construction employing a laterally concave side face 2 or a side face 2 embodying a recess there is virtually guaranteed an absolute minimum of four points of contact.

Claims

1. A climbing chock comprising a generally wedge shaped body,a longitudinal side face on the body, edge walls on the body extending from each side of the side face and merging at a distance from the side face, said side face and said point where said edge walls merge being respectively convexly and concavely or respectively concavely and convexly curved in the longitudinal direction.

2. A climbing chock as in Claim 1, wherein the edge walls are convexly arcuate and meet at an apex at a distance from the side face.

3. A climbing chock as in Claim 2, wherein the edge walls are struck from different centres and when the transverse cross-sectional shape of the chock is generally triangular.

4. A climbing chock as in Claim 2, wherein the edge walls are struck from the same centre to produce a cross-sectional shape that is generally that of a segment of a circle.

5. A climbing chock as in Claim 1, wherein the edge walls are generally parallel adjacent the side face, and merge into an opposite longitudinal side face to produce a chock that is, in the transverse plane, generally rectangular, and when it is the side face and the opposite side face that are oppositely convex and concave or oppositely concave and convex in the longitudinal direction.

6. A climbing chock as in any of Claims 1 to 5, wherein the side face is flat in the lateral direction.

7. A climbing chock as in any of Claims 1 to 5, wherein the side face is laterally concavely curved over all or part of its width.

8. A climbing chock as in any of Claims 1 to 7, wherein the edge walls are convexly curved in the longitudinal direction.

9. A climbing chock comprising a generally wedge-shape body and an attachment for a climbing rope, said attachment being secured to the body and extending from the narrower end of the body in line with the longitudinal axis of the body, said body having a side face generally parallel to the major lateral axis of the body and edge faces extending from the side face said edge faces merging into an opposite side face, said side face and opposite side face being respectively concavely and convexly curved or convexly and concavely curved and meeting at a point at the narrower end of the body, and said edge faces each being convexly curved in the longitudinal direction and meeting at the same point at the narrower end of the body, and there being a flat end face at the broader end of the body.

10. A climbing chock as in Claim 9, wherein the flat end face is angled at approximately 15° to the horizontal downardly towards the convex side wall or opposite side wall.

11. A climbing chock as in any of Claims 1 to 10, wherein the edge faces are continuously convexly curved longitudinally to a meeting point at the thinner end of the body.

12. A climbing chock as in any of Claims 1 to 10, wherein the edge walls are convexly curved longitudinally from the thicker end of the body and merge into a concave curve towards the thinner end of the body to produce a tail at the thinner end of the body.