WO1994019063A1

WO1994019063A1 - Mast climber - a device for ascending a profiled mast

Info

Publication number: WO1994019063A1
Application number: PCT/SE1994/000137
Authority: WO
Inventors: Christer Rhodin
Original assignee: Swedish Beacon Ab
Priority date: 1993-02-18
Filing date: 1994-02-18
Publication date: 1994-09-01
Also published as: SE508221C2; AU6159394A; SE9300544D0; SE9300544L

Abstract

The present invention is a device for ascending masts that are designed with a longitudinal groove (mast track). The invention comprises two foot plates (shoes) with specially designed toe mounts and one or two hand grips, all of which are entered and slides in the mast track and by means of which a person climbs up the mast, not unlike the ascending of telegraph pole by means of pole shoes. Sliding and locking of the toe mounts and the hand grips are controlled by the friction between the mast and fittings attached to the mounts. The function of the hand grips is primarily as a fix point for the cord to the safety harness of the climber.

Description

MAST CLIMBER - a device for ascending a profiled mast

BACKGROUND OF THE INVENTION

In order to perform work on the rig of a sailboat, beyond reach from deck, a boatswain often must ascend the mast , to the top or partly. Conventionally this is achieved by hoisting the person to perform the work in a boatswain's chair fastened to a halyard. This procedure requires an assisting person with considerable strength. Another possibility is to employ a mast equipped with permanent steps, a design which implies aerodynamical, aesthetical and prac¬ tical inconveniences.

PURPOSE OF THE INVENTION

The present invention is intended to facilitate for the person, who wants to ascend such a mast that is designed with a longitudinal groove or mast track, to do so in an easy way and in most cases without requirements for an assist¬ ing person or even a functioning halyard.

The use of the invention is primarily anticipated for cruising where the boat¬ swain under various conditions may be forced to ascend the mast.

DESCRIPTION OF THE INVENTION

The invention, here with the denomination "mast climber", is a device by means of which a person ascends such masts that are profiled with at least one longitudinal groove integrated with the mast or attached to the outside of the same. In reference to the rig of sailboats this groove is commonly denomi¬ nated mast track. The device consists of two foot parts, Fig. 1-2, which for safety reasons are hooked together by a cord of the length of a step with a snap-hook. Also for safety reasons it comprises one (or possibly two) hand¬ grip^), Fig. 3, which (one) is attached to the safety harness (in a conventional way) of the ascending person.

The foot parts, cf. Fig. 1. (viewed from behind) and Fig. 2. (side view), con¬ sists of a foot plate 4 with a clamp 5, or a similar contraption, to fasten the foot, and a toe mount 6 with a flexible connection to a glide 7. These glides are to be entered into the mast track where they, when released from load, are allowed to slide under control of the feet of the climbing person. When subject to load from the weight of the climber, the toe mounts are locked to the mast by the friction from the fitting 8. The toe mounts are symmetric with respect to a point between the feet, i.e. there is a right/left as well as an up/down symmetry and they are designed in such a way that the feet may pass each other like when climbing on a ladder, even though the glides of the toe mounts 7 never pass each other in the mast track. These toe mounts may in reality be designed in a number of ways, Fig. 1-2. exhibits a tubular design. Also a de¬ sign based on sheet metal has been tried but the former proved advantageous mainly due to lower weight and more appealing shape.

The glide 7 with its flexible connection to the toe mount 6 is carefully shaped so as to avoid damage to the mast track and to distribute the load evenly along its length. In the normal situation, the glide is prevented from sliding down freely by the weight of the foot parts. However, the foot parts are hooked to¬ gether by cord of a step's length in order to prevent the lower foot part from sliding down beyond reach when the load is released, and if the foot at the same time comes lose from the clamp 5. Optionally the toe mounts of the foot parts may be equipped with a spring giving the devise an initial load and fric¬ tion to the mast. Se further the description of the hand grip below.

The hand grip, Fig. 3, of which one or two might be employed, consists of a handle 9, a glide 10 and a friction fitting 1 1 , very similar to the ones for the toe mounts 7 and 8. The handle is flexibly connected to the glide by the mount 15. Unlike the foot parts, the hand grip must be designed such that it doesn't slide down the mast without the active operation of the climber. This is achieved by some kind of known spring contraption 12 and a separate locking arrangement 13 that may be activated for special needs. The main function of the hand grip is as a safety measure to prevent the climber from falling down. It also has loop fitting 14 for the connection the safety harness of the climber. Another function of the hand grip is to facilitate for the climber to keep his body tight to the mast while working freely on the rig in connection to the mast. Other supplementary but worthwhile functions may be as a temporary fix point for a spare halyard along the mast, a spare stay (for which there may be another loop fitting in the upper part of the handle), a lifting device, etc.

Claims

PATENT CLAIMS

1. Device denominated "mast climber" by means of which a person ascends such masts that are equipped with a longitudinal groove or mast track charac¬ terized by two foot plates with toe mounts (6) which are fastened to each foot and entered into the groove integrated in or attached to the mast, and which when loaded is prevented from sliding by the friction between the mast and the toe mount fitting (8), and with such a design of the toe mounts that the feet may pass each other when climbing even though the attach points to the mast doesn't.

2. Mast climber according to Claim 1 , characterized by glides (7 and 10 respectively) that are flexibly connected to the toe mounts (6), and in relevant cases to the mount of the handle (15), and which are entered into and sliding in the mast track, and which by its extension along the mast trac^ and its sur¬ face structure ascertains that the mast track isn't damage ^{Λ ~} deformed.

3. Mast climber according to any of Claim 1 or Claim 2, characterized by the toe mounts (6), and in relevant cases the hand grips (15), are equipped with spring loads (12) to increase the initial load on the friction fittings (8 and 1 1 respectively) so as to prevent the particular element from sliding in an un¬ intentional way.