GB2179902A

GB2179902A - Suspension mechanism for a movable board used as an audiovisual aid

Info

Publication number: GB2179902A
Application number: GB08522242A
Authority: GB
Inventors: Heikki Metsa-Ketela
Original assignee: WULFFE Oy AB
Current assignee: WULFFE Oy AB
Priority date: 1985-09-07
Filing date: 1985-09-07
Publication date: 1987-03-18
Also published as: GB8522242D0

Abstract

The board 4 is suspended by rollers 2 moveable along a rail 1. The rollers have a shank portion 6 which lie across the edge 3 of the rail so that when the board is freely hanging its weight is at least partially transmitted through the shanks to the edge to obviate board movement. The shanks are disengaged, to move the board along the rail, by lifting and/or pulling the board's lower edge. <IMAGE>

Description

SPECIFICATION Suspension mechanism for a movable board used as an audiovisual aid The present invention concerns a mechanism for the suspension of objects, such as audiovisual aids, so as to permit sideways movement, using at least one sliding means, such as a roller, moving in the groove of a suspension rail mounted with the groove upwards.

Such rails are used e.g. in classrooms for the suspension of various audiovisual aids, such as blackboards, screens etc. Using some kind of sliding means, these can be moved sideways as desired.

So far, the biggest problem has been how to achieve a suspension mechanism that allows the board to be freely moved in the sideways direction while still providing a secure hold to keep the board in the desired place. For example, a blackboard is difficult to write on unless it remains firmly in place.

Attempts have been made to solve this problem e.g. by making the sliding means of a material with a relatively high coefficient of friction. This naturally means that it is considerably more difficult to move the board.

The Swedish patent n:o 389012 employs a steel peg with a rounded head as the sliding mens. This, too, is a compromise between movability and stability, neither of which is adequate in this prior-art suspension mechanism.

To improve movability, rollers have been used as sliding means, but with no braking mechanism these have proved to be too unstable.

The object of the present invention is to achieve a suspension mechanism that primarily employs sliding means providing easy movement, while still ensuring stability when the object suspended is to be kept firmly in place, e.g. when a blackboard is being written on.

Thus the invention is characterized in that the shank of the sliding means lies across the edge of the slide rail in such manner that when the object suspended, e.g. a blackboard, is freely hanging on the rail, the force of its weight is at least partially transmitted through the shanks to the rail edge, and that the shanks are disengaged from contact with the rail edge when the board is lifted and/or pulled by its lower edge.

The principal advantage of the invention is that it permits easy movement of the object in a simple manner, while at the same time ensuring stability when at rest. To disengage the shank of the sliding means from the rail edge, the board needs only to be slightly tilted by lifting or pulling it by its lower edge. In this position the board can be easily moved sideways, being provided with sliding means such as rollers.

The invention is further characterized in that the slide rail is provided with a protruding edge on one side of the groove along the whole length of the rail, this protrusion serving to prevent the sliding means from slipping out of the groove when the board is moved.

An advantageous embodiment of the invention is characterized in that a fixed sleeve is palced on the shank of the sliding means so that it covers at least part of its length. This arrangement offers the advantage that the groove need not be very deep, which means e.g. that the roller can be more easily turned in the groove relative to the logitudinal axis of the rail.

An advantageous embodiment of the invention is characterized in that the sliding means consist of two rollers mounted on a frame supporting the board and attached on its backside. The rollers are best placed as far apart as possible, but still so as to remain out of sight behind the board. The supporting frame permits easy installation of the rollers.

A further advantageous embodiment of the invention is characterized in that the ends of the horizontal tube of the supporting frame are bent towards the suspension rail to permit the corner suspension pins placed at the ends of the tube to remain in the groove. The main advantage of this arrangement is that the board can be placed in the corner of a room if both walls are provided with rails. Since the ends of the tube extend further out than the rollers, the latter remain outside of the groove when the board is suspended in a corner.

In the following, the invention is described in detail, reference being made to the drawings attached, wherein: Figure 1 presents the suspension mechanism of the invention in top view.

Figure 2 presents a section along the line ll-ll through the mechanism in Fig. 1.

Figure 3 presents the same sectional view as Fig. 2, except that the board is now tilted so as to permit sideways movement.

Fig. 1 presents a top view of the suspension mechanism of the invention. On the upper side of the slide rail fixed on the wall there is a groove 1. in which the board 4 is suspended by means of two rollers 2. A horizontal tube 7 is attached on the backside of the board, and the shafts, shown by broken lines, of the rollers 2 are fixed on this tube.

The ends of the horizontal tube 7 are bent towards the groove 1 and provided with pins 8 for suspension in a corner, these pins moving in the groove along with the rollers 2. The shafts of the rollers 2 are provided with fixed sleeves 9 on them, so that when the board 4 hangs freely on the rail, the sleeves rest on the edge 3 of the slide rail groove 1 as shown in Fig. 2, the friction between these parts thus preventing movement of the rollers 2 and therefore also of the board 4.

In Fig. 2 the shank is of solid structure with a collar swell, whereas in the embodiment shown in Fig. 3 the shank consists of the roller shaft and a sleeve 9 around it.

As shown by Fig. 3, the sleeves can be disengaged from contact with the- edge of the groove 1 by tilting the board with a pull at its lower edge. The groove 1 is provided with a protruding edge 5 to prevent the rollers from slipping out of the groove when the board is tilted.

When the board 4 is in the tilted position, the sleeves 9 thus being disengaged from contact with the edge 3, the board can be moved sideways by means of the rollers 2.

When the board has been moved to the desired place, its lower edge is released and allowed to rest against the wall. This causes most of the weight of the board to be applied through the sleeve 9 to the edge 3, the friction between these parts thus locking the board in place.

When the board is to be suspended in a corner of a room, special advantage is derived from the ends of the horizontal tube 7 being bent towards the groove 1 and provided with corner suspension pins 8. Suspension in a corner position would be impossible if the board were to be supported by the rollers, because they do not fit into the groove 1 if they are turned diagonally relative to the groove. Therefore, the suspension pins 8 at the ends of the horizontal tube 7 are placed in the grooves 1 of the slide rails on the two walls. In this position the rollers 2 are not in the grooves but hand free outside them, being placed in line with the ends of the tube 7.

It is obvious to a person skilled in the art that the invention is not restricted to the embodiment described above as an example, but may instead be varied as specified in the fol

Claims

lowing claims. CLAIMS

1. A mechanism for the suspension of objects, such as audiovisual aids, so as to permit sideways movement, using at least one sliding means (2), such as a roller, moving in the groove (1) of a suspension rail mounted with the groove turned upwards, characterized in that the shank (6) of the sliding means (2) lies across the edge (3) of the suspension rail groove (1) in such manner that at least part of the weight of the object, e.g. a blackboard, when hanging free, is transmitted via the shanks (6) to the edge (3), and that the shanks can be disengaged from contact with the groove edge by lifting and/or pulling the board (4) by its lower edge.

2. A suspension mechanism according to claim 1, characterized in that the slide rail is provided with a protruding edge (5) on one side of the groove (1) along the whole length of the rail to prevent the sliding (2) means from slipping out of the groove when the board (4) is moved.

3. A suspension mechanism according to claim 1 or 2, characterized in that at least part of the shank of the sliding means (2) is surrounded by a fixed sleeve (9).

4. A suspension mechanism according to one of the claims 1-3, characterized in that the sliding means consist of two rollers (2) fixed on a supporting frame attached to the backside of the board (4).

5. A suspension mechanism according to claim 4, characterized in that the ends of the horizontal tube (7) of the supporting frame are bent towards the suspension rail to allow the corner suspension pins (8), fixed at the tube ends, to remain in the groove (1).

6. A mechanism for the suspension of objects, such as audiovisual aids, so as to permit sideways movement as claimed in Claim 1, substantially as herein described with reference to and as illustrated by the example shown in the accompanying drawings.