GB2057545A

GB2057545A - Portable steps

Info

Publication number: GB2057545A
Application number: GB7931069A
Authority: GB
Original assignee: CHINN N J L
Current assignee: CHINN N J L
Priority date: 1979-09-07
Filing date: 1979-09-07
Publication date: 1981-04-01
Also published as: GB2057545B

Abstract

A portable step ladder mounted on wheels or casters (17) includes a movable brake or anchorage (23) to hold it static on the floor and operated by lever (22), and a movable guard (25) also operated by lever (22) to block access to the step at the bottom end, unless the brake is engaged. When the brake is engaged the wheels are lifted clear of the ground. <IMAGE>

Description

SPECIFICATION Portable steps This invention relates to portable steps or stairs, as used for example in libraries or other stores having elevated shelves or racks. The invention may however be applied to portable sets of steps of any character or purpose.

The invention is particularly applicable to a portable set of steps including rollers, wheels or casters at the lower end, to facilitate movement.

Unless the upper end is very securely attached there is a risk that the whole set may move or even collapse and it is an object of the invention to provide means for improving the safety of anyone using the steps.

Broadly stated, the invention consists in a portable set of steps, including rollers, wheels or casters at the lower end, a controllable brake or anchorage to hold the lower end stationary, and a guard or warning device to prevent or discourage access to the stairs unless the anchorage is in its operative position.

According to a preferred feature of the invention the guard is mechanically linked to the brake or anchorage, and conveniently the guard comprises a movable bar or gate positioned to restrict access to the steps. The brake or anchorage may take various forms but in a particular preferred arrangement it is designed to engage the ground and simultaneously lift the rollers, wheels or casters clear of the ground.

In any case, the equipment preferably includes a manual operating member connected both to the brake or anchorage and to the guard or warning device to render them operative or inoperative as the case may be.

The invention may be performed in various ways and one specific embodiment will now be described by way of example, with reference to the accompanying drawings, in which: Figure 1 is a side elevation of the lower end of a portable set of steps according to the invention, Figure 2 is a partial rear view of the lower end of the steps, and Figure 3 is a partial front view of the steps.

In this example the invention is applied to a portable set of steps of the type as used for example in large libraries. The staggered treads 10 of the steps are located at either side in a framework consisting of two inclined parallel bars or tubes 11, 12, to which are attached side rails 1 3 connected by struts 14. Each pair of side bars 11, 12 are interconnected at their lower ends by a horizontal rail 1 6 into which is fitted a selfsteering caster 1 7. The upper end of the set of steps is not illustrated but may include hooks or friction pads or buffers of any conventional type.

In accordance with the invention the equipment is provided with an anchorage intended to restrict or prevent movement of the lower end on the ground, and also means to restrict access to the steps when the anchorage is inoperative.

The anchorage comprises a pair of short levers 1 8 positioned one at each end of a transverse pivoted shaft 1 9. Each of these levers 1 8 has a friction pad or foot 20 at its lower end, and at one end the shaft 1 9 is attached to an elongated operating lever 21 with a hand grip 22 at its upper end, by which the shaft and hence the two friction pads can be moved between their lower operative positions as illustrated in full lines in Figure 1 to an inoperative raised position as indicated at 23. It will be noted that when the friction pads are in their engaged lower positions the steerable casters 1 7 are lifted just clear of the ground. Thus in this position the lower end of the steps is effectively anchored or braked.

In addition the equipment includes an arrestor bar or gate to restrict access to the steps unless the anchorages are engaged. A horizontal transverse arrestor bar 25 is connected to a pair of swinging arms 26, one at each side, each arm being pivotally mounted on a pin 27 fixed to the respective side frame. A peg or stud 28 is fixed to each of these arms at its mid-point and is arranged to co-operate with a small bracket 29 carried by the operating lever 21. Thus it will be seen, by reference to Figure 1, that when the operating lever 22 is moved in a clockwise direction so as to swing the anchorage pads 20 into an inoperative position, the lever engages the peg 28 on the adjacent arm 26 and so swings the arrestor bar 25 up into the position indicated at 30 in Figure 1. The peg 28 is here fully engaged in the bracket 29 and further movement of both parts is limited.In this position the arrestor bar prevents access to the lower end of the steps. By swinging the lever 21 in the opposite direction the bracket 29 draws the peg 28 and hence the arm 26 in the anti-clockwise direction so as to lower the arrestor bar down to the level of the treads and hence provide free access to the steps.

It will be appreciated that a number of variations and modifications are possible. For instance, instead of using anchorage pads which lift the whole set of steps slightly clear of the ground, friction brakes may be arranged to act on.

the caster wheels, or the wheels themselves may be raised slightly to bring a fixed part of the steps into contact with the ground. Similarly, the arrestor bar or gate may be replaced by other preventative or warning devices.

1. A portable set of steps including rollers, wheels or casters at the lower end, a controllable brake or anchorage to hold the lower end stationary, and a guard or warning device to prevent or discourage access to the stairs unless the brake or anchorage is in its operative position.

2. A portable set according to claim 1, in which the guard is mechanically linked to the brake or anchorage.

3. A portable set according to claim 1 or 2, in which the guard comprises a movable bar or gate positioned to restrict access to the steps.

4. A portable set according to claim 3, in which the anchorage is arranged to engage the ground and simuitaneously lift the rollers, wheels or

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Portable steps This invention relates to portable steps or stairs, as used for example in libraries or other stores having elevated shelves or racks. The invention may however be applied to portable sets of steps of any character or purpose. The invention is particularly applicable to a portable set of steps including rollers, wheels or casters at the lower end, to facilitate movement. Unless the upper end is very securely attached there is a risk that the whole set may move or even collapse and it is an object of the invention to provide means for improving the safety of anyone using the steps. Broadly stated, the invention consists in a portable set of steps, including rollers, wheels or casters at the lower end, a controllable brake or anchorage to hold the lower end stationary, and a guard or warning device to prevent or discourage access to the stairs unless the anchorage is in its operative position. According to a preferred feature of the invention the guard is mechanically linked to the brake or anchorage, and conveniently the guard comprises a movable bar or gate positioned to restrict access to the steps. The brake or anchorage may take various forms but in a particular preferred arrangement it is designed to engage the ground and simultaneously lift the rollers, wheels or casters clear of the ground. In any case, the equipment preferably includes a manual operating member connected both to the brake or anchorage and to the guard or warning device to render them operative or inoperative as the case may be. The invention may be performed in various ways and one specific embodiment will now be described by way of example, with reference to the accompanying drawings, in which: Figure 1 is a side elevation of the lower end of a portable set of steps according to the invention, Figure 2 is a partial rear view of the lower end of the steps, and Figure 3 is a partial front view of the steps. In this example the invention is applied to a portable set of steps of the type as used for example in large libraries. The staggered treads 10 of the steps are located at either side in a framework consisting of two inclined parallel bars or tubes 11, 12, to which are attached side rails 1 3 connected by struts 14. Each pair of side bars 11, 12 are interconnected at their lower ends by a horizontal rail 1 6 into which is fitted a selfsteering caster 1 7. The upper end of the set of steps is not illustrated but may include hooks or friction pads or buffers of any conventional type. In accordance with the invention the equipment is provided with an anchorage intended to restrict or prevent movement of the lower end on the ground, and also means to restrict access to the steps when the anchorage is inoperative. The anchorage comprises a pair of short levers 1 8 positioned one at each end of a transverse pivoted shaft 1 9. Each of these levers 1 8 has a friction pad or foot 20 at its lower end, and at one end the shaft 1 9 is attached to an elongated operating lever 21 with a hand grip 22 at its upper end, by which the shaft and hence the two friction pads can be moved between their lower operative positions as illustrated in full lines in Figure 1 to an inoperative raised position as indicated at 23. It will be noted that when the friction pads are in their engaged lower positions the steerable casters 1 7 are lifted just clear of the ground. Thus in this position the lower end of the steps is effectively anchored or braked. In addition the equipment includes an arrestor bar or gate to restrict access to the steps unless the anchorages are engaged. A horizontal transverse arrestor bar 25 is connected to a pair of swinging arms 26, one at each side, each arm being pivotally mounted on a pin 27 fixed to the respective side frame. A peg or stud 28 is fixed to each of these arms at its mid-point and is arranged to co-operate with a small bracket 29 carried by the operating lever 21. Thus it will be seen, by reference to Figure 1, that when the operating lever 22 is moved in a clockwise direction so as to swing the anchorage pads 20 into an inoperative position, the lever engages the peg 28 on the adjacent arm 26 and so swings the arrestor bar 25 up into the position indicated at 30 in Figure 1. The peg 28 is here fully engaged in the bracket 29 and further movement of both parts is limited.In this position the arrestor bar prevents access to the lower end of the steps. By swinging the lever 21 in the opposite direction the bracket 29 draws the peg 28 and hence the arm 26 in the anti-clockwise direction so as to lower the arrestor bar down to the level of the treads and hence provide free access to the steps. It will be appreciated that a number of variations and modifications are possible. For instance, instead of using anchorage pads which lift the whole set of steps slightly clear of the ground, friction brakes may be arranged to act on. the caster wheels, or the wheels themselves may be raised slightly to bring a fixed part of the steps into contact with the ground. Similarly, the arrestor bar or gate may be replaced by other preventative or warning devices. CLAIMS

4. A portable set according to claim 3, in which the anchorage is arranged to engage the ground and simuitaneously lift the rollers, wheels or casters clear of the ground.

5. A portable set of steps according to any of the preceding claims, including a manual operating member connected both to the brake or anchorage and to the guard or warning device to render them operative or inoperative as the case maybe.

6. A portable set of steps substantially as described with reference to the accompanying drawings.