GB2150913A

GB2150913A - Self propelled carriage

Info

Publication number: GB2150913A
Application number: GB08321420A
Authority: GB
Inventors: Hugh Kane
Original assignee: Individual
Current assignee: Individual
Priority date: 1983-08-09
Filing date: 1983-08-09
Publication date: 1985-07-10
Also published as: GB8321420D0

Abstract

A self propelled carriage for remotely controlled movement along an elongate structure such as a column, an angled wire stay or a tube, and intended to carry e.g. inspection equipment, has a framework 10, 12 or 40 which extends transversely of the elongate structure. The framework may comprise a pair of parallel frames 10, 12 longitudinally spaced and interconnected by piston and cylinders 14, with a plurality of pressure pads 16 on each frame. Each set of pads is releasably engageable against the surface of the structure whereby alternate sets of pads can engage so that the respective frame 10 or 12 remains stationary to allow the piston and cylinders to move the other frame and, by stepwise movements propel the framework. Alternatively the framework comprises one frame 40 carrying a plurality of endless tracks 42 which form the propelling means and the pressure means. <IMAGE>

Description

SPECIFICATION Self propelled carriage This invention relates to a self propelled carriage for remotely controlled movement along an elongate structure. Such structures may comprise upright columns, pillars, poles and lighting standards, angled wire stays for example on suspension bridges, and horizontal tubes and pipes; also offshore structures. The carriage is intended to carry inspection equipment or work equipment such as paint spray guns and to be used mainly externally but it can also be used internally of hollow structures.

According to the present invention there is provided a self propelled carriage comprising a framework adapted to locate transversely of an elongate structure, means to propel the carriage along the length of the structure in each direction and means remote from the carriage to control said pressure and propelling means.

Preferably the framework comprises a pair of parallel frames longitudinally spaced and intercon nected by piston and cylinder means and pressure means comprising a plurality of pressure pads on each frame, each set of pads being releasably en gageable against the surface of the structure whereby alternate sets of pads can engage so that the respective frame remains stationary to allow the piston and cylinder means to move the other frame and, by stepwise movements propel the framework.

Alternatively the framework comprises one frame carrying a plurality of caterpillar type tracks which comprise the pressure means, said tracks being adapted to engage the surface of the structure and remain so engaged to support the car riage thereon or therein and said caterpillar type tracks being also the propelling means whereby continuous movement of the framework along the structure can be achieved.

Embodiments of the present invention will now be described, by way of example, with reference to the accompanying drawings, in which: Fig. 1 is an elevation of a self propelled carriage according to one embodiment of the invention showing the upper and lower parts of the carriage from different angles; Fig. 2 is a plan view of the carriage framework; Fig. 3 is a side view of the frame; Fig. 4 is a circuit diagram of the remote control; and Fig. 5 is a sectional side view illustrating a detail of the carriage according to a second embodiment.

Referring firstly to Figs. 1 to 4, a self propelled, remotely controlled carriage comprises a pair of parallel frames 10, 12 interconnected by three pistons and cylinders 14. In this embodiment each frame is triangular and carries three inwardly fac ing pressure pads 16 at the end of rams 18 dis posed at the three corners of the frame. Fins 20 extend outwardly from the triangular frames and carry the rams 18 as described more fully herein after.

In this embodiment also, the rams are controlled pneumatically; a pair of ring mains 22, 24 are provided for each frame being connected respectively to the outer and inner ends of the ram cylinders. A third ring main 26 at each frame connects to the respective ends of the three pistons and cylinders 14. The ring mains have leads to a control consul (not shown) remote from the carriage and from which the various sets of rams 18 and pistons and cylinders 14 are operated, as illustrated in the circuit diagram of Fig. 4.

The fins 20 have an elongate box section 25 and a vertical U-shaped projection 26 at their outer ends. On the upper frame, the projection extends downwards, on the lower frame they extend upwards. A bracket 28 is slidably mounted in the box section of each fin and at its inner end has a vertical projection 29. The holding ram is attached at its inner end between the limbs of the bracket projection 29 and at its outer end between the limbs of the fin projection 26. When the ram is extended or retracted, the bracket moves with it.

The carriage is for location around an elongate structure such as a lighting standard, not shown; for this reason, the triangular frames can be split bu unfastening two sets of bolts 30, locating the frames in position around the standard and rejoining the parts of the frames.

The carriage is moveable by a sequence of operations whereby one frame is clamped to the standard, the pistons and cylinders 14 are operated in one direction to move the other frame after which that other frame is clamped, the first frame is released and the piston and cylinders 14 operated in the reverse direction.

If the lower frame 12 is first clamped to the upright standard, the piston and cylinders 14 extend to raise the upper frame, after which the lower frame is drawn up by retraction of the pistons and cylinders 14. In this stepwise manner the carriage can be raised to the top of the standard. It can be lowered in a similar manner and where, for example, the carriage is filled with paint spray guns, these guns can be operated during the descent, to paint the standard.

The frames may be other than triangular and other than closed; for example a part-circular frame may be provided forming a major arc of the circle but with a gap sufficient, on retraction of two of the holding rams, to locate the standard therein, the holding rams being positioned as before in substantially triangular disposition.

In a second embodiment Fig. 5 the framework comprises a single frame 40 which for the purposes of description may be triangular with three holding rams 41, one at each corner. The inner ends of the rams 41 in this embodiment carry caterpillar-type tracks 42 which on actuation of the rams clamp firmly against a standard surrounded by the frame. Thereafter, on actuation of the tracks 42, the frame will move up or down the standard and a constant speed can be achieved.

The framework of the embodiments described may be modified so that the holding rams extend outwardly of their frames to enable the carriage to be used within a hollow structure.

Claims

1. A self propelled carriage comprising a framework adapted to locate transversely of an elongate structure, means to propel the carriage along the length of the structure in each direction and means remote from the carriage to control said pressure and propelling means.

2. A carriage as claimed in claim 1, in which the framework comprises a pair of parallel frames longitudinally spaced and interconnected by piston and cylinder means and pressure means comprising a plurality of pressure pads on each frame, each set of pads being releasably engageable against the surface of the structure whereby alternate sets of pads can engage so that the respective frame remains stationary to allow the piston and cylinder means to move the other frame and, by stepwise movements propel the framework.

3. A carriage as claimed in claim 1, in which the framework comprises one frame carrying a plurality of caterpillar type tracks which comprise the pressure means, said tracks being adapted to engage the surface of the structure and remain so engaged to support the carriage thereon or therein and said caterpillar type tracks being also the propelling means whereby continuous movement of the framework along the structure can be achieved.

4. A self propelled carriage substantially as hereinbefore described with reference to Figs. 1 to 4 or Fig. 5 of the accompanying drawings.