GB2030004A - Pendant switch box for control of a machine - Google Patents

Abstract

A pendant switch box for controlling the various movements of a machine has a substantially cylindrical body with an upper part 2 thereof secured to a non-rotatable suspension cable 29 and a lower part 3 serving as a handle and has a first set of switches 13, 14 operated by respective control members such as push buttons 15, 16 disposed at 90 DEG to one another and movable in directions perpendicular to the axis of the cable 29 and corresponding to the horizontal movements required, while second switches 19 for causing raising and lowering movements are actuated by a cylindrical skirt 18 slidable on the upper part 2 and with its lower edge situated adjacent to and between the push buttons. A slidable disc 24 prevents two push buttons being actuated simultaneously. An emergency switch 31 is operable by a push button 32. <IMAGE>

Description

SPECIFICATION Pendant box for control of intersecting movements of a machine The invention relates to a pendant box for the control of intersecting movements of a machine, in particular a lifting apparatus, in which on the one hand each of the switches of a first set of switches is actuated by means of a first control member movable in a direction perpendicular to the axis of a nonrotatable suspension cable and in a direction corresponding to each horizontal movement to be caused, and on the other hand second switches intended to cause movements of rise and fall are actuated by a second control member movable vertically and disposed above the first member.

Such control boxes are particularly adapted to the control of the movements of a lifting hook carried for example by a rolling gantry.

There is already known, for example, from French Patent No. 2129985, an apparatus corresponding to the construction defined above; nevertheless this apparatus has the disadvantage that the first operating member does not permit the operator to place himself in a position which would permit him to accompany the load whilst proceeding in all directions of movement.

This difficulty results particularly from the fact that a bracket supporting the said first operating member creates an obstacle to the arm of the operator. Furthermore the second operating member, as well as the transmission device which couples it to the second switch, has the defect of not being sufficiently protected against atmospheric agents, and of permitting external objects to be able to disrupt its operation.

The invention accordingly proposes to remedy the inconveniences noted above, and furthermore to improve the conditions of use and of safety of an apparatus the general construction of which corresponds to the arrangement mentioned above; at the same time, the invention proposes to provide a control box the constitution of which permits a particularly simplified construction and mounting.

According to the invention this result is achieved by reason of the fact that the box comprises a substantially cylindrical body having an upper portion secured to the suspension cable and a lower portion serving as a handle, and that the first control member comprises four push buttons disposed at 90" each with respect to the other on a region of the body situated between the two portions and movable in a plane perpendicular to the axis of the body, and in that the second control member comprises a cylindrical skirt sliding on the said upper portion and of which the lower edge is situated in the vicinity of the push buttons.

Further features and advantages of the invention resulting from complementary measures will be better apparent from the following description made with reference to the figures of the accompanying drawings, wherein: Figure 1 is a sectional view of the apparatus taken along a vertical axis VV'; Figure 2 is a side elevation of the apparatus; Figure 3 is a sectional view of the apparatus taken on a plane P perpendicular to the vertical axis.

The pendant box forming the subject matter of the invention, and which is secured to the extremity of an anti-rotation suspension cable 29, comprises principally a hollow body 1 of generally cylindrical shape and the axis VV' of which extends, together with the axis of the cable, in a vertical direction under the effect of its own weight, as can be seen in figure 1.

This body comprises an upper portion 2 and a lower portion 3, this latter serving as a handle.

The upper extremity 4 of the upper portion is fixed by means (not shown) to a collar 7 having means 8,8 for coupling it to the lower end 9 of the cable 29.

These means can be similar to stuffing gland sealing members, or can be connected to a fastening clamp such as 12.

A chassis 10 placed at the interior of the body is secured by means of screws 11 or the like to the collar and supports a first set of switches such as 13, 14 intended to close the circuits for control of the horizontal rectangular movements of the apparatus, for example those of a rolling gantry from which the cable would be suspended.

A second set of switches 19 which is likewise fixed on the chassis, but in its region adjacent to the collar, is intended to close the circuits for control of the raising and lowering movements of a hook carried by the rolling gantry in order to perform the lifting of a load.

Finally, a third switch 31 fixed on the lower end 47 of the chassis is intended to be actuated in case of urgency. The body 1 of the apparatus comprises in its central region 6 disposed between the upper and lower portions a series of push buttons such as 15 and 16 which are placed at 90" one from the other on the external surface of the body, and which are movable in a plane P perpendicular to W'.

These push buttons, which are four in number, for the control of four horizontal movements, could be less in number if certain movements were not necessary.

The surfaces 27 and 28 for transmission of the movement of the buttons shown are placed directly opposite to the switches 13 and 14 for causing their change of state. An intermediate system of rods could likewise be disposed between said buttons and the switches if a particular disposition of the latter made direct actuation impossible.

In order to avoid the simultaneous accidental actuation of two push buttons, a disc 24 is placed on a slide member 25 of the chassis and slides thereon by means of a plate 30 to which it is coupled. This disc is placed between the surfaces for transmission of movement, such as 27 and 28, as can be seen in figure 3, and thus constitutes a simple and effective locking device.

The upper portion 2 of the body is surrounded by a cylindrical skirt 18 which can slide along the same in vertical directions, to one side and the other of a central rest position, in order to serve as the control member 44 for the second switches.

A first groove 22 formed in the upper portion of the body parallel to W' permits the passage of an actuating finger 20 which is carried by the internal surface 35 of the skirt and which extends as far as the second switches 19 which it must operate.

The rest position of the skirt, which corresponds to non-actuation of the switches 19, is assured by a return device which can be constituted, by way of non-limiting example, by a spring 37 which can be compressed parallel to W' and the ends of which abut, on the one hand, on the stops 38,39 fast with the body 1 or with the chassis 10 and on the other hand, on the tenons 40,41 placed on the internal surface of the skirt.

The cooperation between these stops, these tenons and this spring is obtained by means of a second groove 36 which is traversed by the said tenons and which forms a housing for said spring. In an obvious modification, the spring could be placed between the external surface of the upper portion and the internal surface of the skirt.

In order to permit a simultaneous actuation of one of the first and one of the second switches, the lower region of the skirt at 21 is extended by milled portions such as 33,34 which extend below the push buttons in the angular sectors disposed between them.

The recesses of the skirt, such as 42 and 43, which surround the push buttons as well as the milled portions 33,34 further contribute to assuring protection against the accidental actuation of the push buttons.

Furthermore, to ensure that the skirt cannot be actuated accidentally and that the play essential for its sliding movement does not permit passage of external liquid or powdery materials, a cylindrical cap 23 extends externally about the upper part 45 of the skirt; this cap is advantageously secured by means of screws such as 46 on the collar 7.

A push button 32 can be placed at the lower end 5 of the handle for carrying outthe actuation of the safety switch 31.

Apart from the advantages of simplicity and security of handling, this control box has further not only the advantage of permitting easier manufacture and assembly of its various elements in the factory, but also extreme facility of mounting and attachment on the end of the suspension cable.

Claims (8)

1. A pendant box for the control of intersecting movements of a machine, of the kind in which each of the switches of a first set of switches is operated by means of a first control member movable in a direction perpendicular to the axis of an anti-rotation suspension cable and in a direction corresponding to each horizontal movement to be made, and in which second switches for causing movements of raising and lowering are actuated by a second control member movable vertically and situated above the first member, characterised in that the box comprises a substantially cylindrical body having an upper portion secured to the suspension cable and a lower portion serving as a handle, and in that the first control member comprises four push buttons disposed at 90 one from the other on a region of the body situated between the two portions and movable in a plane perpendicular to the axis of the body, and in that the second control member comprises a cylindrical skirt sliding on said upper portion and of which the lower edge is situated adjacent to said push buttons.

2. A pendant box, as claimed in claim 1,wherein a cylindrical cap fast with the upper portion surrounds the upper portion of the cylindrical skirt, and wherein the lower edge of said skirt extends below the push buttons in sectors placed between the said buttons.

3. A pendant box, as claimed in either of claims 1 and 2, wherein the first switches actuated by the push buttons and the second switches actuated by the skirt are mounted on a chassis situated at the interior of the body and to which it is coupled by a collar which also supports the cap.

4. A pendant box, as claimed in claim 3, wherein the upper portion of the body has a slot parallel to the axis of the body through which extends movably a coupling element acting between the skirt and the second switches.

5. A pendant box, as claimed in claim 3, wherein said collar comprises means for attachment to the lower end of the suspension cable.

6. A pendant box, as claimed in claim 3, wherein a safety switch, mounted on the lower end of the chassis, can be actuated by a third operating member disposed at the lower part of the handle.

7. A pendant box, as claimed in claim 3, wherein at each side of a horizontal plane normal to the axis of the body there are disposed respectively the first switches and a locking device constituted by a disc which is movable in a second plane parallel to said first-mentioned plane and which is disposed between surfaces for transmission of movement of the push buttons.

8. A pendant box, for the control of intersecting movements of a machine, substantially as described herein with reference to the accompanying drawings.