GB2220104A

GB2220104A - Switchbox

Info

Publication number: GB2220104A
Application number: GB8814967A
Authority: GB
Inventors: Barry Gobin
Original assignee: Electrolux Northern Ltd
Current assignee: Electrolux Northern Ltd
Priority date: 1988-06-23
Filing date: 1988-06-23
Publication date: 1989-12-28
Also published as: GB8814967D0

Abstract

A switchbox suitable, for example, for attachment to the handle of a lawn mower, vacuum cleaner, hedge cutter, chain saw or floor polisher, is capable of operation by either rotation or withdrawal of the operating handle 7. The handle is pivoted to one end of a lever 4 operating the switch 2 and also has a slot 9 embracing the pivot pin 5 on which the lever 4 rotates. The lever 4 is rotated and operates the switch either by tilting or withdrawal of the handle. A safety catch 12 may be provided to prevent inadvertent operation. <IMAGE>

Description

SWITCHBOX The invention relates to switchboxes.

Electrically operated appliances, for example lawn mowers, vacuum cleaners, hedge cutters, chain saws or floor polishers, usually have a switch for controlling the motor of the appliance mounted on the appliance handle. Normally the switch is enclosed in a switch box and operated by a protruding lever or operating handle which is pulled or rotated to energise the motor of the appliance, and which switches off power to the appliance as soon as it is released.

It is essential that the operating handle of the switch box should lie in a convenient position close to the handle of the appliance, so that the operator can switch on and off conveniently without releasing his or her grasp of the appliance. Hitherto this has meant that the switchbox has had to be designed in conjunction with the appliance handle, and different types of switch box have been needed for use with different appliances. Moreover, it may be desirable to provide for alternative fixing positions of the switch box to suit operators of different heights or physical characteristics.

An object of the present invention, which is defined in the appended claims, is to provide a construction of switchbox for an appliance which is more versatile, and, in particular, which can be operated equally well by either pulling or by rotating the operating handle.

The invention will be further described with reference to the accompanying drawings, in which Fig. 1 is a simplified view of a switchbox according to the present invention with the cover removed, and Fig. 2 is a partial section through the same switch box taken in a plane at right angles to that of Fig. 1.

Referring first to Fig. 1, the switchbox comprises an outer casing 1 within which is fixed a switch 2, the contacts of which are normally open, but are closed by depressing the spring-loaded plunger 3 of the switch. The switch is operated by means of a cranked leaver 4 pivoted about a pivot pin 5 fixed within the casing 1. The end of the cranked lever 4 which engages the switch plunger 3 is enlarged and rounded, as shown at 6.

The operating handle of the switchbox 7 is in the form of a fairly large loop, so shaped that it will conform reasonably closely to the shape of any of a number of different appliances on which the switchbox may be installed. The inner end of this handle is provided with a slot 9 through which the pivot pin 5 passes and which allows the handle some freedom of movement, and the handle is also pivoted at 10 to the end of the cranked lever 4 remote from the switch. A stop 11 is provided to prevent the handle from rocking about the pivot point 10 without operating the switch, and this stop may conveniently be provided by the edge of the casing 1 where the handle passes into it.

In operation, if the handle is rotated counterclockwise in the view shown in the figure, it rotates the cranked lever, 4 pressing in the plunger 3 and closing the switch. Releasing the handle immediately allows the switch to re-open.

If, instead of rotating the handle, it is pulled outwards, the slot 9 allows it to move for a limited distance, again rotating the cranked lever 4 by reason of its attachment at the pivot point 10, and similarly operating the switch.

To prevent accidental operation of the appliance a safety catch may be provided. This consists of a catch 12 spring-loaded and arranged to slide in a transverse direction. Referring now also to Fig. 2 the catch 12 has a V-shaped lip 13 which, when the handle is in its inner or non-operative position, engages a corresponding lip 14 and acts as a detent to prevent the handle being tilted or withdrawn outwards. Pressure on the safety catch 12 disengages these two lips and allows the switch to be operated.

Claims

1. A switchbox comprising an outer casing fixed within which are a switch and a pivot pin, the switch box also including a lever pivoted on the pivot pin so that-one end bears against the switch to operate it when the lever rotates about the pivot pin, and a handle pivoted to the other end of the lever and having a slot embracing the pivot pin, the slot limiting movement of the handle towards or away from the pivot pin.

2. A switchbox according to claim 1 provided with a stop to prevent the handle from rotating about its pivot point on the lever without operating the switch.

3. A switchbox according to claim 1 or claim 2 provided with a spring-loaded safety catch arranged to prevent operation of the switch until the safety catch has been disengaged.