GB1566815A - Fire extinguishers - Google Patents

Description

(54) IMPROVEMENTS IN OR RELATING TO FIRE EXTINGUISHERS (71) We, THOMAS GLOVER & CO.

LIMITED, a British Company of Hathershaw, Oldham OL8 3DX, England, do hereby declare the invention for which we pray that a Patent may be granted to us, and the method by which it is to be performed to be particularly described in and by the following statement: The present invention relates to fire extinguishers and in particular to a fire extinguisher operating head.

Conventionally, fire extinguishers are fitted with some form of safety device to prevent accidental or premature activation. These safety devices are usually in the form of pins, clips or detents which have to be moved or detached before the extinguisher can be activated. Additionally, these safety devices are normally fitted with a frangible seal which indicates whether the safety device has been tampered with. However, frangible seals are easily broken accidentally and do not, therefore, provide a wholly reliable guide to the servicability of the extinguisher.

The object of the present invention is to provide a fire extinguisher head with an indicator which is robust and which is visible after operation of the extinguisher to show that the extinguisher is unfit for further use.

According to a first aspect of the present invention there is provided a fire extinguisher operating head comprising an extinguisher operating mechanism which includes an actuating spindle movable against a biassing force to cause extinguisher activation and a hollow lever pivotally mounted on a fixed portion of the head and movable to engage one end of the actuating spindle to move the latter against the biassing force, and an indicator which is normally held concealed in the interior of the hollow lever by abutment against one end of the actuating spindle but which, on movement of the spindle to actuate the extinguisher, is permitted to move into a visible position.

According to a second aspect of the present invention there is provided a fire extinguisher incorporating an operating head according to the first aspect of the present invention.

An embodiment of the present invention will now be described by way of example with reference to the accompanying drawing in which: Figure 1 is a side view of a fire extinguisher operating head which has been partially broken away to reveal the interior thereof; and Figure 2 is a view of the operating head similar to Figure 1 and showing the operating head as it would appear after operation of an extinguisher to which the head had been attached.

The fire extinguisher operating head 1 as shown in the drawing is of the type activated by a squeeze-grip mechanism wherein a pivoted lever is moved towards a fixed lever or handle and thereby causes movement of a spindle carrying suitable opening means for releasing an extinguishing medium contained in the extinguisher.

The head 1 comprises a fixed handle 2 and an operating lever 3 pivotally mounted as shown at 4 to a fixed part of the head 1. The lever 3 is hollow and of channel section and covers a rounded head 5 of an actuating spindle 6. The head 5 abuts an interior surface of the lever 3 and movement of the lever 3 towards the handle 2 depresses the spindle 6 against an opposing biassing force such as a spring (not shown) to actuate a release mechanism (not shown) of a fire extinguisher to which the head is attached. To prevent accidental or premature movement of the spindle 6, an obstructing means comprising a clip 7 is releasably secured to the spindle 6 and prevents movement of same if a force is applied to the lever 3.

Concealed in the interior of the hollow lever 3 is an indicator 8 which is shaped to conform to the channel-section interior surface of the lever 3 and which also pivots on the head 1 at 4. The indicator 8 is provided with an aperture 9, one edge 10 of which aperture 9 rests on the rounded surface of the head 5 of the spindle 6 (as shown in Figure 1) before extinguisher activation and is thereby restrained from falling towards the head 1. The head 5, therefore, forms a detent preventing movement of the indicator 8. The indicator 8 is preferably of a bright colour and may be marked with a suitable inscription, such as "USED", as shown in Figure 2, or "EMPTY".

In operation, the clip 7 is first detached from the spindle 6 so that the lever 3 and concealed indicator 8 can be moved towards the handle 2. Movement of the lever 3 depresses the spindle 6 against the biassing force and at the same time the indicator 8 is carried down to a position where the edge 10 of the opening 9 just clears the rounded surface of the spindle head 5 and drops down on to the upper surface of the head 1. On release of the lever 3 the spindle 6 is urged upwards by the biassing force and forces the lever 3 up to its initial position, leaving the indicator 8 resting on the head 1 in a visible position with the inscription exposed. In this position the indicator 8 cannot be lifted up again to its concealed position inside the hollow lever 3 because the edge 10 of the aperture 9 cannot pass over the head 5 of the spindle 6.

To reset the indicator 8 after operation, it is necessary to insert a tool under the indicator 8 and fully depress the lever 3. The indicator 8 can then be lifted in contact with the interior surface of the lever 3, the edge of the aperture 9 then being able to clear the head 5 of the spindle 6 and ride back to its initial position with the lever 3.

WHAT WE CLAIM IS: 1. A fire extinguisher operating head comprising an extinguisher operating mechanism which includes an actuating spindle movable against a biassing force to cause extinguisher activation and a hollow lever pivotally mounted on a fixed portion of the head and movable to engage one end of the actuating spindle to move the latter against the biassing force, and an indicator which is normally held concealed in the interior of the hollow lever by abutment against one end of the actuating spindle but which, on movement of the spindle to actuate the extinguisher, is permitted to move into a visible position.

2. An operating head as claimed in claim 1, in which the hollow lever is pivotable towards a fixed handle to provide a squeeze-grip operating mechanism.

3. An operating head as claimed in claim 1 or 2, in which the indicator is pivotably mounted on said fixed portion of the head and is provided with an aperture whereby, on activation of the extinguisher, the indicator pivots and is carried by the hollow lever to a position wherein an edge of the indicator defining the aperture clears said one end of the actuating spindle to expose the indicator to view.

4. A fire extinguisher incorporating a fire extinguisher operating head as claimed in any one of claims 1 to 3.

5. A fire extinguisher operating head substantially as hereinbefore described with reference to Figure 1 or Figure 2 of the accompanying drawing.

6. A fire extinguisher incorporating a fire extinguisher operating head substantially as hereinbefore described with reference to Figure 1 or Figure 2 of the accompanying drawings.

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

Claims (6)

**WARNING** start of CLMS field may overlap end of DESC **. movement of the spindle 6, an obstructing means comprising a clip 7 is releasably secured to the spindle 6 and prevents movement of same if a force is applied to the lever 3. Concealed in the interior of the hollow lever 3 is an indicator 8 which is shaped to conform to the channel-section interior surface of the lever 3 and which also pivots on the head 1 at 4. The indicator 8 is provided with an aperture 9, one edge 10 of which aperture 9 rests on the rounded surface of the head 5 of the spindle 6 (as shown in Figure 1) before extinguisher activation and is thereby restrained from falling towards the head 1. The head 5, therefore, forms a detent preventing movement of the indicator 8. The indicator 8 is preferably of a bright colour and may be marked with a suitable inscription, such as "USED", as shown in Figure 2, or "EMPTY". In operation, the clip 7 is first detached from the spindle 6 so that the lever 3 and concealed indicator 8 can be moved towards the handle 2. Movement of the lever 3 depresses the spindle 6 against the biassing force and at the same time the indicator 8 is carried down to a position where the edge 10 of the opening 9 just clears the rounded surface of the spindle head 5 and drops down on to the upper surface of the head 1. On release of the lever 3 the spindle 6 is urged upwards by the biassing force and forces the lever 3 up to its initial position, leaving the indicator 8 resting on the head 1 in a visible position with the inscription exposed. In this position the indicator 8 cannot be lifted up again to its concealed position inside the hollow lever 3 because the edge 10 of the aperture 9 cannot pass over the head 5 of the spindle 6. To reset the indicator 8 after operation, it is necessary to insert a tool under the indicator 8 and fully depress the lever 3. The indicator 8 can then be lifted in contact with the interior surface of the lever 3, the edge of the aperture 9 then being able to clear the head 5 of the spindle 6 and ride back to its initial position with the lever 3. WHAT WE CLAIM IS:

1. A fire extinguisher operating head comprising an extinguisher operating mechanism which includes an actuating spindle movable against a biassing force to cause extinguisher activation and a hollow lever pivotally mounted on a fixed portion of the head and movable to engage one end of the actuating spindle to move the latter against the biassing force, and an indicator which is normally held concealed in the interior of the hollow lever by abutment against one end of the actuating spindle but which, on movement of the spindle to actuate the extinguisher, is permitted to move into a visible position.

2. An operating head as claimed in claim 1, in which the hollow lever is pivotable towards a fixed handle to provide a squeeze-grip operating mechanism.

3. An operating head as claimed in claim 1 or 2, in which the indicator is pivotably mounted on said fixed portion of the head and is provided with an aperture whereby, on activation of the extinguisher, the indicator pivots and is carried by the hollow lever to a position wherein an edge of the indicator defining the aperture clears said one end of the actuating spindle to expose the indicator to view.

4. A fire extinguisher incorporating a fire extinguisher operating head as claimed in any one of claims 1 to 3.

5. A fire extinguisher operating head substantially as hereinbefore described with reference to Figure 1 or Figure 2 of the accompanying drawing.

6. A fire extinguisher incorporating a fire extinguisher operating head substantially as hereinbefore described with reference to Figure 1 or Figure 2 of the accompanying drawings.