GB2237738A - Apparatus for detecting and venting fumes from a building - Google Patents

Abstract

Apparatus (2) for detecting and venting fumes from a building, which apparatus (2) comprises a window frame (4), a window (6), and a pair of hinges (8, 10) for pivotally mounting the window (6) in the window frame (4), at least one electromagnetic device (12, 14) for holding the window (6) in a closed position, and fume detector means (16) for causing the electromagnetic device (12, 14) to allow the window (6) to pivot to an open position consequent upon the fume detector means (16) sensing fumes in the building, and the apparatus (2) being such that the hinges (8, 10) are substantially frictionless hinges which are so mounted that their pivotal axes (18) are offset from the centre of gravity of the window whereby the window opens solely under the action of gravity when the fume detector means (16) senses the smoke. <IMAGE>

Description

APPARATUS FOR DETECTING AND VENTING FUMES FROM A BUILDING This invention relates to apparatus for detecting and venting fumes from a building.

In United Kingdom patent specification No. 1326112 there is disclosed apparatus for detecting and venting smoke from a building. The apparatus is such that it comprises a window frame, a window, a pair of hinges for pivotally mounting the window in the window frame, an electromagnetic device for holding the window in a closed position, and smoke detector means for detecting smoke and then allowing a pair of springs to push open the window, thereby allowing the smoke to escape and fresh air to enter the building. The apparatus described in UK patent specification No. 1326112 is not entirely satisfactory in that the springs are always biasing the window open against the closing force of the electromagnetic device.

This biasing open of the window can lead to poor sealing of the window and consequent draughts. Furthermore, the springs represent a significant manufacturing cost and they also require installation time to be installed.

It is an aim of the present invention to provide apparatus for detecting and venting fumes, for example smoke, from a building, in which apparatus the above mentioned problems are obviated or reduced.

Accordingly, this invention provides apparatus for detecting and venting fumes from a building, which apparatus comprises a window frame, awindow, a pair of hinges for pivotally mounting the window in the window frame, at least one electromagnetic device for holding the window in a closed position, and fume detector means for causing the electromagnetic device to allow the window to pivot to an open position consequent upon the fume detector means sensing fumes in the building, and the apparatus being such that the hinges are substantially frictionless hinges which are so mounted that their pivotal axes are offset from the centre of gravity of the window whereby the window opens solely under the action of gravity when the fume detector means senses the smoke.

With the apparatus of the present invention, the hinges as used in the above mentioned UK patent specification are not employed. This means that the electromagnetic device can more easily hold the window shut, thus helping to prevent the unwanted ingress of air when the window is closed. Furthermore, the cost of manufacturing and installing the springs is avoided.

Preferably, the hinges include first stop means for arresting the opening of the window at a predetermined position. Preferably, the stop means arrests the opening of the window when the window is open at an angle of 450 to the window frame.

Usually, the first stop means will be such as to require manual re-setting after it has been operated.

Usually, the first stop means will be re-set with a key.

Advantageously, the hinges are manually settable to open the window to 1800 for cleaning and maintenance purposes. In this case, the hinges advantageously include second stop means for arresting the opening of the window in the 1800 position.

Preferably, there are two of the electromagnetic devices. The use of two of the electromagnetic devices gives a more balanced closing action on the window and thus helps to avoid distortion of the window. Preferably, the two electromagnetic devices are positioned one on either side of a top part of the frame, for example one on either side of the transom.

The electromagnetic devices may be any known and suitable electromagnetic devices. They may thus use any known coil and magnet system.

Similarly, the fume detector means may be any known fume detector means for detecting any appropriate fumes such for example as smoke or noxious chemical vapours. Thus, for detecting smoke, a smoke detector means may be used which is a light beam and a photoelectric cell. Alternatively, the smoke detector means may operate on the principle of steady state monitoring such that, when particles are detected in a monitoring chamber, the steady state alters and a switch circuit is triggered.

The apparatus of the invention may be such that there is one of the fume detector means for each window. Alternatively, one of the fume detector means may serve a bank of windows, or all the windows on a floor in a building, or an entire building. The building may be any type of building, for example retail, leisure, municipal, public and office buildings or flats where it is desired to ensure that the building can safely be evacuated in the event of a fire. As will be appreciated, in the event of a fire, smoke on comnunal parts of the building such for example as staircases and landings could hinder or prevent the escape of persons from the building during a fire, and this in turn could lead to loss of life.

An embodiment of the invention will now be described solely by way of example and with reference to the accompanying drawings in which: Figure 1 shows part of apparatus for detecting and venting smoke from a building; Figure 2 is a side view showing the pivotal opening action of the window shown in Figure 1; and Figure 3 illustrates schematically the entire apparatus for detecting and venting smoke from a building.

Referring to the drawings, there is shown apparatus 2 for detecting and venting smoke from a building. The apparatus 2 comprises a window frame 4, a window 6 and a pair of hinges 8, 10 for pivotally mounting the window 6 in the window frame 4. The apparatus 2 further comprises two electromagnetic devices 12, 14 for holding the window 6 in a closed position. The apparatus 2 still further comprises smoke detector means 16 (see Figure D) for sensing smoke.

The smoke detector means 16 is for causing the electromagnetic devices 12, 14 to allow the window 6 to pivot to an open position as shown in Figure 1 consequent upon the smoke detector means 16 sensing smoke in the building. As can be seen from Figures 1 and 2, the apparatus 2 is such that the hinges 8, 10 are substantially frictionless hinges which are so mounted that their pivotal axes 18 are offset from the centre of gravity 20 of the window 6. This means that when the supply of current to the electromagnetic devices 12, 14 is interrupted by the smoke detector means 16, then the window 6 is free to open solely under the action of gravity.

The hinges 8, 10 are such that they each include first stop means 22 for arresting the opening of the window 6 in a predetermined position which, as shown in Figure 1, is such that the window 6 makes an angle of 45 to the window frame 4. The first stop means 22 requires manual re-setting with a key after it has been operated.

The hinges 8, 10 are also such that they include second stop means 24 for allowing the window 6 to be manually opened to 1800 for cleaning and maintenance purposes.

In the open position of the window as shown in Figure 1, smoke inside the building is able to pass through the top aperture 26 in the direction indicated by the arrows 28. Air is able to enter the building through the bottom aperture 30 as indicated by the arrows 32.

The electromagnetic devices 12, 14 each include an electromagnet 34 and a magnetic plate 36. As can be seen from Figure 1, the electromagnets 34 are secured one at either end of a transom 38 forming the upper part of the window frame 4. The magnetic plates 36 are located on the complementary part of the window 6 such that the magnetic plates 36 abut against their electromagnets 34 when the window 6 is closed in the window frame 4. By using two electromagnetic devices 12, 14 instead of one centrally positioned electromagnetic device, any tendency to bow of the window 6 is avoided. The use of the two electromagnetic devices 12, 14, especially without the use of opening springs, ensures that the window C can be tightly shut in the window frame 4 to avoid draughts occuring.

In Figure 3, a bank of three window frames 4 and windows 6 is shown. The windows are shown positioned between a ceiling 40 and a floor 42 of the building. The smoke detector means 16 is shown located on the ceiling 40 and supplied with electrical power via leads 44. The smolie detector means 16 includes an electromagnetic relay 46 which normally operates to hold a pair of contacts closed. when the smoke detector means 16 detects smoke, the electromagnetic relay 46 opens to stop the current supply to the electromagnetic devices 12, 14 via cables 48.

The window 6 thus opens solely under gravity as mentioned above. The window 6 will rotate outwards at the top and inwards at the bottom until its movement is arrested by the first stop means 22. The window 6 will then neither open further nor close until the first stop means is re-set, for example via a re-set device 50. The re-set device 50 is operated with a key in order to prevent unauthorised opening or closing of the window 6.

It is to be appreciated that the embodiment of the invention described above with reference to the accompanying drawings has been given by way of example only and that modifications may be employed. Thus, for example, with excessively tall windows 6, additional electromagnetic devices 12, 14 can be employed to hold the window 6 shut.

These electromagnetic devices can be positioned where desired, for example towards the bottom of the window frame 4 and/or along the sides of the window frame 4.

The window frame 4 can have hollow voids for allowing concealed internal wiring to the electromagnetic devices 12, 14 from junction boxes 52. The window frame 4 may be made from any desired and appropriate materials such for example as extruded aluminium, extruded u PVC, steel, timber or any mixture of these materials.

The window frame 4 may include appropriate sealing gaskets (not shown). The sealing gaskets may be made of rubber or a plastics material.

If permanent trickle ventilation is required to comply with statutory or other requirements, then this may be provided by either penetration through the window frame 4, or by removing some of the sealing gasket material, for example around the glass at the head of the vent, or by adding a vent member or leaving the glass or a vent panel short of the head of the window frame. The manner and type of the venting to be employed may be varied as desired.

A key operated isolating switch may be employed to turn off the electrical supply to the electromagnetic devices 12, 14 for servicing, cleaning or other appropriate purposes. The electrical supply may be turned off to individual electromagnetic devices 12, 14 or to banks of the devices as may be desired.

As will be appreciated, any termination in the electrical supply to the electromagnetic devices 12, 14 will cause the windows 6 to open. The termination in the supply can be the normal working of the apparatus 2 or it can be due to an electrical fault, but in either event, the windows 6 will open to a fail-safe condition. If desired, the electromagnetic relay 46 may be replaced by another switch means such for example as a solid state device or a transducer arrangement which changes an electrical signal to movement and then back to an electrical signal, for example in a system of control where the trigger signal is not a termination in an electrical supply but is an alteration in the signal which triggers an electric sensor for operating holding electromagnets.

The apparatus of the invention may also be used for detecting and venting fumes other than smoke. Thus, for example, the apparatus may be used for detecting and venting to atmosphere noxious fumes from chemical laboratories and chemical stores. In this case, the fume detector means may be a chemical sensor or a gas sensor which, for example, triggers a warning device which in turn triggers a relay causing the apparatus to operate such that the noxious fumes are vented to atmosphere.

Claims (12)

1. Apparatus for detecting and venting fumes from a building, which apparatus comprises a window frame, a window, a pair of hinges for pivotally mounting the window in the window frame, at least one electromagnetic device for holding the window in a closed position, and fume detector means for causing the electromagnetic device to allow the window to pivot to an open position consequent upon the fume detector means sensing fumes in the building, and the apparatus being such that the hinges are substantially frictionless hinges which are so mountedtht teir pivotal axes are offset from the centre of gravity of the window whereby the window opens solely under the action of gravity when the fume detector means senses the smoke.

2. Apparatus according to claim 1 in which the hinges include first stop means for arresting the opening of the window at a predetermined position.

3. Apparatus according to claim 2 in which the first stop means arrests the opening of the window when the window is open at an angle of 450 to the window frame.

4. Apparatus according to claim 2 or claim 3 in which the first stop means is such as to require manual re-setting after it has been operated.

5. Apparatus according to claim 4 in which the first stop means is re-set with a key.

6. Apparatus according to any one of the preceding claims in which the hinges are manually settable to open the window to 1800 for cleaning and maintenance purposes.

7. Apparatus according to claim 6 in which the hinges include second stop means for arresting the opening of the window in the 1800 position.

8. Apparatus according to any one of the preceding claims in which there are two of the electromagnetic devices.

9. Apparatus according to claim 8 in which the two electromagnetic devices are positioned one on either side of a top part of the frame.

10. Apparatus according to any one of the preceding claims in which there is one of the fume detector means for each window.

11. Apparatus according to any one of claims 1 to 9 in which there is one of the fume detector means serving a bank of windows, or all the windows on a floor of a building, or an entire building.

12. Apparatus for detecting and venting fumes from a building, substantially as herein described with reference to the accompanying drawings.