Field of the Invention

The present invention relates to a trapdoor safety device, in particular a safety device for warning passers-by of the presence of an open trapdoor.

Background

Increasing interest and awareness of health and safety is a factor in many societies and in many premises, commercial and residential.

Trapdoors are used in many premises, between floors and/or in flooring.

Lack of awareness of a trapdoor can be potentially very hazardous to a passer-by or any person in the vicinity of the trapdoor.

In many circumstances a light is provided to illuminate the area around the trapdoor. Rather than have the light permanently switched on, the light may require manual activation and manual deactivation to avoid energy wastage. In an attempt to minimise risk of the trapdoor being left open and not seen, automatic light switches may be provided which are rigged to trapdoors and switch on when the trapdoor is open. However, this does prevent the risk presented to anyone in the trapdoor vicinity and in particular those who are not familiar with the area or even aware of the existence of the trapdoor. In such cases, the activation of a light may not provide sufficient or suitable warning of the presence of a trapdoor.

Prior Art

Chinese patent application CN-A-205 692 305 (XUE) discloses a safety warning device based on an electro-optical distance measurement (EDM).

Korean patent application KR 2014 0 002 669 (Yoon) discloses a fall protection device designed for a manhole. US patent US 5 554 972 (BYRNE) discloses apparatus and a method to provide an electronic perimeter warning system to prevent the ingress or egress of persons or machines from a selected area.

Korean patent application KR-A-20100022651 (YOO) discloses a manhole cover device with a lamp is provided to prevent accidents. The lamp illuminates an area around a manhole. A controller is connected to a battery, and controls power supplied to the lamp. A solar battery charges the battery.

Chinese patent application CN-A-105139561 (GAO) discloses a manhole cover inclination alarm device which comprises an angle sensor which is used for detecting an inclination angle of the manhole cover. A microprocessor is connected to the sensor. When the angle sensor detects that the manhole cover is inclined to a pre set angle, the inclination sensor causes an alarm to be generated.

Chinese utility model CN-U-205 247 560 (WANG) discloses a motor-driven lid for a manhole cover for use on highways. An LED lamp has a control means which switches on a warning light in poor weather or low visibility.

Chinese utility model CN-U-20896559 (CHEN) discloses an intelligent man hole lid which has a first controller, a manhole cover, a magnetic switch and a second intelligent controller. A plurality of lamp grooves are formed in the well lid base. A liquid level sensor and an antenna are arranged to communicate via the internet of things (IOT) if the intelligent manhole cover is stolen or opened and a red-blue double-flashing LED lamp flashes to warn pedestrians and vehicles passing by.

Chinese patent application CN-A-104464134 (ZHANG) discloses a well lid alarm system. The alarm system comprises a well lid seat ring, an outer cover for sealing the well lid seat ring that is arranged on the upper portion of the well lid seat ring, and an inner cover which is arranged in the well lid seat ring. The inner cover is provided with a groove for containing a sealed waterproof box. At least two symmetric glass containers are obliquely arranged in the sealed waterproof box and a mercury tilt switch detects inclination of the inner cover. When the lid is an alarm is triggered.

Chinese utility model CN-U-203588401 (LIU) discloses a manhole cover monitoring and alarm system which includes a manhole cover body. The lower surface of the manhole cover body is provided with a drive plate and a control box. A mercury switch is arranged on the drive plate quite conveniently and triggers when the manhole cover is stolen or moved. The control box transmits an alarm to a remote monitoring centre.

The present invention arose in order to overcome problems suffered by existing devices.

Summary of the Invention

According to a first aspect of the present invention there is provided a trapdoor safety device comprising: a tilt sensor which in use is attached to an underside of a trapdoor; the tilt sensor is connected to a controller which receives a signal from a proximity sensor; also connected to the controller are a light source and an alert mechanism; the tilt sensor is operative, when the trapdoor is opened, to switch the proximity sensor from a quiescent state to an active state, so that the proximity sensor is operative to detect a proximity event, upon detection of a proximity event the controller receives the signal and causes the light source to illuminate the trapdoor and/or a trapdoor opening and activate the alert mechanism.

In this way the trapdoor safety device becomes automatically active; that is switched from a quiescent to a non-quiescent or an active state. Therefore when the trapdoor is opened, even by a very small amount, the tilt sensor detects that the trapdoor has been displaced from its closed state or orientation and alerts the proximity sensor by causing it to be switched to a non-quiescent state. In this the alert mechanism is activated when a trapdoor securement means is damaged or partially opened. Only when the trapdoor is properly closed and secured, may the trapdoor safety device be switched to a dormant or quiescent state.

It is appreciated that the term ‘trapdoor’ may refer to any opening in a floor or ground that has a cover or a hatch or manhole cover.

In some embodiments the device may be housed within a single unit. The single unit may be arranged on or near to the trapdoor and include wireless means which communicates with a proximity sensor which in some embodiments may be located outside the housing. In other embodiments the device may comprise a plurality of components or units in communication one with another wirelessly or connected by hard-wiring, or a combination of wireless and hard wired connections.

For example, in some embodiments the single unit may be adapted to be hung, stuck to or fixed to an underside of a trapdoor. In another embodiment the safety device may be integrated with the trapdoor or frame in which the trapdoor is located.

In some embodiments the trapdoor comprises a securement means that securely closes the trapdoor and prevents opening until the securement means is unlocked or displaced which is authorised upon receipt of an authorisation command which may be transmitted from a wireless transmitter in the device.

The securement means may comprise a holster. The alert mechanism may be activated when the trapdoor securement means is authorised so that it can be unlocked or displaced. This may be performed manually or by way of an automatic actuator when commanded. Alternatively, should the securement means become compromised, for example become damaged, the alert mechanism may issue a warning signal or alarm indicating that the safety device is damaged and may not be functioning.

For example, the holster may receive at least one bolt in order to secure the trapdoor, and the bolt may include a bayonet which is adapted to turn within the holster and engage therein in order to secure the trapdoor. An actuator, which operates the bolt, in the holster, may be connected wirelessly or by a hardwire connection to the alert mechanism. Movement of the bolt within the holster, or out of the holster, thereby the causes the alert mechanism to be activated. In this way users and anyone in the surrounding area of the trapdoor is alerted to the danger of a trapdoor being open or a faulty trapdoor securement means.

In some embodiments the single unit, which encloses the device, may be envisaged to be adapted to be displaceable from the underside of the trapdoor, for example for maintenance, upgrade or battery replacement. In some embodiments it may be envisaged that the unit is adapted to be secured in a correct orientation on the trapdoor, such that the light source, for example, is correctly directed in use.

The unit may be connected to the trapdoor by a twist lock or a bayonet securement means, for example wherein the unit is placed and turned to secure the unit on the trapdoor. In this way the unit can only be fitted in a selected orientation which may be important when opening so as not to damage it against adjacent furniture or fittings.

The proximity event may be envisaged to relate to a person being detected when passing or being in the vicinity of the trapdoor. When the trapdoor is open and the safety device is switched to an activate state, any time that a proximity event is detected the safety device is operative to generate an alert and/or activate a light. It is appreciated that the safety device may be programable to select the type of alerts, for example audible and/or visible, and the option to switch on a light to illuminate the area and/or a space below the trapdoor.

In some embodiments the light may include a sensor that detects level of light so that the light is only activated in low light levels or darkness.

The tilt sensor is operative to switch the proximity sensor to a quiescent state when the trapdoor is closed so as to avoid false indications of a proximity event. This prevents activation of the alerts and/or light when the trapdoor is closed.

In some embodiments the alert mechanism comprises an audible alert. For example the device may comprise a loudspeaker, such that the alert is broadcast to the surrounding area thereby alerting passers-by audibly and upon detection of their presence.

In some embodiments the alert mechanism comprises a visual alert. In addition or as an alternative, for example the device may comprise a flashing light or series of lights that are lit in sequence or that strobe. It is appreciated that the light used may be a dedicated and independent light from the light source which illuminate the area. Preferably the proximity sensor emits an electromagnetic field or a beam of electromagnetic radiation and detects changes in the field or in a reflected signal. In some embodiments the proximity sensor may comprise an optical sensor.

In some embodiments the proximity sensor comprises an infrared (IR) sensor or passive infrared (PIR) sensor.

In some embodiments the proximity sensor comprises a radio frequency (RF) sensor.

In some embodiments the tilt sensor is operative to activate other electronic elements.

In some embodiments the energy source comprises a battery supplying electric current to at least one of and preferably all of: the proximity sensor, the light source, the alert mechanism and the tilt sensor. In other embodiments the energy source may comprise a mains electricity supply.

The device may comprise a timer, clock or timing means. In this way in some embodiments the device comprises a sleep mode, or low-power mode, which may be entered after no activity has been detected by the proximity sensor for a set or predefined period of time or at user specified times. The proximity sensor may be enabled to switch the device to an operative mode, so as to enable the light source and/or the alert mechanism to operate.

In some embodiments the light source comprises a lens, which may be arranged to direct the light source and/or to enhance the light source. Alternatively the lens may diffuse or spread light from the light source at a low level around the trapdoor, so as to avoid dazzling passers-by. This controlled level of lighting also ensures that lighting of the area around the trapdoor is adequate to indicate clearly the trapdoor opening.

The lens may be combined with, or have associated therewith, one or more reflectors. The, or each, reflector is ideally arranged to reflect and/or direct light in use, so as to alert anyone in the vicinity of the trapdoor or people who are passing- by. In some embodiments several light sources may be disposed around the trapdoor. For example the light source may comprise a plurality of lights or light emitting diodes (LEDs), arranged around the trapdoor entrance, for example around its perimeter.

The light source(s) may be operated in response to a signal from the proximity sensor. For example, they may be switched to change colour and/or flash on and off in sequence and/or switched to become brighter, upon receipt of a signal indicating proximity of a passer-by.

In some embodiments the tilt sensor is operative to activate and deactivate the proximity sensor. In this way the tilt sensor controls when the proximity sensor is active or dormant (quiescent) so that when the trapdoor is closed, and the tilt sensor detects and indicates that the trapdoor is closed, the device is not operative to detect proximity of passers-by as the safety device is in a quiescent state or hibernation mode.

It is appreciated that the light source may not automatically switch off upon closure of the trapdoor but is arranged to remain illuminated for a pre-selected time after closing of the trapdoor as a courtesy light. This allows time for a user to lock and check the trapdoor and to vacate the area whilst it is remains lit. The safety device may include a timer means that overrides the switching off the light source in order to achieve this.

In some embodiments the tilt sensor communicates with the proximity sensor by way of a wireless communication device, such as Bluetooth (RTM) transmitter. In some embodiments the tilt sensor communicates with the alert mechanism by way of a wireless communication device, such as Bluetooth (RTM) transmitter.

In some embodiments the tilt sensor communicates with the light source by way of a wireless communication device, such as wireless transmitter which operates in accordance with Bluetooth (RTM) protocol.

In some embodiments the safety device has a transmitter that is operative to transmit a signal to a remote electronic device, such as a smartphone or tablet, or to a monitoring network, in order to indicate status of the trapdoor. For example, when the trapdoor is opened, and during the period it remains open, a status signal may be repeatedly transmitted until the trapdoor is closed. If suspected damage is detected, for example if the securement means is compromised, a warning signal is transmitted.

In this way a user is able to monitor the status of the trapdoor remotely, for example on a personal computer, smartphone, tablet or on a portable wireless electronic device.

A preferred embodiment of the invention will now be described by way of example only and with reference to the Figures in which:

Brief Description of Fiqures

Figure 1 shows an isometric view of an embodiment of the device according to the present invention;

Figure 2 shows a reverse isometric view of the embodiment of the device shown in Figure 1 ;

Figure 3 shows an exploded isometric view of the embodiment of the device shown in Figure 1 ;

Figure 4 shows a reverse isometric view of the embodiment of the device shown in Figure 1 ;

Figure 5 shows a view of a second embodiment of the device according to the present invention; and

Figures 6A and 6B show an alternative embodiment of the invention with a light fitted above a trapdoor.

Detailed Description of Figures

With reference to the Figures there is shown an embodiment of the device generally comprising a safety device 99 arranged to secure to an underside of a trapdoor (shown in Figure 6). The device 99 comprises a trapdoor securement means which includes a holster 299, an electrical energy source (not shown), a proximity sensor 2, a light source 64, 66, a two part alert mechanism 17, 64 and a tilt sensor 7, wherein the proximity sensor 2 is arranged to detect proximity of a passer-by to the trapdoor and activate the alert mechanism to provide an alert of this proximity, the light source 66 is arranged to illuminate the trapdoor; and the tilt sensor 2 is arranged to deactivate the proximity sensor.

In particular reference to the pictured embodiment the embodiment comprises an octagonal device 99, comprised of a device unit 199 and a holster 299 adapted to secure to the underside of the trapdoor.

The unit 199 comprises an octagonal unit arranged to be located onto and secured on the underside of the trapdoor through a plurality of screw holes.

A bayonet mechanism, comprising bayonet slots 29 in a wall 9 and bayonet studs 30 projecting from the unit sides. The wall 9 fits inside the sides of the unit hidden by the outer sidewalls 8 of the unit.

A translucent or transparent lens 1 is arranged above the sidewalls 8 of the unit, having a flat top and eight substantially orthogonal panels between the top and unit sidewalls 8.

The octagonal panels of the lens extend substantially parallel the outer sidewalls of the unit, and cover over eight reflectors 6, which comprise frustoconical reflective portions with a light source 64, 66 at the base of each cone. These light sources are light emitting diodes (LEDs).

One of the reflectors comprises a white LED 66 at the base of the cone. The other reflectors comprise orange LEDs 64 at the base of the cones. The lens 1 is made from polycarbonate and is tough in order to protect internal components of the device. Ribs or lenticules on the lens 1 help disperse light from the white and orange LEDs. In particular upright ribs 38 disperse or spread white light source 66 to either side of the trapdoor and device.

A PIR (passive infra-red) sensor 2 is located centrally on the device below the lens 1 in the first embodiment and near the top end of the device in use extending from the lens in the second embodiment. The sensor 2 detects infra-red radiation from objects in its field of view and detects when a passer-by is walking too close to the device and/or trapdoor, even when the surrounding environment is dark.

When activated the light sources 64, 66 such as flashing light and audible alert is switched on to warn passers-by of a potential hazard.

A PIR sensor PCB 4 (printed circuit board) holds the sensor in position and connects to a main PCB 7 below

The orange LED light sources 64 flash in 7 directions when the PIR sensor is triggered, visually alerting people of the trapdoor. The white LED 66 turns on when the device is detected by the tilt sensor to be vertical, illuminating the trapdoor opening below, so the danger is visible in low light. The light is directed to a region surrounding the trapdoor opening.

The reflectors 6 direct the light from LEDs outwards, away from the device and are made from vacuum metallised polycarbonate.

A reflector bracket 5 and cover 3 hold the reflectors and LEDs securely in place and is made from sheet metal.

The audible alert 17 comprises a loudspeaker which activates when the PIR sensor is triggered and sounds an alarm and will also beep when the batteries are running low on power.

The main PCB and control means control all of the electronic components and the tilt sensor which turns off electronic components of the device when in a quiescent state or sleep mode when in a horizontal position i.e. when the trapdoor is closed. In this way a user may be enabled to allow the tilt sensor to activate and deactivate the proximity sensor and/or energise the light sources.

In the pictured embodiment when the tilt sensor is vertical (i.e. trapdoor open) the tilt sensor activates the white downward facing LED and puts the alarm into standby mode or non-quiescent state. The unit sidewalls are made from injection moulded polycarbonate for impact resistance and UV stability. The unit sidewalls 8 and the holster 299 comprise vents 22 for release of sound from the alert loudspeaker 17.

The unit holds three AA batteries under a battery cover 18 with a rubber seal to protect from water and dirt ingress into the base 31 of the unit. The lens 1 is screwed onto the sidewall at plural screw clips 23.

The unit is adapted to be mounted to the underneath of a trapdoor using multiple screw fixings 33 and bayonet so the unit so the unit can easily be removed to replace the batteries.

Referring to Figures 6A and 6B, which show an alternative embodiment of the invention, a light 150 is fitted above a trapdoor 100. When the trapdoor is closed it lies flush with floor 120. The trapdoor 100 is connected to the floor 120 by way of a hinge 190. Unit 110 is attached to an underside of the trapdoor 100. When the trapdoor 100 is opened, by throwing bolt 160 and releasing it from catch 170, the trapdoor is able to open on hinge 190 in the direction of arrow A.

Referring to Figure 6B the situation is shown where the trapdoor 100 is opened. When this occurs the unit 110 switches from a quiescent mode to an active mode and a signal is transmitted from Bluetooth transmitter 120 to a Bluetooth receiver 140 which communicates with light 150. This results in the light 150 illuminating the area around the trapdoor 100 so as to show the opening and so indicates the risk of falling into the opening to passers by.

The invention has been described by way of examples only and it will be appreciated that variation may be made to the above-mentioned embodiments without departing from the scope of invention as defined by the claims.