Abstract: An inventory monitoring system (10) is provided, which includes a number of merchandise detectors (12) that each include a number of sensors that are configured to detect the presence or absence of products in a predetermined merchandise position, a position on a shelf in a retail space, and to emit a detect signal confirming such presence or absence. Each of the merchandise detectors (12) also includes a rear unit (28) with a transmitter that is connected to the sensor and that transmits the detect signal. The system (10) includes one or more gateway device (36,40) that receives the detect signals from the merchandise detectors (12) and compiles a merchandise data signal from the detect signals, and transmits it a computer (42) to be used in monitoring and managing inventory.

Abstract: A detonator assembly (10) which includes a housing (16), an explosive (20) in the housing (16), an initiating element (32) exposed to the explosive (20), a circuit for controlling operation of the initiating element (32), and a communication arrangement which can establish communication between the circuit and an external controller (60) at least at one optical frequency.

Abstract: A detonator assembly (10) which includes a housing (16), an explosive (20) in the housing (16), an initiating element (32) exposed to the explosive (20), a circuit for controlling operation of the initiating element (32), and a communication arrangement which can establish communication between the circuit and an external controller (60) at least at one optical frequency.

Abstract: A blasting system which includes a control unit, a communications bus which is connected to the control unit, a plurality of detonators which are connected in sequence to the communications bus along its length, and a daisy chain connection between the control unit and the detonators, and wherein, within the sequence of detonators, a first detonator makes use of the daisy chain connection to enable a second following detonator so that data can be exchanged between the control unit and the second detonator using the communications bus.

Abstract: A detonator which, once armed, is automatically disarmed after a predetermined time period in the absence of at least one defined signal during such time period.

Abstract: A lockable shopping cart wheel (10) comprises a plastics hollow casing (12), an axle (22) on which the casing is rotatably mounted and a resetable locking mechanism that is mounted on the axle in the casing. The casing has an end wall (14), a cylindrical wall (16) having a tire (20) and an end wall (18). The locking mechanism includes a locking plate (34) which is axially displaceable but rotationally fixed to the axle (22). A coil spring (38) acts between wall (18) and plate (34) urging it towards wall (14). The plate (34) defines formations which can engage the wall (16) thereby locking the wheel. Between the plate (34) and wall (14) are three gear wheels (44.1), (44.2) and (44.3) which meter the number of revolutions of the casing and release the plate (34) when a predetermined number of revolutions has taken place. The plate (34) is ferromagnetic, allowing the plate to be displaced against the spring action to reset the locking mechanism by using a magnet from outside the casing.

Abstract: A lockable shopping cart wheel (10) comprises a plastics hollow casing (12), an axle (22) on which the casing is rotatably mounted and a resetable locking mechanism that is mounted on the axle in the casing. The casing has an end wall (14), a cylindrical wall (16) having a tyre (20) and an end wall (18). The locking mechanism includes a locking plate (34) which is axially displaceable but rotationally fixed to the axle (22). A coil spring (38) acts between wall (18) and plate (34) urging it towards wall (14). The plate (34) defines formations which can engage the wall (16) thereby locking the wheel. Between the plate (34) and wall (14) are three gear wheels (44.1), (44.2) and (44.3) which meter the number of revolutions of the casing and release the plate (34) when a predetermined number of revolutions has taken place. The plate (34) is ferromagnetic, allowing the plate to be displaced against the spring action to reset the locking mechanism by using a magnet from outside the casing.