Abstract: A thermal printer for printing on paper (26), the printer comprising a thermal print head (2) that co-operates with a paper drive roll (15) by bearing thereagainst, in which the print head is carried resiliently by a fixed chassis portion (1) while the drive roll (15) is carried by a moving chassis portion (13) hinged to the fixed chassis (1) and forming a cover giving access to the compartment in the printer for containing the roll (12) of paper, characterized in that, when the cover is closed, the zone of contact between the paper drive roll (15) and the row (4) of heating points of the print head (2) is situated above the diameter (14) of said roll that passes through the hinge between the moving chassis (13) and the fixed chassis (1).

Abstract: A recording device for recording impressions made by a transfer thermal printer, the device comprising a transfer film paid out from a roll and taken up by a drum, the roll and the drum being disposed inside a cassette having a side wall including a setback defining a print zone, wherein the cassette includes a read window other than the print zone, guides designed to impose a path on the transfer film such that the transfer film passes the window between the roll and the drum, and a support for a contrast surface.

Abstract: A thermal print head including a line of electrically resistive heating points and electronic controls for controlling sequential connection to a power supply providing electrical current, and including for each heating point a countdown register which is loaded prior to printing each line of points with a value corresponding to the length of time during which a connection should be maintained with the corresponding heating point starting from a print authorization instant common to all of the points. According to the invention, the print head includes sensors for sensing the resistance of each heating point in real time, which sensors are connected to a circuit for regulating the amount of energy actually supplied to the corresponding point.

Abstract: A device for registering the printing performed by a thermal transfer printer, wherein it is constituted by the film carrying the transfer ink after it has passed over the heating points of the print head and onto a film take-up spool that includes means enabling it to be coupled to a drive member synchronized with a drive member for driving the print medium.

Abstract: An electrical measuring device utilizing a shunt, an electronic measuring circuit floating at the potential of the shunt and a first voltage divider connected between the shunt and a neutral point to provide a first voltage signal to the circuit. To obtain the benefit of decoupling the potential between the shunt and the intermediate point of the first voltage divider, the device includes an additional terminal connected to the shunt by a second voltage divider, whose intermediate point supplies a second voltage signal used differentially with the first.

Abstract: A multi-rate commodity metering system comprises an electronic key containing an EEPROM, and a meter for metering the commodity and having a receptacle for receiving the key. The meter also contains a real-time clock. The key can operate as a prepayment device, a programming device and a meter-reading device. Thus the key is taken to the commodity suppliers premises, where, in return for a payment, a credit signal representative of the payment is stored in the key. At the same time, a new program for the meter, i.e. new times for switching between rates and new prices per unit of commodity for each rate, together with the date and time at which the new program is to come into operation, can also be stored in the key. Then, when the key is inserted in the receptacle in the meter, the payment signal and the new program are entered into the meter. Additionally, the current set of meter readings (i.e., the respective readings for each rate) are read into the key, along with the date and time.

Abstract: An electronic token for use with a prepayment commodity meter such as an electricity meter comprises a key-like device 10 having a head 12 containing an electronic circuit and a body portion 14 for insertion into a keyway in a receptable 40 in the meter. The body portion 14 has grooves 24 which serve to guide the body portion into the keyway, and which contain electrical contacts 28, 30 connected within the device 10 to the electronic circuit. Between the body portion 14 and the head 12, the device 10 is provided with a locating recess 27, which engages a projection 78 in the receptacle 40 when the body portion is fully inserted into the keyway. The receptacle 40 incorporates a combined shutter 98 and spring 102, which serve to close the keyway in the absence of the device 10, and to urge the body portion 12 to one side of the keyway during insertion, such that the recess 27 engages the projection 78 and the contacts 28, 30 engage contacts 68, 72 in the receptacle.