Abstract: A method of regulating the valve of the resistance of a thick film resistive element. The resistive element comprises a resistive film (25) which bears on its edge two connection terminals (21, 22) and a connecting bar (24). The variation of the resistance is obtained by forming a slot (23) between the terminals, the slot being substantially perpendicular to the connection bar which connects the two parts of the resistive film separated by the said slot.

Abstract: A high tension generating and distributing device includes a plurality of secondary windings 11, 12, connected to associated ones of the spark plugs of an internal combustion engine, these secondary windings being mounted on a single magnetic frame 1, 2 offering a plurality of flux paths through a low tension primary winding 7 or 8, each of these flux paths being associated with one of the secondary windings 11, 12 and with means, for example in the form of flux gaps 3, 4, 5, 6 or auxiliary windings 213, 214 having associated therewith shunt switches 215, 216, for limiting or cancelling the magnetic flux in some of the flux paths so as to leave one flux path with a higher rate of change of flux than the attenuated rate of change of flux in the other flux paths, thereby selecting the secondary winding associated with the non-attenuated flux path as the one in which the high tension current is to flow.

Abstract: An air conditioning device for an automobile vehicle includes the provision for automatic proportional control of the air conditioning function and also a priority function such as vehicle windscreen demisting or defrosting. Economy of pneumatic power is achieved by providing, with a double threshold control system, a signal for operating pneumatic flow distributors in the driving fluid lines to pneumatic jacks driving the control elements of the air conditioning device by means of an electrical signal which is capable of being either continuous or discontinuous in which latter state the flow distributor to which the discontinuous signal is applied is caused to oscillate to achieve an intermediate pneumatic pressure between pressure values corresponding to fully open and fully closed positions of the air conditioning control elements to be manipulated.

Abstract: An air conditioning device for an automobile vehicle includes the provision for automatic proportional control of the air conditioning function and also a priority function such as vehicle windscreen demisting or defrosting. Economy of pneumatic power is achieved by providing, with a double threshold control system, a signal for operating pneumatic flow distributors in the driving fluid lines to pneumatic jacks driving the control elements of the air conditioning device by means of an electrical signal which is capable of being either continuous or discontinuous in which latter state the flow distributor to which the discontinuous signal is applied is caused to oscillate to achieve an intermediate pneumatic pressure between pressure values corresponding to fully open and fully closed positions of the air conditioning control elements to be manipulated.