Abstract: A heater for heating a conductive liquid includes a two-dimensional array of rod-like electrodes (22, 122, 322, 422, 522) extending parallel to one another, an electrical power supply having a plurality of poles, and power switches to connect different ones of the electrodes to different poles so that current flows between the poles through the liquid. The array desirably includes outer electrodes defining the boundary (24, 424) of the array and inner electrodes disposed within this boundary. The array may have regular or irregular spacings between the electrodes. The array can provide numerous different connection schemes to vary the electrical resistance between the poles and thus vary the heating rate. The array can be arranged to provide substantially equal currents through three poles of a three-phase power supply.

Abstract: An ohmic heater for heating a conductive fluid has a plurality of electrodes mounted to a structure with spaces between the electrodes. The electrodes (14) are selectively connect to poles (38, 40) of a power supply, so that some electrodes are connected to the poles and others remain isolated from the poles. Shunting switches are provided for connecting two or more of the isolated electrodes to one another. The shunting switches allow formation of a large number of different connection schemes having a variety of different electrical conduction paths through fluid in the spaces and a variety of resistances between the poles with relatively few electrodes and spaces.

Abstract: A liquid heating system includes an instantaneous heater (18) having an inlet (20) connected to a reservoir (62). The outlet (22) of the heater is connected to fixtures (72) which use the heated liquid, and is also connected through a return connection (30) to the reservoir. In an idle mode, a pump 40 draws liquid from the reservoir (62), so that the liquid circulates through the heater and back to the reservoir. A controller (52) actuates the heater to heat the liquid to a first setpoint temperature, so that the liquid in the reservoir stabilizes at the first setpoint temperature. In a supply mode, some or all of the heated liquid flows from the outlet to the fixtures (72). Cold liquid is admitted from a supply (60) to the reservoir, and cold liquid desirably also is supplied to the heater inlet along with liquid from the reservoir, so that the heater inlet receives a combination of these.

Abstract: An ohmic heater for heating a conductive fluid has a plurality of electrodes mounted to a structure with spaces between the electrodes. The electrodes (14) are selectively connect to poles (38, 40) of a power supply, so that some electrodes are connected to the poles and others remain isolated from the poles. Shunting switches are provided for connecting two or more of the isolated electrodes to one another. The shunting switches allow formation of a large number of different connection schemes having a variety of different electrical conduction paths through fluid in the spaces and a variety of resistances between the poles with relatively few electrodes and spaces.

Abstract: A liquid heating system includes an instantaneous heater (18) having an inlet (20) connected to a reservoir (62). The outlet (22) of the heater is connected to fixtures (72) which use the heated liquid, and is also connected through a return connection (30) to the reservoir. In an idle mode, a pump 40 draws liquid from the reservoir (62), so that the liquid circulates through the heater and back to the reservoir. A controller (52) actuates the heater to heat the liquid to a first setpoint temperature, so that the liquid in the reservoir stabilizes at the first setpoint temperature. In a supply mode, some or all of the heated liquid flows from the outlet to the fixtures (72). Cold liquid is admitted from a supply (60) to the reservoir, and cold liquid desirably also is supplied to the heater inlet along with liquid from the reservoir, so that the heater inlet receives a combination of these.

Abstract: A system and method are provided for applying a desired protective finish to a web of printed label stock. The web of printed label stock is moved through a coating station, where a layer of hot melt varnish is extruded onto the web of printed label stock. Then, the web of printed label stock is transferred to a working station in an environment which causes the layer of varnish to at least partially solidify to a predetermined state as it reaches the working station. At the working station, the layer of varnish is worked to a desired finish. Preferably the web is carried through a nip formed by a pair of rolls, including a highly polished chrome roll which contacts the layer of varnish and works the layer of varnish to a glossy finish. After the layer of varnish is worked to a glossy finish, the web is directed through a finishing station, where the glossy finish is fixed in the layer of varnish, and the web is conditioned to a state in which it can be processed as a web of finished label stock.