A power regulation circuit including an input from an alternating current (AC) power supply, a load element connected to the AC power supply input, a dummy power resistor connected in parallel with the load element, and a controller to dynamically control power to the load element and to the dummy power resistor in response to a variation in the power consumption of the load element.

There is provide a printing apparatus including: a transport section that transports a medium in a first direction; a discharge section that discharges a liquid to the medium transported by the transport section; a signal generation section that outputs a first pulse signal; and a heating section that is provided downstream of the discharge section in the first direction, includes a first heater that generates heat in accordance with a first pulse included in the first pulse signal, and heats the medium, in which the signal generation section adjusts the first pulse in accordance with a heating amount for heating the medium by the heating section.

Power to an electrical device is controlled using a phase control that changes a cutoff phase of an alternating current (AC) electrical signal delivered to the electrical device. The power delivered to the electrical device is increased to an operational level using the phase control. A level of the power delivered to the electrical device is maintained at the operational level using an integral half cycle control that selectively removes a plurality of half cycles from the AC electrical signal delivered to the electrical device such that a plurality of remaining half cycles in the AC electrical signal delivered to the electrical device have a frequency outside a range of sub-harmonic frequencies.

Provided is an image forming apparatus including a temperature sensing circuit to which a temperature sensing element is electrically connected, wherein a surface of a heater on a side where the temperature sensing element is provided is in contact with the inner surface of a film, a heating element is provided in a primary side circuit which is electrically connected to a commercial power supply, and the temperature sensing circuit is electrically insulated from both of the primary side circuit and a secondary side circuit which is electrically insulated from the primary side circuit.

Controlling power delivered to a heating device occurs using a phase control, wherein the phase control includes changing a cut-off phase of an alternating current electrical signal delivered to the heating device. The power delivered to the heating device is increased from zero to an operational level using the phase control. The level of the power delivered to the heating device is maintained at the operational level using both the phase control and an integral half cycle control. The integral half cycle includes selectively removing a plurality of half cycles from the alternating current electrical signal delivered to the heating device.

The present subject matter describes a heating unit. The heating unit comprises a heating element and a controlling unit coupled to the heating element to determine a desired value of a direct current (DC) voltage based on heating element parameters. The desired value is a value of DC voltage desired for operation of the heating element. The controlling unit computes a value of a duty cycle parameter based on device input parameters and the desired value of the DC voltage. The heating unit further comprises a power factor correction (PFC) unit coupled to the controlling unit and the heating element to convert an input alternating current (AC) voltage, received by the PFC unit from an AC supply, to a direct current (DC) voltage of the desired value based on the duty cycle parameter. The PFC unit provides the DC voltage to the heating element.

Provided is an image forming apparatus including a temperature sensing circuit to which a temperature sensing element is electrically connected, wherein a surface of a heater on a side where the temperature sensing element is provided is in contact with the inner surface of a film, a heating element is provided in a primary side circuit which is electrically connected to a commercial power supply, and the temperature sensing circuit is electrically insulated from both of the primary side circuit and a secondary side circuit which is electrically insulated from the primary side circuit.

Disclosed is a heat source for radiating heat onto an intermediate printing material transfer element of a printing apparatus. The heat source comprises a plurality of heat generating segments disposed along an axis, the plurality of heat generating segments including a first heat generating segment, a second heat generating segment and a third heat generating segment. The second heat generating segment is disposed between the first heat generating segment and the third heat generating segment. The second heat generating segment has a length shorter than a length of the first heat generating segment and shorter than a length of the third heat generating segment. Also disclosed is a printing system comprising the disclosed heat source. Also disclosed is a method of selecting a heat radiating pattern of a heat source.

A heating system includes a heater, a switch providing alternating current to the heater, and a current sensor electrically connected between the switch and the heater. The heating system also includes a controller that controls operation of the switch. The controller activates the switch during a portion of a half cycle of the alternating current having increasing amplitude under a threshold. The controller determines, based on a signal received from the current sensor during the activation of the switch, a time period from the start of the half cycle to a threshold timing at which the alternating current reaches the threshold. The controller reactivates the switch at a timing on or after a timing obtained by subtraction of the determined time period from an end of the half cycle. The heating system is useable within an image forming apparatus.

A heating system includes a heater, a current sensor outputting a current monitoring signal indicating a current level of an alternating current power signal, and a switch providing alternating current to the heater. The heating system also includes a controller that controls operation of the switch. The controller activates the switch during a portion of a half cycle of the alternating current power signal having increasing amplitude. Upon the current monitoring signal reaching a predetermined threshold within the half cycle, the controller deactivates the switch. The heating system is useable within an image forming apparatus.