Hewlett-Packard Development Company, L.p.

Hewlett-Packard Company

Mark Hirst

Richard Lee Swantner

Mark Edward Shaw

Brian Christopher Mayer

Brad R Larson

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.

Integral half cycle (IHC) control

In one example, a printer with parallel/serial operational sequencing includes an engine control unit and an image processor unit each coupled to a set of sub-systems. A network unit is coupled to the image processor unit to monitor network packets while the engine control unit, the set of sub-systems, and the image processor unit are in sleep states. When a first predetermined packet is received, the network unit signals with a first modulation signal that the image processor unit is to awaken first before the image processor unit determines whether to awaken the engine control unit and any of the set of sub-systems. When a second predetermined packet is received, the network unit signals with a second modulation signal that the image processor unit, the engine control unit, and a portion of the set of sub-systems are to awaken at the same time.

Parallel/serial operational sequencing

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.

Simultaneous use of phase control and integral half cycle (IHC) control

An electrophotographic imager includes a photoconductive element, a charger, and a light source to expose areas of a charged surface of the photoconductive element to form a latent image. A development element is coupled relative to the photoconductive element to develop, via charged marking agent, the latent image on the photoconductive element. An exposure adjustment factor is selectively applied, prior to the exposing, to a first printable area of the latent image.

Exposure adjustment factor

One embodiment of the present invention provides an apparatus comprising a thermoelectric generator thermally coupled to an assembly having a member, wherein the thermoelectric generator is configured to convert heat from the assembly to an electrical energy. The apparatus further comprises a mechanism comprising a motor configured to actuate the member using the electrical energy.

Apparatus having actuating member

One embodiment of the present invention provides a cooling system in an imaging device having an element that generates heat. The cooling system comprises a thermoelectric generator and a cooling device. The thermoelectric generator is thermally coupled to the element to convert the heat generated by the element to electrical energy. The cooling device is powered by the electrical energy to thereby cool the imaging device.

Imaging device cooling system

An indicating system in a device having a heat emitting member. The indicating system includes a thermoelectric generator and an indicating device. The thermoelectric generator is adapted to thermally couple to the heat emitting member and configured to convert heat from the heat emitting element to electrical energy. The indicating device is powered by the electrical energy and configured to provide indication of when a temperature level of the heat emitting member is above a temperature threshold.

Heat indicating system

In an embodiment of the invention, a circuit for controlling a fusing system such as used in a printer, copier or the like, comprises a timing circuit; an averaging circuit which receives an output from the timing circuit and averages the signal to produce a voltage signal; a modulation circuit arrangement which receives the voltage signal from the averaging circuit and generates a train of pulses which varies with the voltage signal from the averaging circuit; and a switch driver circuit which is responsive to the pulse train from the modulation circuit and which drives a power supply switching circuit with a timing to apply a smoothly changing alternating current to the fusing system. The modulation circuit may be of the pulse width modulation type or the frequency modulation type.

Circuit for controlling a fusing system

A system of the present invention includes an ambient condition sensor for estimating the consumption of toner, developer, or similar printing supply in an electrostatic or ink jet printer. In a preferred embodiment, the ambient condition being monitored is relative humidity, though in other embodiments other indicators of ambient air conductivity or break down voltage are measured. Consumption is estimated by classifying each pixel to be printed according to the number of neighbors of that pixel, accumulating a sum according to each classification, multiplying each accumulated sum by a weight that accounts for its classification, and calculating an overall sum of the weighted products. The overall sum is then scaled by a factor that accounts for the conductivity of ambient air as measured by the sensor to provide an incremental estimate of consumption. The scaling factor is determined by empirical studies. A warning such as 'low toner' is displayed on the printing device and on a remote console when the integrated incremental estimates of consumption surpass a limit.

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Boise, ID, United States of America

Mark Hirst