Regulator for xerographic fusing apparatus

Claim 2

Fusing apparatus for generating a temperature capable of heating thermoplastic particles to a softened state for bonding the particles to the support carrying them with the bonding temperature being attained within a warmup period following a standby period, said apparatus comprising at least one primary electrical heating element arranged to heat the thermoplastic particles on the support, at least one auxiliary electrical heating element adjacent the primary element for assisting in the heating of the particles and regulating means coupled to the primary and auxiliary heating elements for controlling the duration of said warmup period in response to the length of the standby period including memory means for regulating independently the actuation of the auxiliary element and the power level applied to the primary and auxiliary elements during the warmup period.

Claim 3

Fusing apparatus for generating a temperature capable of heating thermoplastic particles to a softened state for bonding the particles to the support carrying them with the bonding temperature being attained within a warmup period following a standby period, said apparatus comprising at least one primary electrical heating element arranged to heat the thermoplastic particles on the support, at least one auxiliary electrical heating element adjacent the primary element for assisting in the heating of the particles and regulating means coupled to the primary and auxiliary heating elements for controlling the duration of said warmup period in response to the length of the standby period including memory means for regulating independently the actuation of the auxiliary element and the power level applied to the primary and auxiliary elements during the warmup period, said regulating means includes bias means for maintaining the temperature of the fusing apparatus at a level below the bonding level.

Claim 4

Fusing apparatus for generating a temperature capable of heating thermoplastic particles to a softened state for bonding the particles to the support carrying them with the bonding temperature being attained within a warmup period following a standby period, said apparatus comprising at least one primary electrical heating element arranged to heat the thermoplastic particles on the support, at least one auxiliary electrical heating element adjacent the primary element for assisting in the heating of the particles and regulating means coupled to the primary and auxiliary heating elements for controlling the duration of said warmup period in response to the length of the standby period including memory means for regulating independently the actuation of the auxiliary element and the power level applied to the primary and auxiliary elements during the warmup period, said regulating means includes bias means for maintaining the temperature of the fusing apparatus at a level below the bonding level.

Claim 5

Fusing apparatus for generating a temperature capable of heating thermoplastic particles to a softened state for bonding the particles to the support carrying them with the bonding temperature being attained within a warmup period following a standby period, said apparatus comprising at least one primary electrical heating element arranged to heat the thermoplastic particles on the support, at least one auxiliary electrical heating element adjacent the primary element for assisting in the heating of the particles and regulating means coupled to the primary and auxiliary heating elements for controlling the duration of said warmup period in response to the length of the standby period including memory means for regulating independently the actuation of the auxiliary element and the power level applied to the primary and auxiliary elements during the warmup period, said memory means includes clock means for generating electrical warmup signals that establish the length of the warmup period and for generating electrical decay signals at the start of a standby period that alter the length of the warmup signals when a warmup period is initiated before a minimum standby period expires.

Claim 6

Fusing apparatus for generating a temperature capable of heating thermoplastic particles to a softened state for bonding the particles to the support carrying them with the bonding temperature being attained within a warmup period following a standby period, said apparatus comprising at least one primary electrical heating element arranged to heat the thermoplastic particles on the support, at least one auxiliary electrical heating element adjacent the primary element for assisting in the heating of the particles and regulating means coupled to the primary and auxiliary heating elements for controlling the duration of said warmup period in response to the length of the standby period including memory means for regulating independently the actuation of the auxiliary element and the power level applied to the primary and auxiliary elements during the warmup period, said memory means includes clock means for generating electrical warmup signals that establish the length of the warmup period and for generating electrical decay signals at the start of a standby period that alter the length of the warmup signals when a warmup period is initiated before a minimum standby period expires.

Claim 7

The apparatus of claim 3 wherein said clock means includes means for generating at least one warm-up siGnal for establishing a time period during which a boost power level above a steady state power level is applied to said heating elements and one warm-up signal for establishing a time period during which the auxiliary heating element is actuated.

Claim 8

The apparatus of claim 3 wherein said clock means includes means for changing the duration of said warm up and decay signals to adjust the fusing apparatus warm up time to obtain a minimum bonding of particles to their support.

Claim 9

Fusing apparatus for generating a temperature capable of heating thermoplastic particles to a softened state for bonding the particles to the support carrying them with the bonding temperature being attained within a warmup period following a standby period, said apparatus comprising, at least one primary electrical heating element arranged to heat the thermoplastic particles on the support, at least one auxiliary electrical heating element adjacent the primary element for assisting in the heating of the particles and regulating means coupled to the primary and auxiliary heating elements for controlling the duration of said warmup period in response to the length of the standby period including memory means for regulating independently the actuation of the auxiliary element and the power level applied to the primary and auxiliary elements during the warmup period, said regulating means includes bias means for maintaining the temperature of the fusing apparatus below the bonding temperature during the standby period and wherein said memory means includes first clock means for generating first and second decay periods defining a minimum standby period and first and second rise periods for defining respective periods during which a boost power level above a steady state power level is applied to the heating elements and during which the auxiliary element is actuated said first and second rise periods being shortened inversely to the duration of said first and second decay periods.

Claim 10

Fusing apparatus for generating a temperature capable of heating thermoplastic particles to a softened state for bonding the particles to the support carrying them with the bonding temperature being attained within a warmup period following a standby period, said apparatus comprising, at least one primary electrical heating element arranged to heat the thermoplastic particles on the support, at least one auxiliary electrical heating element adjacent the primary element for assisting in the heating of the particles and regulating means coupled to the primary and auxiliary heating elements for controlling the duration of said warmup period in response to the length of the standby period including memory means for regulating independently the actuation of the auxiliary element and the power level applied to the primary and auxiliary elements during the warmup period, said regulating means includes bias means for maintaining the temperature of the fusing apparatus below the bonding temperature during the standby period and wherein said memory means includes first clock means for generating first and second decay periods defining a minimum standby period and first and second rise periods for defining respective periods during which a boost power level above a steady state power level is applied to the heating elements and during which the auxiliary element is actuated said first and second rise periods being shortened inversely to the duration of said first and second decay periods.

Claim 11

The apparatus of claim 6 wherein said clock means includes adjustment means to vary said rise and decay periods to obtain optimum bonding of particles to supports after a plurality of standby periods of varied duration.

Claim 12

The apparatus of claim 6 wherein said clock means includes electrical circuits for generating linearly increasing voltages comprising said first and second raise signals and linearly decreasing voltages comprising first and second decay signals and wherein the increasing voltages increase from a reference level to a sense level when the warm up period follows a standby period longer than a minimum standby period defined by said decreasing voltages and wherein said increasing voltages increase from levels of said decreasing voltages to the sense level when the warm up period follows a standby period shorter than the minimum standby period.

Claim 13

The apparatus of claim 8 wherein said clock means includes an operational amplifier having a capacitor and resistor coupled thereto to function as an integrator for generating said increasing and decreasing voltages.