Appliance control circuit

Claim 2

In combination with drying apparatus of the type including a treatment zone through which a stream of temperature conditioned air is directed by air translation means, the improvement of a control circuit comprising: a driving motor means and a presettable timing device in said circuit to control the operation of the apparatus in a preset program; means for conditioning the temperature of the air stream; modulating means for modulating the operation of said temperature conditioning means; and switching means for controlling the operation of said motor means and said modulating means during a drying cycle including manually positionable means for said timing device to select a plurality of timed intervals within a drying cycle and a plurality of contacts coupled to said timing device and selectively operable thereby upon the timing of said intervals, said plurality of contacts including; a first set of normally closed contacts connected between said motor and the power supply, said first set of contacts being opened upon the occurrence of a third interval to terminate operation of the drying apparatus, a second set of normally closed contacts connected between said modulating means and the power supply, said second set of contacts being operable to prohibit energization of said temperature conditioning means upon the occurrence of a second of said intervals, a third set of normally closed contacts connected between said modulating means and said timing device to permit intermittent powering of said timing device via said modulating means during a first of said intervals, said third set of contacts being open during a second of said intervals, and a fourth set of normally open contacts connected between said first set of contacts and said timing device, said fourth set of contacts being closed upon completion of the timing of the first interval to effect a steady energization of said timing device.

Claim 3

The laundry drying apparatus defined in claim 1, wherein said modulating means includes a thermostat device disposed for sensing the temperature of the air directed out of said treatment zone and including contacts which are operable to selectively modulate said temperature conditioning means in accordance with the air temperature sensed thereby.

Claim 4

The laundry drying apparatus defined in claim 1, wherein said modulating means comprises a thermostat including a heat sensitive element having a transfer contact, a contact normally closed to said transfer contact connected to said temperature conditioning means, and a contact normally open from said transfer contact connected to said third set of contacts, said thermostat being disposed adjacent air directed out of said treatment zone and operable in response to the temperature sensed by said heat sensitive element to provide energizing power alternately to said temperature conditioning means and said timing device.

Claim 5

Laundry drying apparatus comprising in combination: a rotatable hollow receptacle for receiving a supply of materials to be dried; a motor coupled to and operable to rotate said receptacle for tumbling laundry therein; means in communication with the interior of said receptacle for providing a flow of heated air therethrough including fan means connected to and driven by said motor to establish said air flow, and means for heating the flowing air including first and second heater elements; and a control circuit for controlling the operation of said motor and said heating means, said control circuit including input terminals for connection to a power supply, modulating means connected in circuit with said input terminals and said heating means and operable to intermittently connect said first and second heater elements in parallel for intermittent energizaton of said first heater element, and timing means connected to said input terminals, to said motor and to said modulating means, said timing means including a manually adjustable timer for establishing a powering circuit for said motor for a timed interval including first contacts interposed between said input terminals and said motor, said timing means being connected to and intermittently operated by said modulating means alternately with said first heater element over a first portion of said interval, second contacts interposed between said timer and said input terminals for establishing a powering circuit for said timer for a second portion of said interval, and third contacts connected in circuit with said heating means and said input terminals for establishing a powering circuit for said heating means for a period less than said timed interval during which period said second heater element is continuously energized.

Claim 6

Laundry drying apparatus comprising in combination: a rotatable hollow receptacle for receiving a supply of materials to be dried; a motor coupled to and operable to rotate said receptacle for tumbling laundry therein; means in communication with the interior of said receptacle for providing a flow of heated air therethrough including fan means connected to and driven by said motor to establish said air flow, and means for heating the flowing air including first and second heater elements; and a control circuit for controlling the operation of said motor and said heating means, said control circuit including input terminals for connection to a power supply, modulating means connected in circuit with said input terminals and said heating means and operable to intermittently connect said first and second heater elements in parallel for intermittent energizaton of said first heater element, and timing means connected to said input terminals, to said motor and to said modulating means, said timing means including a manually adjustable timer for establishing a powering circuit for said motor for a timed interval including first contacts interposed between said input terminals and said motor, said timing means being connected to and intermittently operated by said modulating means alternately with said first heater element over a first portion of said interval, second contacts interposed between said timer and said input terminals for establishing a powering circuit for said timer for a second portion of said interval, and third contacts connected in circuit with said heating means and said input terminals for establishing a powering circuit for said heating means for a period less than said timed interval during which period said second heater element is continuously energized.

Claim 7

A control circuit for controlling the operation of a laundry dryer of the type having a rotatable receptacle for holding and tumbling laundry, motor means for rotating the receptacle and means for providing a flow of air through the receptacle, said control circuit comprising: a power input for connection to a source of electrical energy; timing means including an electrically operated timing device which is manually positionable to select an automatic drying cycle, and a plurality of contacts coupled to said device and operated thereby at timed intervals within the automatic drying cycle; heating means for heating the air flow connected to said power input by a first set of said plurality of contacts which are normally closed upon selection of said automatic drying cycle and opened by said timing device at a second of said timed intervals; modulating means in circuit connected with said first set of contacts and with said heating means and said power input, said modulating means including a heat sensitive element disposed in the air flow to sense the temperature thereof and modulate the energization of said heating means in accordance therewith; a second set of said plurality of contacts being normally closed upon selection of said automatic drying cycle and connecting said modulating means to said timing device, said second set of contacts providing intermittent energization of said timing device by said modulating means, and said second set of contacts being opened by said timing device at the second of said timing intervals; a third of said plurality of contacts being normally closed upon selection of said automatic drying cycle and connected between said power input and the motor means of the dryer, said third set of contacts being operated to an open condition by said timing device at a third interval of said drying cycle; and a fourth set of said plurality of contacts being normally open upon selection of said automatic drying cycle and connected between said timing device and said third set of normally closed contacts, said fourth set of contacts being closed by said timing device upon accumulation during the first interval by intermittent energization to provide continuous energization of said timing device and opened at a fourth interval to inhibit energization of said timing device.

Claim 8

A control circuit for controlling the operation of a laundry dryer of the type having a rotatable receptacle for holding and tumbling laundry, motor means for rotating the receptacle and means for providing a flow of air through the receptacle, said control circuit comprising: a power input for connection to a source of electrical energy; timing means including an electrically operated timing device which is manually positionable to select an automatic drying cycle, and a plurality of contacts coupled to said device and operated thereby at timed intervals within the automatic drying cycle; heating means for heating the air flow connected to said power input by a first set of said plurality of contacts which are normally closed upon selection of said automatic drying cycle and opened by said timing device at a second of said timed intervals; modulating means in circuit connected with said first set of contacts and with said heating means and said power input, said modulating means including a heat sensitive element disposed in the air flow to sense the temperature thereof and modulate the energization of said heating means in accordance therewith; a second set of said plurality of contacts being normally closed upon selection of said automatic drying cycle and connecting said modulating means to said timing device, said second set of contacts providing intermittent energization of said timing device by said modulating means, and said second set of contacts being opened by said timing device at the second of said timing intervals; a third of said plurality of contacts being normally closed upon selection of said automatic drying cycle and connected between said power input and the motor means of the dryer, said third set of contacts being operated to an open condition by said timing device at a third interval of said drying cycle; and a fourth set of said plurality of contacts being normally open upon selection of said automatic drying cycle and connected between said timing device and said third set of normally closed contacts, said fourth set of contacts being closed by said timing device upon accumulation during the first interval by intermittent energization to provide continuous energization of said timing device and opened at a fourth interval to inhibit energization of said timing device.

Claim 9

The control circuit set forth in claim 5, comprising centrifugally operated switch means coupled to the motor means and connected between said heating means and said power input for preventing energization Of said heating means until the receptacle is rotated at a predetermined speed.

Claim 10

The control circuit set forth in claim 5, comprising a door-operated switch including contacts interposed between said power input and the motor and said timing device and operable to prepare a powering path for the motor and said timing device upon closure of a door controlling an opening through which the receptacle is charged and emptied.

Claim 11

The control circuit set forth in claim 5, comprising a relay including a winding and normally open contacts serially connected in circuit with said third set of contacts, and a manually operable switch having contacts connected in shunt relation to said relay contacts and between said relay winding and said power input, the manual operation of said switch energizing said relay to complete the powering circuit to the motor means through said third set of contacts.

Claim 12

The control circuit set forth in claim 5, wherein said heating means includes first and second heater elements connected in parallel relative to said power input and said modulating means is connected in series with said first heater element.

Claim 13

The control circuit set forth in claim 9, wherein said modulating means comprises a thermostat including a heat sensitive element having a transfer contact, a contact normally closed to said transfer contact connected to said first heater element, and a contact normally open from said transfer contact connected to said second set of contacts.