Pushbutton hand dryer timer and method

• US 6,295,410 B1
• Filed: 02/07/2000
• Issued: 09/25/2001
• Est. Priority Date: 02/07/2000
• Status: Expired due to Fees

• Current Assignee: France/Scott Fetzer Company
• Original Assignee: France/Scott Fetzer Company
• Inventors: Helms, Valerie, Livers, James D. Jr.
• Primary Examiner(s): Jeffery, John A.
• Application Number:
  US09/499,130
• Time in Patent Office: 596 Days
• Field of Search: 392/381, 392/380, 392/370, 345/63, 345/64, 34/90, 342/02, 219/492, 219/493, 219/507, 219/509, 200/38.R, 200/38.A, 200/38.F, 200/38.FA, 200/38.FB, 200/38.B, 200/38.BA, 200/38.C, 200/38.CA, 200/38.E, 200/39.R, 200/39.A
• US Class Current: 392/381
• CPC Class Codes: A47K 10/48 Drying by means of hot air hair-drying devices A45D20/00; curative hot-air baths A61H33/06; electric heating elements H05B
• CPC Class Codes: H01H 43/00 Time or time-programme switches providing a choice of time-intervals for executing one or more switching actions and automatically terminating their operations after the programme is completed

Abstract

A hand dryer timer having a switch in electrical communication with, and controlling the operation of a heater, a fan motor and a timer motor which are electrically connected to two nonneutral lines of a power source. A cam is mounted on a drive shaft of the timer motor such that the cam rotates with the drive shaft and also slides longitudinally over the drive shaft. The cam has a cam lobe adjacent an actuating arm of the switch. A biasing element is located between the timer motor and the cam and biases the cam to a first position aligning the cam lobe with the actuating arm of the switch. The switch includes two sets of switch contacts in a power circuit for the heater and fan motor, so that at the end of a drying cycle, the two sets of switch contacts are effective to electrically isolate the heater and fan motor from both non-neutral lines of the power source.

Claims

1. A hand dryer operable with first and second nonneutral power wires having a voltage potential therebetween, the hand dryer comprising:

a heater operatively connected to the voltage potential;

a fan motor operatively connected to the voltage potential;

a timer motor operatively connected to the voltage potential;

a first switch operated by the timer motor having a first side electrically connected to the heater and fan motor and an opposite side electrically connected to the timer motor and the first nonneutral power wire; and

a second switch operated by the timer motor and having a first side electrically connected to the heater and the fan and timer motor and an opposite side electrically connected to the second nonneutral power wire.

2. A hand dryer of claim 1 wherein the first switch comprises first switch contacts having a first state connecting the heater and fan motor to the first nonneutral power wire and a second state disconnecting the heater and fan motor from the first nonneutral power wire.

3. A hand dryer of claim 1 wherein the second switch comprises second switch contacts having a first state connecting the heater and fan and timer motor to the second nonneutral power wire and a second state disconnecting the heater and fan and timer motor from the second nonneutral power wire.

4. A hand dryer of claim 1 wherein the voltage potential is approximately 240 volts.

5. A hand dryer operable with first and second nonneutral power wires having a voltage potential therebetween, the hand dryer comprising:

a heater operatively connected to the voltage potential and having first and second power connections;

a fan motor operatively connected to the voltage potential and having first and second power connections;

a timer motor having a cam and operatively connected to the voltage potential, the timer motor having first and second power connections;

a first switch having a first contact in electrical communication with the first power connections of the heater and the fan motor and a second contact in electrical communication with the first power connection of the timer motor and the first nonneutral power wire, the first switch being mechanically operated by the timer motor and having a first state placing the first and second contacts of the first switch in electrical communication in response to operation of the hand dryer being initiated, and the first switch having a second state interrupting the electrical communication between the first and second contacts of the first switch in response to the cam on the timer motor actuating the first switch; and

a second switch having a first contact in electrical communication with the second power connections of the heater and the fan and timer motors and a second contact in electrical communication with the second nonneutral power wire, the second switch being mechanically operated by the timer motor and having a first state placing the first and second contacts of the second switch in electrical communication in response to operation of the hand dryer being initiated, and the second switch having a second state interrupting the electrical communication between the first and second contacts of the second switch in response to continued operation of the timer motor after the cam actuates the first switch,

the operation of the heater and timer and fan motors being started in response to the first and second switches being in the first state, the operation of the heater and fan motor being terminated in response to the first switch being in the second state and the second switch being in the first state, and the operation of the timer motor being terminated in response to the first and second switches being in the second state.

6. A hand dryer of claim 5 wherein the first and second contacts of the first switch is a pair of normally-closed contacts.

7. A hand dryer of claim 5 wherein the first and second contacts of the second switch is a pair of normally-closed contacts.

8. A hand dryer of claim 5 wherein the voltage potential is approximately 240 volts.

9. A hand dryer operable with first and second nonneutral power wires having a voltage potential therebetween, the hand dryer comprising:

a heater electrically connected to the nonneutral power wires and rated to operate at approximately the voltage potential;

a fan motor electrically connected to the nonneutral power wires and rated to operate at approximately the voltage potential;

a timer motor electrically connected to the nonneutral power wires and rated to operate at approximately the voltage potential;

a first switch mechanically operated by the timer motor and electrically connected between one of the nonneutral power wires and the heater and fan motor, the first switch having a first actuating arm switching a state of first electrical contacts at a consistent repeatable first time in response to operation of the timer motor; and

a second switch mechanically operated by the timer motor and electrically connected between one of the nonneutral power wires and the fan motor, the second switch having a second actuating arm switching a state of second electrical contacts at a consistent repeatable second time in response to operation of the timer motor.

10. A hand dryer of claim 9 wherein the second actuating arm is connected to the first actuating arm.

11. A hand dryer of claim 10 wherein the second actuating arm switches the state of the second electrical contacts at a consistent repeatable second time in response to motion of the first actuating arm.

12. A hand dryer of claim 11 wherein the first and second actuating arms are mechanically connected such that motion of the actuating arm causes the first switch to switch at the first time prior to the second switch switching at the second time.

13. A method of operating a hand dryer comprising:

providing a timer motor having a drive shaft with a cam lobe mounted thereon, the cam lobe being initially engaged with an actuating arm of first and second switches having contacts electrically disconnecting a heater, fan motor and timer motor from a power source;

disengaging the cam lobe from the actuating arm, thereby causing the first and second switches to electrically connect the heater, the fan motor and the timer motor to first and second nonneutral wires of the power source;

thereafter engaging and moving the actuating arm with the cam lobe to operate the first switch and electrically disconnect the heater and fan motor from the first nonneutral wire; and

thereafter continuing to move the actuating arm with the cam lobe to operate the second switch and electrically disconnect the timer motor, heater and fan motor from the second nonneutral wire.

14. A method of operating a hand dryer comprising:

providing a timer motor with a drive shaft having a cam lobe in contact with an actuating arm of first and second switches, the switches having contacts electrically disconnecting a heater, fan motor and the timer motor from a power source;

moving the cam lobe out of engagement with the actuating arm, thereby permitting the actuating arm to move to a position operating the switches and connecting the heater, the fan motor and the timer motor to two nonneutral wires of the power source;

moving the cam lobe into alignment with the cam lobe being rotated by the timer motor; and

rotating the cam lobe into contact with the actuating arm, thereby operating the first switch to disconnect the heater and the fan motor from the first nonneutral wire and thereafter operating the second switch to disconnect the heater, the fan motor and the timer motor from the second nonneutral wire.

15. A method of operating a hand dryer comprising:

providing a timer motor having a drive shaft with a cam slidably mounted thereon, the cam placing a cam lobe in contact with an actuating arm of first and second switches having contacts electrically disconnecting a heater, fan motor and the timer motor from a power source;

moving the cam in a first direction to disengage the cam lobe from the actuating arm, thereby permitting the actuating arm to move to a position causing the first and second switches to electrically connect the heater, fan motor and timer motor to first and second nonneutral wires of the power source;

moving the cam in an opposite direction to align the cam lobe with the actuating arm of the switches;

rotating the cam lobe with the timer motor into contact with the actuating arm;

moving the actuating arm with the cam lobe to operate the first switch and electrically disconnect the heater and fan motor from the first nonneutral wire; and

continuing to move the actuating arm with the cam lobe to operate the second switch and electrically disconnect the timer motor, heater and fan motor from the second nonneutral wire.