US3361996A

US3361996A - Sequential timing device for hand dryer and towel dispenser

Info

Publication number: US3361996A
Application number: US579240A
Authority: US
Inventors: Goldstein Arthur
Original assignee: Individual
Current assignee: Individual
Priority date: 1966-07-22
Filing date: 1966-09-14
Publication date: 1968-01-02
Anticipated expiration: 1985-01-02

Description

Jan. 2, 1968 A. GOLDSTEIN 3,361,996

SEQUENTIAL TIMING DEVICE FOR HAND DRYER AND TOWEL DISPENSER Fi led Sept. 14, 1966 2 Sheets-Sheet 1 INVENTOR Ann-we Comm ZM M ATTORNEY Jan. 2, 1968 I A. GDOLDSTEIN 3,36

SEQUENTIAL TIMING DEVICE FOR HAND DRYER AND TOWEL DISPENSER Filed Sept. 14, 1966 2 Sheets-Sheet z v e: i 12 Y A 3 I 19 r\ rE| I 16 0 f5 r\ rL MMQQQJ IN'VENTOR fig TH-u. GOA) TE TD/Md. M

ATTORNEY United States Patent 3,361,996 SEQUENTIAL TIMING DEVICE FOR HAND DRYER AND TOWEL DISPENSER Arthur Goldstein, 375 Milton Road, Cambridge, England Filed Sept. 14, 1966, Ser. No. 579,240 Claims priority, application Great Britain, July 22, 1966, 33,150/ 66 2 Claims. (Cl. 335-64) ABSTRACT OF THE DISCLOSURE returns the trip arm to a position deactuating the first switch.

This invention relates to sequential timing devices.

It is an object of the invention to provide a simple and inexpensive device which will control an electric switch so that the switch will be held open or closed for a predetermined time interval after each time it has been operated. The invention is primarily intended for the control of an electrical heater and blower in a hand drying device as described in the specification of my co-pending patent application No. 417,085 filed December 9, 1964, now patent 3,305,938. However, the invention is not restricted to such use as it could be used with advantage for many other purposes such as the control of traffic lights at pedestrian-operated crossings.

In the parent specification, there is described a sequential timing device comprising an actuating switch; an electric solenoid having a core which is displaceable from an inoperative position when the actuating switch is actuated, but which is free to return to the inoperative position when the solenoid is de-energized, a pair of suction cups one of which is carried by the core, the cups being so arranged that their faces are closed together when the core is displaced thereby to hold the core in the displaced position; an operating plunger which is carried by the core; and a controlled switch which is held open or closed as desired by the operating plunger when the core is in its inoperative position, but which is movable to the closed or open position when the core is displaced, air being permitted to enter between the cups after they have been closed whereby the cups will open after a predetermined time to permit the core to return to its inoperative position. The present invention provides a modification in which the actuating switch is actuated by movement of a trip arm and a second electric solenoid is arranged to be energised by the actuating switch simultaneously with the first solenoid thereby to return the trip arm to its inoperative position.

In the accompanying drawings:

FIGURE 1 is a sectional diagram illustrating and end of a hand drying device which is a preferred embodiment of the invention, and

FIGURE 2 is an electric circuit diagram.

In the illustrated embodiment of the invention an apparatus for drying the hands is provided with an electric timing device comprising an electric solenoid 1 (here inafter called the timer solenoid) mounted in a suitable bracket 2 on a housing 3 of the drying apparatus. The timer solenoid 1 has a core 4 which will be upwardly displaced when the solenoid is energised by operation of a main actuating switch 5 which is a micro switch. When the timer solenoid is not energised,'the core 4 will occupy a lower, inoperative position of rest.

The core 4 has an upper extension which carries the lower one (6) of a pair of suction cups. The upper one (7) of these cups is supported by screw 8 in the bracket 2 in an adjustable fixed position. The faces of the two cups 6, 7 are presented to each other and the cups are so positioned that when the timer solenoid core 4 is raised, by energising the solenoid, the faces of the cups are closed together. This will cause the cups to be held together so that the core is held in its raised position. An air inlet 9 is provided so that air can enter between the cups when closed whereby the suction between the cups will be broken after a predetermined time dependent on the setting of the adjustable upper cup. The suction cups can be made of a combination of rubber together with a non-sticky substance such as polyethylene or P.TlF.E.

The core 4 has a lower extension or operating plunger 10 projected beneath the solenoid. This operating plunger 10 is engageable with an arm 11 of a switch 12 to be controlled. The arm 11 and/or the operating plunger 10 is made of electrical insulating material. When the core is at its normal or inoperative position, the operating plunger is engaged with the switch arm to press it down and hold the switch in the open condition as shown in the drawing. When the actuating switch 5 is closed, the timer solenoid 1 is energised to raise the core 4 and operating plunger 10 thereby to enable the controlled switch 12 to close. The same movement also closes the cups 6, 7 together. After the predetermined time interval, the cups will open owing to the fact that air can enter through the air inlet 9 thereby to enable the core and operating plunger to fall so as to open the controlled switch.

If the actuating switch 5 is operated before the cups have opened, the device will be re-set so that the time interval desired will commence at the time of re-setting.

The actuating micro-switch 5 is actuated by movement of a pivotally mounted trip arm 13 of insulating material. This trip arm 13 is connected through a slip clutch 14- with an operating roller 15 extending through the casing 3. A stack of paper towels T inside the casing 3 rests on the roller 15 in such a way that the roller is rotated when the lowermost towel in the stack is withdrawn for the purpose of drying the hands. This will pivot the trip arm 13 connected to the roller 15 and will therefore actuate the micro-switch. Thus, the timer solenoid 1 will be energised to set in operation for a limited period, a blower motor 16 and an electric heater 17. An electric pre heater 18 remains permanently in operation.

The actuation of the actuating micro-switch 5 not only energises the time solenoid 1, but simultaneously energises a trip arm solenoid 19, connected to the switch in parallel with the timer solenoid 1, to displace a plunger 20 of that solenoid to return the trip arm 13 to its original position. Such return movement of the trip arm 13 against the rotation of the roller 15 is permitted by the slip clutch 14. The return movement of the trip arm 13 opens the mirco-switch 5, but the controlled switch 12 remains closed because of the action of the suction cups 6, 7. Return movement of the plunger 20 of the trip arm solenoid 19 is assisted by a spring 21.

The trip arm solenoid 19 provides a positive and effective means of returning the trip arm 13 to its normal or inoperative position regardless of the Weight of the stack of towels T. This is of considerable advantage as the weight of the towels obviously varies between a maximum when the casing 3 is fully charged with towels and a minimum when the casing is empty of towels. At maximum loading, the trip arm will not always return positively unless assisted by the solenoid 19.

What is claimed is:

1. A sequential timing device comprising an actuating switch; a trip arm moveable to actuate the actuating switch; a first electric solenoid energizable in response to said actuating switch and having a core, which is displaceable from an inoperative position when the actuation switch is operated, but which is free to return to the inoperative position when the solenoid is de-energised; a pair of suction cups one of which is carried by the core, the cups being so arranged that their faces are closed together when the core is displaced thereby to hold the core in its displaced position; an operating plunger which is carried by the core; a controlled switch which is held open or closed as desired by the operating plunger when the core is in its inoperative position, but which is movable to the closed or open position when the core is displaced, air being permitted to enter between the cups after they have been closed whereby the cups will open after a predetermined time to permit the core to return to its inoperative position and a second electric solenoid energizable in response to said actuating switch and being energised by operation of the actuating switch simultaneously with the first solenoid to act on the trip arm to return it to its original position.

2. In an electric hand drying appliance including a towel container and an electric heater and blower, a sequential timing device comprising an actuating switch; a trip arm movable to actuatethe actuating switch; a first electric solenoid energizable in response to said actuating switch and having a core which is displaceable from an inoperative position when the actuation switch is operated, but which is free to return to the inoperative position when the solenoid is tie-energised; a pair of suction cups one of which is carried by the core, the cups being so arranged that their faces are closed together when the core is displaced thereby to hold the core in its displaced position; an operating plunger which is carried by the core; a controlled switch responsive to the position of said plunger and which is held open or closed as desired by the operating plunger when the core is in its inoperative position, but which is movable to the closed or open position when the core is displaced, air being permitted to enter between the cups after they have been closed whereby the cups will open after a predetermined time to permit the core to return to its inoperative position, a second electric solenoid energizable in response to said actuating switch and which has a displaceable core and which is energised by operation of the actuating switch simultaneously with the first solenoid to displace the core, a plunger on the core and arranged to act on the trip arm and return it to its original position, an operating roller rotatable by withdrawal of a towel from the towel container, a slip clutch through which the operating roller is connected to the trip arm so that rotation of the roller will actuate the trip arm.

References Cited UNITED STATES PATENTS 2,898,428 8/1959 Holden 200-172 FOREIGN PATENTS 42,722 3/1938 Netherlands.

BERNARD A. GILH-EANY, Primary Examiner.

H. BROOME, Assistant Examiner.