US2690800A

US2690800A - Automatic reset timer

Info

Publication number: US2690800A
Application number: US249577A
Authority: US
Inventors: Donald H Ross
Original assignee: Automatic Temperature Control Co Inc
Current assignee: Automatic Temperature Control Co Inc
Priority date: 1951-10-03
Filing date: 1951-10-03
Publication date: 1954-10-05
Anticipated expiration: 1971-10-05

Description

Oct- 5, 1954 D. H. Ross 2,690,800

AUTOMATIC RESET TIMER Filed Oct. 3 1951 INVENTOR 5' .2 '54" .Donald H'. R055.

J`l 5'0 ATTORNEY.

Patented Oct. 5, 1954 UNITED STATES PATENT FFICE AUTOMATIC RESET TIMER Application October 3, 1951, Serial No. 249,577

3 Claims.

This invention relates to automatic reset timers of the mechanical type.

It is among the objects of the invention to improve the art of timers; to provide a timer of wide variance of time cycle; to provide a rotatable element with physically dstortable or movable means for controlling a timed circuit with erasing means for returning the distortable or movable means to neutral position; to provide a rotatable element with a plurality of normally inert or neutral elements incapable of contacting a circuit controller, with means for selectively displacing a selected element out of its neutral position into a positive contact actuating position; and to provide other objects and advantages as will become more apparent as the description proceeds.

In carrying out the'invention in an illustrative basic form, a rotatable element is driven at a known peripheral speed and is provided with portions or elements susceptible to displacement from a normal neutral position into a contactcontrolling active attitude.

In the accompanying drawings forming part of this description:

Fig. l represents a schematic vertical section through an illustrative form of the invention.

Fig. 2 represents a fragmentary front elevation of the same partially broken away,

Figs. 3 and 4 represent wiring diagrams for the operation of the device.

Figs. 5 to 13 represent fragmentary details of the device and modications thereof.

In the preferred but illustrative form of the invention a synchronous motor iii through gears I E drives a shaft I2 on which is mounted a timing disc i3. In one illustrative form of disc I3, the peripheral edge is turned in a stiiening ange It and in a peripheral annular area I5 adjacent to the edge, a plurality of arched resilient anchored fingers i6 are formed by substantially radial slots Il on each side of each linger, and by distorting each metal linger it between its ends into the arched resilient deformation out of the plane of the disc I3. The fingers and slots are as reasonably narrow as possible in order to increase the accuracy of the timer by sub-dividing the nger area I5 in its greatest number of components. It will be understood that the normal attitude of the arch of the fingers is with the arches iall lying in a peripheral path on one face of the disc lying in a plane parallel thereto in what may be termed the neutral or passive attitude. It will be understood, however, that in response to suitable irnpact or thrust in a line parallel to the axis of the shaft in the substantial center of a finger I6, any

nger so impinged can ex resiliently through the space between slots Il defining the iinger to spring outwardly of the disc in the opposite direction as indicated at 20.

It will be understood that with the circuits properly arranged and with a common starting point at all times, say, at the center of the top of the disc, at the zero or datum point, the finger of the operator can depress or actuate a suitable element which will simultaneously force the top finger of the disc into reversed active position indicated at 2t, will close or open the timing circuit to initiate the timing cycle and, if desired, will also close the circuit to the synchronous motor Iii to start the disc rotating in a timing cycle. It will be understood that repeat Kaction without time loss can also be accomplished, by causing the active element signal, closing (or opening) of

switch

25, 26, to simultaneously energize the hammer 311i to initiate a repeat cycle. This can be repeated continuously without the delay necessary in re-setting conventional devices. For this purpose, as well as generally, it is preferred to have the disc continuously rotated at a known timed rate so that the motor control is usually separate.

In order to determine and control a variable time cycle, a knob 2l carrying a pointer 22 is mounted in front of the disc, oscillatble on the axis of the shaft I2, by a concentric shaft It, and positionable angularly of the axis of the shaft I2 and disc I3 through approximately 330. Shaft I8 carries an insulating block 2li mounting two contact fingers respectively 25 and 25, usually biased apart, and nger 2e carries a cam extension 2l extending toward the area it in position to be engaged and moved by the distorted nger 20 in the cyclic progression of the disc i3. It will be understood, of course, that, if desired, the

contact lingers

25 and 25 can be biased together to be opened or separated when the advancing in-bent finger 2t engages the cam end 2l of the nger 2S. In the usual course, however, it is preferred that the contact of the cam 2l' with the advancing linger 2li will close the contacts. It will be understood that these fingers are in a circuit containing a load relay as shown in Fig. 3, actuated at the end of the timed interval- The beginning of the timed interval being established by the closing of the switch of pulse timing circuit shown in Fig. 4.

This circuit is from a source of d. c. through the high resistance coil t@ and across condenser 3|. With the switch 32 open, the condenser charges. When the switch 32 is closed momentarily, the condenser discharges through the solenoid coil 33 in a pulse which moves the hammer element 34 smartly against the finger l5 to which it is juxtaposed. This impact snaps the impacted finger le from its peripheral registration with the remainder of the series thereof in the area l5, into the reversed active position indicated at 2S, and starts the timing interval. After the timed motor running has continued to a point proper to bring the active finger 2G into contact with the cain 2l of the finger 26, the timed interval is concluded. As the timing interval usually does not stop the running of the motor upon its conclusion, it is necessary to erase the signal by returning the bent active finger into the inactive series thereof. This is easily accomplished by providing radially spaced anvil rollers 35 and S5 bearing slightly against one surface of the disc 3D straddling the finger area i5, and an erasing roller 3l spaced between them on the opposite side of the disc in position to be engaged by the advancing ringer 2G to snap saine back into its inactive position. If desired, the anvil rollers may be disposed in coinpleinental pairs on both sides of the disc. This furnishes a backingup anvil effect to hold the disc against the distortion when the hammer blow is struck against the nger I6.

It will be seen that the disc i3 can be a stamping and can be produced very cheaply and efficiently, and that although the start of the timing interval is located by the fixed position of the hammer 3d, the end of the timed cycle is variable, depending upon the angular positioning of the

contact fingers

25 and 25 determined by the angular setting of the knob 2l and pointer 22. The simplicity and efficiency of the invention will be appreciated.

1t will be understood, however, that within the broad purview of the invention, other mechanical devices may be used, movable between passive and active position on a support. Thus, in Figs. 6 and 7 the disc i3 is provided with a peripheral series of apertures 4G within which are mounted notched plungers il guided for axial motion in the apertures, and having spring elements 4.2 disposed to engage in one or the other of the notches or grooves i3 and iid of the plunger. It will be seen that the hammer impact against the end of a given plunger in the inactive position thereof shown in Fig. 6, snaps the plunger inwardly to the active position thereof shown in Fig. '7. The roller or other erasing element 31 forces it outwardly again in the cyclic rotation of the disc i3.

In the form of the invention shown in Figs. 8 and 9, the disc I3 mounts a series of pivoted shutters 5U, the axes of which are radial of the rotational axis of the disc I3 and in the inactive or passive position of the parts are in general alignment in the periphery oi the disc. They may be held in this position by spring elements or friction as seems most expedient. The conversion of a given shutter from the passive position to the active circuit-controlling position is by having the hammer impact on one side of the shutter beside its axis, to twist the shutter on its axis to the active position shown by the right hand shutter in Figs. 8 and 9. The erasure of the active signal is by returning the given shutter to its aligned position.

Fig. 10 is a fragmentary plan partially in section illustrating the relationship of two of the rollers to the ngers of the disc of Fig. 1.

A further modified form is shown in Figs. l1, 12, and 13, in which the disc 5e has spring ngers 5 I, the normal resilience of which urges them into coextension with the planar portion of the disc 5B. The disc 5U' is juxtaposed to a magnetized disc 52, one face of which, adjacent the fingers 5I, has one given polarity, illustratively north. The other face of the disc 52 constitutes the south pole, but this is unimportant. In the rotation of the disc 50 with disc 52 the rollers, as shown in the other gures and for clarity are omitted in Figs. l1 to 13 inclusive, force the spring fingers out of their normal planar relation and into contact with the north face of the disc 52, in which position they are maintained as shown in Fig. ll by the magnetic attraction between the spring fingers 5i and the polarized disc e2. The relatively narrow permanent magnet hammer 36 has a limited stroke, preferably avoiding actual contact with the fingers 5|, and the advancing end thereof is polarized with the same polarity as the iinger-engaging and latcliing face of the disc 52. In the illustrative example, the advancing end of the hammer 3d is polarized north. Actuation of the switch 32 moves the hammer til toward a given finger 5l, to such adjacency thereto as to neutralize the magnetic limi retaining the said nnger 5i against the disc permitting the particular selected nger with which the hainmer is aligned to snap into its normal alie'ned relation with the disc, as shown in Fig'. l2. It is preferred that both the hammer end and the respective fingers 5l be relatively narrow and that the space between fingers be minimal, to the end that usually but a single finger is unlatched to respond to its bias toward alignment with the disc. In the event that the hammer moves so close to two of the fingers as to simultaneously release both from latched engagement with the disc, it is the forward finger of the two which becomes the actuated nger 2S. This possibility of releasing either one or a plurality of ngers introduces a potential error, by the width of the space between fingers plus the width of one finger. In a rapid rotation and small time interval this is inconsequential, whereas in a slow moving device of long time cycle, it becomes material and undesirable. It is to be noted, however, that when, if ever, more than one finger is unlatched simultaneously, it is the advancing finger which controls some such switch arrangement as is shown in Fig. l, and the others have no effect thereon. At the conclusion of its cycle the actuated finger, or lead finger of two or more thereof, actuate a switch, as 2.3, 28 and 2i' of Fig. l, to end the timed cycle. When the single finger is released to form the actuated finger, the immediate reset delay following conclusion of the timed cycle is always at least for the width of the space between fingers, but in general follows the immediate reset available with the other forms of the invention.

At the conclusion of the timed cycle suitable rollers, as shown in the other figures, again engage the extended or actuated nger 28 and push it back into magnetically latched engagement with the disc 52, as will be clear.

Fig. 13 is a slightly enlarged fragmentary view showing the successive positions of the hammer and the given finger 5| in the respective movements of both in respective full and dotted lines.

The foregoing are illustrative of some of the ramifications and modifications available with the invention, and many others will occur to those skilled in the art, and all such are to be construed as within the scope and spirit of this invention.

Having thus described my invention, I claim:

1. In apparatus of the class described, a rotatable disc having an axis of rotation, means for rotating the disc on its axis at a time-controlled rate, said disc comprising an inner portion mounting an integral outer portion comprising a multiplicity of individual iingers generally radial of said axis in a peripherally continuous series with contiguous fingers in spaced relation, each of said fingers being bendable between a rst and a second attitude relative to the inner portion of the disc, manually adjustable means mounted for oscillation on an axis coextensive vwith the axis of said dise, circuit-controlling means mounted on said adjustable means adjacent to said peripherally continuous row of iingers incapable of actuation by any of said fingers in its rst position but intersecting the rotative path of any ringer in its said second position for actuation by such finger to control a circuit independent of said disc, means at a fixed point adjacent to the outer portion of said disc for moving the instantaneously juxtaposed finger of the series from its rst to its second position to initiate a timing cycle completed When the thus actuated iinger abuts the angularly positioned circuit controller, and means between the circuit controller and said xed point in the direction of rotation of the disc for moving said moved nger from its second position to its first position.

2. Apparatus as -recited in claim 1, in which the respective iingers are anchored to the disc at both ends and are distorted respective to the remainder of the disc so as to move between a generally bowed attitude at the rst position to an oppositely bowed attitude at the second position.

3. Apparatus as recited in claim 1 in which the disc and iingers are of resilient magnetic material and in which the fingers have an inherent resilient urge to move into their respective second positions, a magnet is provided juxtaposed to the respective fingers for magnetically holding them in their respective rst positions against said urge, said means at said fixed point comprising a permanent magnet of the same polarity as said first mentioned magnet and arranged upon movement toward said disc to neutralize the magnetic pull of said first mentioned magnet to permit the selected nger to respond to its said urge and to move into its said second position.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,436,422 Wiles Nov. 21, 1922 1,548,043 Kennedy Aug. 4, 1925 1,801,129 Warren Apr. 14, 1931 1,898,893 Reichold Feb. 21, 1933 2,077,684 Gensburg Apr. 20, 1937 2,272,545 Chalupowski Feb. 10, 1942 2,380,969 King Aug. 7, 1945 2,536,133 Klammer et al Jan. 2, 1951 2,627,919 Lindahl Feb. 10, 1953