US3214985A

US3214985A - Timer

Info

Publication number: US3214985A
Application number: US215892A
Authority: US
Inventors: August J Danek; Allan E Visin; Thomas M Clune
Original assignee: Controls Company of America
Current assignee: Controls Company of America
Priority date: 1962-08-09
Filing date: 1962-08-09
Publication date: 1965-11-02
Anticipated expiration: 1982-11-02

Description

Nov. 2, 1965 A. J. DANEK ETAL 3,214,985

TIMER Filed Aug. 9, 1962 2 Sheets-Sheet 1 Fla.3

INVENTORS {E Queusw; J Dam-1 LLAN L. l m 58 THoMas M.Cu.m

- 01 BY M I 22 i 24, 'IIIIIIIIIIIIIIIIIIIIlI-lIlu IIIIIIIIIIIIIIIJ ATYORNEY NOV. 1965 A. J. DANEK ETAL 3,214,985

, TIMER Filed Aug. 9, 1962 2 Sheets-Sheet 2 INVENTORS AUGUST J. DANEK ALLAN E.\)|5IN United States Patent 3,214,985 TIMER August I. Danek and Allan E. Visin, Crystal Lake, and

Thomas M. Clune, Park Ridge, Ill., assignors to Controls Company of America, Melrose Park, Ill., a corporation of Delaware Filed Aug. 9, 1962, Ser. No. 215,892 6 Claims. (Cl. 7454) This invention relates to a simple timer of the type generally employed to give a constantly repeating program. Timers of this type are frequently used in appliances and the like and the present timer is designed to control the defrost action of a refrigeration system, usually a hot gas defrost system requiring but a short period of time in which to effect the defrost action.

By reason of the environment in which the timer is to be used and the class of goods upon which the timer is to be used such a timer must be capable of manufacture at low cost. The appliance manufacturer is not always certain vjust what frequency of defrosting action will be required since this is dependent upon the ambient conditions surrounding the appliance. Prior to the present invention the manufacturer utilized a cam actuated timer mechanism which provided a given frequency of defrost action dependent upon the configuration of the cam. If greater or lesser frequency was required by the ultimate installation then the manufacturer replaced the cam in the timer to give the desired result. The manufacturer generally did not know of the failure of the original cam to meet the ambient conditions until receiving a customer complaint which, while able to be remedied, is not good customer relations. Furthermore, the remedy required a visit of a service man and reduced the earnings of the manufacturer.

The'pn'ncipal object of this invention is to provide a simple timer which can be manufactured at very low cost and which can be adjusted in the field by the user to change the frequency of actuation.

Other objects and advantages will be pointed out in, or be apparent from the specification and claims, as will obvious modifications of the single embodiment shown in .thedrawings, in which:

FIG. 1 is a front elevation of the timer;

FIG. 2 is a bottom view of the timer;

FIG. 3 is an enlarged fragmentary section taken as indicated by line 3-3 on FIG. 1;

FIGS. 4 and 5 are piece part drawings of the two discs which comprise the stop and which are relative-1y movable to determine the frequency of switch actuation;

FIG; 6 shows the two discs comprising the stop positioned to give one switch actuation and one revolution of the pulsing cam which appears at the right in FIG. 1;

FIG. 7 is comparable to FIG. 6 but gives two actuations per cycle;

FIG. 8 shows the parts positioned to give three pulses per cycle; and

FIG. 9 shows the parts positioned to give six pulses per cycle.

Shaft 10 projecting from housing 12 is, in the illustrated embodiment, designed to rotate one revolution in 15 minutes and is driven by an electric motor and reduction gearing which are not shown. The shaft carries a pulse cam 14 and a pinion gear 16 which drives idler 18 to "Ice rotate gear 20 mounted on hub 22 rotatably mounted on stub-shaft 24. The gear train from shaft 10 to hub 22 provides a six to one reduction so that the hub rotates one complete revolution every 90 minutes. A stop 26 also rotates with the hub 22 and this stop cooperates with pulse cam 14 to determine the frequency of actuation of the switch contained in switch housing 28 mounted on the front of the mounting plate 12. The switch is actuated by plunger 30 through the medium of lever 32 pivoted at 34 and having its free end formed to serve as a cam follower riding on the periphery of pulse cam 14. In the position shown in FIG. 1 slight continued rotation of pulse cam 14 will allow the follower to drop into notch 36. The usual switch construction biases the plunger 30 outwardly but for illustration purposes an additional spring 38 is shown biasing lever 32 so that it is clear that the follower end 40 will follow the peripheral configuration of the pulse cam 14. If the follower drops into the notch 36 it will be apparent that continued rotation of the cam 14 will occasion the inclined surface 42 acting against the follower to lift the follower back to its original position and trip the switch to its normal position.

The switch lever 32 is provided with a depending arm 44 having its lower end turned back to overlie the peripheral surface of the cycle cam 26 It will be apparent that as lever 32 drops from the position shown in FIG. 1 it can drop all the way down to the bottom of the notch only in the event there is a notch on the stop 26 to receive the inturned end 46 of the arm 44. In the position shown in FIG. 1 there is such a notch present on the stop 26. Since the rotational speed of stop 26 is one-sixth that of the pulse cam 14 the pulse cam 14 will cause the arm 44 to be withdrawn from the notch in the stop 26 before the vertical face of the notch abuts the arm. In the p0s-i tion of the parts shown in FIG. 1 it will be apparent that there is only one notch provided in stop 26 and, hence, the switch 28 can be actuated only once in six revolutions of the pulse cam 14. On the other five revolutions the continuous peripheral surface of the stop 26 will prevent the lever 40 from following the configuration of the pulse cam.

Stop 26 is made up of two

discs

48 and 50. The rear disc 48 is fixed on hub 22 to be driven through the gear train so as to be in synchronism with the pulse cam. The front disc 50 is fixed to knob 52 which is slidably mounted on stub shaft 24 and biased by spring 54 compressed between ring 56 and the inside shoulder of the knob to urge the knob and the disc 50 to the position shown in full lines in FIG. 3. The knob may be manually withdrawn against the bias of spring 54 so as to move the disc 50 to the position shown in dotted lines in which position the pins 58 carried by the front disc are withdrawn from the cooperating holes in the rear disc to permit relative rotation of the front disc with respect to the rear disc.

The two discs are shown in FIGS. 4 and 5. FIGS. 6 through 9 show the different relative rotational positions of the discs. It will be noted that in FIG. 6 (as in FIG. 1) the front disc is positioned with respect to the rear disc so as to place the indicating arrow 60 (carried by the front disc) adjacent the numeral 1 carried by the rear disc. This indicates that one notch is exposed or that the switch will be actuated once during each complete cycle, that is, once in minutes. In FIG. 7 the arrow indicates the numeral 2 and here two notches are exposed on the periphery of stop 26 and it will be noted that these notches are diametrically opposed so as to provide equal intervals (45 minutes) between actuation of the switch. In FIG. 8 three notches, again equaly spaced, are provided on the periphery of the cam so as to provide for switch actuation every 30 minutes while in FIG. 9 six notches are provided to give a switch actuation every minutes.

It will be noted the rear disc shown in FIG. 5 has six equally spaced notches while the front disc is provided with notches which are unequally spaced with respect to each other and the notches in the front disk and which also have different peripheral lengths so as to permit obtaining the different combinations of notch overlap neces sary to obtain the variety of cycling afforded by this invention. In this regard the notches in cam 14 and

disks

48 and 50 can be considered as active portions with respect to the switch lever 32 and its operating arm 44 since these members move and switch 28 is activated only when the switch lever and the operator arm are aligned with the notches, whereas, the outer peripheral portions between the respective notches can be regarded as inactive portions since the switch lever and operating arm are held in an inactive position, with respect to switch 28, when they are either jointly or singly engaged with their respective cam and disk outer peripheries.

It will be appreciated that when the parts are in the position shown in FIG. 3 the pins 58 transfer the drive from disc 48 to disc 50 and additionally serve to positively retain the disc in position. As can be seen in FIG. 5 various spaced holes are provided to receive the pins and give the requisite positive location of the two discs with respect to each other.

Although but one embodiment of the present invention has been illustrated and described, it will be apparent to those skilled in the art that various changes and modifications may be made therein without departing from the spirit of the invention or from the scope of the appended claims.

What we claim is:

1. A timer comprising, in combination,

control means,

rotatable cam means having at least one notch in the periphery thereof,

rotatable stop means comprising a first circular disk having aplurality of notches arranged in predetermined spaced relationship on its periphery and a second circular disk adjacent said first disk and having a plurality of notches arranged in predetermined spaced relationship on its periphery, the spacing between and the circumferential extension of the notches in said second circular disk being different from the spacing between and the circumferential extension of the notches in said first circular disk,

actuating means for said control means including a follower biased toward engagement with said cam means and the first and second disksof said stop means,

means connecting said cam and stop means for movement at a predetermined speed ratio and with said first disk arranged relative to said cam means to position one of the notches of said first disk in underlying relation with said follower when the notch on said cam means underlies said follower.

and means connecting said first and second disks for relative movement therebetween to move the notches of said second disk into and out of registry with the notches in said first disk and vary the number of notches of said first disk which are open to said follower for release thereof.

2. A timer according to claim 1 wherein the numberof notches on said first disk are any whole integer of the speed ratio multiplied by the number of notches in the periphery of said cam means.

3. A timer according to claim 1 wherein the notches in said first disk are equally spaced.

4. A timer according to claim 2 wherein said disks are coaxially arranged and supported for relative axial movement and for joint and relative rotational movement, and including means biasing said disks into engagement with each other and one of said disks including at least one axially extending pin and the other disk including a plurality of pin receiving openings relatively spaced in accordance with the relative spacing of the notches on said first and second disks so that engagement of said pin in one of said openings arranges said first and second disks relative to each other to expose a desired number of notches on said first disk to said follower.

5. A timer comprising, in combination,

control means,

movable cam means having an operating periphery and at least one notch in said periphery,

movable stop means comprising a first member having an operating periphery provided with a plurality of notches arranged in predetermined spaced relationship and a second member adjacent said first member having an operating periphery provided with a plurality of spaced notches forming alternate blocking portions and operating notch portions in the periphery of said second member, the spacing between the notches in the periphery of said second member being different from the spacing between the notches in the periphery of said first member,

actuating means for said control means biased toward engagement with the operating peripheries of said cam means and first and second members,

means connecting said cam and stop means for movement at a predetermined speed ratio and with said first member arranged relative to said cam means to position one of the notches of said first member in underlying relation with said actuating means when the notch on said cam means underlies said actuating means,

and means connecting said first and second members for adjustable relative movement therebetween to move the blocking and notch portions of said second member into and out of registry with the notches in said first member to vary the number of notches of said first disk which are open to said actuating means for release thereof.

6. A timer comprising, in combination,

control means,

movable cam means,

movable stop means comprising first and second members, actuating means for said control means biased toward engagement with said cam means and said first and second members,

said movable cam means having active and inactive portions with respect to said actuating means,

said first member including active and inactive portions with respect to said actuating means and said second member supported for adjustable movement relative to said first member, said second member including a plurality of blocking portions, said blocking portions being relatively spaced on said second member with the spacing therebetween being different from the relative spacing between the active portions of said first member so that said blocking portions are arranged to be selectively aligned with the active portions of said first member to vary the number of active portions of said first member which are operatively exposed to said actuating means,

and means connecting said cam means and stop means for movementv at a predetermined speed ratio with said first member arranged relative to said cam means to position an active portion thereof in underlying relation with said actuating means when the active portion of said cam means underlies said actuating means thereby aligning said actuating means with the active portions of both said cam means and said first member for operation of said actuating means to actuate said control means, said 5 blocking portions operative, when aligned with said 232,926 active portions, to hold said actuating means against 343,857 movement as a result of said blocking portions over- 2,230,527 lying the active portions of said first member. 2,301,556 5 2,405,818 References Cited by the Examiner 2 596 330 UNITED STATES PATENTS 105,597 7/70 Rank 192---62 Berkholz 19262 Richards H 7453 Crawford et a1. 74526 Maris 7453 Denniston et a1. 74-526 Everard 74526 X BROUGHTON G. DURHAM, Primary Examiner.

Claims

1. A TIMER COMPRISING, IN COMBINATION, CONTROL MEANS, ROTATABLE CAM MEANS HAVING AT LEAST ONE NOTCH IN THE PERIPHERY THEREOF, ROTATABLE STOP MEANS COMPRISING A FIRST CIRCULAR DISK HAVING A PLURALITY OF NOTCHES ARRANGED IN PREDETERMINED SPACED RELATIONSHIP ON ITS PERIPHERY AND A SECOND CIRCULAR DISK ADJACENT SAID FIRST DISK AND HAVING A PLURALITY OF NOTCHES ARRANGED IN PREDETERMINED SPACED RELATIONSHIP ON ITS PERIPHERY, THE SPACING BETWEEN AND THE CIRCUMFERENTIAL EXTENSION OF THE NOTCHES IN SAID SECOND CIRCULAR DISK BEING DIFFERENT FROM THE SPACING BETWEEN AND THE CIRCUMFERENTIAL EXTENSION OF THE NOTCHES IN SAID FIRST CIRCULAR DISK, ACTUATING MEANS FOR SAID CONTROL MEANS INCLUDING A FOLLOWER BIASED TOWARD ENGAGEMENT WITH SAID CAM MEANS AND THE FIRST AND SECOND DISKS OF SAID STOP MEANS, MEANS CONNECTING SAID CAM AND STOP MEANS FOR MOVEMENT AT A PREDETERMINED SPEED RATIO AND WITH SAID FIRST DISK ARRANGED RELATIVE TO SAID CAM MEANS TO POSITION ONE OF THE NOTCHES OF SAID FIRST DISK IN UNDERLYING RELATION WITH SAID FOLLOWER WHEN THE NOTCH ON SAID CAM MEANS UNDERLIES SAID FOLLOWER. AND MEANS CONNECTING SAID FIRST AND SECOND DISKS FOR RELATIVE MOVEMENT THEREBETWEEN TO MOVE THE NOTCHES OF SAID SECOND DISK INTO AND OUT OF REGISTRY WITH THE NOTCHES IN SAID FIRST DISK AND VARY THE NUMBER OF NOTCHES OF SAID FIRST DISK WHICH ARE OPEN TO SAID FOLLOWER FOR RELEASE THEREOF.