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Publication numberUS3501909 A
Publication typeGrant
Publication dateMar 24, 1970
Filing dateJan 15, 1968
Priority dateJan 15, 1968
Publication numberUS 3501909 A, US 3501909A, US-A-3501909, US3501909 A, US3501909A
InventorsConradt Richard J
Original AssigneeConradt Richard J
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Interval timer
US 3501909 A
Abstract  available in
Previous page
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Claims  available in
Description  (OCR text may contain errors)

R. J; CONRADT INTERVAL TIMER March 24, 1970 2 Sheets-Sheet 1 Filed Jan. 15, 1968 I INVENTOR RICHARD J. CONRADT 7 W AffTORNEYS March 24, 1970 R. J-. C ONRADT INTERVAL TIMER 2 Sheets-Sheet 2 Filed Jan. 15, 1968 FIG. 7

FIG. 8

FIG. 9


3,501,909 INTERVAL TIMER Richard J. Conradt, 774 Meigs St., Rochester, N.Y. 14620 Filed Jan. 15, 1968, Ser. No. 697,689 Int. Cl. G04f 3/02 US. Cl. 5822.9 Claims ABSTRACT OF THE DISCLOSURE This timer may be set to operate at less than the maximum operating period of the mechanism which actuates it. For use with a citizen band radio, for instance, it will be set to time five minute intervals. A translucent dial having two sets of indicia around its reading face on red and green segments, respectively, covers the front of the instrument. To set the timer, a stop is rotatably adjusted angularly away from zero position, in which one of the segments is uppermost, in correspondence with the interval to be timed. The timer drive shaft is then rotated angularly to this stop position by a knob which carries a spring-pressed detent that rotates the dial with the knob and a block on the dial winds a torsion spring. When the knob reaches the stop this spring rotates the dial slightly beyond the stop to bring the other segment of the dial uppermost.

This invention relates to timers, and more particularly to a consecutive interval timer for indicating the passage of a plurality of predetermined time periods. In a more specific aspect, this invention relates to a timer, which is particularly adapted for use with citizen band radios to provide both visual and audible indications of the time periods in which the radio may be used for transmitting and receiving, respectively.

It is conventional to employ an interval timer, which can be set manually to control the interval of time during which an associated machine (for example, a washing machine, a dryer etc.) will operate. Such a timer, for example, may be adjusted by a manually-operable knob, which can be rotated up to nearly 360 to set the desired timing interval before the device times out. In some cases, upon expiration of the set time, the timer will actuate an alarm, as in the case of a timer or an electric cooking stove.

In many instances it is desirable to use an interval timer which can be used to measure identical intervals of time consecutively. In the case of citizen band radios, for example, which by reason of FCC (Federal Communications Commission) regulations cannot transmit for more than five minutes at a time, and which must stand by for at least five minutes between each transmitting period, a timer capable of timing five minute intervals consecutively would be particularly useful. However, interval timers, which are designed specifically for this purpose, are not commercially available. As a consequence it has been the practice to employ, for example, a fifteen or sixty minute timer and to rotate the timer shaft through only a part of a revolution, when it is desired to measure an interval less than the maximum that can be measured by the timer. The disadvantage of this practice, as employed with known timers, however, is that extreme care must be taken in setting the timed to a value less than its maximum, because there is no automatic indication of when the timer is properly so set. Moreover, While such prior timers usually incorporate a switching mechanism ice for either starting or stopping an operation, or for actuating a warning device, when the respective timer has timed out, or returned to zero, such prior timers have not included adequate means for visually indicating the status of the timer at any particular instant.

One object of this invention is to provide a timing device useful in measuring, audibly and visibly, equal or differe'nt lengths of time in sequence or otherwise.

Another object of this invention is to provide an improved timer, which can readily be set precisely to measure a desired time interval.

Another object of this invention is to provide an improved interval timer, which can be adjusted easily to alter the time interval measurable thereby.

A further object of this invention is to provide novel means for indicating time lapse on an interval timer of the type described.

A still further object of this invention is to provide means for converting a timer capable of operating for a given period of time so that it operates at less than that interval.

Still another object of this invention is to provide a consecutive interval timer for measuring and indicating successive time intervals and color coded for easier identification of the cycle in which it is operating at any one time. A more specific object of this invention is to provide a fiveminute interval timer, which is particularly adaptable for timing the operations of a citizen band radio.

Other objetcs of the invention will be apparent hereinafter form the specification and from the recital of the appended claims, particularly when read in conjunction with accompanying drawings.

In the drawings:

FIG. 1 is a front elevational view of an interval timer made in accordance with one embodiment of this invention;

FIG. 2 is a side elevational view of this timer with parts thereof broken away and shown in section;

FIG. 3 is a perspective view of this timer with its actuating knob and graduated dial removed;

FIG. 4 is a front elevation view illustrating in detail the adjustment assembly for the timer;

FIG. 5 is a side elevational view of the assembly shown in FIG. 4;

FIG. 6 is a sectional view taken along the 66 in FIG. 2 looking in the direction of the arrows, with parts of the adjustment assembly removed;

FIG. 7 is a fragmentary sectional view taken along the line 77 in FIG. 6 looking in the direction of the arrows;

FIG. 8 is an enlarged, fregmentary sectional view taken along the line -88 in FIG; 7 looking in the direction of the arrows; and

FIG. 9 is a view similar to FIG. 6, but illustrating the dial and its block rotated from the position shown in FIG. 6.

Referring now to the drawings by numerals of reference, 2O denotes an interval timer comprising a generally cup-shaped shell 21 containing the cylindrical housing 22 of a conventional timer mechanism, which has not been illustrated in detail herein. The shell 21 is adapted to be supported by a right angular mounting bracket 24, one leg 23 of which extends across the open end of the shell. Around its perimeter leg 23 has a plurality of integral lugs 25, which are secured against the inside surface of shell 21 by screws 26. The actuating shaft 28 (FIGS. 3, 6 and 7) of the timer mechanism projects out of housing 22 and through a central opening in the bracket leg 23.

Secured to the outer face of leg 23 coaxially of shaft 28 is a thin, dielectric disc 30 (FIGS. 2 and 3), which has fastened to its outer face a pair of arcuate, metal conductor strips 31 and 32, that are radially spaced coaxially from one another and from shaft 28. At one end thereof, their lower ends as illustrated in FIG. 3, these strips 31 and 32 are connected to a pair of wire leads 34. These leads extend through an opening in a stationary wire guide 35 on disc 30, through the space between shell 21 and the housing 22, and through a grommet 36 in the rear end of shell 21, to a source of electric power at the exterior thereof.

Secured at one end thereof to the insulating disc 30 between the lower ends of conductors 31 and 32 is a further, dielectric insulator 37 (FIG. 3). The opposite end of insulator 37, which extends radially outwardly relative to shaft 28, and over the outermost conductor 31, has on its outer end an offset tab 38, that projects outwardly beyond the outer edge of the bracket leg 23. Intermediate its ends insulator 37 has a knife edge 39, which extends transversely across the outermost conductor 31 for a purpose described below.

Mounted at one end for pivotal adjustment about the shaft 28 is a time range setting arm 41 (FIG. 3), which has at its outer end an offset portion 42 that projects radially beyond disc 30. Intermediate its ends arm 41 has a right angular stop lug 43, which projects away from the disc 30. Also rotatably adjustable on the shaft 28, and overlying the arm 41 is a dial setting arm 45, which also has a laterally offset outer end 46 that projects radially beyond the periphery of disc 30. Arm 45 carries a torsion spring 47 (FIG. 4), one end of which is clamped beneath a rolled edge 48 of this arm. The opposite end 49 of spring 47 is axially spaced from arm 45 and extends radially inwardly, and tangentially of shaft 28.

Arms 41 and 45 are adjustably secured together by'a screw 51, which extends through registering slots 52 in the arms 41 and 45, and which threads through the disc 30 and bracket leg 23 into the housing 22 of the timer mechanism. Three washers 53, the outer one of which may be for example, a rippled shaped spring washer, are interposed between, respectively, the arms 41 and 45, arm 41 and disc 30, and arm 45 and the head of screw 51, so that either arm 41 or arm 45 may be adjusted about the shaft 28 without disturbing the other.

The outer end of shaft 28 is slotted in conventional manner to provide a pair of resilient prongs or furcations 28 (FIG. 3), the outer faces of which are flatted off. Secured at one end to one of the prongs 28' for rotation by the shaft 28 is a pointer 55, the radially outer end of which tapers to a point adjacent the periphery of disc 30. Removably mounted in a socket in the outer end of pointer 55 is a bulb 56, which is connected in circuit with a pair of spaced, metal brushes or conductors 57 (FIG. 3), which projects from one side of the pointer 55. The outer end of one of these brushes 57 is constantly engaged with the radially innermost conductor strip 31 on disc 30 regardless of the position of the pointer 55, but the other brush 57 is engaged at its outer end with the insulator 37 when the timer is in its zero position as illustrated in FIG. 3, and is in contact with the other conductor 32, when the timer is operating. At the pointed end of pointer 55, the socket containing bulb 56 is covered by a white, translucent material, which illuminates the pointer when the bulb 56 is energized.

Rotatably mounted on the shaft 28 over the pointer 55, and overlying the peripheral edge of the disc 30 coaxially thereof is an inverted, generally bowl-shaped dial 60 (FIGS. 1, 2 and 6 to 9). Dial 60 is made of a translucent plastic material, or the like, and adjacent its periphery is provided with a conical surface portion 61 upon which is inscribed, two diametrically-opposed sets of indicia, each of which, in the case illustrated, includes the numbers zero to five, inclusive. One-half of the dial 60, for example, the upper half thereof as illustrated in FIG. 1, is preferably tinted red, while the other half (the lower half in FIG. 1) is preferably tinted to a contrasting color as, for instance, green. Normally, when the associated citizen band radio is not transmitting, the red half of the dial 60 will be uppermost, as illustrated in FIG. 1, and the green portion of the dial will be lowermost. Dial 60 is secured against axial movement on the shaft 28 by a conventional knob 62, which is shaped as a pointer having an indicating pointer end 63, and which has at one side thereof a centrally disposed blind bore that is pressfitted over the resilient furcations 28' of the shaft.

Integral with the inside face of the dial 60 is a rectangular block or land 64 (FIGS. 6, 7 and 9), which is engaged by the end 49 of torsion spring 47. Mounted to reciprocate parallel to the shaft 28 in a recess 66 in the outer end of knob 62 is a detent 67 (FIGS. 7 and 8), which has a cam surface 75 at its inner end, and a reduced diameter shank that is urged into engagement with dial 60 by a spring 68, which is mounted in recess 66 between the bottom of the recess and the detent. A washer 69, which is press-fit in a counterbore in the open end of recess 66, surrounds the shank of the detent 67 limiting movement thereof out of the recess 66.

At diametrically opposite sides of shaft 28 dial 60 has a pair of circular openings 71 and 72, which are selectively registrable with detent 67. When the timer mechanism in housing 22 is not operating-Le, it has counted outthe several parts are in the positions illustrated in the drawings; and the detent 67 is engaged in opening 71, so that knob 62 and dial 60 are releasably coupled to one another by the detent.

In use the timer 20 is adapted to be secured by its bracket leg 24, for example, to the bottom edge of the dashboard of an automobile containing a citizen band radio; and the wires 34 are connected to a power source. Let us assume now that the interval timer in housing 22 is a fifteen minute mechanism, and that, if its shaft 28 is rotated (clockwise in FIG. 1) 360, fifteen minutes will be required for the shaft to return back to its normal starting position.

This timer may be set by the attachment of the present invention, however, for any interval less than fifteen minutes, say for a five minute interval, as when it is used with a citizen band radio. To so use the timer, the adjustable arm 41 is pivoted manually until it is positioned as precisely as possible clockwise from zero position (FIG. 3), which is the setting for a five minute operation. The knob 62 is then manually rotated (clockwise in FIG. 1) until pointer 55, which moves with the knob, strikes the stop lug 43 (FIG. 3). This rotates the shaft 28 120 from its zero position.

During the above-described 120 rotation, the detent 67, which projects into the hole 71, causes the dial 60 and block 64 also to be rotated 120. At this position the spring arm 49 is engaging a corner of the land 64 as shown in FIG. 9, and the spring develops a torque which causes the dial 60 to cam the detent out of the hole 71 in the dial into recess 66 against the resistance of spring 68. This allows spring 47 to rotate the dial 60 further in the direction of arrow 74 (FIG. 9), until the spring arm 49 once again engages one of the long sides of the land 64, or the side opposite to that engaged by the arm 49 in FIG. 6.

Thus the dial 60 will be driven one half a revolution, and the pointer 55 will be in registry with the numeral 5 located on the green portion 76 of the dial 60, which now is uppremost from the position shown in FIG. 1). At this time, also, the contacts 57 on the pointer 55 will bev in engagement with the two conductors 31 and 32. This causes the lamp or bulb 56 in the pointer 55 to be illuminated; and the illuminated pointer is in turn viewable through the translucent dial 60. This indicates visually that the radio is in a transmitting period.

As the shaft 28 rotates back to its zero position, driven by the clock mechanism in case 22, the dial 60 is held stationary by the spring arm 49 abutting block 64, but the pointer 55 and the knob 62 rotate backwardly with the shaft v28 towards zero position. During this return movement to zero position the retracted detent 67 slides on dial 60, until the knob 62 reaches start position at which time the detent 67 will snap into hole 72 in the dial 60, once again to couple together the knob and dial. As the pointer 55 approaches zero position, the radially outermost of its contacts 57 rides up over the knife edge 39 onto the insulator 37, interrupting power to the lamp 56, and causing the lamp to be turned off. Substantially simultaneously an audible warning signal in the conventional timer housing 22 is actuated. The shell 21 and casing 22 have a plurality of holes 78 (FIG. 2) formed in their rear, which prevent deadening of the sound; and the operator is warned both visually and audibly, therefore, that the five minute time interval has expired.

To time now the five minute interval during which the radio will be held in standby or non-transmitting status, the knob 62 is once again rotated in a clockwise direction from the position in FIG. 1 until pointer 55 once again strikes the stop lug 43 on arm 41 at approximately 120 from zero position. This time the detent 67, which is now engaged in hole 72, rotates the dial 60 120; and again spring arm 49 causes the dial 60 to continue to rotate an additional 60, thereby to return the red half 77 of the dial 60 to its upper position shown. The timing mechanism in case 22 then again rotates pointer 55 back to zero, and once again the light is turned off and the alarm sounded, but this time to indicate that the idle, nontransmitting period is ended.

If at any time when the timer has counted out the pointer 55 does not register properly with a zero indicium on dial 60, the arm 45 may be rotated slightly around the shaft 28 by means of tab 46. This causes spring 47, which is carried by arm 45, to be adjusted relative to shaft 28 so that spring 47 through its arm 49 adjusts the at rest position of dial 60 relative to shaft 28, to properly set the zero indicium on dial beneath and in registry with the pointer 55.

From the foregoing it will be apparent that the attachment disclosed herein provides a ready means for standardizing the types of interval timers. Standard timers capable of timing a maximum interval of say one hour, can readily be adapted to time out at less than the maximum time measurable by the timer.

By making the block or land 64 on dial 60 triangular instead of rectangular, the operation would be changed from a two-interval to a three-interval operation. Moreover, by employing a pentagonal land 64, the operation can be changed from two-interval to five-interval. With each change in the shape of the land 64, however, the indicia on the dial 60 would have to be altered correspondingly.

While the invention has been described in connection with a specific embodiment thereof, it will be understood that it is capable of further modification, and this application is intended to cover any variations, uses, or adaptations of the invention following, in general, the principles of the invention and including such departures from the present disclosure as come within known or customary practice in the art to which the invention pertains and as may be applied to the essential features hereinbefore set forth, and as fall within the scope of the invention.

Having thus described my invention, what I claim is:

1. An interval time, comprising a timer mechanism having a shaft rotatable in one direction to wind said mechanism, and in the opposite direction to unwind said mechanism,

a graduated dial member,

a pointer member,

means mounting said members on said shaft in operative relation to each other, with one of said members being secured to said shaft for rotation therewith and with the other of said members being rotatable relative to said shaft, means releasably coupling said members together for rotation with said shaft, and means operative upon the rotation of said shaft and members a predetermined distance in said one direction automatically to rotate said other member further in said one direction independently of said one member and said shaft. 2. An interval timer as defined in claim 1, including adjustable means for limiting the rotation of said shaft in said one direction without interfering with said further rotation of said other member.

3. An interval timer as defined in claim 1, including adjustable means for limiting the extent to which said other member rotates beyond said one member in said one direction.

4. An interval timer as defined in claim 1, wherein said other member is a circular dial diametrically opposite halves of which are colored differently from one another, and

means is provided for illuminating said pointer member and one of said halves of said dial, when said shaft is in a wound condition.

5. An interval timer as defined in claim 1, wherein the last-named means comprises a cam secured to said other member, and

a spring interposed between said cam and said shaft and operative to urge said other member further in said one direction after said one member has stopped.

6. An interval timer, comprising a timer mechanism having a shaft rotatable a predetermined distance away from a position of rest to set said mechanism for a predetermined timing interval,

a pointer secured to said shaft for rotation therewith,

a dial rotatable on said shaft and having thereon a plurality of sets of graduations angularly spaced around said shaft, and

means for successively indexing said sets of graduations into operative relation to said pointer, each time said shaft is rotated out of said rest position said predetermined distance,

said indexing means including means releasably coupling said dial to said shaft for movement therewith in one direction only.

7. An interval timer as defined in claim 6, wherein said indexing means includes means operative to disconnect said coupling means and to move said dial relative to said shaft, when said shaft has been rotated said predetermined distance.

8. An interval timer as defined in claim 7, wherein the disconnecting means comprises a cam secured to said dial and having thereon a plurality of plane surfaces at least equal in number to the number of sets of graduations on said dial, and

a spring engaged with one of said surfaces, when said shaft is in said rest position, and operative upon the rotation of said shaft said predetermined distance from said position of rest, to exert on said cam a moment strong enough to disconnect said coupling means and rotate said dial relative to said shaft until said spring engages another of said surfaces thereby to resist further movement of said dial.

9. An interval timer as defined in claim 6, including a pair of arms rotatably mounted adjacent one end thereof on said shaft for limited angular adjustment thereabout,

a stop on one of said arms positioned to engage said pointer, when said shaft has been rotated said predetermined distance from said rest position, and

means on the other of said arms for shifting said dial about said shaft to place one of said sets of graduations into proper operative relation to said pointer.

7 8 10. An interval timer as defined in claim 9, wherein References Cited the last-named means comprises a torsion spring hav- UNITED STATES PATENTS ing a free end extending transverse to said shaft, and said indexing means further includes a many-sided land xi zi g zi 'g Integral with said dial and engaged by Sald free end 5 2,667,921 2/1954 Doyle 58 22 9 of said spring normally to resist movement of said dial relative to said shaft, and operative under the RICHARD B. WILKINSON, Primary Examiner resistance of said free end of said spring to rotate said LAWRENCE R FRANKLIN Assistant Examiner dial beyond said predetermined distance, when said shaft has been rotated said predetermined distance 10 U.S. Cl. X.R.

from said rest position. 58-21.13

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US2249072 *Feb 27, 1940Jul 15, 1941Anabolic Food Products IncElapsed-time indicator
US2656672 *Dec 17, 1947Oct 27, 1953Webber John JInterval timer
US2667921 *Sep 20, 1951Feb 2, 1954Rhodes Inc M HTwo-speed timer
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3648190 *Jan 2, 1970Mar 7, 1972Bruckert Eugene JActive filter
US7465085 *Sep 20, 2006Dec 16, 2008Mcdonough Michael PActivity timer for meditation
U.S. Classification368/108, 368/109, 968/813
International ClassificationG04F3/02, G04F3/00
Cooperative ClassificationG04F3/027
European ClassificationG04F3/02D