US2932702A - Clock-controlled timing apparatus - Google Patents

Description

April 12, 1960 R. F. GREENE ET AL CLOCK-CONTROLLED TIMING APPARATUS Filed Sept. 5, 1958 RADIO RECEIVER lli-l I/VVE/VTORS omeo F Greene Eugene Il POZZey United States Patent() cLocK-coN'rRoLLnD TIMING APPARATU Romeo F. Greene, Forest Park, and Eugene I. Pulley, Lombard, Ill., 'assignors to Zenith Radio Corporation, a corporation of Delaware Application September 5, 1958, Serial No. 759,347

6 Claims. (Cl. 20D-36) these requirements the contact elements are constructed so as to have a maximum amount of spring pressmre urging their mutual engagement and a minimum amount of frictional drag. For `these reasons, `automatic timing control by the use of low torque motors, of which conventional clock motors are notoriously among the weakest, is difficult.

In addition, time-controlled switching devices usually have to permit adjustment of time setting and this gen- -erally' necessitates moving an adjustably fixed contact in relation to a movable contact driven by the clock mechanism. With prior devices when the adjustablypfixed vcontact is rotated in a direction opposite that in which `the movable contact is driven, there is a distinct danger of distorting one or the other and adversely effecting the desired low frictional attributes or positive contact engagement or of displacing the hour hand from its proper position.

Yet it is desirable in clock-controlled devices to provide an adjustment such that time setting may be accomplished in either direction of rotation. An operator usually prefers to execute this function by turning the adjustable element in whichever direction is closest to the desired setting. Precaution must therefore be taken `to minimize the distortion or other deleterious etfects to Vthe contact-s as a consequence of the time setting.

In clock operated radios it has been the custom to mount a clock alongside a conventional radiodial so v adjustments to avoid bending or distorting. Moreover,

the location of the adjustments on the rear of the unit is not entirely satisfactory because the condition of adjustment can, in many cases, be determined only from the clock face.

Accordingly, a principal object of the present invention is to provide a timing switch in which the contact elements effect positive and reliable engagement at the appropriate preset time, while yet presenting low frie-y ICC tional relation of the movable contact element driven by the clock mechanism and its associated adjustably fixed contact.

Another object of the invention is to provide a timing switch that may be adjusted from the front of the mechanism Where both the clock face and the preset position are readily visible.

It is a lspecific object of the invention to provide an improved clock radio characterized by the fact that the alarm set is adjustable from the front of the clock mechanism.

A timing switch, in accordance with the invention, comprises a clock mechanism including minute and hour hands rotatably supported and driven to sweep a clock face area. A flexible contact spring is rotatable with the hour hand and comprises an electrically conductive Strip having a generally V-shaped configuration supported at one of its ends against movement. This conductive strip is supported at its other end for limited motion and its apex describes a generally circular path as the hour hand is driven. A supporting member is provided including a stationary contact disposed in the circular path Vand mounted for movement therealong. Finally, a control knob, mechanically coupled to the supporting member and encircling the clock face area, is provided for adjustably moving the supporting member to locate the stationary contact at any `desired point along the circular path so that the contact spring engages the stationary contact when the hour hand of the clock mechanism assumes a predetermined position.

The features of the present invention which are believed to be novel are set forth with particularity in the appended claims. The organization and manner of operation of the invention, together with further objects and advantages thereof, may best be understood by reference to the following detailed description taken in connection with the accompanying drawing, in the several figures of which, like reference numerals designate corresponding parts throughout, and in which:

Figure 1 is a front elevational View, with portions broken away, of a preferred embodiment of the invention applied to an electrically operated clock-radio mechanism;

Figure 2 is an elevational view of the mechanism of Figure 1 with portions broken away, together with a schematic wiring diagram thereof;

Figure 3 is an enlarged sectional view taken mately on line 3 3 of Figure l;

Figures 4 Aand 5 are similar front elevational detail views of certain portions of the switch mechanism under different conditions of operation and are taken approximately on line 4-4 of Figure 3; and

Figure 6 is a fragmentary sectional View taken approximately on line `6--6 of Figure 3.

Referring now more particularly to Figure 1, the arrangement there represented is the clock portion of a clock-radio. Since the invention resides in that portion of the combination, the radio section has not been shown 'although it is indicated in Figure 2. The clock mechanism includes a face plate 12 having a circular aperture 13 around which are distributed a series of hour markings 60 that constitute reference designations for an hour hand 14 and a minute hand 15. Together these components may be regarded as a clock face area.

The motor, escapement, and driving train mechanism 16 may be either spring wound or electric motor operated but it is assumed, for convenience, that the device is electrically operated by a battery or other power source 50. The drive shaft assembly 21 emerges from a housing `and includes an outermost sleeve 17 that is driven at therateof one revolution per twelve hour-s,

approxian innermost sleeve 18 driven at the rate of one revolution per hour, and optionally, a central shaft 19 driven at a speed of one revolution per minute.

Oneend of drive shaft assembly 21 is supported in a bushing 22 spun over as at 23 or otherwise suitably secured to the housing wall 16 and terminated in a threadedsleeve portion 24. Onto this sleeve 24 there is threadably received a spanner nut 25 the inner surface of which is shouldered as at 26 to abuttingly engage and tighten against a disc of insulating material 27. Between disc 27 and the wall of clock housing 16 there may be installed an electrical contact plate 2S forming part of a control circuit and electrically isolated by disc 27 and a similar but larger insulating disc 29 that is turned under as at 31 to insulate plate 28 from housing 1 6 as well as from bushing 22.

A supplementary insulating plate 32 may be inserted between disc 29 and wall 16 of the housing for the purpose of tightening Contact plate 28 aud maintaining it rigidly in position by means of Spanner nut 25. A flange 33 which extends radially of Spanner nut 25 clampingly retains a supporting member 35 by engaging a flange 34 thereof. Support member 35 is integrally associated by way of mounting screws 36 with an adjustment means for adjustably moving support member 35. This means comprises a cylindrical knob element 37 that extends Vthrough aperture 13 of face plate 12 and together with a transparent crystal 40 encloses the clock face area swept by the minute and hour hands. The knob 37 is provided with an index mark which `may be read in relation to the clock face area for denoting the setting or predetermined position at which the switch is to close. This sirnplilies` time reading to some extent.

Support member 35 is made of plastic or other suitable insulating material and is hollowed out at three circumferentially spaced sections, one of which is desigsection a springy contact leaf 39 'for engaging contact plate 28. The contact leaves 39 form part of a conductive spider which includes a centrally disposed'circula'r disc portion 45 of support member v35 from which ange 34 projects as illustrated in Figures 2, 3 and 4. Referring to Figure 4, it is seen that the leading edge of aperture 43 projects radially inward farther than the trailing edge and constitutes a drop-off shoulder 46 adjacent contact projection 42.

eliminates an indicator hand vfrom the clock tace and `nated 38, for the purpose of accommodating in each such s 'portion 41 snugly conned between insulating member i 27 and Support member 35. Out of the body of spider 41 isstruck a contact projection 42 which extends through an aperture 43 in the flange 34 of support member 35 land is nested in a recess formed in the inner circular A relatively thin, conductive supporting disc 51 is drivetted onto sleeve 17 which carries hour hand 14. On its interior surface this disc has a shallow annular ridge 53. At two spaced points on ridge 53 there jut a pair of anchor posts 54 and 55 which appear in Figures 4 and 5. A movable, flexible contact spring 56 made of a narrow lstrip of'conductive material is bent intermediate its length to have a generally V-shaped conguration including an apex 57, and oppositely extending legs 59 and 61. Of these, leg 59 is significantly longer and is curved involutely having its terminal anchored in post 54. This leg 59 of the spring 56 has a low slope angle respecting its surface immediately preceding apex 57 in relation to that of the course or path 45 over which it travels.

The shorter leg 61 is nearly linear and terminates in a closed loop 62 that encircles anchor post 55 effectively captivating leg 61 but permitting it to have limited movement lengthwise as represented by the length of the loop. This degree of movement permits apex 57 to follow surface'deviations in the portion or raceV 45 provided by member 35. Since the spring 56 is mechanically driven with hour` hand 14, its apex courses a generally circular Apath-en'scribed or deiined by race 45. Accordingly, -apex justrnent manipulation.

fasasa'roaY Y 57 traverses this path, in the direction represented by the arrow in Figure 5, and is driven over shoulder 46. The mounting of spring 56 allows for the involute character of race 45 while the tethering eifect prevents it from being distorted beyond its physical yield point from which it might suifer a permanent deformation. During its travel about the race, spring 56 follows the contour of path 45, dropping off shoulder 46 with a snap action that assures positive contact engagement between apex 57 and stationary contact 42.

Operation The user of a clock-radio constructed in accordance with the present invention makes the time setting adjustment by manually rotating the cup-shaped cylindrical housing or knob 37 clockwise or counterclockwise, to dispose stationary contact 42 at some circumferential location respecting the clock face area 60. If he rotates housing 37 counterclockwise, the encounter between apex^57 of contact spring 56- and drop-off shoulder 46 is gradual andresembles that which takes place during the course of normal clock operation when spring 56, rotating clockwise, drops oli shoulder 46.

If onthe other hand, the operator rotates knob 37 clockwise, shoulder 46 encounters apex 57 of spring 56 abruptly, as illustrated in Figure 5, imposing upon this member a linear force directed tangentially, that causes the spring to bow throughout its curvature. This deforms legY 59 to some extent only for the reason that short leg 61, upon reaching its limit of movement as allowed by loop 62, causes apex 57 to be drawn inwardly. As application of this force is continued, the inward deflection of leg59 reaches a point beyond which the tethering eiect of short leg 61 swings apex 57 radially inward and towards the center of the shaft assembly. Ultimately, apex 57 overrides shoulder 46 whereupon the stored energy in spring 56 snaps apex 57 out of engagement and in a counterclockwise direction to a region substantially beyond the shoulder 46.

When an alarm setting is established, stationary contact 42 is disposed at some point circumferentially of the clock area 60 where it is to be engaged by the movable contact spring 56 during the course of its 12 hour circuit. Specifically, as minute and hour hands 14 and 15 assume a predetermined position corresponding to the time selection established by adjustment of knob 37, apex 57 of the movable contact snaps over shoulder 46 and effects a positive circuit engagement with stationary contact 42. This completes a circuit traceable in Figure 2 from ground through supply battery 50, the radio receiver portion of apparatus 30 to the stationary contact plate 28. From here the circuit is traceable through one or more of the spider leaves 39, through stationary contact 42, movable contact 56, the electrically conductive supporting disc 51 to which movable contact spring 56 is anchored, thence through the metallic portion of the clock mechanism to ground. Y The completion of this circuit results in closing the radio operating circuit, the tuning of which has been pre-arranged. Alternatively, it may initiate any other type of alarm device.

It is to be noted that, in exerting its tethering effect, leg 61 limits the degree of distortion to which leg 59 may become subjected, thereby avoiding distortion beyond the yield point such as would inflict a change in its permanent shape. Also, it preventsthe apex of the spring from becoming twisted in a transverse sense by maintainingzit parallel in cooperation with the permanent anchor at post 54.

It is further to lbe noted that in accordance with the linvention herein disclosed an operator is enabled to set 37 while being aible, through transparent crystal 40, to

observe closely and conveniently both ythe positions of the clock hands as well as `the'precise effects of his ad- It is not necessary to limit users of this type of apparatus in respect to the direction of rotation of the setting knob. The user may rotate the knob clockwise or counterclockwise, whichever direction he chooses or whichever happens to be the shortest route towards attaining a new setting location.

It is also to be observed that with the application of the invention to combination clock-radio units, it is no longer necessary to provide long regulating spindles extending through the width of the radio housing.

While a particular embodiment of the invention has been shown and described, it will be obvious to those skilled in the art that changes and modifications may be made without departing from the invention in its broader aspects, and, therefore, the aim in the appended claims is to cover all such changes and modifications as fall within the true spirit and scope of the invention.

Y We claim: Y

l. A timing switch which comprises: a clock mechanism including `minute and hour hands rotatably supported and driven to sweep a clock face area; a flexible contact spring rotatable with said hour` hand comprising an electrically conductive strip of generally V-shaped configuration supported at one end against movement, supported at the other end for limited motion, and mechanically driven with said hour hand to describe with its apex a generally circular path; a supporting member including a stationary contact disposed in. said circular path and mounted for movement therealong; and a control knob mechanically coupled to said supporting member and encircling said clock face area for adjustably moving said supporting member to locate said stationary contact at a desired point along said path sothat said contact spring engages said stationary contact when said hour hand has assumed a predetermined position.

2. A tim-ing switch ywhich comprises: a clock mecha-l nism including minute and houa hands rotatably supported and driven to sweep a clock face area; a ilexible contact spring rotatable with said hour hand comprising an electrically conductive strip of generally V-shaped conguration supported at one end against movement, supported at the other end for limited motion and meohanically driven with said hour hand to describe with its apex'a `generally circular path; a supporting member including a stationary contact disposed in said circular path and mounted for movement therealong; and a transparent adjustment knob coupled to said supporting member and surrounding said clock face area for adjustably moving said supporting member to locate said stationary contact at a desired point along said lpath so that said contact spring engages said stationary contact when said hour hand has assumed a predetermined position.

3. A timing switch which comprises: a clock mechanism including minute and hour hands rotatably supported and driven to sweep a clock face area; a flexible Contact spring rotatable with said hour hand comprisingan electrically conductive strip of generally V-shaped configuration supported at one end againstmovement, supported at the other end for limited motion only, and describing with its apex a generally` circular path; a support member having a generally,cylindrical section enscribing said path and against-which said apex is urged, a stationary contact carried by said support member in adjustably fixed position withrespect to said path;

land a transparent adjustment knob coupled to said supporting member and surrounding said clock face area for adjustably moving said support member to locate said stationary contact at a desired point along said path so that said contact spring engages said stationary contact when said hour hand has assumed a predetermined position.

4. A timing switch which comprises: a clock mechanism including minute and hour hands rotatably supported and driven to sweep a clock face area; a flexible contact spring rotatable with said hour hand comprising an electrically conducted strip of generally V-shaped configuration supported at one end against movement, supported at the other end tor limited motion only, and describing with its apex a generally circular path; a rotatable contact assembly including a cylindrical portion enscribing said path, a conductive spider having radially extending arms for engaging a stationary contact plate, and an adjustably iixed contact portion extending into said circular path; a stationary contact plate in continuous engagement with said fixed contact for all positions of adjustment thereof for extending a circuit connection therethrough; and means coupled to said support member and surrounding said clock face area for locating said fixed contact along said path so that said contact spring engages said iixed contact when said hour hand has assumed a predetermined position.

5. A timing switch which comprises: a clock mechanism including minute and hour hands rotatably supported and driven to sweep a clock face area; a flexible Contact spring rotatable with said hour hand comprising an electrically conductive strip of generally V-shaped coniiguration, one end of which is curved and anchored against movement, the other end of which is tethered for limited movement only, and the apex of which is springably urged by said anchored end to pursue a generally circular path; a support member' including a cylindrical portion which cnscribes said circular path and has a dropoit shoulder; a stationary contact positioned adjacent said shoulder for engagement by said rotatable contact; and means coupled to said support member and surrounding said clock face area for locating said stationary contact along said path so that said rotatable Contact engages said stationary contact when said hour hand has assumed a predetermined position.

6. A timing switch which comprises: a clock mechanism including minute and hour hands rotatably supported and driven to sweep a cloclciace area; a support member dening a generally circular path and a dropoff shoulder at one point in said path followed by a stationary contact, said support member being rotatable alternatively in clockwise and counterclockwise directions for thereby adjusting the circumferential disposition of said drop-orf shoulder and Contact; a ilexible contact rotatable clockwise with said hour hand and comprising an electrically conductive strip of spring metal generally V-shaped and thus providing an apex and divcrging legs, one of said legs being anchored and exerting a force upon said apex for urging it into engagement with said path, shoulder and stationary contact, the other of said legs being tethered for restraining said apex against distortion beyond the yield point of said one leg during the clockwise adjustable rotation of said support member; and means for manipulating said support member from a position frontward of said clock face area to locate said stationary contact at a desired point along said path so that said Contact spring engages said stationary contact when the hour hand assumes a predetermined position.

References Cited in the le of this patent UNITED STATES PATENTS Re. 23,733 Smith Feb. 16, i954 1,797,072 Caraba Mar. 17, 1931 2,310,090 Kalaydjian Feb. 2, 1943 2,498,805 Gurevsky Feb. 28, 1950 2,508,896 Smith May 23, 1950 2,767,271 Mucher Oct. 16, 1956 2,790,862 Montgomery f Apr. 30, 1957

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