US3073919A

US3073919A - Lapsed timer

Info

Publication number: US3073919A
Application number: US40862A
Authority: US
Inventors: William E Holder
Original assignee: Individual
Current assignee: Individual
Priority date: 1960-07-05
Filing date: 1960-07-05
Publication date: 1963-01-15
Anticipated expiration: 1980-01-15

Description

3 Sheets-Sheet 1 W. E. HOLDER LAPSED TIMER Jan. 15, 1963 Filed 'July 5, 1960 Jan. 15, 1963 w. E. HOLDER 3,073,919

LAPSED TIMER Filed July 5, 1960 3 Sheets-Sheet 2 INVENTR. L//LL/AM f. /oLosQ 14a/Caz f Jan. 15, 1963 w. E. HOLDER 3,073,919

LAPSED TIMER Filed July 5, 1960 3 Sheets-Sheet 3 INVENTOR. //LL//w 5 #0405? AL, 1ML Y @t A oeh/sys United States Patent Oiice 3,073,919 Patented Jan. 15, 1963 3,073,919 Ll-PSED TMER William E. Holder, Pleasant Valley, N.Y., assignpr t0` Mendel Brown, Fishkill, N. Y. Filed .lilly 5, 1960, Ser. No.. 49,552 12 Claims. (Cl. 21m- 33) This invention4 relates to a lapsed timer and, as shown herein, specifically to a lapsed -timer for controlling an electric switch mechanism, that is to say', af lapsed timer which after an interval oftime will either open or close` an Aelectric circuit.

In general, present-day commercial lapsed time switches are of two types, one utilizing a thermally responsive device such as a bimetallic element for the lapsed time' mechanism, and the other utilizing a clock.

The rst of these, that is to say, a' lapsed time switch which employs a bimetallic element, has two major drawbacks. Because it is' actuated by -a heating coil that engendcrs ilexing movement of the bimetallic element over a period of lapsedptime, the lapsed time mechanism is affected -by changes in ambient temperatures. In the winter the time which lapses before operation of the switch is longer and in the summer it is shorter. Moreover, this type of lapsed time mechanism, in addition to its inaccuracies caused by temperature fluctuations, is not capable of providing a reasonably accurate extended lapsedA time period;` that is to say, unless it isv made-unduly bulky, and unless variations in lapsed time are permitted to differ widely, the lapsed time period cannot exceed more than a few seconds, e.g., up to about ten' seconds. The only virtues of this type of lapsed time mechanism areits comparative simplicity, low cost and small size which, however, are quickly lost if an eifort is made to substantially length-en the available lapsed time period, to permit accurate variations in the lapsed time period over a broad range, and to counteract the eiect of changes in ambient temperature. v

The second type of lapsed timer, i.e., one using a clock to measure 4the passage of time, is inherently costly, bulky and complex. Either an electric or a mechanical clock drive must be employed and neither of' these is small or inexpensive. I

It is an object of my present invention to provide a lapsed time mechanism having the advantages of both the former types of mechanism, but Ithe disadvantages of neither; that is to say, a lapsed time mechanism which is compact, relatively simple, relatively inexpensive to make, constitutes relatively Afew parts, is comparatively insensitive to changes in ambient temperature, is accurate, can provide, if desired, comparatively long lapsed time periods, eg., up to a few minutes, and can have the lapsed time period adjusted over ya wide range.

It is another object of my invention to provide a ,rnechf anism of the character .described which is of Sturdy, feel-L proof and rugged construction.

Itis another object af my invention te Provide a'- mechanism of the character described which is readily adapt-v able for use in controlling an electric make or break connection, i.e., an electric switch mechanism.

It is another object of my" invention to provide a law cost, reliable, small, lapsed time elec-tric switch of the character described which easily can 'be fitted into electric appliances and devices, eg., wall switches, within the limited space that is allotted to such structures. More specifically, it is well known that a wall switch must'` be received within a conventional electrical wall box, and that whenever a switch is manufactured, it must be made having in mind the internal sizes of hundreds of millions ofl such wall boxes which valready have been installed. The switch of my invention easily can be made suciently small for positioning within such extant wall boxes without in any way militating against its eiciency of operation.

It is an ancillary object of my invention -to provide an electric switching mechanism of `the character described` which is capable of particularly fast mak-e or breakop' eration of the switch.

It is another ancillary object of my invention to provide an electric switching mechanism of the character ydescribed which is readily adaptable to any type of manual operation, e.g., operation by rotation, operation by an oscillating arm or operation by push buttons.

Other objects of my invention in part will be obvious and in part will be pointed out hereinafter.

My invention accordingly consists in the features of construction, combinations of elements and arrangements of parts which will be exemplified in the constructions hereinafter described and of which the scope of applica -tion will be indicated in the appended claims.

IIn the accompanying dra-wings in which are shown various possible embodiments of my invention,

FIG. 1 is a vertical sectional view through a wall switch constructed in accordance with my present invention;

FIG. 2 is a horizontal sectional view through said switch, the same being taken substantially along the line 2--2 of FIG. l;

FIG. 3 is an exploded view of the parts constituting the nexus of my invention as embodied in the particular switch illustrated;

FIG. 4 is a vertical transverse sectional View through the lapsed time mechanism, the same being shown in'a position corresponding to the Oi position of the electric switch mechanism;

FIG. 5 is a view similar to FlG. 4, but illustrating the lapsed time mechanism in a position correspondingI to On position of the electric switch'mechanism;

FIG. 6 is a view similar to FIG. 4, but showing the lapsed time mechanism in a Preparation position which precedes the initiation of a lapsed time operation, the electric switch at this time being in O`n position;

FIG. 7 is a view similar to FIG. 4, at the beginning ot' the Lapsed Time position, sometimes hereinafter referred to as a Leak position, the electric switch at this time likewise being in On position;

FIG. 8 is a perspective View of the parts of the electric switch mechanism, the same being' shown in Oiln position corresponding to the FIG. ,4 position of the lapsed time mechanism.

FIGS. 9, l0 and ll are views similar to FIG. 8, but

` showing the switch parts in On position and correspondtime mechanism embodying a modified form of electric switch mechanism; and

FIG. 14, 15, 16 and 17 are sectional views taken substantially along the line 14-14 of FIG. 13 and showing the switch parts in positions corresponding respectively to the FIGS. 4, 5, 6 and 7 positions of lthe lapsed time mechanism;

FIG. 18 is a face View of a switch embodying a modilied form of my invention wherein a different arrangement is employed to'vary the lapsed -time period;

FIG. 19 is a partial side view of the switch shown in FIG. 18 and illustrating, in particular, the external parts of the means that vary the lapsed time period; and

FIG. 20 is a perspective View of the timing cam which is the selectively settable part of the aforesaid means.

Referring now in detail to the drawings, and more particularly to FIGS. 1-12, the reference numeral 28 denotes a lapsed time switch constructed in accordance. with and embodying my invention, said switch being designed and dimensioned for reception in a conventional Wall switch box of the type adapted to receive a standard switch. 'I'he switch is of such physical configuration and size that it approximately matches the configuration and size of a standard straight-forward switch, i.e., nonlapsed time switch, which ordinarily would be disposed within such a wall box.

In general, the switch includes a lapsed time mechanism 22 the construction and operation of which will be explained in detail hereinafter. Additionally, the switch 28 comprises an electric switch mechanism 24 which is operated by the lapsed time mechanism. Alternate switch constructions, one 24 of which is shown and described herein (see FIGS. l3l7), can be used in lieu thereof. Optionally, and as shown in this embodiment of my invention, the switch further includes a mechanism 26 for varying the lapsed time period and for rapidly terminating the same. An alternate lapsed time varying mechanism 26" also is shown herein (see FIGS. 18- 20). The three

foregoing mechanisms

22, 24, -26 comprise the heartof the invention as embodied in the switch 20. In addition, a suitable operating means 28 is included to provde a convenient arrangement for manually manipulating the switch to its Off, On, Preparation and Lapsed Time positions.

More particularly, the switch 20 includes an outer casing 30 which conveniently is of cylindrical transverse cross-section. The interior of the casing is hollow for accommodation of the various operating parts. Said casing is fabricated from an electrically non-conductive material, as for example, a phenol-formaldehyde con-v densate resin, this type of material being suitable for all of the various electrically non-conductive parts herein after to be described in connection with the switch.

The rear of the casing is closed by a back Wall 32. The front of the casing is open but is blocked by a lid 34 of electrically non-conductive material and generally disc-like shape which is tightly fitted Within the front of the casing and is securely held thereto in any suitable fashion, as for example, by an autogenous junction if the switch is not to be opened after sale thereof, or by pins, screws, or other removable fastening means if the switch is to be repairable.

The lid is formed with an integral, forwardly extending semi-circular, flat-sided, diametrically positioned protwberance 36 the opposite sides of which serve as gibs (see FIG. 2) for oscillatory inwardly facing flat parallel surfaces of a switch arm 38 that constitutes the actuating element of the operating means 28. -The switch arm likewise is made of electrically non-conductive material. It includes a manually manipulative -tab 40 at the very front of the switch 20. A pair of

arms

42, 44 extend rearwardly from the tab and terminate at inwardly directed broad

circular studs

46, 48. The inner faces of these studs are flat and parallel and are in oscillatable sliding engagement with the side faces of the protuber- 4 ance 36. The center of the lid 34 is semi-circularly grooved out as at 56 on opposite sides of the protuberance 36 to accommodate the circular sides of the

studs

46, 48.

In order to retain the switch arm 38 in position on the lid with its studs bearing against opposite faces of the protuberance 36 and riding in the grooves 56 I provide a semi-cylindrical stationary electrically non-conductive retainer shield S0 in concentric position with respect to the protuberance 36 and the

studs

46, 48. The ends of the shield 50 are butted flatly against the front face of the lid 34 (see FIG. 1) and are firmly fixed in that posi-- tion in any suitable manner, as for instance by screws 52.. The central inner surface of the shield closely follows the extzrnal periphery of the protuberance 36 as clearlyv can be seen in FIGS. 1 and 2. At the sides of the shield the inner surface thereof is semi-circular and rotatably bears against the

studs

46, 48, said studs being grooved out as at 54 to snugly receive stud flanges 55 at the sidesof shield whereby to prevent axial shifting of the switchA and the lower part of the front face of the lid, and theother end of which is defined by abutment of said taby 40 with the lower edge 58 of an arcuate electrically non-l conductive stop 60 operationally integral with the shield 5.0. The stop, for example, may be cemented to said shield.

One of the studs, e.g., the stud 46, is provided with a concentric bevel gear 62 which is made of electrically' non-conductive material, although as will be appreciated, since this gear is concealed, it optionally may be fabri cated from metal. The gear 62 meshes with a face gear 64 formed in one piece with and at the center of the front surface of a positioning wheel 66 of electrically nonconductive material.

The positioning wheel includes a cylindrical tubular' hub 68 which is rotatable about a rearward cylindrical tubular extension 70 on the stationary lid 34 so that the angular orientation of the positioning wheel with respect to the casing 30 will be varied by up or down movement of the switch arm 38, the vertical movement of said arm being translated into angular movement of the wheel via the train of meshing gears 62, 64. The hub 68 is fashioned with an internal transverse partition 72 in one piece thercwith. The center of the partition extends forwardly to provide an inwardly facing socket 74 and also to form the gear 64. It will be seen that the wheel 66 thereby is provided with an annular space 76 between the center of the partition and the hub 68 in which space the stationary, tubular extension 70 of the lid 34 is rotatably received.

Extendng rearwardly from the back surface of the positioning wheel 66 is a positioning lug 78 (see FIG. 1,

. 3-7) the function of which soon will be clear.

The lapsed time mechanism 22 comprises a hollow hermetically closed chamber provided, for example, by means of ahollow cylindrical imperforate drum 82 of electrically non-conductive material. A body 84 of liquid is located within this chamber. In the operation of the lapsed time mechanism, as will be apparent later in this specification, said liquid flows through an orifice, e.g.,-

a restricted pas:ageway, and the rate of flow in part determines the periodof time lapsed before the switch mechanism is openedor closed automatically. Accordingly, various liquids may be utilized, bearing in mind the general range of time lapse desired. For example, if the lapse of time is to be in a range of acomparatively flew seconds, e.g., ten to twenty seconds, the liquid simply may be water anda comparatively tiny, but non-capillary, orifice used. Alternatively, if it is desired for manufacturing purposes vto have a shcrt time lapse, but not to use such a tiny orice, a somewhat less easily owing material may be employed, e.g., a syrup thinned with water, such `for instance, as corn syrup diluted with water. If still greater time lapses are desired, even vless easily flowable materials are utilized for the liquid, for instance, silicone oils of different viscosities depending upon the range of lapsed time desired, or syrups thinned with other liquids, eg., corn syrup thinned with vinegar. It also is within the scope of my invention to employ an entirely organic lluid, eg., a mineral, and therefore stable, oil the viscosity of which is brought into any desired range by the addition of an organic solvent, eg., gasoline, to thin the oil to such a point that the desired length of time is taken for a certain amount of lluid to flow through a non-capillary orite or passageway of predetermined size.

The chamber within the hollow drum 82 is divided into two operationally effective eccentric compartments A and B, three physical components being utilized to effect this division. The first of the components is a chordate partition 86 which extends from a part of the circumference of the inn `r periphery of the drum to another part thereof along a minor chord of the circle constituting the inner transverse cross-section of the drum. The operating chamber 88 at the major side of the chordate partition is the one in which the liquid 84 is present and which is divided into the two compartments A and B. The vacant chamber 90 on the other side of the chordate partition is non functional and preferably is empty to minimize the moment of inertia of the drum. The partition l86 extends axially of the drum from end to end (front to back) thereof.

The second physical divisive component is an internal center post 92 which likewise runs from end to end of the drum and desirably is hollow. The ,center post and the partition 85 are in one piece with the drum; moreover, the center post touches the partition so that in combination with the partition it initiates the division of the operating chamber 88 into the t-wo compartments A and B. This division is completed by the third divisive component which is in the form lof an outwardly extending longitudinal ange 94 in one piece with and protruding from the center post 92. The thus formed compartments are eccentric with respect to the axis of rotation of the drum.

It will be quite clear from the drawings that the tip, i.e., outer edge, of the longitudinal flange 94 is remote from vthe nearest adjacent portion of the inner peripheral sur;- face of the drum whereby to provide a gap, opening, or passageway 96 of substantial area through which, under certain conditions hereinafter to be described in detail, the liquid 84 can flow freely and rapidly, i.e., without noticeable restriction, between the two compartments.

Furthermore, the drum includes, in addition to the ,large passageway 96 between the compartments A and B, Ywhich passageway is, so to speak, a peripheral passageway, i.e., a passageway the long way around over the inner peripheral surface of the drum between the compartments, a second passageway 93 between said cornpartments A and B, the second passageway-being below the tip of the flange 94. This second passageway is a restricted passageway, that is to say, it is a passageway which is small enough, taking into account the volume and lluidity of the liquid 84, to so restrict flow of the liquid from the compartment A to compartment B, when the former is uppermost with liquid therein, that a nite length of time in the order of the desired lapsed time will be required for approximately one-half of the body of liquid to flow from said one compartment to the other through said restricted passageway. ln other words, the passageway 98 forms a connection between the two compartments which connection includes an orifice small enough, but non-capillary, to restrict tlow of liquid therethrough and thereby incur the desired lapsed time period.

In the 'form of lthe invention now being described the passageway 98 conveniently is of uniform diameter throughout, the diameter being approximately 0.03 inch. It is to be understood, however, that this particular `dimension merely has been given as exemplicative and is not to be construed as a limitation upon my invention. Said passageway preferably is remote from the top of the flange 94 and desirably is immediately adjacent the partition 8.6, eerutming alone the 20.11 0f illnstion between said partition and the center post 92.

It will be appreciated without going into detail at this point, although it will be kexplained subsequently herein, that a given angular position ofthe drum corresponds 'to one condition of the electric switch mechanism, eg., Off, and another position of the drum corresponds to the opposite condition o f the electric switch mechanism, i.e., "On. It further will be appreciated that if the drum is properly manipulated, it can be set in still another position which is the Lapsed Time or Leak position and that if left in this position long enough, the drum will revert to its iirSt, i.e. starting, position. Moreover lit will presently be seen that prior to setting the drum in Leak position it tirst is set -ina Preparation position; and that the electric switch mechanism must remain in its said opposite condition, i.e. On while the drum is in Preparation and Leak positions and until the drum swings back to its starting position.

In FIGS. 4, 5, 6 and 7 I have illustrated these vario-us positions of the drum, i.e., Offf On, Preparation and Leak positions in such respective order, whereby to facilitate understanding of the operation of vmy 1invention and I will interrupt thedetailed description of the switch Y20 at this point in order that the sequence of operations of the lapsed time mechanism 22 may more readily be understood.

In RIG. 4 the compartment A is shown to be uppermost `and the compartment lE to be lowermost. The divisive flange 94 is approximately horizontal. The body vof liquid S4 is entirely within the compartment B and -is approximately centered on the periphery thereof so that the drum is in substantially stable equilibrium. When the drum 82 is in this position the electric switching mechanism `2d is in Off condition so that said drum position is referred toas the Off position. If in any suitable manner the drum 82 now is rotated in a clockwise direction, as viewed in FIG. 4, i.e., in the direction o f the arrow C, through approximately the electric switching mechanism 24 associated with the lapsed time mechanism y22 associated with the lapsed time mechanism 22 will be Vturned to On position.

This 120 change in drum position is shown in FIG. 5 The drum is turned to this position by means of the vpositioning wheel 66 and the positioning lug 78. The positioning wheel is oscillated to the desired extent by verti- 4cal movement of the manually operative tab iti of the switch arm 38. The tab is brought down a little more than half way from its extreme top position to its extreme l`bottom position to effect such movement and through the 'meshing gears 62, 64 brings about the requisite arcuate movement of the positioning wheel 66. Thus, by moving the switch handle from its upper-most position to a lower, but not its lowermost position, the drum will be turned `from a position (FIG. 4) cor-responding 4to Off for the electric switch mechanism to a new position (PIG. 5) corresponding to On for the electric switch mechanism.

By returning the drum in a counter-clockwise direction back to o r substantially toward the first (FIG. 4) position, the electric switch mechanism will be returned to O l position. Thereby, the switch 120 can be utilized `as a Yperfectly normal switch simply by moving the manually operative tab ,40 of the switch handle from its Off upper position to its On intermediate position which is clearly marked by coincident visible indicia on the tab and protuberance or is sensed by a spring loaded ball on the protuberance 36 entering an indentation in the switch handle at On position (see FIG. l). As the drum moves between these Off and On positions (FIGS. 4 and 5) in either direction the liquid simply rwill flow in one direction or another between compartments A and B around the inner periphery of the drum through the large unrestricted passageway 96.

In order to secure lapsed time operation the drum is moved from its On position, shown in FIG. 5, still further in a clockwise direction, as indicated by the arrow D in FIG. 5, to a new angular Preparation position shown in FIG. 6. Physically this is accomplished by depressing the manually operative tab 40 of the switch handle to its extreme lowermost limit whereby to dump the liquid through the passageway 96 into the comparttment A. Next the drum is turned in a counterclockwise direction as indicated by the arrow E in' FIG. 6 to the angular Leak position shown in FIG. 7. Such reverse Imovement is performed by restoring the switch handle to its extreme upper limit in which it abuts against the lower edge of the stop 60.

The positioning lug turns the drum by abutment against one or the other of two angularly spaced fingers 10061, .100b extending forwardly from the front face of the drum. It will 4be apparent that since the fingers dila, 100b are spaced aparteither one, but not both, of the fingers can at one time control the Iposition of the drum, and that when the switch handle is moved from the top to the bottom of its travel and then back to the top the lug 78 first will engage the finger 100b to turn the drum in a clockwise direction, then said lug will be reversed -to disengage the finger 100b and moved toward the finger 100e: until it engages the same, and finally said lug will move the finger 100a, and thereby the drum, in a counterclockwise direction-until the drum reaches the Leak position of FIG. 7. In this latter position the drum is free when so motivated to resume its turning movement in a counterclockwise direction until it reaches Off position as indicated in FIG. 4. During this last movement of the drum the finger 100a moves away from the lug 78 and the finger 100b moves toward but not into engagement with said lug in the direction of the arrow F (see FIG. 6).

As the Adrum turns from the Preparation position indicated -in FIG. 6 to the Leak position indicated in FIG. 7 the mass of liquid 84 in the compartment A will be trapped between the divisive flange 94, a peripheral portion P of the drum and that part of the chordate partition 86 which aids in defining the compartment A. The position of the trapped liquid at the beginning of the lapsed time position is shown in FIG. 7. The level of the liquid is lthen adjacent the tip of the flange 94. I-t further will be observed by inspection of FIG. 7 that in the Leak, i.e. Lapsed Time position of the drum the passageway 98 with the restricted orifice has the end thereof which leads from compartment A higher than the end which leads into compartment B, and preferably all parts of this passageway in such position are below the entrance level of the passageway into compartment A. This means that, providing the passageway is not of capillary dimensions and, of course, the passageway is not made this small, the liquid 84 will flow through said passageway from compartment A into compartment B. The flow is gradual, the length of time which it consumes depending 'upon the size of the restricted orifice and the fluidity of the liquid 'as indicated earlier herein.

It will be clear from inspection of FIG. 7 that the drum with its contained liquid in eccentric compartment A is .in unstable equilibrium when in Leak position and that there is a consequent tendency engendered by the off-center location of the liquid mass to turn Ithe drum in a clockwise direction opposite to the `direction Fshown in said FIG. 7 However, the torque thus provided 4is not sufficiently great to spin the drum because it 'is applied to the positioning lug 78 which is connected thro-ugh the

gear train

62, 6 4 to the switch handle 38 and there is enough static friction in the bearings for the switch handle 8 and gear 64 to prevent such torque from oscillating the switch handle. l

Eventually enough liquid will flowthrough `the restricted passageway 98 to place the drum in neutral equilibrium with the torque of the liquid which has found its way into eccentrically located compartment B balancing the torque of the liquid still remaining in compartment A. As the flow continues through the orifice the mass of liquid in eccentric compartment B increases and begins to exertva continually greatertorque tending to turn the drum in the counter clockwise direction as viewed in FIG. 7. It will be observed that this torque is not exerted against the positioning lug due to the lost motion spacing between the fingers 100a and 100]). The only force opposing movement of the drum under the infiuence of the accumulating mass of liquid in the eccentric com partment B is the restraining torque created by static friction in the bearings for theA drum. These bearings are designed to minimize static friction so that a certain time after the two bodies of liquid in the two compartments A and B have passed through neutral equilibrium to a condition of reverse unstableequilibrium, the torque exerted will be sufficient to start to turn the drum inthe direction of the arrow E. At first therotation will be slow, but the drurnwill gradually pick upspeed and even while the liquid continues to fiow through the passageway 98 it will start to spill over the tip of the divisive flange 94 which acts for the moment as a Weir, thereby increasing the rate of transfer of liquid into comportment B and increasing the rate of spin of the drum until finally all of the liquid flows freely over the fiange and the drum will turn back to and come to rest at or about the Off position indicated in FIG. 4. v

Because the flow of the liquid through the restricted passageway is not noticeably modified by changes in ambient temperature variations, any variation in room temperature will not appreciably affect the operation of my device. In addition, since by proper selection of a liquid and a size of restricted passageway a substantial lapsed timev can be obtained, my device is not restricted to short lapsed times as are bimetallic timers. Moreover, it readily will be appreciated that the drum with its two eccentrically disposed compartments is a simpler mechanism and is less expensive7 can be made smaller and is more foolproof and sturdier than a clock mechanism.

As has been apparent from the foregoing description of the operation of the lapsed time mechanism 22, suitable meansis included to mount the drum 82 for rotation about its axis of symmetry, i.e. the longitudinal axis of the center post 92. Two such means are included at opposite ends, i.e., the front and back ends, of the drum. The rotatable supporting means at the front of the drum constitutes a centrally located forwardly projecting circular protuberance 102 which functions as a journal.

The stationary` bearing for said journal is the socket formed at the rear end of the hub 68 in the space between the extreme rear edge of the hub and the inset partition 72. It is within the scope of my invention to minimize friction at this point in any conventional way, if the same is necessary. I have found that the static friction contact between two smooth phenolic condensation resin surfaces is sufficiently small to allow the drum to turn from Leak toward Off position when the mass of liquid in the compartment B is somewhat larger than the mass .of liquid in compartment A. However, even this friction can be reduced, if desired, by the use of conventional anti-friction means such as a roller bearing or a material with a good slip coeflicient, e,g. Telion.

j The rotatable supporting means at the back of the drum comprises a metal plug 104 imbedded at the center of the back wall of the drum. The rear end of the plug is formed with a conical seat that is'engaged by the needleshaped tip 106 of a 4metal shaft 10S, the back end of which is threaded in a tapped bore 110 in a central boss 112 integrally formed with the back wall 32 of the casing.

amante The rear tip of the shaft 108 is slotted as at 114 to enable the shaft lto be turned, for example, with a screw driver, so as to provide a proper amount of play in the mounting for the drum.

The electric switch mechanism 24, the actuation of which to open or close a circuit depends upon the angular position of .the drum 82, may be of any suitable type, one such mechanism being illustrated in FIGS. l-3 and 84.11, and a variation 24' in FIGS. l3,-l7. The switching mechanism 24 includes a pair of

stationary contacts

116, 118 having bases `120 secured to the lower portion of the casing 31) and upwardly extending resilient electrically conductive arms at the tips of which are secured contact discs 122. A bridging bar 124 of Stiff electrically conductive material is mounted in a stationary non-conductive sleeve 126 extending forwardly from the front end of the boss 112 co-axially of the shaft 168. Suitable means is included to permit movement of the bridging bar parallel to the axis of `revolution of the drum. To this end, the bridging bar extends through and is rigidly fastened to an electrically conductive cylindrical plug 127 which is axially slidable within the bore of the sleeve 126. Moreover, said sleeve 126 includes a pair of diametrically opposite axial slots 128 (see FIG. 2) through which Athe bridging bar 1124 extends so as to permit it to span the space between the kcontact discs 122. The plug 127 is movable axially between two extreme positions. The foremost extreme position is shown in FIGS. 1-3 and 9,-,11. In this position, the bridging bar contacts the dises 122 so that the switch mechanism 24 is closed, i.e. .On.. In the other extreme position of the bridging bar and plug, the ends ofthe bridging bar are spaced from the discs to open-the switch. The second position is shownin FIG. 8 and movement between said position is permitted by the slots 128.

In order to translate change in angular position of the drum into change in axial position of the plug, i.e., to open or ,close lthe switch mechanism, I provide, as shown in FIGS. l-3 and 8411, a simple transduction mechanism which offers only a small resistance to the torque that yrotates the drum at the end of a lapsed time period. Said mechanism constitutes two axially aligned

magnets

13,8, 1,32. The magnet 132 is fast to the drum and the magnet 130 is fast to the plug. Since magnets create tensor forces, change of angular position of either magnet relative to Vthe other will engender either a repulsive or an attractive force. More sp'ecifically,.eac h vof the

magnets

130, 132 conveniently is in the form of a thin disc having a central perforation for passage of the shaft 108. The magnet 130 is adhered to the frontend 4of the plug 127 and the magnet 132 is tightly held in a registered short sleeve 134 extending rearwardly from the back wall of the drum 82. The magnetic discs are fabricated from a permanently magnetizable material and are permanently mag- IletiZed. Preferably, `strongly magnetizable materials are l1 1sed, as for instance Alnico 1V or V which are metallic alloysJ or a ceramic magnetic material. The. two dises are permanently magnetized to provide definite north and South poilesV 'irl each, as .indicated in FIGS. 8-11. It will be obvious that when the discs are arranged with opposite poles approximately in juxtaposition. as shown aFIGS- 9-.11J the magnets are attracted to one anothers thereby pulling the bridging 'bar toward the dises 1221; and when the drum rotates approximately 180, like Poles will be 'brought into juxtaposition, as indicated irl FIG. 8, thereby creating a repulsive force which urges t the bridging bar away from the contact discs 122 to open the switch.

In the absence of the means y26 rfor varying the lapsed time period and for abruptly terminating the same, the drum 82 will, for any given"Leak position and without noticeable variation for changes in ambient temperature, always take substantially the same length of time to terminate a lapsed time period. Moreover, when the drum .ultimately swings away Vfrom its Leak position toward its fOi'f position. the. angular .movement Vis rather Slow until almost the end of the movement when the remainder of the liquid spills over the top of the flange v94. Although such fixed time period and slow opening or closing of the electric switch mechanism are satisfactory for many uses, if it is desired to vary the lapsed time period, and to abruptly terminate the same, i.e., terminate the same with a very quick swinging movement of the drum, a means such as the means 26 is employed.

The

means

2,6 includes three components, to wit, a first permanent magnet 136, a second permanent magnet 138 and an adjusting spindle 148 o n which the magnet 138 is fast. The two magnets ,136, 138 conveniently are in the form of cylindrical discs, preferably of the same materials as are employed for the cylindrical disc mage nets Y131), 132. Said two magnets 136 138 are in registry and are concentrically disposed with respect to the axis of rotation of the drum 82. The magnetic disc 136 is fast within a socket formed in the front wall of the drum within the protuberance l102 (see FIGS. l and 2). The other magnetic disc 138 is rotatable within the socket 74 inside the hub 68 of the positioning wheel, being juxtaposed to the magnet 136. The two magnets arel placed as close together as is possible without interfering with rotation of the drum, and while still permitting a slight axial movement of the disc 138 when the spindle 140 turns. The

magnetic discs

136, 138 have definite north and south poles. The spindle 141i extends through registered bores in the stationary semi-circular protuberance 36 and shield Si), its outer end being formed with a slot 142 to receive a screw driver. The bore in the protuberance is tapped and meshes with a threaded part of the spindle. The magnetic disc 138 is so angularly oriented within the rotary socket 74 (the disc 138 does not turn upon movement of the tab 40 or drum 82) that when the drum 82 is in Off position (FIG. 4), dissimilar poles of the two magnets are in registration. However, when the drum is in its Leak position, dissimilar poles of the two

magnetic discs

136, 138 are angularly remote from one another (approximately in quadrature) and hence do not exert a marked mutual attraction. But, as the drum rotates upon a shift in balance of the liquid within the compartments A and B, dissimilar poles eventually will reach relative positions such that they start to exert a marked mutual attraction. As this occurs, the poles rapidly move toward one another, thereby swinging the drum rapidly and abruptly terminating its movement to Off position.

Varying the angular orientation of the magnetic disc 138 by turning the spindle 140 changes the angular spacing between the two magnetic discs in Leak position so that it will take a longer or a shorter span of time, as the case may be, for the drum to reach a position in which the magnetic attractive forces pull the drum to Off position. ln this fashion, I easily can change the length of time required for the drum to move from Leak position to Off position.

As has been mentioned earlier herein, it is within the scope of my invention to rotate the drum between Off and On positions, and to lPreparation and Lapsed Time positions, by any suitable mechanism, a reciprocating handle having been shown herein as one of the embodiments of my invention. Likewise, I may, if desired, employ the switch 20 with a modified means 26, or without ythe means 26, or with a substitute type of means 24.

I have shown one substitute means 24 in FIGS. l3l7. It is of a simpler and sturdier construction and requires less parts than the means 24; however, it needs a different equipment for its manufacture and therefore may not be preferred by some companies. 'The switch mechanism 24' comprises athollow chamber 150in theinterior of the center post 59.72 (Where parte of theswiteh mechanism 24' are similar to parts of the

switch mechanism

2,4 they have been identified by the same numerals which, however, have been primed for differentiation) and symmetrically disposed about the axis of revolution of the drum 82.

171 An imbedded plug insert 104' which receives the needlebearing tip 106 of an electrically conductive shaft 108' is connected to an electrically conductive metal nger 152 that protrudes inside the chamber 150 from the rear wall thereof. Said nger is eccentrically disposed with respect to the axis of rotation of the drum 82', as is quite clear from inspection of FIGS. 13-17. The front end of the chamber 150 has flat against the same an electrically conductive metal plate 154 which is in electric contact with an electrically conductive imbedded plug insert 156 at the front face of the drum. The insert 156 is formed with a conical seat to receive the needle tip 158 of an electrically conductive shaft 160, so that the drum is rotatable between the two shafts 108', 160. Said two shafts are connected to electric terminals (not shown) for the switch mechanism 24.

Also located within the chamber is a pool 162 of an electrically conductive liquid, .e. mercury, the pool filling about one-half the volume of the chamber. It will be apparent that as the drum rotates, theV pool will be in continual contact with the plate 154, but in intermittent contact with the nger 152, and that the immersion of the finger 152 Within the pool or lifting thereof above the pool will depend Vupon the angular position of the drum, which accordingly will open or close the switch mecha- 4nism 24. FIGS. 14, 15, 16 and 17 respectively show the locations of the finger 152 in the Ofi On, Preparation, and Leak positions of the drum 82. In FIGS. 18-20 I have shown a switch 20 (parts of the switch 20" similar to parts of the switch 20'have been denoted by the same reference numerals, but doubleprimed for differentiation) which is the same as the switch 20 except for change in the means 26 for varying the lapsed time period and for abruptly terminating the same. Accordingly only so much of the switch 20 has been shown as is necessary to understand the modification.

The means 26" includes two

magnetic discs

136, 138 which have not been illustrated because they do not differ from the like discs of the means 26. However the spindle 140" (not shown) to which the disc 138 is fast is non-rotatable in the protuberance 36". Therefore the means 26 will abruptly terminate movement of the drum 82" to Off position from Leak position; but it does not include an adjustment for varying the lapsed time period. Instead I have provided a more easily settable arrangement for varying said period.

More particularly that part of the means 26" which varys the lapsed time period includes a cam follower 164 on the upper surface ofthe tab and a timing cam 166. The timing cam s in the form of a ring which is rotatable on the circular periphery of the lid 34 and is disposed in front of an escutcheon plate 168. The cam is captively but rotatably held to the lid by a pair of diametrically opposed pins 170 extending from the lid and received in limited length circumferential slots 172 in the ring. The front edge of the ring is shaped to provide acam surface 174 of progressively greater axial length over an arc equal to half the arc of the slots 172. For the sake of appearance two oppositely extending cam surfaces are included.

By manually shifting the position of the timing cam any selected portion of either cam surface can be brought into alignment with the path travel of the cam follower 164. In this manner I can selectively vary the position of the tab 40., and therefore of the drum 82, in Leak position.

When the timing cam is so positioned that the follower strikes the meeting point of the two cam surfaces 174 in the Leak position of the handle 38, the drum 82 will be swung so far that all the liquid 84 will spill over the divisive flange 94 and the drum, accordingly, will rotate to Oli position. Thus there will be no time delay.

In any other position of the timing cam the cam follower will strike a cam surface at an earlier point in the 'upward movement of the rhandle which will varyngly I2 correspond to drum'positions prior to' spill over'or various" angular positions of partial spill over. Obviously the further up the handle rocks, the closer will the set Leak position of the drum be to complete spill over position and the less will be the time before the drum starts to turn by itself. Therefore the lapsed time period will be an inverse function of the extent of upward movement ofV the handle.

The lapsed time periods are indicated by numerals 176 and lines 178 on the front face of the escutchen plate which represent minutes of lapsed time and are to be read against a marker constituting the meeting of the two cam surfaces 174.

It thus will be seen that I have provided devices which achieve the various objects of my invention and are well adapted to meet the conditions of practical use.

As various possible embodiments might be made of my invention and as various changes might be made in the embodiments above set forth, it is to be `understood that all matter herein described, or shown in the accompany-y ing drawings, is to be interpreted as illustrative and not in a limiting sense. v

Having thus described my invention, I claim as new and desire to secure by Letters Patent: v

1. A lapsed timer comprising a hollow drum having a central axis, means dividing the drum into two eccentric sectional compartments, means providing a large passageway over said dividing means between said two compartments, means providing a passageway below at least part of said dividing means and extending between said two compartments, said passageway having a restricted opening therein, a liquid within said drum, means mounting said drum for oscillation about said central axis and means preventing said drum from rotating when said drum is in unstable equilibrium with the liquid in one of the compartments which then is uppermost and permitting the drum to turn when suicient liquid has flowed through the second passageway into the other compartment to change the equilibrium of the v drum to an opposite unstable equilibrium.

2. A lapsed timer as set forth in claim 1 which further includes means for varying the period of time required to change the equilibrium of the drum to the opposite unstable equilibrium.

3. A lapsed timer as set forth in claim l which further includes means to rapidly shift the equilibrium of the drum to the opposite unstable equilibrium after the equilibrium of the drum has started to change to such opposite unstable equilibrium.

4. A lapsed timer as set forth in claim 1 which further includes magnetic means to rapidly shift the equilibrium of the drum to the opposite unstable equilibrium after the equilibrium of the drum has started to change to such opposite unstable equilibrium.

5. A lapsed timer as set forth in claim 1 which further includes registerable magnetic means on the drum and on the mounting means for the drum to rapidly shift the equilibrium of the drum to the opposite unstable equilibrium after the equilibrium of the drum has started to change to such opposite unstable equilibrium. r

6. A lapsed timer as set forth in claim 1 which further includes means to vary the time required to change the equilibrium of the drum to the opposite unstable equilibrium and means to rapidly shift the equilibrium of the drum to the opposite unstable equilibrium after the equilibrium of the drum has started to change to such opposite unstable equilibrium. A

7. A lapsed timer comprising a container providing a chamber, means dividing the chamber into two eccentric compartments, means providing a large passageway over said dividing means between said two compartments, means providing a passageway below at least part of said dividing means and extending between said two compartments, said second passageway having a restricted opening therein, a liquid within said chamber, means mounting said container for angular movement, said container when in one angular position being supported in unstable equilibrium with the liquid principally in one of the compartments which then is uppermost so asl to permit the liquid to flow through the second passageway into the other compartment, said supporting means permitting the container to swing when, after a lapsed time, the equilibrium of the container will be shifted to an opposite unstable equilibrium, and means to abruptly terminate the lapsed period of time, said last named means including a permanent magnet operationally integral vwiththe container, and a permanent magnet independent of the container and adjacent the first permanent magnet, said magnets being so arranged that as the container moves toward the position of opposite unstable equilibrium, the magnets are shifted toward relative positions in -which their unlike poles are juxtaposed.

8. A lapsed timer comprising a container providing a chamber, means dividing the chamber into two eccentric compartments, means providing a large passageway over said dividing means between said two compartments, means providing a passageway below at least part of said dividing means and extending between said two compartments, said second passageway having a restricted opening therein, a liquid within said chamber, means mounting said container for angular movement, said container when in one angular position being supported in unstable equilibrium with the liquid principally in one of the compartments which then is uppermost so as to permit the liquid to flow through the second passageway into the other compartment, said supporting means permitting the container to swing when, after a lapsed time, the equilibrium of the container will be shifted to an opposite unstable equilibrium, and means to vary and to abruptly terminate the lapsed period of time, said last named means including a permanent magnet operationally integral with the container, a permanent magnet independent of the container and adjacent the first permanent magnet and means to vary the relative orientations of said magnets independent of the movement of the container, said magnets being so arranged that as the container moves toward the position of opposite unstable equilibrium, the magnets are shifted toward relative positions in which their unlike poles are juxtaposed.

9. A lapsed timer comprising a hollow drum having a central axis, means dividing the drum into two eccentric sectional compartments, means providing a large passageway over said dividing means between said two compartments, means providing a passageway below at least part of said dividing means and extending between said two compartments, said passageway having a restricted opening therein, a liquid within said drum, means mounting said drum for oscillation about said central axis from a first angular position to a second angular position and back to a third angular position short of said first angular position, the liquid being located in one of said compartments which is lowermost when the drum is in the first angular position and owing through the large passageway to the other compartment which is uppermost when the drum is moved from the first to the second and then to the third angular position whereby the liquid thereupon will fiow from said other compartment to said one compartment throughv the restricted opening when the drum is in the third angular position, said drum being in unstable equilibrium when the liquid is in said other compartment in the third angular position and being in reverse unstable equilibrium after flow of liquid through the restricted opening for a lapsed period of time, manually manipulatable means for moving said drum from said first to said second and then back to said third position, and means to hold said drum in said third angular position when the liquid is in said other compartment and to permit the drum to rotate back to the first angular position when the liquid flow has placed said drum in said reverse unstable equilibrium.

10. A lapsed timer as set forth in claim 9 wherein manually controllable means is provided to vary the third angular position whereby to vary the lapsed period of time required to change the drum from unstable equilibrium to lreverse unstable equilibrium.

11. A lapsed timer comprising a hollow drum', means dividing the drum into two eccentric compartments, said dividing means extending from an internal wall of the drum toward but spaced from an opposite wall of the drum .to `provide a large passageway over said dividing means which passageway connects said two compartments, means providing a restricted passageway adjacent the base of the dividing means which restricted passageway connects said two compartments, a liquid within said chamber, a casing, said drum being located within said casing, cooperating means at one end of said drum and the associated end of the casing mounting said drum for rotation within said casing, cooperating means on the other end of said drum and associated end of the casing coaxially mounting said drum for rotation within said casing, a positioning disc within said casing, means mounting said disc for rotation within said casing about an axis coincident with the axis of rotation of the drum, cooperating means on the drum and positioning disc for oscillating the drum upon oscillation of the positioning disc, said cooperating means including a lost motion connection, a gear operationally integral with said positioning disc, a second gear meshing with said first gear, means mounting said second gear on said casing for rotation relative thereto, a manually operable handle operationally integral with said second gear for selectively setting this angular position of the positioning disc, a permanent magnet carried by the drum, a second permanent magnet carried by the casing and adjacent the permanent magnet carried by the drum, means for varying the relative angular position of said permanent magnets while the drum is stationary, a third permanent magnet carried by the drum, a fourth permanent magnet, means mounting the fourth permanent magnet on the casing adjacent the third permanent magnet, said mounting means restraining the third permanent magnet against rotation about the axis of rotation of the drum, and permitting movement of the fourth permanent magnet toward and away from the drum, and an electric switch operated by movement of the fourth permanent magnet.

12. A lapsed timer comprising a hollow drum, means dividing the drum into two eccentric compartments, said dividing means extending from an internal wall of the drum toward but spaced from an opposite wall of the drum to provide a large passageway over said dividing means which passageway connects said two compartments, means providing a restricted passageway adjacent the base of the dividing means which restricted passageway connects said two compartments, a liquid within said chamber, a casing, said drum being located within said casing, cooperating means at one end of said drum and the associated end of the casing mounting said drum for rotation within said casing, cooperating means on the other end of' said drum and associated end of the casing coaxially mounting said drum for rotation within said casing, a positioning disc within said casing, means mounting said disc for rotation within said casing about an axis coincident with the axis of rotation of the drum, cooperating means of the drum and positioning disc for oscillating the drum upon oscillation of the positioning disc, said cooperating means including a lost motion connection, a gear operationally integral with said positioning disc, a second gear meshing with said rst gear, means mounting said second gear on said casing for rotation relative thereto, a manually operable handle operationally integral with said secondgear for selectively setting this angular position of the positioning disc, a permanent magnet carried by the drum, a second permanent magnet carried by the casing and adjacent the permanent magnet carried by the drum, means for varying the relative angular position of 15Kv l said permanent magnets while `the drum ,is stationary, means providing a second chamber operationally integral with .the drum, a body of conductive liquid within and partially filling the second chamber, an electrically conductive member within and contacting said body of liquid in all functionally operative positions of the drum, and a second electrically conductive member operationally integral with the drum and eccentricallyv disposed with respect to the axis of rotation thereof, and locatedy to, conwww drum, and to be .out of contactwith the body of electrically conductive liquid in other angular positions olf the drum.

References Cited in the le of this patent UNITED STATES PATENTS Australiav Jan. 26, 1

Claims

1. A LAPSED TIMER COMPRISING A HOLLOW DRUM HAVING A CENTRAL AXIS, MEANS DIVIDING THE DRUM INTO TWO ECCENTRIC SECTIONAL COMPARTMENTS, MEANS PROVIDING A LARGE PASSAGEWAY OVER SAID DIVIDING MEANS BETWEEN SAID TWO COMPARTMENTS, MEANS PROVIDING A PASSAGEWAY BELOW AT LEAST PART OF SAID DIVIDING MEANS AND EXTENDING BETWEEN SAID TWO COMPARTMENTS, SAID PASSAGEWAY HAVING A RESTRICTED OPENING THEREIN, A LIQUID WITHIN SAID DRUM, MEANS MOUNTING SAID DRUM FOR OSCILLATION ABOUT SAID CENTRAL AXIS AND MEANS PREVENTING SAID DRUM FROM ROTATING WHEN SAID DRUM IS IN UNSTABLE EQUILIBRIUM WITH THE LIQUID IN ONE OF THE COMPARTMENTS WHICH THEN IS UPPERMOST AND PERMITTING THE DRUM TO TURN WHEN SUFFICIENT LIQUID HAS FLOWED THROUGH THE SECOND PASSAGEWAY INTO THE OTHER COMPARTMENT TO CHANGE THE EQUILIBRIUM OF THE DRUM TO AN OPPOSITE UNSTABLE EQUILIBRIUM.