US2789168A - Switch assembly for timers - Google Patents

Description

p l 16, 1957 1.. J. LAVIANA 2,789,168

' swnca ASSEMBLY FOR 'rxlmas Filed Feb. 15, 1955 FIG.I

. INVENTOR- L A WPENCE. a. LA V/A NA ATTORNEYS United States Patent SWITCH ASSEMBLY FOR TIMERS Lawrence J. Laviana, Kensington, Conn., assignor to M. H. Rhodes, Inc., Hartford, Conn., a corporation of Delaware Application February 15, 1955, Serial No. 488,293

Claims. (Cl. 200-35) This invention relates to timers of the type having a timing mechanism and an electrical switching mechanism controlled thereby. More particularly, the invention relates to improvements in the switching mechanism of such timers.

Timers of this type are widely used in the electrical appliance field and elsewhere to provide a convenient and effective means for controlling a variety of electrical switching operations at preselected times. The particular switching operation to be controlled dictates the type of switch required in the timer, i. e. singleor doublepole, singleor double-throw, etc., as well as the manner of operation of the switch. To meet the switching requirements of various installations, it has heretofore been the practice of manufacturers of such timers to make a variety of models, each with its own switching mechanism especially tailored for a particular installation. This procedure has several disadvantages, however, among which are the limited length of production run possible when making any one model, the excessive number of different parts involved and attendant large inventories required, and the difiiculty of adapting any one model for use in installations other than those for which it was originally planned.

The principal object of the present invention is to re- :duce the number of different parts as well as the cost of manufacture of a line of such timers having different switching mechanisms each adapted for use in a particular installation.

Another object is to provide a timer of the character described having an improved switching mechanism can .able of switching any desired number of circuits in any desired manner.

Another object is to provide in such timers a switching mechanism of improved flexibility which can be eas- 'ily tailored for us in a particular control circuit, yet may be readily converted for use in a different circuit.

Other objects will be in part obvious and in part pointed :out more in detail hereinafter.

The invention accordingly consists in the features of construction, combination of elements and arrangement of parts which will be exemplified in the construction hereafter set forth and the scope of the application of which will be indicated in the appended claims.

In the drawing: Figure l is an elevation view partly in section of a timer constructed in accordance with the present inven- 'tion;

Figure 2 is a plan view of one component of the switching mechanism of the timer shown in Figure 1;

Figure 3 is a bottom View of the timing mechanism of the timer shown in Figure 1 taken approximately on cordance with the present invention includes a timing ice mechanism designated generally at 2 and a switching mechanism designated generally at 4.

The timing mechanism includes a spring-driven clockworks supported in a frame including a lower plate 6. The frame is enclosed within a casing 8. On the top of the casing is an externally threaded sleeve 12, and in the timer shown a cup-shaped signal bell 14 is mounted on the sleeve and surrounds the casing 8.

The main shaft 10 of the clockworks projects from the top of the casing through sleeve 12 and is adapted to carry a knob by which the shaft may be turned to wind the clock spring. The lower end of the shaft 10 is journaled in plate 6 and carries a control cam 16. A peripheral notch 18 in the cam 16 has a radial trailing side and a sloping leading side formed with one or more steps 26. Adjacent cam 16 is a disc 22 of slightly larger diameter journaled on the shaft 10 and also provided with a peripheral notch 24. Except that its leading side is radial rather than sloping, notch 24 corresponds in shape with notch 18, having one or more steps 25. The disc 22 and cam 16 are connected to permit limited lost motion by a pin 26 on the cam which engages a slot 28 in the disc. A lever 35%, pivotally mounted on plate 6 by a pin 32, is biased toward the cam 16 and disc 22 by a spring 34 connected between its free end and an anchor on the plate 6. A follower 36 on the lever rides on the periphery of the disc 22. With this arrangement when the shaft it) is turned so that the notches 18, 24 and the follower 36 are aligned, the follower falls into the notches 13, 24, thereby producing limited angular movement of the lever St. A switch actuating member in the form of a longitudinal pin or arm 52 is mounted on the free end of lever 3% parallel to shaft 10.

In accordance with the invention, the switching mechanism of the timer is made up of a plurality of individual components or sections each containing a complete switch of a particular type. The individual sections are substantially identical except for the particular switch contained in each, and hence any desired number of sections having a desired variety of switches may be grouped together to form a complete switch mechanism of composite construction capable of meeting the switching requirements of any particular installation. Two different exemplary switch sections are shown in Figures 2 and 4, that in Figure 4 having a double-pole single-throw switch and that in Figure 2 having a double-pole single-throw switch arranged for sequential operation of its two poles. Each section is completely self-contained and includes a shallow cup-shaped body portion or housing 40 of nonconducting material having a flat bottom wall 42 and a cylindrical peripheral wall 44. The bottom wall 42 has a section of diminished thickness which may be knocked out to form a slot 43. The top edge of the peripheral wall is formed with notches 46 and a rabbet 48, and the outside of the bottom wall has an annular ridge 50. Rising from the bottom wall and terminating level with the top of the peripheral wall is a plurality of interior pillars or columns 52, each having a throughbore 54. Rotatably mounted at the center of the bottom wall of each section is a disc-type switch cam 56 of non-conducting material having one or more peripheral nose portions 58 and a crank portion having a short radial slot 60. Cooperating with the switch cam are the current conducting members of the switch, including one or more fixed contacts 64 each mounted on a post 66, and corresponding movable contacts 68 each carried by a flexible contact arm 70 mounted on a post 72. Each contact arm 76 is disposed for engagement by the switch cam 56 and for movement between make and break positions responsive to limited angular movement of the switch cam. The arms 70 are shown in their operating or on position in Figures 2 and 4. Depending on the relative positions as described, the operation of the timer is as follows.

having the relative positions shown in Figure 3.

of the contact arms 70 and earns 56, the arms may be arranged to move simultaneously or sequentially as cam 56 is rotated. Connected to the bottom ends of posts 66, 72 are radially extending terminal members 74.

' With the individual switch sections constructed as described, .a switch mechanism suitable for the requirements of a particular installation may be readily provided simply by assembling several individual housings containing the number and types of switches required. The several individual housings 40 are assembled in stacked relation with the pillars 52 of each abutting the bottom wail 42 of the one above and with the rabbet 48 of each receiving the ridge '50 of the one above for enhanced rigidity, and are secured to the timing mechanism by screws tit} which extend through the bores 54 in the pillars 52 and are threadably received in the plate 6. The bottom edge of easing 8 nests in the rabbet of the uppermost housing to .insure afirm and rigid connection between the timing mechanism and assembled housings so. The terminal members 74 of each housing project outwardly througr the notches 46 of the one below to facilitate convenient wiring of the individual switches. The longitudinal pin or arm 82 on the free end of the lever 30 extends down through the slot 60 in each cam, passing through the slot 43 in the bottom wall of'each housing except the lowermost.

With the switch mechanism constructed and arranged As the shaft 10 is turned counterclockwise as shown in Figure 3, cam 16 lifts the follower 36 up out of the notches 18, '24 and onto the periphery of the disc 22, the clock spring is wound, and the angle through which the shaft is turned determines the time interval which must elapse before the follower can again fall into the notch 24. The limited clockwise angular movement of the lever 30 which accompanies lifting of the follower out of the notches 18,

.24 likewise moves pin or arm -82 through a limited angle,

this movement being accommodated by the slots .13. This rotates all of the switch earns 56 in unison counterclockwiseto the positions shown in Figures 2 and 4, and .thereby moves the contact arms 70 in all the housings 4i tosetallof the switches at their respective operating positions, .as shown in Figures 2 and 4. The clock then drives the shaft 10 clockwiseas shown in Figure 3, the cam .lfipulling the'disc 22 and the cam 16 and disc 22 g After sutficient time has elapsed to align the follower 36 with the leading edge of the notch 24, the follower drops into .the.notch,.landing on its step 25. This moves arm 82 a corresponding amount counterclockwise as shown in Fig- .ure 3 :and causes all of the switch cams tobe rotated in unison, clockwiseas shownin Figures 2 and 4, through a -.predeterniined angle, thereby engaging tone or more nose portions 58 with arms 74 and producing a predetermined operation of the switch controlled by each cam.

:Rotation of the shaft it for additional periods of time,

depending in number and length on the number and length :of steps 25, causes arm 82 to rotate all of the switch cams 56 in unison through additional predeter- .mined angularincrements, .clockwiseas shown in Figures :2 and 4, thereby engaging the remaining cam nose portions.58, if any, andperforrning additional switching 0perationsasall of the arms 70 are returned in stepwise fashion to their original .non-operating'or off position.

An importantradvantage of the inve on is the fact that timers .having switching mechanisms constructed arranged as above -described can'be eificiently and n- :need :be manufactured for an entire line of timers, regard- ,lessr'of the many'different types ofswitches required for differenttimer -applications,-and since the individualxswitch sections are substantially identical except for the paiticul'ar type of switch contained therein, it will be appreciated that the invention substantially reduces the number of different parts required for a complete line, and thereby provides substantial economies both in inventory and manufacturing costs. Moreover, the construction described permits the assembly with a single timing mechanism of any desired number of switch sections capable of switching any desired number of circuits in any desired manner. Furthermore, since all the switch sections differ only in respect to the particular type of switch in each, and since each is completely self-contained and conveniently removable and interchangeable, a timer constructed in accordance with the invention is extremely flexible and may be readily converted from one use to another.

As many changes could be made in the above construction and many apparently widely different embodiments of this invention could be made without departing from the scope thereof, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

It is also to be understood that the language used in the following claims is intended to cover all of the generic and specific features of the invention herein described and all statements .of the scope of the invention which, as a matter of language, might be said to fall therebetween.

I claim:

1. In a timer, a timing mechanism, a switching mechanism formed of a plurality of removable and interchangeable switch-ing sections, each switching section comprising an open-ended cup-shaped housing including a bottom wall and a cylindrical peripheral wall having means to support another such section in stacked relation, means disposed within the housing adapted to receive fasteners for securing the section to other like sections, a switch cam rotatably mounted on said bottom wall and having a crank portion, fixed switch contacts in said housing, and cooperable movable switch contacts in said housing controlled by said switch cam, a movable actuator member controlled by the timing mechanism disposed for extension axially of each switching section for engagement with said crank portion formo'-/ement of the switch cam, and a knock-out in the bottom wall of each switching section registrable with the locus of movement of said actuator member.

2. In a timer having a timing mechanism and a switching mechanism, a switch section forming a constituent part of the switching mechanism comprising an openended cup-shaped housing including a hat bottom wall having an annular ridge on its underside and a cylindrical peripheral wall having a rabbeted upper edge for receiving the ridge of another such section to support such section in marginally telescoped stacked relation, pillars upstanding from said bottom wall dimensioned to abut the bottom of a superposed section and having t roughbores adapted to receive mounting screws for fastening the section to other like sections and to the bottom of thetim-ing mechanism, a switch cam rotatabiy mounted on said bottom wall and having a slotted crank portion adapted to receive an actuator controlled by the timing mechanism, jfixed switch contacts in said housing, portion of reduced thickness forming a knock-out in said bottom wall through which the actuator may extend to additional sections below, and cooper-"able movable switch contacts in said housing-controlled by said-switch 3. In-a timer having a casing, a clock mechanism in the casing, a timing cam driven in one direction by the clock mechanism and movable in the other direction to set the desired tirnecycle, and-a longitudinally extending arm controlled by the timing cam movable in a transverse direction between an operating position and an etf-pcsition, a switch --mechanism adapted to -be'coutrolled bv said clock mechanism comprising a plurality of removable and interchangeable open-ended cup-shaped switch housings mounted on the casing in longitudinally stacked coaxial relation, a switch cam in each of said switch housings rotatable about a longitudinal axis and having a transverse slot adapted to receive said arm, a knockout in the bottom of each housing forming an opening beneath the locus of movement of the cam slot therein through which said arm may extend, and a switch in each housing operatively associated with the switch cam therein.

4. In a timer, a timing mechanism having a cylindrical casing, a switching mechanism adapted to be controlled by the timing mechanism and comprising a plurality of constituent sections, each of said sections having a cupshaped housing including a flat bottom wall and a cylindrical peripheral wall having means for supporting a superposed section in stacked relation, means for securing said sections together and to said timing mechanism in stacked relation and with the sides of the sections forming a substantially uninterrupted continuation of the cylindrical shape of the timing mechanism casing, a rotatable switch cam mounted on the bottom wall of each housing having a slotted crank portion, fixed switch contacts in each housing, cooperative movable switch contacts controlled by said switch cam, means forming an opening in the bottom wall of each housing below the locus of movement of said crank portion, and an actuator controlled by the timing mechanism extending through said openings and through the crank portion of the switch cam in each housing.

5. In a timer, a timing mechanism, a switching mechanism adapted to be controlled by the timing mechanism and comprising a plurality of removable and replaceable constituent sections, each of said sections having a cup-shaped housing including a flat bottom wall and a cylindrical peripheral wall having means for supporting a superposed section in stacked relation and provided with notches at its upper edge, pillars upstanding from the bottom wall of each housing dimensioned to abut the bottom wall of the section above and having throughbores receiving mounting screws for securing said sections to said timing mechanism in stacked relation, a rotatable switch cam mounted on the bottom wall of each housing and having a slotted crank portion, fixed switch contacts in each housing, cooperative movable switch contacts controlled by said cam, terminal members on each housing connected to said contacts and projecting radially through the notches in the peripheral wall of the housing below, means including a knock-out portion forming an opening in the bottom wall of each housing below the locus of movement of said crank portion, and an actuator controlled by the timing mechanism extending through said openings and through the crank portion of the switch cam in each housing.

Jefirey July 29, 1952 Koenig Jan. 20, 1953

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