US3516244A - Front chassis assembly for time delay or interval timers - Google Patents

Description

" June 23, 1970 F, J, PAPA, JR 3,516,244

FRONT G HASS IS ASSEMBLY FOR TIME DELAY OR INTERVAL TIMERS Filed June 17, 1968 2 Sheets-Sheet 1 INVENTOR FRANK J. PAPA,JR.

ATTORNEY F. J. PAPA, JR

Jmie 23, 1970 2 Sheets-Sheet 2 Filed June 17, 1968 8 B7 J m w m "S m w 9v a L 6 a 1 E T; M w o 5 B F & a F 2 FRANK J. PAIPA,JR.,

ATTORNEY United States Patent 3,516,244 FRONT CHASSIS ASSEMBLY FOR TIME DELAY OR INTERVAL TIMERS Frank J. Papa, Jr., Montville, N.J., assignor to Industrial Timer Corporation, Parsippany, N.J., a corporation of Delaware Filed June 17, 1968, Ser. No. 737,495 Int. Cl. G04f 3/04, 3/08; G04b 37/00 U.S. Cl. 58-223 14 Claims ABSTRACT OF THE DISCLOSURE Front chassis assembly for a time delay or interval timer including a chassis plate having a bushing therein protruding from the front side of the plate, a dial mounted on the front side of the plate coacting with an indicator carried on an indicator shaft rotatably mounted in the bushing, a time period selector rotatably mounted on the bushing having a pointer portion and stop coacting with the timing pointer to set the timer, and a frictionally mounted knob adjusting assembly drivingly connected to the selector pointer to adjust its position on the dial.

This invention relates in general to timers, and more particularly to a front chassis assembly for a time delay or interval timer having an improved time setting mechanism, and still more particularly to a front chassis assembly for a time delay timer including a meter face that may be panel mounted where the time period may be knob adjustable.

The timer front chassis assembly of the present invention includes a zinc die cast chassis and plastic molded parts resulting in lower material costs and ease of assembly. The assembly may be panel mounted and presents a modern appearance with a meter face. An improved time setting mechanism includes a selector that enables precise selection of the time delay and coacts with the dial pointer. The selector is provided with a Vernier adjustment to enhance the preciseness of the time delay in choosing the delay. A frictional mounting for the selector assures holding of a selection after it has been made. Coaction between the timing pointer and the selector is such to assure that the actual time delay coincides exactly with the chosen time delay by the selector. A friction knob is provided with the selector to protect the time setting mechanism.

Accordingly, it is an object of the present invention to provide an improved timer front chassis assembly having an improved time setting mechanism.

Another object of this invention is in the provision of a timer front chassis assembly having a modern appearance with a meter face and capable of being panel mounted.

Still another object of this invention resides in the provision of a timer front chassis assembly that may be inexpensively made with a zinc die cast chassis and plastic parts.

Other objects, features and advantages of the invention will be apparent from the following detailed disclosure, taken in conjunction with the accompanying sheets of drawings, wherein like reference numerals refer to like parts, in which:

FIG. 1 is a front elevational View of the timer front chassis assembly of the present invention;

FIG. 2 is a side elevational view of the chassis assemy;

FIG. 3 is a rear elevational view of the chassis assembly;

FIG. 4 is a front elevational view of the chassis assembly with the shield and knob assembly removed to show underlying parts;

FIG. 5 is a rear elevational view, partially fragmentary, of the shield and knob assembly as removed from the chassis;

FIG. 6 is an exploded side elevational view of the chassis assembly of the present invention;

FIG. 7 is a vertical sectional view taken through the assembly;

FIG. 8 is an enlarged and fragmentary view of the pointer attaching hub and illustrating its mounted position on the indicator shaft with the retaining screw removed; and

FIG. 9 is an exploded side elevational view of the friction knob employed in the timer of the invention, and illustrating the knob partially in section for purposes of clarity.

Referring now to the drawings, the timer front chassis assembly of the present invention, generally indicated by the numeral 10, is shown in completely assembled relationship in FIGS. 1, 2 and 7, and is adapted to be employed with a suitable time-motion-transmitting mechanism. In general, the front chassis assembly include a chassis assembly or plate 11, a dial 12 secured to one side of the chassis plate 11, a transparent shield 13 covering the dial and secured to the chassis plate, a knob or timing ad justment assembly 14 mounted on the siheld 13, a pointer assembly 15 to be drivingly connected to a time-motiontransmitting mechanism, and a time cycle selector assembly 16.

The chassis plate 11 is Zinc die cast and includes a front side or face 17 and a back side or face 18. A pair of locating lugs 19 are provided on the front face 17 to coact with cutout portions 20 of the dial 12 locating the dial properly on the front face of the chassis plate. Drive screws 21 secure the dial to the chassis plate. The front face of the dial 12 is preferably white enameled with indicia 22 that includes black graduated markings and numerals thereon. The indicia is arcuately arranged along an arc of about A bushing 23 is suitably press fitted into an opening in the chassis plate 11 to define a sleeve bearing 24 for rotatably receiving an indicator shaft 25. A flange 26 is provided on the bushing to properly seat the bushing in the chassis plate. An external bearing surface or stub shaft 27 is provided on the bushing at the front face 17 of the chassis plate for rotatably mounting the selector 28 of the time cycle selector assembly 16 for coaction with the dial. Spacing and mounting studs 29 extend from the back face 18 of the chassis plate 11 to suitably mount the entire chassis assembly to a panel. An annular recess 30 is provided in the back face 18 for receiving a gasket to enable sealing relation between the timer housing sleeve and the chassis plate.

The indicator shaft 25 includes a radial flange 31 that bears against the rear end of the bushing 23 when mounted in the bushing as seen in FIG. 7, a forward portion 32 that is bearingly received in the bushing sleeve bearing 26, and a rear portion 33. At the very terminal end of the forward portion 32, the shaft is fiatted at 34 to define a male coupling portion matable with a female coupling portion in the form of an opening or socket provided in the hub 35 of the pointer 36 (FIG. 8). Thus, the pointer 36 of the pointer assembly 15 is locked onto the indicator shaft 25 for rotation therewith, and a retainer screw 37 operates to retain the pointer on the shaft.

Timing power is applied to the indicator shaft 25 through a quadrant adjustment 38 that is adjustably secured to the rear portion 33. The quadrant adjustment 38 is a molded plastic part with a metal insert 39 suitably threaded to receive one or more set screws 40 for adjustably locking the quadrant adjustment to the indicator shaft 25. The insert 39 is suitably press fitted or staked in the molded plastic portion of the quadrant adjustment. A segmental gear 41 is formed on the quadrant adjustment v38 for engagement with a pinion gear of the timing drive. A diametrically reduced portion 42 longitudinally split at 43 serves as a spool for a spiral spring 44 which has one end engaging in a slot 43 and the other end looped and attached to a lug 45 (FIG. 3) protruding from the back face 18 of the chassis plate 11. The spring is arranged to drive the indicator shaft and pointer 36 in a counterclockwise direction as shown in FIGS. 1 and 4. A spring retaining Washer 46 is fitted over the end of the indicator shaft rear portion 33 and held in place by an E-ring 47 which engages in a slot 48 formed on the indicator shaft.

The selector 28 includes a bore 49 bearingly received on the stub shaft 27, a pointer portion 50, a stop 51 for the pointer 36, and an internal gear segment 52. The selector 28 is molded of plastic, and held onto the bearing portion 27 by a self-locking retaining washer 53. A Mylar washer 54 is provided between the selector 28 and the washer 53. The selector 28 is spring loaded, in a counterclockwise direction as viewed in FIGS. 1 and 4, by a wire spring 55 bottomed at one end at the selector and at the other end on the chassis plate 11. The planar relationship between the pointer portion 50 of the selector 28 and the pointer 36 is such that when the pointer 36 abuts against the stop 51 it aligns with the pointer portion 50 in a plane normal to the dial. This assures that when the selector is adjusted to a particular time cycle, the pointer of the timer will start from that adjusted point. Following a time cycle of the timer, the spring 44 returns the pointer 36 to the home position of selector stop 51.

The knob or timing adjustment assembly 14 includes a molded plastic Vernier adjustment or shaft 56 having a threaded portion 57, a radial flange 58 at one end of the threaded portion, a diametrically reduced portion 59 at the other end of the threaded portion, a pinion gear portion 60 adjacent the flange 58, and a stub shaft 61 at the terminal end of the pinion gear 60. The pinion gear 60 meshes with the internal segmental gear 52 of the selector when the unit is assembled.

The Vernier adjustment or shaft 56 is frictionally and rotatably mounted on the transparent shield 13 at the lower central portion thereof, whereby the threaded portion 57 is bearingly received in a bore 62 formed in the front face of the shield. A washer 63 is first applied over the threaded portion 57 and against the flange 58 when assembling the Vernier adjustment with respect to the shield. Following the insertion of the shaft through the shield bore, a friction washer 64 sandwiched between plain washers 65 and 66 is applied over the threaded portion 57 at the outer surface of the shield. The shaft is frictionally mounted to the shield by applying a locking nut 67 onto the threaded portion 57 until the desired compression of the friction washer 64 is obtained, whereby the shaft will hold in any set position. A setscrew 68 is provided in the locking nut 67 to lock the locking nut in place. The frictional engagement is such that reset impact of the timer pointer 36 will not change the timing selection of selector 28. The spring 55 functions to take up any slack that might exist in the gear train and therefore act as an antibacklash between the gear segment 52 and the pinion gear 60. When in assembled relation, the stub shaft 61 is bearingly received in a recess 69 formed in the front face of the chassis plate 11 to properly support the knob shaft 56 and maintain the pinion gear in proper engagement with the segmental gear.

A knob assembly 70 is mounted on the diametrically reduced portion 59 of the Vernier adjustment or shaft 56 so that there is a friction coupling between the knob assembly 70 and the 'vernier adjustment to protect the time setting mechanism. As seen in FIG. 9, the knob assembly includes a molded plastic knob 71 having a blind bore 72 terminating in a bottom wall 73. The knob assembly also includes a plurality of friction Washers 74 sandwiched between opposed plain washers 75, wherein the plain washer engages against the bottom 73 of the knob 71. A bushing 76 bears against the outer plain washer within the bore 72 and is provided with a setscrew 77 alignable with a radial opening 77a in the knob and engageable with the diametrically reduced portion 59 of the Vernier adjustment to lock the bushing thereto. Another plain Washer 7 8 is provided on the outside of the bushing 76 and the parts are held in place within the bore 72 by an insert 79 that is suitably staked or otherwise secured in place within the bore 72. Thus, the bushing 76 is frictionally held or coupled to the knob 71, and when secured to the knob shaft 56 provides a friction coupling therewith.

The transparent shield 13 is molded butyrate and includes a front wall 80, a rearwardly extending peripheral wall 81 and a peripheral lip 82 on the wall 81. A gasket 83 is arranged between the shield and the chassis plate 11 to seal the unit and make it dustand oil-proof. An aluminum ring or band 84 having a forward lip 85 is applied over the shield and chassis plate periphery whereby the lip 85 engages against the shield lip 82. The rear edge 86 of the band 84 is rolled or spun over the rear face of the chassis plate to lock the band in place as well as lock the shield in sealed relationship with the chassis plate. Mounting the band 84 also aflixes in position the knob or timing adjustment assembly 14 so that the pinion gear 60 engages the internal segment gear 52 thereby drivingly connecting the knob assembly 70 with the selector 28. As seen particularly in FIGS. 1 and 5, the back side of the shield is painted black at 87 to conceal the working parts of the Vernier gear arrangement and present a more pleasing appearance.

In operation, setting of the timer is accomplished by turning of the knob assembly 70 in the direction to drive the selector to the calibrated position along the dial, thereby carrying the timing pointer 36 by virtue of its engagement with the selector stop. Thereafter, ener gization of the timer will cause the pointer to move towards zero to define the designated time delay. At the end of a time delay period, the pointer returns to the selector stop under the power of return spring 44. By virtue of the gear drive between the knob assembly 70 and the selector 28, a vernier movement is provided to enable accurate setting of the selector. At least as many teeth are provided on the internal segmental gear 52 as on the pinion gear 60. Preferably more teeth are provided on the segmental gear than on the pinion gear. For the illustrated embodiment, although not shown on the drawings, the pinion gear would have ten teeth and the segmental gear would have thirteenth teeth, whereby slightly more than one revolution of the shaft 56 is necessary to move the selector pointer through the about 90 arc of the indicia.

It will be understood that modifications and variations may be effected without departing from the scope of the novel concepts of the present invention.

The invention is hereby claimed as follows:

1. A front chassis assembly for a time delay timer comprising, a chassis plate having front and back sides, a bushing in said plate protruding from the front side, a dial mounted on the front side of said plate, an indicator shaft rotatably mounted in said bushing and extending from opposite sides of said plate, a pointer secured to said shaft at the front side of the plate and coacting with said dial, a selector rotatably mounted on said bushing at the front side of the plate having a pointer portion coacting with said dial to set the timer, an internal segmental gear portion and a stop portion for said pointer, a transparent shield mounted over the front side of the chassis, and a knob adjusting assembly frictionally and rotationally supported on said shield and having a spur gear for engagement with said selector gear portion to define a vernier timing adjustment.

2. A front chassis assembly as defined in claim 1, and a transparent shield over the dial and front side of the chassis plate enclosing said selector and pointer.

3. A front chassis assembly as defined in claim 1, means spring loading said selector.

4. A front chassis assembly as defined in claim 3, and means spring loading said pointer toward said selector stop portion.

5. A front chassis assembly as defined in claim 1, wherein said knob adjusting assembly includes a knob shaft having the spur gear on one end and a knob assembly on the other end.

6. A front chassis assembly as defined in claim 5, and said knob assembly including means frictionally connecting same to said knob shaft.

7. A front chassis assembly for a time delay timer comprising, a chassis plate having front and back sides, a bushing in said plate extending from the back side and protruding from the front side thereby defining a sleeve bearing through the plate and a stub shaft at the front side, a dial mounted on the front side of the plate having arcuately arranged indicia along about a 90 are, an indicator shaft rotatably mounted in said bushing sleeve bearing and extending from opposite sides of said bushing, a pointer secured to said indicator shaft at the front side of the plate and coacting with said dial, a timing cycle selector rotatably mounted on the bushing stub shaft at the front side of the plate, said selector including a pointer portion coacting with said dial, a stop portion for said pointer and a segmental internal gear, a transparent shield mounted on said chassis plate covering the front side thereof together with the dial, pointer and selector, and a selector drive shaft frictionally and rotationally mounted on said shield and having a pinion gear in engagement with said selector segmental gear, the gear ratio between the pinion gear and selector segmental gear defining a vernier movement between the selector drive shaft and selector, whereby about one revolution of the selector drive shaft will cause traversing of the selector pointer portion along substantially the entire dial indicia.

8. A front chassis assembly as defined in claim 7, wherein said selector segmental gear includes thirteen teeth and said pinion gear includes ten teeth.

9. A front chassis assembly as defined in claim 8, and a gear mounted on said indicator shaft at the back side of said chassis plate.

10. A front chassis assembly as defined in claim 9, and spring means driving said indicator shaft and pointer toward the selector stop portion.

11. A front chassis assembly as defined in claim 10, and means spring loading said selector.

12. A front chassis assembly as defined in claim 7, wherein said Selector segmental gear includes at least as many teeth as said pinion gear.

13. A front chassis assembly as defined in claim 7, wherein said selector segmental gear includes more teeth than said pinion gear.

14. A front chassis assembly for a time delay timer comprising, a chassis plate having front and back sides, a bushing in said plate protruding from the front side, a dial mounted on the front side of said plate, an indicator shaft rotatably mounted in said bushing and extending from opposite sides of said plate, a pointer secured to said shaft at the front side of the plate and coacting with said dial, a selector rotatably mounted on said bushing at the front side of the plate having a pointer portion coacting with said dial to set the timer, and a stop portion for said pointer, a transparent shield mounted over said front side of the chassis, a knob adjusting assembly supported on said shield and drivingly connected to said selector pointer portion to control movement thereof, said knob adjusting assembly including a knob shaft frictionally and rotatably mounted on said shield and extending from both sides thereof, means on the knob shaft for drivingly connecting to said selector, means on the knob shaft for mounting a knob thereon, and a knob mounted on said knob shaft having means for providing a frictional connection to said knob shaft.

References Cited UNITED STATES PATENTS 1,919,255 7/1933 Porter 58-22.9 1,919,256 7/1933 Porter 5822.9 2,163,419 6/1939 Warren 58-395 RICHARD B. WILKINSON, Primary Examiner J. F. GONZALES, Assistant Examiner U.S. Cl. X.R. 5839.5, 53

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