US3803923A

US3803923A - Fuel burner time control

Info

Publication number: US3803923A
Authority: US
Inventors: C Hajny
Original assignee: Johnson Service Co
Current assignee: Johnson Service Co; Johnson Controls International Inc
Priority date: 1972-05-22
Filing date: 1972-05-22
Publication date: 1974-04-16
Anticipated expiration: 1991-04-16
Also published as: CA992762A

Abstract

A timer control apparatus for selectively opening a valve or the like uses a conventional spring-wound clock drive mechanism slidably mounted in a housing so that its drive shaft is axially shiftable between two positions. A timer setting means is provided for turning the drive shaft to a selected time setting position and includes lost motion means to operatively engage the drive shaft only between minimum and maximum time setting positions. A time controlled lock means is provided for holding the drive shaft in either of the two axial positions and for freeing the drive shaft to be shifted to the other position upon rotation of the drive shaft to either the off position or maximum time setting position. A return spring urges the clock drive mechanism and associated drive shaft towards one of the two axial positions.

Description

I ajny States atet [191 FUEL BURNER TIME CONTROL Primary Examiner-Allan D. Herrmann Attorney, Agent, or FirmJohnson, Dienner, Emrich,

[75] Inventor: svlgisarles Emil l-lajny, Milwaukee, Verbeck & Wagner [73] Assignee: Johnson Service Company, [57 ABSTRACT Mlwaukee A timer control apparatus for selectively opening a [22] Fil d; M 22, 1972 valve or the like uses a conventional spring-wound clock drive mechanism slidably mounted in a housing [21] Appl' 25541s so that its drive shaft is axially shiftable between two positions. A timer setting means is provided for turn- 52 us. Cl. 74/35, l37/624.12 g the drive shaft to a Selected time Setting Position 51] Int. (:1. Fl6h 5/76, Fi6k 31/48 and includes lost motion means 10 operatively engage 58 Field oi Search 74/35, 3.52, 3.54; the drive shaft y between minimum and maximum 37 24 2 24,22, 2 ,12; 20 3 E time setting positions. A time controlled lock means is provided for holding the drive shaft in either of the [56] References Cit d two axial positions and for freeing the drive shaft to be UNITED shifted to the other pOSltiOl'l upon rotation Of the drive 3 388 602 6/1968 k 74/3 5 shaft to either the off position or maximum time set- 3SSO4S8 12/1970 33: 74/3'5 ting position. A return spring urges the clock drive p mechanism and associated drive shaft towards one of the two axial positions.

8 Claims, 10 Drawing Figures 412 e M J V 9 J4 ,/J00

96 92 I zuk 2 "s90 t 1. 33 J0 64! WUENTEflAPR is 1914 I SHEET 3 UF 3 40 J0 J6 J5 FUEL BURNER TIME CONTROL BACKGROUND OF THE INVENTION This invention relates to a time control apparatus, and in particular relates to a time control apparatus for selectively opening a valve or the like during a selected time period.

One object of this invention is to provide a time control apparatus having a means for preventing the timing mechanism to be set for less than a pre-determined minimum on time.

Another object of this invention is to provide a time controlled lock means for permitting the operation of the control element, such as a gas valve, only when the timer mechanism drive shaft is at particular angular orientations.

A still further object of this invention is to provide a time control apparatus for selectively operating a gas valve, wherein means are provided for'preventing the opening of the gas valve except in the full wind condition of the spring-wound clock drive mechanism and for preventing the closing of the gas valve until a selected time period elapses.

These and other objects will become clear upon the reading of the following description of the preferred embodiment and the appended claims.

SUMMARY OF THE INVENTION A timer control apparatus for operating a valve or the like uses a conventional timer mechanism which is assembled in a housing with the timer drive shaft axially shiftable between two positions. A timer setting means is provided for turning the drive shaft and includes a lost motion means to operatively engage the drive shaft only between a minimum timesetting position and a maximum time setting position. A time controlled lock means is provided for holding the driveshaft in either of the two axial positions and for freeing the drive shaft to be shifted to the other axial position upon rotation of the drive shaft to either the off position or maximum time setting position.

DESCRIPTION OF DRAWINGS For a better understanding of this invention, reference may be made to the accompanying drawings, in which:

FIG. '1 is a side elevational view depicting the preferred embodiment of this invention operatively coupled to a fuel burner valve assembly with its main gas valve shown in cross-section;

FIG. 2 is a side view taken from the left side of FIG.

FIG. 3 is a side view taken in the direction of the arrow 3-3 of FIG. 1 showing the dial face for the timer apparatus of this invention;

FIG. 4 is a partial view of the dial of FIG. 3 with the setting in the one hour position;

FIG. 5 is an exploded view of the various components in the preferred embodiment of this invention;

FIG. 6 is the dial used in the preferred embodiment of this invention; I

FIG. 7 is across-sectional view of the preferred embodiment of this invention;

FIG. 8 is a sectional view taken along the line 88 of FIG. 7 depicting the pair of lock discs when the time is in the off position; and

FIGS. 9 and 10 are similar to FIG. 8 showing the relative position of the pair of lock discs'when the timer is in the 4-hour and l-hour settings, respectively.

DESCRIPTION OF PREFERRED EMBODIMENT Referring to FIGS. 1 and 2, there is shown a fuel burner valve assembly generally designated by the reference numeral 10, having its gas valve 12 shown in cross-section in FIG. l. A time control apparatus, generally designated by the reference numeral 14 and embodying the principles of this invention, is mounted on valve assembly 10 and selectively opens and closes gas valve 12 to control the flow of gas through the gas valve assembly 12 between its inlet and

outlet ports

16 and 18, respectively.

As illustrated in FIGS. l and 7, a port 18 is formed within the valve assembly housing 18 adjacent to inlet port 16, and gas valve 12 is spring biased to seal off port 18. Gas valve 12 comprises a plug 20 having an annular flange 22, and an annular ring gasket 24 supported on the body portion 26 of the plug 20 and disposed forwardly in abutting relation with the annular flange 22 to provide a fluid-tight seal with port 18 under the force of spring 28.

Time control apparatus 14 comprises a timer mechanism 30 having a main drive shaft 32, a time setting means 34, and a timed controlled lock means 36.

The timer mechanism 30 could be any of a number of well-known, commercially available spring wind-up clock drive mechanisms, which drives timer drive shaft 32. The details of the timer mechanism 36 arenot described since they are well-known and do not form any part of this invention. The timer mechanism 30 is mounted in the bottom of a cupshaped container 40. The upper end of the cup-shaped container 40 is partially covered by end cap 42 which is frictionally mounted thereon.

A shaft extension 44 coupled to the end of timer drive shaft 32 slidingly mounts the timer mechanism 30 with respect to a time control housing 46. The time control housing 46 includes a cup portion 48 having cylindrical side walls 50 and a central aperture 52 formed in its bottom wall 54, and is preferably formed as a casting. A pin receiving opening 56 (FIG. 7) is formed in the upper surface of cup portion 48 for slidingly receiving a locating pin 58 mounted on the bottom wall of cup-shaped container 40 for the purposes of aligning the timer mechanism 30 relative to the timed control lock means 36 and to prevent rotation of the timer mechanism relative to housing 48.

The timed controlled lock means 36 is carried on shaft extension 44 and located within a central cavity 60 formed inwardly of the bottom surface of housing 48. The purpose of the timed controlled lock means 36 is to prevent the accidental closing of the gas valve 12 throughout the selected timed cycle. The time controlled lock means (FIG. 5) comprises a key 62 fixedly mounted on shaft extension 44, a pair of

lock discs

64 and 66, a torsion spring 68 having its ends connected between the lock disc for urging them to rotate in opposite directions, and a circular cover 70 for holding the time controlled lock means 36 within cavity 60. The

lock discs

64 and 66 have, respectively, stop

lugs

72 and 74 extending from their outer peripheries. These

stop lugs

72 and 74 are adapted to engage a stop block 76 projecting radially inwardly in cavity 60 (FIG.

One end 77 of torsion spring is hooked through opening 79 in look disc 64 (FIG. 5) and the other end 81 is hooked over a slanted slot (not shown) formed in the hub 85 of lock disc 66. Torsion spring 68 biases the two lock discs to rotate in opposite directions until their respective stop lugs engage the stop block 76 as depicted in FIG. 8. Each of the

lock discs

64 and 66 also are provided with centrally located

key ways

78 and 80, respectively, which are formed at an angular orientation with respect to their respective stop lugs so that they are in alignment whenever both stop lugs are brought together on the same side of the stop block 76. It is only when these two key holes are in alignment that it is possible to axially shift the timer drive shaft 32 and associated shaft extension 44 to either open or close valve 12.

To prevent any fluid from passing through central opening 52 in housing 48, an O-ring 91 on shaft extension 42 fits snugly in the annular shoulder 93 (FIG. 7) and is contained by retainer washer 95.

The time setting means 34 is coupled on the outer shank portion 86 of the timer mechanism which extends outwardly through the center aperture 88 in end cap 42 to permit the time control apparatus to be set for a prescribed minimum time period. The time setting means includes a lost motion means in the form of a disc 90 fixedly secured on shank 86 and having an arcuate cutout portion 92, and a time setting knob 94 with a drive lug 96 on its rearmost face which fits within the arcuate cutout segment 92 when the knob 94 is rotatably secured to the end of shank 86 by means of screw 98 (FIG. 7). In the embodiment shown in the drawings, the time control apparatus 14 operates on a minimum time of one hour and a maximum time of 4 hoursv Thus the length of the arcuate segment 92 is approximately 90 to permit the drive lug 96 to move through a one hour time space interval before operatively coupling with timer mechanism 30.

A representative time dial is illustrated in FIG. 6 and designated by the reference numeral 100. Dial 100 is also fixedly mounted on the shank 86 and the digits thereon sequentially are exposed through a window 102 provided in the front face 104 of end cap 42 as illustrated in FIG. 3. T line up the end cap 42 in proper relation to the dial 100, indexing means in the form of a narrow groove 106 (FIG. in cup member 40 and downwardly projecting dimple 108 in end cap 42 fit together when the end cap is press fitted onto the cup container 40.

As depicted in FIG. 3, the front face of the end cap 42 has instructions for setting the time control apparatus 14. The first step is to turn the time setting knob 94 until the numeral 4 appears in window 102. Upon this occurrence, the drive lug 96 (shown in phantom in FIG. 3) on the rear face of time setting knob 94 will engage the downwardly extending stop finger 110 on the end cap 42 preventing any further turning of the knob. Throughout this initial setting step, return spring 112 (FIG. 7) disposed between the cup portion 50 and the cup-shaped container 40 pushes outwardly on the timer mechanism 30 and associated drive shaft 32 and extension shaft 44 causing the key 62 to be disposed within keyway 78 of innermost lock disc 64. Referring to FIG. 8, the position of lock disc 64 in the off position is indicated by the solid line position of lug 72. The turning of the timer setting knob 94 to the 4-hour" position rotates the innermost lock disc 64 counterclockwise to the dotted position of lug 72 in FIG. 9 to permit the respective key ways 78 and to line up.

The second step as described, on the front face 104 (FIG. 3), is to "push in on the time setting knob 94. This action causes the entire timer mechanism 30 and its drive shaft 32 and associated shafts extension shaft 44 to move into the time control housing 46. The outer end 116 of shaft extension 44 which is seated in the U- shaped recess 118 of valve 20 pushes the valve 20 to the open position of FIG. 7. In this open position, the key 62 is completely within the key way 80 of lock disc 66 with the result that the innermost lock disc 64 is free to rotate. Under the spring action of torsion spring 68, lock disc 64 turns clockwise as viewed in FIG. 9 to the solid line position where it engages the stop block 76. Since the two key ways are now out of alignment, the key 62 cannot return to the off position and consequently the valve 12 is held in the open position.

The third step is to select the desired time period by turning the time setting knob 94 to the desired time. It is noted due to the lost motion means previously described, the minimum time which can now be set is 1 hour. When the time period has elapsed, the outermost lock disc 66 will have been driven counterclockwise as viewed in FIGS. 8 through 10 until it reaches stop block 76 and at this position the two key ways will again be in alignment permitting return spring 112 to push the timer mechanism 30 and shafts 32 and 34 outwardly to the off position. This axial shift of key 62 frees outermost lock disc 66 and by means of torsion spring 68, rotates the outermost lock disc with lug 74 counterclockwise to the position of FIG. 8. Thus, it is again impossible for the valve 12 to be opened.

I claim:

1. A timer control apparatus having a timer mechanism mounted in a housing such that its drive shaft is axially shiftable between first and second axial positions for operatively moving a valve or the like, comprising time setting means for turning said drive shaft to a selected time setting position and time controlled lock means for holding said drive shaft in either of said first or second axial positions and for freeing said drive shaft to be axially shifted to its other axial position upon rotation of said drive shaft to either the off position or the maximum time setting position said time setting means including a time setting knob rotatably supported on the outer end of said drive shaft, and lost motion means for operatively connecting said knob to said drive 'shaft to turn said drive shaft after said knob rotates a selected arcuate distance to provide a minimum time setting position.

2. The combination of claim 1, wherein said lost motion means comprises a circular disc fixedly secured on said drive shaft and having an arcuate cutout portion of a length equal to said arcuate distance, and said time setting knob includes a drive lug extending into said arcuate cutout portion.

3. A timer control apparatus having a timer mechanism mounted in a housing such that its drive shaft is axially shiftable between first and second axial positions for operatively moving a valve or the like, comprising time-setting means for turning said drive shaft to a selected time setting position and time controlled lock means for holding said drive shaft in either of said first or second axial positions and for freeing said drive shaft to be axially shifted to its other axial position upon rotation of said drive shaft to either the off position or the maximum time setting position wherein said time controlled lock means comprises a pair of lock discs rotatably mounted on said drive shaft, a key fixedly mounted on said drive shaft, each of said lock discs having a central key way shaped to receive said key and stop lug extending outwardly from its outer periphery, a stop block supported by said housing and disposed in the path of said stop lugs, and a torsion spring connected between said lock discs under tension for urging said lock discs to rotate in opposite directions, said key ways being in alignment whenever said stop lugs are brought together on the same side of said stop block and said key being free to move between said key ways upon said drive shaft turning to either said off position or said maximum time setting position.

4. A timer control apparatus having a time mechanism mounted in a cup-shaped container with its drive shaft extending axially through the closed and open ends and axially shiftable between first and second positions, comprising a'housing having a cup-shaped portion larger than said cup-shaped container and a cen* tral opening, said drive shaft slidably inserted through said central opening, means to hold said cup-shaped container in a non-rotational relation with said cupshaped portion, time setting means for turning said drive shaft to a selected time setting position, a cavity formed in said housing symmetrically of said central opening, and time controlled lock means disposed within said cavity for holding said drive shaft in either of said axial positions and for freeing said drive shaft to be axially shifted to its other position upon rotation of said drive shaft to either the off position or the maximum time setting position.

5. The com bination of claim 4, wherein said time setting means comprises an end cap secured across the open end of said cup-shaped container having a central aperture and a window in its end wall, a circular dial fixedly carried on said drive shaft adjacent said end wall with printed indicia disposed in a circular path in alignment with said window, a time setting knob rotatably supported on the outer end of said drive shaft forwardly of said end wall and lost motion means for operatively connecting said knob to turn said drive shaft after said knob rotates a selected arcuate distance to provide a minimum time setting position.

6. The combination of claim 5, wherein said lost motion means comprises a circular disc fixedly secured on said drive shaft and having an arcuate cutout portion of a length equal to said arcuate distance, and said time setting knob includes a drive lug extending into said arcuate cutout portion.

7. A timer control apparatus as defined in claim A, further comprising return spring disposed between the bottom of said cup-shaped container and the bottom of said cup-shaped portion of said housing for urging said timer mechanism and associated drive shaft outwardly of said cup-shaped portion of said housing 8. A timer control apparatus as defined in claim 7, wherein said time controlled lock means comprises a pair of lock discs rotatably mounted on said drive shaft, a key fixedly mounted on said drive shaft, each of said lock discs having a central key way shaped to receive said key and a stop lug extending outwardly from its outer periphery, a stop block supported by said housing and disposed in the path of said stop lugs, and a torsion spring connected between said lock discs under tension for urging said lock discs to rotate in opposite directions, said key ways being in alignment whenever said stop lugs are brought together on the same side of said stop block, said alignment of said key ways occurring whenever said drive shaft is in either said off position or said maximum time setting position, and said key moving from the key way of the outermost lock disc into the key way of the innermost lock disc upon said drive shaft reaching said off position.

Claims

1. A timer control apparatus having a timer mechanism mounted in a housing such that its drive shaft is axially shiftable between first and second axial positions for operatively moving a valve or the like, comprising time setting means for turning said drive shaft to a selected time setting position and time controlled lock means for holding said drive shaft in either of said first or second axial positions and for freeing said drive shaft to be axially shifted to its other axial position upon rotation of said drive shaft to either the off position or the maximum time setting position said time setting means including a time setting knob rotatably supported on the outer end of said drive shaft, and lost motion means for operatively connecting said knob to said drive shaft to turn said drive shaft after said knob rotates a selected arcuate distance to provide a minimum time setting position.

3. A timer control apparatus having a timer mechanism mounted in a housing such that its drive shaft is axially shiftable between first and second axial positions for operatively moving a valve or the like, comprising time setting means for turning said drive shaft to a selected time setting position and time controlled lock means for holding said drive shaft in either of said first or second axial positions and for freeing said drive shaft to be axially shifted to its other axial position upon rotation of said drive shaft to either the off position or the maximum time setting position wherein said time controlled lock means comprises a pair of lock discs rotatably mounted on said drive shaft, a key fixedly mounted on said drive shaft, each of said lock discs having a central key way shaped to receive said key and stop lug extending outwardly from its outer periphery, a stop block supported by said housing and disposed in the path of said stop lugs, and a torsion spring connected between said lock discs under tension for urging said lock discs to rotate in opposite directions, said key ways being in alignment whenever said stop lugs are brought together on the same side of said stop block and said key being free to move between said key ways upon said drive shaft turning to either said off position or said maximum time setting position.

4. A timer control apparatus having a time mechanism mounted in a cup-shaped container with its drive shaft extending axially through the closed and open ends and axially shiftable between first and second positions, comprising a housing having a cup-shaped portion larger than said cup-shaped container and a central opening, said drive shaft slidably inserted through said central opening, means to hold said cup-shaped container in a nOn-rotational relation with said cup-shaped portion, time setting means for turning said drive shaft to a selected time setting position, a cavity formed in said housing symmetrically of said central opening, and time controlled lock means disposed within said cavity for holding said drive shaft in either of said axial positions and for freeing said drive shaft to be axially shifted to its other position upon rotation of said drive shaft to either the off position or the maximum time setting position.

5. The combination of claim 4, wherein said time setting means comprises an end cap secured across the open end of said cup-shaped container having a central aperture and a window in its end wall, a circular dial fixedly carried on said drive shaft adjacent said end wall with printed indicia disposed in a circular path in alignment with said window, a time setting knob rotatably supported on the outer end of said drive shaft forwardly of said end wall and lost motion means for operatively connecting said knob to turn said drive shaft after said knob rotates a selected arcuate distance to provide a minimum time setting position.

7. A timer control apparatus as defined in claim 4, further comprising return spring disposed between the bottom of said cup-shaped container and the bottom of said cup-shaped portion of said housing for urging said timer mechanism and associated drive shaft outwardly of said cup-shaped portion of said housing.

8. A timer control apparatus as defined in claim 7, wherein said time controlled lock means comprises a pair of lock discs rotatably mounted on said drive shaft, a key fixedly mounted on said drive shaft, each of said lock discs having a central key way shaped to receive said key and a stop lug extending outwardly from its outer periphery, a stop block supported by said housing and disposed in the path of said stop lugs, and a torsion spring connected between said lock discs under tension for urging said lock discs to rotate in opposite directions, said key ways being in alignment whenever said stop lugs are brought together on the same side of said stop block, said alignment of said key ways occurring whenever said drive shaft is in either said off position or said maximum time setting position, and said key moving from the key way of the outermost lock disc into the key way of the innermost lock disc upon said drive shaft reaching said off position.