US2036595A - Timing mechanism for valves, electric switches, or other mechanical movements - Google Patents

Description

April 7, 1936 HV MCDOWELL, JR 2,036,595

TIMING MECHANISM FOR VALVES, ELECTRIC SWITCHES, OR OTHER MECHANICAL MOVEMENTS Filed Oct. 12, 1952 4 Sheets-Sheet l Tic]. l 27- 1N VENTOR.

ATTORNEY.

Apriij, 1936 H. M DQWELL, m 29636595 TIMING MECHANISM FOR VALVES, ELECTRIC SWITCHES,

OR OTHER MECHANICAL MOVEMENTS Filed Oct. 12, 1952 4 Sheets-Sheet 5 Y INVENTOR. V g Hay/'7 /%flowe/lJ/r BY 9W W ATTORNEY.

Aprfl 7, 19360 H MCDQWELL, JR 2,636,399b

TIMING MECHANISM FOR VALVES, ELECTRIC'SWITCHES, OR OTHER MECHANICAL MOVEMENTS Filed Oct. 12, 1932 4 Sheets-Sheet 4- IN VENTOR.

' ATTORNEY.

Patented Apr. 7, 1936 UNITED STATES PATENT OFFICE TIMING MECHANISM FOR VALVES, ELEC- TRIO SWITCHES, OR OTHER MECHANICAL MOVEMENTS 9 Claims.

This invention relates to means for the application of timing mechanism to control the flow of fluid or electric current through a conduit. As the application of its subject-matter to a variety of purposes will be readily apparent to those of skill in this art, the following description will relate specifically to its use for turning a gas cock after a predetermined interval of time has elapsed.

A principal object of this invention is to provide timing mechanism which is simple in operation, readily attachable to a member, the operation of which is sought to be time controlled, compact, and comparatively inexpensive. A further object is to provide such a mechanism which permits ordinary manual manipulation of the device to which it is applied without interference by or with such timing mechanism, and which also permits, without interference, the various usual and common adjustments of such time controlled devices. Still another object is the provision of such a device which will give an audible alarm or signal indicating the completion of its function of operating the valve.

A preferred embodiment of my invention is described and illustrated in the accompanying specification and drawings, but it is to be understood that I do not limit myself to such specific disclosure, as various modifications in assembly, arrangement, shape, relative proportions and positions, and functions of the whole as well as of various parts of the device may readily be suggested by those of skill in this art without departing from the spirit of my invention.

In the drawings Fig. 1 is a transverse section through my timing device showing it attached to a plug cock as commonly used on gas ranges; Fig. 2 is a plan view of the complete assembly; Figs. 3, 4, and 5 are sections as seen on the correspondingly-numbered lines of Fig. 1; Fig. 6 is a fragmentary section on an enlarged scale as seen on line 66 of Fig. 4; and Figs. 7, 8, and 9 are diagrammatic views showing the release mechanism in three different positions which it assumes during operation.

Referring with more particularity to the drawings, a gas cock of the type commonly used on ranges is indicated by H], consisting of a body I I having a tapered bore I2 and aligned threaded bosses i3 and M. A tapered plug l5 provided with a port I6 is rotatably mounted in bore 92, being urged to a gas-tight fit therein by a compression spring I! suitably attached to an extension on the lower end of the plug. Bosses I3 and I4 each have an opening or passageway through them, adapted to be put into communication with each other by port I6 or not, depending upon the position of plug 15. These bosses are exteriorly threaded, whereby the valve may be supported by having boss l3 screwed into a supply pipe or manifold [8. A nozzle [9 is threaded on boss 14 and discharges into and supports an air-mixing chamber (not shown) which in turn communicates with the burner (also not shown). This is the usual construction of gas cooking ranges.

The upper part of body I I has a portion of reduced diameter 29 upon which is mounted the casing 21 which encloses the control mechanism, a set screw 22 serving to secure it in place. Casing Eli is formed of two parts, the bottom part 23 being a fiat plate upon which the mechanism is supported, and the upper part 24 being box-like and adapted to enclose the mechanism. Plate 23 has a large hub or boss 25, the lower part of which is secured to body II as just mentioned, and the upper part of .which is reduced to a smaller diameter to provide a shoulder and bearing for a pulley 26. Hub 25 is bored to receive the upper part of plug [5 which extends therethrough and out the top of the casing a handle 2! is secured to the top of the plug for turning it. Just below the top of casing 24, valve stem l5 has a square or splined portion 28 upon which is mounted a plate 29 having a projecting lug or pin 3!]. (See Fig. 4.) To accommodate this lug a portion of the upper part of boss 25 is cut away as denoted by 31. Lug 30 extends beyond boss 25 into the upper part of pulley 26 in which an arcuate slot is cut to receive it, as indicated by 32. The length of each of these cut-out portions must be the amount of angular movement which it is necessary for the stem or plug l5 to have (in this case plus the width of lug 3E]. The ends of cut 3| serve as stops to limit the turning of the valve plug, while the purpose and use of slot 32 will be later described.

Pulley 26 is provided with a deep groove 33 to receive a tension spring 35, one end of which is hooked over a pin attached to the pulley, the other end being attached to a link 31 pivotally secured to a combined detent and release arm 38. Arm 38 is attached by a pin 39 to a link 40, and is free to swing at either end in. response to spring 35, link 43 in turn being pivotally attached through pin 39a to a bracket 4| secured to plate 23. This bracket has an upstanding portion 42 for the purpose of limiting the movement of link All in the direction of the pulley. Arm 38 is provided with a finger 43 at its outer end and a dog or tooth 44 intermediate its ends. Dog 44 is intended to coact with teeth formed in the periphery of pulley 26 and permit the latter to be turned in one direction only through the motion of arm 38 away from teeth 45 permitted by non-fixed pivotal point 39 and fixed pivotal point 39A when trip 43 is non-yieldingly held against interlock finger 53 or cam periphery 41. Teeth 45 are of novel form and have a function in addition to that of a ratchet, as will be later set forth.

A recess 45A is provided in the periphery of pulley 26 to give relief to dog 44 when same is in a position as far as possible towards pulley 28, in the case when pulley has turned off valve, as is illustrated in Fig. '7.

Rotatively supported in upper and lower clock mechanism plates 49 is a shaft or pintle 48 securely holding a disc timing cam 41 whose periphery has a section 58 cut away. Rotatively mounted on top of cam 47 on a boss 52 (see Fig. 6) is an interlock member 5| shaped to include a finger 53 which is urged by a flat spring 54 to abut against the sides of slot 5|], thus normally covering slot and also limiting the angular movement of interlock member 5|. It will be seen that one side of finger 53 of interlock member 5| is shaped and elevated above the periphery of cam 41, the function of which will be later explained.

Secured to shaft 48 so as to turn therewith is a spring barrel 55 having gear teeth about the upper portion of its periphery 55 and containing a clock spring 51. One end of the spring is attached to the spring barrel and the other end to a bushing 58. This bushing is prevented from turning in any convenient manner, as, for example,by having a square or fiat side portion 59 engaged by a suitable opening in the upper of clock plates 49. Secured to shaft 48 so as to turn with it and the spring barrel is a clutch member 65. This is a-dished circular piece of spring steel or other suitable material and exerts pressure on spur gear 5| mounted below clutch on shaft 48 and free to turn thereon. Gear 6| drives an escapement movement 62, such as is commonly found in watches and clocks, by means of gear train 83. Means for regulating the speed at which the escapement runs are indicated by 64; such escapements and regulating means being well known will not be further described, as they form no part of the present invention.

Mounted on top of casing 2| and protected by a dust cover 61 is the setting mechanism (Figs. 1 and 3). This comprises a large or minute wheel 58 which projects from the dust cover a small distance so as to easily turn with the fingers and a small or hour wheel 69 arranged to be turned by movement of the large one. The minute wheel is secured to the upper end of a shaft 10 rotatably held in a boss 7| formed on cover member 24 (see Fig. 6). On the lower end of shaft 10 is pinion I2 meshing with gear 56 on spring barrel 55. The minute wheel 68 is marked off into sixty spaces each representing a minute, while the hour wheel is marked from zero to three hours. The hour wheel has a hub '53 with four teeth (see Fig. 3) adapted to be engaged by suitable recess 14 on the minute wheel, the arrangement being such that the hour wheel makes one-quarter turn for every revolution of the minute wheel. Such mechanism is well known in revolution counters and odometers. The dust cover 67 is provided with openings '15 and 16 through which a portion of the timing wheels 88 and 69 may be viewed.

The operation of the mechanism will now be described: Assume that gas cock I0 is in the off position, and that the timing mechanism is set for zero time, the tripping mechanism will then be as shown in Fig. '7, lug 30 will be against one end of limiting slot 3| and ratchet wheel 26 will be turned due to the pull exerted by spring 35 so that one end of slot 32 is against lug 30, the pull of spring 35 also causing ratchet bar 38 to be pressed against the periphery of wheel 26, tooth 44 being accommodated in a cut-out clearance space in the wheel.

If now cock I0 is partly opened, as by the plug being turned through an angle of 45, for example, the ratchet wheel and associated parts will assume the positions shown in Fig. 4, lug 30 by its engagement with end of slot 32 carrying Wheel 25 in a clockwise direction through a corresponding angle against the pull of spring 35. Resilient lateral play of ratchet bar 38, which is necessary to permit dog 44 to ride over teeth 45 is provided for by the plurality of pivoted connections of links 31 and 40 through which bar 38 is secured to plate 23 and spring 35, said bar 31 and its said link connections being under tension of spring 35 as hereinbefore described. Ratchet bar 38 being, as aforesaid, urged by the tension of spring 35 against wheel 26, the dog 44 engages one of teeth 45 and prevents reverse movement of the wheel. As no time has been set on the timing mechanism, timing wheel 41 is positioned with slot 5| directly under finger 43, thus eing supported on interlock 5|. If time has been set, the timing wheel will have been rotated in a counter-clockwise direction to some position such as that shown in Fig. 8, finger 43 then resting on the periphery of timing wheel 41.

Referring again to Fig. 4, it will be plain that cock Hi can be turned to its off position or any intermediate position as often as desired without any interference from the mechanism or pull from spring 35. It can also be opened further against the pull of this spring, say to full opening, as shown in Fig. 8. Link 40 will permit, as above explained, ratchet bar 38 to be forced away from the ratchet wheel by teeth 44 riding over dog 45. It will still be possible to turn the valve off, or partly off, and on again to any extent and as often as desired without any interference from the timing mechanism, due to lug 30 being free to move in slot 32.

If it is desired to set the timing mechanism to allow the gas cock to remain open a definite amount of time, the minute wheel 68 is rotated in a clockwise direction by means of thumb or finger pressure on its exposed edge until the desired time is shown by the figures visible through openings 15 and T6 in dust cover El. One hour is shown as an example. Rotation of the minute wheel causes rotation of spring barrel 55, due to gears 56 and 72, together with shaft 48, timing wheel 41, and clutch member 65, also winding and putting tension on spring 51. Clutch 60 slips on the surface of spur gear 6|, so the setting movement is not retarded by necessity of turning the escapement B2 and gear train 53.

As soon as wheel 68 is released, spring 51 begins to unwind and return all parts to their initial position, the speed at which this takes place being governed by the escapement. The friction exerted by clutch 60 on its associated gear 6|, is such as to prevent slippage between them due to the power exerted by spring 51. As

previously mentioned, finger 43 is supported on the periphery of timing wheel 41, and it will here be in order to explain that the contact surfaces of teeth 45 and dog 44 are so shaped and inclined that the tendency of ratchet wheel 26 to rotate in response to the pull of spring forces the teeth out of engagement being balanced by the pull over the other end of this spring on ratchet bar 38 and the length of this bar to its point of support on wheel 41. As wheel 41 turns clockwise, finger 43 catches the finger 53 on interlock 5| uncovering slot 50. As soon as this happens, finger 43 falls into the slot (see Fig. 9) due to the tendency of teeth 44 and 45 to be forced out of engagement as just described, spring 35 then returns ratchet wheel 26 to its initial position, the end of slot 32 engaging lug 38 and turning plug I5 to the off position.

From a consideration of the foregoing, it will be evident that the time setting can be altered at any time during the interval set. The gearing between the timing dials 68 and 63 and the timing wheel 41 must, of course, be such that the latter makes slightly less than one complete revolution for the maximum possible time setting.

The audible feature of the device comprises a bell or gong 11 mounted on top of casing 2| adjacent the handle of the gas cock. A clapper I8 is attached to the stem of the cock by a light spring arm 19, and so positioned that it will strike the back wall of bell 11 just as the cock is closed.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent 1. In a device of the character described, the combination of means for opening and closing a conduit, timing mechanism, including detent releasing means, flexible detent mechanism comprising a link and an arm, said arm being connected by a floating pivot to said link, a casing, said link in turn being fixedly pivoted to said casing, resilient means, said flexible detent means being yieldingly urged by said resilient means toward operative relationship with said opening and closing means and being also adapted to be yieldingly held by said resilient means in operative relationship with said detent releasing mechanism.

2. In a device of the character described the combination of a plug valve having attached to its stem a handle for manual operation, and also having attached to said stem a lug for automatic closure, a bushing, a pulley rotatably mounted on said bushing concentric with said valve stem having an upper surface in the same plane as that of said closure lug, said pulley having in said upper surface an arcuate slot to receive said automatic closure lug, said slot being of a length sufficient to permit opening and closing movement of said valve without affecting the position of said pulley, said pulley being also provided with teeth for engagement by a dog forming part of detent mechanism for controlling the operation of such automatic closure means, detent mechanism, a

F spiral spring attached at one of its ends to a point adjacent to the periphery of said pulley, and after partially encircling the grooved periphery of said pulley being attached at its opposite end to said detent mechanism, one of the elements of said detent mechanism being provided with a dog to engage teeth on said pulley, and means to release said detent under the control of timing mechanism.

3. In a timing device of the character described, a conduit flow-controlling operating pulley, said 75 pulley being provided with a series of peripheral teeth and a peripheral recess, a spring normally tending to rotate said pulley in one direction, detent mechanism normally urged toward engagement of the periphery of said pulley by the tension of said spring, said detent mechanism comprising an arm and a link, said arm carrying a dog on one side adapted for engagement with the teeth of said pulley, said dog also being adapted to be received into said recess, said arm carrying on its other side at one end a trigger finger, said link being joined with said arm at one of its ends by a floating pivot connection, the other end of said link being fixedly pivoted with relation to the periphery of said pulley, timing mechanism including a cam having a peripheral cutaway portion and an interlock member provided with a finger adapted to cover the peripheral cutaway portion o-f said cam, the periphery of said cam being so placed with respect to said detent mechanism as to normally engage the trigger finger of said detent arm when its dog engages any of the teeth of said pulley, a spring normally resiliently impelling said interlock member to close by its finger the cut-away portion of said cam.

4. In a device of the character described, the combination of a plug valve having a stem, a handle attached to said stem for the manual operation of said valve, a lug also attached to said stem and extending radially at a right angle I therefrom, a pulley rotatably mounted on a bushing concentric with said valve stem and adapted for partial rotation in the plane of said lug, said pulley being provided with an arcuate slot to receive said lug, said slot being of a length suificient l to permit manual opening and closing movement of said valve Without eifecting the rotatable position of said pulley, said pulley being provided with peripheral teeth and with a peripheral recess, detent mechanism pivotedly mounted fixedly with relation to the periphery of said pulley, said detent mechanism being provided with a dog, said dog being adapted for engagement with the teeth of said pulley and being adapted also to be received in said recess, resilient means normally 1:

erating connection with said conduit flow-controlling member, a spring normally tending to urge said pulley through said lost-motion connection, in a direction to effect closure of said conduit flow-controlling member, said pulley being provided with peripheral teeth, detent mechanism having a dog adapted to engage said teeth on said pulley and normally urged toward engagement therewith by said spring, said detent mechanism comprising an arm and a link joined by a floatingpivot connection at respective ends, the opposite end of said link being fixedly pivoted with relation to said pulley and the opposite end of said arm being provided with a trigger-finger, a timing mechanism including a detent releasing means said releasing means being adapted through said trigger-finger to permit disengagement of said dog from the teeth of said pulley.

6. In a device of the character described, the combination of time-controlling mechanism including detent releasing means, said detent re- Lil leasing means including a timing wheel and a spring actuated interlock member, said timing wheel having a peripheral radially-disposed slot, said slot being normally covered by said springactuated interlock member, detent mechanism comprising an arm and a link, said arm carrying a finger at one end adapted for operative engagement with the periphery of said timing wheel and being pivoted by a floating pivot at its other end to said link, said link being pivoted at its end opposite that of its floating pivot connection with said arm, fixedly with relation to said detent releasing means.

7. In a device of the character described, the combination of a, plug valve having a stem and having attached to said stem a handle for manual operation and a lug for automatic closure, operating means for said lug including a spring and a pulley, said pulley having peripheral teeth, said spring tending to urge said pulley into actuating engagement with said lug in the direction for closure of said valve, detent means to control, through engagement with teeth on said pulley the closing urge of said spring, said detent means comprising an arm and a link, said arm carrying a trigger-finger at one end and a floating-pivot connection with said link at its other end, timing mechanism including detent releasing means, the end of said link of said detent means opposite said floating-pivot connection being pivoted with fixed relation to said detent releasing means, said detent releasing means comprising a timing cam and a spring-actuated interlock member, said timing cam having a radially disposed slot, said slot being normally covered by said spring-actuated interlock member but adapted to be uncovered to permit release of said pulley by said detent arm.

8. In a device of the character described, the combination of a plug valve having a stem and having attached to said stem a handle for manual operation and a lug for automatic closure, operating means for said lug including a spring and a pulley, said pulley having peripheral teeth, said spring tending to urge said pulley into actuating contact with said lug in the direction for closure of said valve, detent means to control, through the teeth on said pulley the closing urge of said spring, said detent means comprising an arm and a, link, said arm carrying a triggerfinger at one end and a floating-pivot connection with said link at its other end, the end of said link opposite said floating-pivot connection being pivoted with fixed relation to said valve, said arm also having a dog adapted for engagement with said teeth on said pulley, timing mechanism including detent releasing means, said detent releasing means comprising a timing cam and a spring-actuated interlock member, said timing cam having a radially-disposed slot, said slot being normally covered by said springactuating interlock member, but adapted to be uncovered by sliding engagement of the triggerfinger of said detent arm on the periphery of said timing cam to permit said trigger-finger to enter said slot thus to disengage said dog from said teeth and permit the closing of said valve.

9. In a device for automatically, under the control of timing mechanism, closing a conduit, and wherein a lost-motion connection between the conduit closing means and said automatic closure mechanism is provided to permit independent manual operation of said closure means without interference with said automatic closure mechanism, the combination of a timing cam having a cut-out portion, an interlock member mounted adjacent to said cam and with a limited range of rotative movement relative thereto, means urging said interlock member to close said cut-out portion, detent releasing mechanism adapted for engagement with said interlock member to permit the timing mechanism to remain in inoperative position and allow free use of manual control means without interference by or with said detent mechanism.

HUGH MCDOWELL, JR.

resilient

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