US2377461A - Timer - Google Patents

Description

, eilfect the starting Patented June 5, 1945 UNITED STATES PATENT orrlcs TIMER Cyrus Swift, Qhicago, Ill. Application December 20, 1942, Serial No. 423,760

Claims.

The present invention relates to a timer device and more particularly to an adjustable device operable after a predetermined time interval to or stopping of an associated mechanism. Generally speaking, the timing device of this invention includes a bellows having a valve through which air is vented when the bellows is collapsed. The bellows has an air inlet sized for admitting air into the bellows at a predetermined rate. When the bellows. is collapsed and air expelled therefrom, the rate at which air enters through the inlet as the bellows expands and when the vent valve is closed determines the time limit for the bellows to assume its normal ex panded shape.

When the bellows nears its fully expanded shape, an actuating device thereon opens the vent valve and effects a snap action control for the starting or stopping of an associated mechanism either by the closing or opening of an electrical circuit or by the actuation of a mechanical linkage.

It has been found that the usual timing devices employed at the present time of the clock or gear mechanism type are not entirely satisfactory as their accuracy is affected when subiected to changes in temperature and atmos-- pheric pressure, vibration, shock or other disturbances.

An object of the present invention, therefore, is to provide a simple timing device whose accuracy is unaffected when exposed or subjected to external disturbances.

Another object of this invention is to provide an accurate timing device adiustably operable by controlling the flow of air.

A further object of this invention is to provide a timing device which includes a snap action control for the starting and stopping of an associated mechanism.

Another and still further object of this invention is to provide a timing device having a bellows arrangement from which air is evacuated when the bellows is collapsed and including an air inlet sized to effect an exact time interval for expansion of the bellows arrangement.

A still futher object of this invention is to provide a timing device with anexpansion bellows arrangement having an air inlet sized for controlling the time interval required for the bellows arrangement to expand and also having a cam mechanism operated by the expanding bellows arrangement which effects a snap action control for the starting and stopping of an associated mechanism.

A further object of this invention is the previsicn in a timing device of an expansible bellows having different sized air inlets operable at dif ferent stages of the expansion thereof for controlling the time interval for expansion.

another and further object of this invention is the provision in a timing device of an expansible bellows having one air inlet sized for controlling an even rate of expansion of the bellows and another air inlet sized and operable near the end of the expansion for suddenly increasing the rate of expansion to a snap action.

A still further object of this invention is the provision in a timing device of a cam mechanism and an expansible bellows having a vent valve and an air inlet for controlling the time interval for expansion of the bellows with the cam mechanism being operable for controlling the opening and closing oi. the vent valve at predetermined positions of the bellows.

A further object of this invention is the provision of a timing device having an expansible bellows with a vent valve and an air inlet for controlling the time interval for expansion of the bellows and also having a cam mechanism operable for compressing the bellows and for controlling the opening and closing of the vent valve at predetermined collapsed and expanding positions of the bellows.

The novel features believed to be characteristic of the present invention are set forth with par-.

ticularity in the appended claims. The invention itself, however, both as to, its organization and manner of construction, together with further objects and advantages thereof may best be understood by reference to the following description taken in connection with the accompanying drawing, in which:

Figure 1 is a side view in elevation of a timer device constructed in accordance withthe principles of the present invention;

Figure 2 is an enlarged view similar to Figure 1, with portions broken away, illustrating details of construction of the timer device of this invention;

Figure 3 is a top plan view of the timer device illustrated in Figure 1;

Figure 4 is an enlarged fragmentary vertical cross-sectional view as seen in the plane taken substantially along the line IV-IV of Figure 1;

Figure 5 is an enlarged transverse cross-sectional view as seen in the plane taken substantially along the line V-V of Figure 2;

Figure 6 is an enlarged fragmentary bottom view in elevation as seen in the plane taken substentlelly along the line fl- V1 of Figure 2; and

Figure '7 is an enlarged fragmentary vertical cross-sectional view illustrating a modified form of construction in which an expanded bellows electrical contacts to open circuit to connect el lcal contests tor circuit as shown in Figures 1 and 2.

- t shown in Figures 1 and 2, the timing ill of the present invention generally in t so e valve chsnisrn by which viii/@1111 opened and closed device,

new: in Figure and which ier in spaced relation 'ver erts end it. Connection and Cilllllifi The bellow accuracy of the t" impaired when. sub The Instill is also rierzible and resilient and in its her e is expanded into abutment with the etc i? of the frame it. The plate ll is up as at (Fig. 2) for slidsbly recei hough the vent valve construction it.

'e i3 has tubular casing 2i threaded -rioh at one end for threaded engagement ugh the top wall or the bellows I2 and a. rercing plate 22 thereon. The valve casing 21 internally threaded at its upper end for receiving therein o valve oi the Schroeder" type which has on ezrteriorly threaded casing 23, a. spring casconnected to the cusing 23 and which terminates its lower end in an outwardly flared valve seat e. valve pin 23 having an outwardly tiered velve heed El for seating on the valve seat 25, and coil spring 28 embracing the valve pin 26 within the spring casing 24 for normally maintaining the valve head against its seat. It will be noted that the upper end of the valve pin 26 extends above the top 01' the tubular casing 2!.

Although the bottom of the bellows [2 may be directly connected to the base plate I6, it is preferred that a reinforcing plate 29 be interposed tlierebetween which, together with the base plate, forms it support for the air inlet mechanism !4.

The sir inlet l4 includes a casing 30 having an exteriorly threaded tubular end threaded through registered and internally threaded openings in the base plate is and reinforcing plate 29. The casing 30 extends upwardly within the interior of the bellows i2 and is so shaped as to provide a tapered inner surface 3!. An end wall 32 at the tapered end of the casing 30 is apertured as at it. The cylindrical end portion of the casing 30 is internally threaded for receiving therein a tapered restriction member 34 having a knurled actuating heed 35 on. one end thereof. One or more longitudinally extending grooves 36 (sce Fi 5) are provided transversely through the exterior threads on the restriction member 34 in order that air may flow from the atmosphere into the space between the tapered surfaces on the re striotion member and the casins- The rate of airflow by therestriction member and through the easing into the interior of the bellows I2 is dependent upon the size or the grooves I8, the area or the adjustable space between the restricr and the casing, and the length of tlcn morn the casing to flow or mber 34 has been illusmay be provided, on. members each run it is threaded 21g head thereo! in end of 3 casing e. predebetween the r tion member be provided. ll varying the size restriction members, the time inti o flow 0! a. given volume of air 7 air inlet may be con rolled. This .ction member would require the proslot 88, as shown in dotted lines o, n. the under side of the actuating head for air to enter the casing through 3%.. In this iorm oi. construction, as many hooves 38 are provided as there are longltudinell extending grooves 38.

A. cross member or plate 39, shaped similar to the base plate [8 or the cover plate IT, has attached thereto a pair oi! spaced rod-like members 4C and ll. Coxmection or each of the rod members to the plate 39 is by any suitable means such as threading, riveting, welding, brazing or the like. The members 40 and 4! are so spaced as to telescopically engage within the vertical tubular supports l8 and i9 and are sufficiently longer than the vertical supports as to extend from both ends thereof. The lower ends or the rod members are threaded for receiving thereon the abutment nuts 42 and 43. Abutment plates 44 and 45 are connected to the lower side of the base plate (8 and are suitably apertured tor slids-bly receiving therethrough the rod members.

A coil spring 48 embraces a. portion of the rod member 40 adjacent the cross member 39 and has one end seated against the cross member and its other end seated on the cover plate ll. Likewise, a. coil spring 41 embraces the rod member 45 in a. position interposed between the cover plate H and the cross member 39. The coil springs urge the cross member 39 away from the cover plate IT with the limit of relative movement therebetween being defined by the abutment between the nuts 42 and 43 and the abutment plates 44 and 45. It will be apparent that the distance between the cover plates l1 and the cross member 39 effected by the compression of coil springs 48 and 41 may be adjusted and varied by threading the nuts 42 and 43 longitudlnally along the threaded end portions of the rod members 40 and 4|.

As best shown in Figures 1, 2 and 3, a. cam arm it'll 48 has one end pivotally connected to the cross member 39 adjacent its under surface by a pivot 49, such as a cap screw or the like. The opposite end of the cam arm 48 extends over the portion of the valve pin 28 projecting outwardly of the casing 2| of the vent valve I3. As best shown in Figure 2, when the bellows i2 is in an expanded position and in abutment with the cover plates II, the end of the valve pin 28 projecting from the casing 2| of the vent valve i3 is in abutment with the cam arm 48 whereby the valve head 21 has been urged away from the seat 25 to open the valve for communication of the interior of the bellows and the atmosphere. 7

A stop pin 50 extends downwardly from the cross member 39 against which the cam arm 48 abuts for positioning the latter directly over the valve pin 26 as shown in Figure 3. The position of the cam arm is normally maintained by a leaf spring whose free end abuts against the cam arm and whose other end has a coil 52 for receiving therethrough a pin 53 for connecting the spring to the cross member 39.

A cam member 54 has an upper conical portion 55 and a reduced exteriorly threaded end portion 56 for connection with the cover plate H. The cam member 54 is so positioned on the cover plate that its longitudinal axis is in alignment with an edge of the cam arm 48 (Figure 3). An opening 58 is provided in the cross member 39 in axial alignment with the cam member 54 for a purpose to be now explained.

When the timing device if! is held so that manual pressure may be applied to the base plate It and the cross member 39, compression of the springs 46 and 41 is overcome, the cross member 39 is forced towards the cover plate H, the cam arm 48 is forced into abutment with the end of the casing 2| to open the valve therein and the bellows |2 collapsed towards the base plate i6. As the vent valve I3 is opened and the bellows i2 collapsed, air in the bellows is vented through the vent valve.

The normal relative position of the parts is illustrated in full lines in Figures and is the position of parts illustrated in Figures 1 and 2. When the cross member 39 has been urged towards the cover plate I! to its limit of movement, the relative position of parts is illustrated in dotted lines in Figures 1, 2 and 4. As the cross member 39 moves downwardly, the conical portion 55 of the cam member 54 enters into the opening 58 and simultaneously the cam arm 48 moves downwardly along the sloping surface of the cam member whereby it is urged away from the stop member 50 and against the leaf spring 5|. The limits of lateral movement of the cam arm 48 are shown in full and dotted lines in Figure 4. When the cam arm 48 has been moved laterally as shown in dotted lines in Figures 3 and 4, it has been moved out of alignment and abutment with the valve pin 26 and engages only an end portion of the valve casing 2|. The coil spring 28 of the vent valve |3 urges the released valve pin 28 to a position in which the valve head 21 is seated against the valve seat 25 thereby closing the vent valve. However, engage ment between the end of the casing 2| and the cam arm 48 maintains the bellows |2 collapsed until such time as manual pressure isreleased from the device.

A look 59 is provided for maintaining the bellows l2 collapsed when manual pressure on the device is released. This lock construction includes a tubular member 60 slidably embracing the upright tubular support IS. A laterally extending handle II is provided on the tubular member 40 for manual rotation thereof on the vertical support N. A pin 82 extends outwardly from the vertical support I! and seats within a slot 88 in the tubular member whereby the handle 6| turns the tubular member 60 around the vertical support between predetermined limits defined by the length of the slot. This pin and slot coaction permits relative rotative movement but eliminates the possibility of any relative axial movement between the tubular member 60 and the vertical support. A locking portion 84 extends radially from the tubular member 50 in a direction opposite to the handle 8|. A transverse slot 85 is provided in the locking portion so as to embrace an upwardly extending pin carried by the top 0! the bellows l2. If desired, reinforc- 111g plates 81 and 88 are provided on oposite sides 01 the bellows for receiving therein the pressntted or otherwise secured end of the pin 56. An

opening 69 in the'cover plate I! slidably receives therethrough the pin 88.

As shown in Figures 1 and 2', a pair of electrical contacts 10 and H are normally held spaced by a dielectric member 12 with the elements being connected to the under side or the cross member 39 by means of a rivet or screw 13. The contacts 10 and H are so positioned as to be in alignment with the pin 88. Conductors l4 and I5 connect the contacts 10 and TI to an associated mechanism (not shown) to be started in operation when the circuit is closed through abutment of the contact H and the contact 10.

When the timing device ID has been manually actuated whereby the cross member 39 is moved downwardly, the bellows .I2 is collapsed and the air therein vented to the atmosphere. The vent valve I3 is then closed by cooperation of the cam member 54 and cam arm 48 and, if desired, the collapsed bellows is looked in position by actuation of the locking mechanism 58 to a position as illustrated in Figure 3. The air inlet I4 is then adjusted to the position in which a predetermined time interval elapses for the flow of air into the bellows i2 to take the place of the volume of air vented therefrom when the bellows has been released and expands towards the cover plate As the vent valve ll is closed when the device is manually actuated to an operating position. the collapsed bellows |2 may be locked by the locking mechanism and manual pressure released from the cross member 38 which is then urged to a projected position by the coil springs 46 and 41. Release of the looking mechanism permits the bellows l2 to expand upwardly towards the cover plate l1 and the time interval for the bellows to reach its fully expanded position is predetermined by the rate 01' airflow through the adjustable air inlet H. The upward speed of the bellows I2 is controlled entirely by the rate 01' airflow through the air inlet l4.

When the top of the bellows l2 nearly approaches the cover plate H, the extended end of the valve pin 28 engages'the cam arm 4!. Continued upward movement of the bellows causes the valve head 2'! to be actuated away from its seat 25 thereby connecting the interior of the bellows to the atmosphere by a relatively large air inlet opening. The rush of a large volume of air into the interior or the not quite fully expanded bellows causes the latter to complete its expansion with a snap action. This snap action movement of the bellows at the end or its expansion causes the pin 85 to snap the contact H into immediate engagement with the contact 70. This snap action of the contsctc eliminates aw possibility of arcing therec contsct .10 anelcctrical ciris closed whereby an asnisrs may be started in operation. i" hing device ill of this inven- 3 for eflecting 5, pre

l, I .1. colors associated my device mny be of is provided in the al contcct 58 is operation.

c cl "ranted. opening is provided in the $9 in order that the arm ll carsomber or] distance suiidcicnt to break the engagelt between the contacts H and lb. This emotion of serves to open an electrical circu i by the conductors H and 75' where cssccic'cd mechanism in operation may be sto ped.

The timing device ill illustrated and described has been develop-ed prlmarily for use with delsyed action bombs lthough it is obviously usable with any mechanism for starting or stopping the latter by either opening or closing an electrlcal circuit. Gbvlously, the device is also capable of operation with. mechanical linkage for starting and stopping an associated mechanism. Should mechanical linkage be substituted for an electrical circuit, the linkage would take the place of the electrical contacts with the pin 68 coccting with a, lever member whose movement would be transmitted through the connected linkage.

It will be obvious from the foregoing that I have provided a timing device which is simple in construction, whose operation depends entirely on the control of the flow of air, and which is positive and accurate in its operation irrespective of the number of times the device is operated. It will also be apparent that the simplicity in design and construction of my timing device readily lends itself to mass production at a very nominal cost per unit.

While particular embodiments only of this invention have been illustrated, it will, of course, be understood that the invention should not be limited thereto, since many other modifications may be made and. therefore, it is contemplated by the appended claims to cover all such modifications as fall within the true spirit and scope of the present invention.

I claim as my invention:

1. A timer comprising a resilient hollow body, a vent valve for said body, an air inlet for said body defining an intake of smaller area than said a an associated opcrvent valve, means for collapsing said body for venting air therefrom through said vent valve to the atmosphere, said body partially expanding to a normally expanded shape by drawing air into the interior thereof from the atmosphere through said small air inlet, and means for opening said vent valve for communication between the atmosphere end the interior of said hollow body whereby the latter fully expands to said expanded shape by a snap action.

2. A timer construction comprising a. resilient bellows, a vent valve for said bellows, an adjustable air inlet for said bellows defining an intake of. smaller area than said vent valve, means for collapsing said bellows for venting sir therefrom through said vent valve to the atmosphere, s-id resilient bellows expanding to a normal ex- 1: ed shape by drawing air into the interior thereof from the atmosphere, and cam means for opening said vent valve for communication between the atmosphere and the interior of said bellows at o predetermined point during expansion oi the bellows whereby the latter then expands with snap action.

" timer construction comprising a frame ng relatively nlovsble portions, a bellows carr by one of said frame portions, 8. pair of fluid is ling means for connecting the interior of sold bellows with the atmosphere, said frame portions being movable relative to each other for collapsing said bellows, said collapsed bellows exp-snding at a rate determined by fluid drawn through one bleeding means, and means on the other of said frame portions for actuating the other bleeding means whereby said bellows fully expands at it faster rate.

d. A timer construction comprising a frame having relatively movable portions, telescopic means connecting said frame portions, resilient means normally maintaining said frame portions in one spaced relation, a normally expanded bellows carried by one of said frame portions, 9. fluid inlet for said bellows, a fluid vent valve for said bellows, said bellows being collapsed when said frame portions are moved relative to each other whereby fluid in the bellows is expelled through said vent valve, said bellows expanding toward its normally expanded condition at a rate determined by said fluid inlet, and a cam member carried by the other of said frame portions for engagement by said vent valve to fully open the latter whereby said bellows then expands at a faster rate.

5. A timer construction including a movable valve construction, resilient means normally maintaining said valve construction in one position, means for moving said valve construction to another position, cam means between said valve construction and said last means for opening and closing said valve construction during movement to said other position, said cam means including an abutment member for opening said valve when said moving means moves said valve toward said one position.

6. A timer construction including a. valve. spring means for normally maintaining said valve in one position, a member movable into abutment with said valve for moving the latter to another position, a cam member on said valve, a cam member on said abutment member, said cam members coacting to open and close said valve during movement thereof to said other position, said cam member on the abutment member engaging said valve to open the latter when said spring means moves said valve toward said one osition.

7. A timer construction comprising a supporting frame, a normally expanded resilient bellows carried by said supporting frame, a normally closed spring pressed vent valve for said bellows. an adjustable fluid inlet for said bellows, a member carried by said supporting frame for movement relative thereto, spring means normally maintaining said member in a projected position, said member being operable for collapsing said bellows, mechanism for holding said bellows collapsed and releasing said bellows therefrom, a

with said valve for opening the latter when pressure is applied to said actuating member to move the valve to one 01' said limits, and a cam member engageable with said actuating member during said movement of the valve for moving said cam member out of alignment with the valve.

9'. Ina timer, a valve construction movable between predetermined limits, said valve construction having a spring pressed valve pin normally closing said valve and a tubular casing housing said pin, a movable actuating member, an arm pivotaliy carried by said actuating member, an abutment stop on said actuating member !or limiting pivotal movement oi said arm in one direction, a spring associated with said actuating arm for normally maintaining said arm in abutment with said stop and in alignment with said valve pin and said tubular casingsaid arm moving said pin to open said valve and abutting said tubular casing for movement of the valve construction to one of its limits when said actuating member is moved, and a member having a sloping cam surface for engagement of an edge of said arm during said movement of the valve construction to said one limit for rocking the arm away from said stop and out of alignment with said valve pin whereby said arm engages only said tubular casing and said valve pin released to close said valve.

10. A contact actuating device comprising a body. 7

CYRUS SWIFT.

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