US1919256A - Automatic timing device - Google Patents

Automatic timing device Download PDF

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US1919256A
US1919256A US439314A US43931430A US1919256A US 1919256 A US1919256 A US 1919256A US 439314 A US439314 A US 439314A US 43931430 A US43931430 A US 43931430A US 1919256 A US1919256 A US 1919256A
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spring
disk
arbor
sleeve
shaft
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US439314A
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Wilson E Porter
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NEW HAVEN CLOCK Co
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NEW HAVEN CLOCK CO
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    • GPHYSICS
    • G04HOROLOGY
    • G04FTIME-INTERVAL MEASURING
    • G04F3/00Apparatus which can be set and started to measure-off predetermined or adjustably-fixed time intervals with driving mechanisms, e.g. dosimeters with clockwork
    • G04F3/02Apparatus which can be set and started to measure-off predetermined or adjustably-fixed time intervals with driving mechanisms, e.g. dosimeters with clockwork with mechanical driving mechanisms
    • G04F3/027Apparatus which can be set and started to measure-off predetermined or adjustably-fixed time intervals with driving mechanisms, e.g. dosimeters with clockwork with mechanical driving mechanisms using electrical contacts, e.g. for actuating electro-acoustic device

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  • This invention relates to an improvement in timing devices designed for automatically effecting a given operation, such as the opening or closing of an electric circuit, after the lapse of a predetermined time-period.
  • the main obj cot of this invention is to provide, at a'low cost for manufacture, a simple, reliable and sn'iooth-aeting automatic timing device which may be readily reset to shorten or terminate a pr-eviously-selected time-interval, without occasioning such wear as would materially affect the operation of the device over a long period of service.
  • a further object of this invention is to provide anautomatic timing device of the character referred to which will provide against the overwinding of the driving-spring as the result of repeated setting and resetting.
  • my invention consists in an automatic timing device characterized by a driving-spring for the timetrain having one end frictionally anchored in place; and a ina1mally-operablc member frietionally connected to the frictionally-auchored driving-spring for tensioning the same; whereby the timing device may be set and reset without ov-erwinding the said spring.
  • My invention further consists in an automatic timing device characterized as above and having certain details of construction and combinations of parts as will be hereinafter described and particularly recited in the 35 claim.
  • FIG. 1 is a view in front elevation of one form which an automatic timing device constructed in accordance with my invention may 40 assume;
  • Fig. 2 is an edge view thereof upon a larger scale
  • Fig. 3 is a transverse sectional view taken on the line 22 of Fig. 1 but on a larger scale;
  • Fig. l is a sectional view taken on the line 1l of Fig. 2;
  • Fig. 5 is a similar view taken on the line 5 of-Fig. 2;
  • Fig. 6 is a corresponding view taken on the line 66 of Fig. 2;
  • Fig. 7 is a detached perspective View of the cocking-disk
  • Fig. 8 is 2. similar view of the control-disk.
  • Fig. 9 is a broken transverse sectional view illustrating another mode of frictionally anchoring the outer end of the main-spring to prevent the over-winding thereof.
  • I employ a winding-arbor or shaft 10 mounted for rotation in a rear assembly-plate 11 and an intermediate assembly-plate 12 and extending forward through a front assembly-plate 13 and a dial-plate 14.
  • the plates 11 and 12 are held in spaced relationship by means of pillars l5 and, sin'iilarly, the plates 12 and 13 are held in spaced relationship by pillars 1t).
  • the winding-arbor or shaft 10 is provided with a hook or pin 17 with which the inner end of a spiral driving-spring 18 is engaged in the usual manner of clock main-springs, while the outer end of the said spring frictionally engages the interior surface of the flange of a cup-shaped spring-barrel 19 concentrically positioned with respect to the arbor or shaft 10 and se cured to the forward face of the rear plate 11 by means of rivets 20.
  • a short reinforcing-strip 21 of spring-stock by means of a rivet 22, as clearly shown in Fig. 6 of the drawings.
  • a ratchet-wheel 3 Staked to the winding-arbor or shaft 10 just forward of the spiral spring 18 is a ratchet-wheel 3, upon the hub 2d of which is mounted, with freedom for rotation, a main-wheel 25 held in place by means of a retaining-washer 26 and carrying upon its forward face pawl 27 engaging with the teeth of the ratchet-wheel 23 under the urge of a spring 28.
  • the main-wheel 25 meshes into and drives a first pinion 29 mounted upon an arbor 30 carrying a second wheel 31 meshing into and driving a second pinion 82 mounted upon an arbor carrying a third Wheel 34.
  • third wheel 34 meshes into and drives a pinion 35 upon an arbor 36 which carries the fourth wheel 37 which, in turn, meshes into and drives a pinion 38 mounted upon the arbor 39 of an escapen enhwheel 40 coacting in the usual manner of time-trains with an escapement-lever 41 which imparts os illatory movement to a balance-wheel 42.
  • the wheels, pinions, etc., 25 to 42 inclusive, are positioned between the rear plate 11 and the intermediate plate 12, as clearly'shown in Fig. 2 of the drawings.
  • the forward end of the winding-arbor or shaft 10 is reduced in diameter to form a stem 43 upon which is mounted, with freedom for rotation, a setting-sleeve 44 having its inner end facing a forwardly-facing shoulder-.45 formed at the junction of the stem 43 and the intermediate portion 46 of the winding-arbor or shaft 16.
  • the said sleeve is retained in place against outward axial displacement upon the stem 43 of the arbor or shaft 10 by means of a bifurcated key 47 clipped into an annular groove 48 near the extreme forward end of the said stem.
  • a finger-button 49 Positioned upon the outer end of the sleeve 44 is a finger-button 49 provided with an inwardly-opening axial bore 50 for the reception of the outer end of the said sleeve, to which it is coupled by means of a couplingscrew 51.
  • the inner end'of the finger-button 49 mounts a pointer adapted to sweep over an annular series of graduations 53 engraved or etched upon the forward face of the dial-platel4 before ref-erred to.
  • the inner face of the sleeve 44 has placed against it a hardened friction-washer en gaged by a split spring-washer 55 engaging at its rear end with a hardened frictionwasher 56 resting against a washer 57 staked upon the winding-arbor or shaft 10 against the shoulder 45 thereon.
  • a cocking-disk 58 staked upon the sleeve 44 near the rear end thereof and formed. in its periphery with a notch 59, one wall of which is tangentially sloped, as shown in Fig. 7, to form a cam-surface 60 for coaction with a shoe 61 offsetting from the free end of a flexible switch-arm 62.
  • the opposite end of the switch-arm 62 is mounted upon a block 63 of insulating material forwardly offsetting from the intermediate plate 12 to which it is secured by means of screws 64.
  • the flexible switch-arm 62 also carries a contact 65 engageable with a similar contact 66 upon a complementary flexible switch-arm 67 when the shoe 61 is moved outwardly upon the pe riphery of the cocking-disk 58 as will hereinafter appear.
  • the inner end of the sleeve 44 is also formed with a bearin -surface 68 located immediately to the rear of the cocking-disk 58 and upon which is mounted, with freedom for limited rotation, what I shall for convenience of description refer to as a control-disk 69 which is formed with a notch 70 resulting in the formation of a drop-ofi nose 71 which, as will hereinafter appear, is adapted to overlap the cam-surface 60 of the adjacent cocking-disk 58.
  • the cocking-disk 58 is rigidly coupled to the sleeve 44 while the control-disk 69 may turn upon the bearing 68 of the said sleeve.
  • I provide the said cocking-disk with a rearwardly-projecting pin 72 extending through an arcuate slot 73 in the control-disk 69 and having one end of a helical spring 74 hooked over its rear end. The opposite end of the said spring is hooked over the rear end of a "pin '75 rearwardly projecting from the control-disk 69.
  • the spring 74 exerts a constant effort to turn the control-disk 69 with respect to the cocking-disk 58 in a direction required to cause the drop-off nose 71 of the former to overlap the cam-surface 60 of the latter.
  • the winding-sleeve 44 is turned and through the intermediary of the split spring-washer 55 and associated parts, effects the turning of the winding-arbor or shaft 10 and the winding of the driving-spring 18.
  • the cocking-disk 58 will also be turned so as to cause the cam-surface 60 thereof to move the shoe 61 of the switch-arm 62 outward and flex the latter so as to engage its contact 65 with the contact 66 of the switch-arm 67 and thus close the circuit.
  • said winding means including a shaft, a driving-spring for said time-train having one end frictionally anchored to a portion of the timer-structure andits other end fixedly conneced with said shaft, said setting means including a sleeve carried by said shaft and rotatable relatively thereto and provided with means whereby it may be manually rotated, means including a member rigid on said shaft and a spring member bearing thereagainst and against said sleeve to provide a frictional coupling between said sleeve and shaft whereby rotation of said sleeve in one direction will rotate said shaft to wind said spring, and means for preventing unwinding of said spring by reverse rotation of. said sleeve.

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Measurement Of Predetermined Time Intervals (AREA)

Description

July 25, 1933. I E PORTER 1,919,256
AUTOMATIC TIMING DEVICE Filed March 27, 1950 2 Sheets-Sheet l July 25, 1933. w. E. PORTER AUTOMATIC TIMING DEVICE Filed March 27, 1930 2 Sheets-Sheet 2 Patented July 25, 1933 UNITED STATES PATENT OFFICE WlILSON E. PORTER, OF NEW HAVEN, CONNECTICUT, ASSIGNOR TC THENEW HAVEN CLOCK COMPANY, OF HEXV HAVEN, CONNECTICUT, A CURPORATION AUTOMATIC TIMING DEVICE Application filed March 2-7, 1930. Serial No. 439,314.
This invention relates to an improvement in timing devices designed for automatically effecting a given operation, such as the opening or closing of an electric circuit, after the lapse of a predetermined time-period.
The main obj cot of this invention is to provide, at a'low cost for manufacture, a simple, reliable and sn'iooth-aeting automatic timing device which may be readily reset to shorten or terminate a pr-eviously-selected time-interval, without occasioning such wear as would materially affect the operation of the device over a long period of service.
A further object of this invention is to provide anautomatic timing device of the character referred to which will provide against the overwinding of the driving-spring as the result of repeated setting and resetting.
lVith. the above and other objects in view as will appear from the following, my invention consists in an automatic timing device characterized by a driving-spring for the timetrain having one end frictionally anchored in place; and a ina1mally-operablc member frietionally connected to the frictionally-auchored driving-spring for tensioning the same; whereby the timing device may be set and reset without ov-erwinding the said spring.
My invention further consists in an automatic timing device characterized as above and having certain details of construction and combinations of parts as will be hereinafter described and particularly recited in the 35 claim.
In the accompanying drawings Fig. 1 is a view in front elevation of one form which an automatic timing device constructed in accordance with my invention may 40 assume;
Fig. 2 is an edge view thereof upon a larger scale;
Fig. 3 is a transverse sectional view taken on the line 22 of Fig. 1 but on a larger scale;
Fig. l is a sectional view taken on the line 1l of Fig. 2;
Fig. 5 is a similar view taken on the line 5 of-Fig. 2;
Fig. 6 is a corresponding view taken on the line 66 of Fig. 2;
Fig. 7 is a detached perspective View of the cocking-disk;
Fig. 8 is 2. similar view of the control-disk; and
Fig. 9 is a broken transverse sectional view illustrating another mode of frictionally anchoring the outer end of the main-spring to prevent the over-winding thereof.
In the embodiment of my invention herein chosen for illustration in Figs. 1 to 8 inclusive, I employ a winding-arbor or shaft 10 mounted for rotation in a rear assembly-plate 11 and an intermediate assembly-plate 12 and extending forward through a front assembly-plate 13 and a dial-plate 14. The plates 11 and 12 are held in spaced relationship by means of pillars l5 and, sin'iilarly, the plates 12 and 13 are held in spaced relationship by pillars 1t).
Near its rear end the winding-arbor or shaft 10 is provided with a hook or pin 17 with which the inner end of a spiral driving-spring 18 is engaged in the usual manner of clock main-springs, while the outer end of the said spring frictionally engages the interior surface of the flange of a cup-shaped spring-barrel 19 concentrically positioned with respect to the arbor or shaft 10 and se cured to the forward face of the rear plate 11 by means of rivets 20. To heighten the frictional engagement between the outer coil of the spiral spring 18 and the inner face of the liange of the spring-barrel 19, I secure thereto a short reinforcing-strip 21 of spring-stock by means of a rivet 22, as clearly shown in Fig. 6 of the drawings.
Staked to the winding-arbor or shaft 10 just forward of the spiral spring 18 is a ratchet-wheel 3, upon the hub 2d of which is mounted, with freedom for rotation, a main-wheel 25 held in place by means of a retaining-washer 26 and carrying upon its forward face pawl 27 engaging with the teeth of the ratchet-wheel 23 under the urge of a spring 28.
The main-wheel 25 meshes into and drives a first pinion 29 mounted upon an arbor 30 carrying a second wheel 31 meshing into and driving a second pinion 82 mounted upon an arbor carrying a third Wheel 34. The
third wheel 34 meshes into and drives a pinion 35 upon an arbor 36 which carries the fourth wheel 37 which, in turn, meshes into and drives a pinion 38 mounted upon the arbor 39 of an escapen enhwheel 40 coacting in the usual manner of time-trains with an escapement-lever 41 which imparts os illatory movement to a balance-wheel 42.
The wheels, pinions, etc., 25 to 42 inclusive, are positioned between the rear plate 11 and the intermediate plate 12, as clearly'shown in Fig. 2 of the drawings.
The forward end of the winding-arbor or shaft 10 is reduced in diameter to form a stem 43 upon which is mounted, with freedom for rotation, a setting-sleeve 44 having its inner end facing a forwardly-facing shoulder-.45 formed at the junction of the stem 43 and the intermediate portion 46 of the winding-arbor or shaft 16. The said sleeve is retained in place against outward axial displacement upon the stem 43 of the arbor or shaft 10 by means of a bifurcated key 47 clipped into an annular groove 48 near the extreme forward end of the said stem.
Positioned upon the outer end of the sleeve 44 is a finger-button 49 provided with an inwardly-opening axial bore 50 for the reception of the outer end of the said sleeve, to which it is coupled by means of a couplingscrew 51. The inner end'of the finger-button 49 mounts a pointer adapted to sweep over an annular series of graduations 53 engraved or etched upon the forward face of the dial-platel4 before ref-erred to.
The inner face of the sleeve 44 has placed against it a hardened friction-washer en gaged by a split spring-washer 55 engaging at its rear end with a hardened frictionwasher 56 resting against a washer 57 staked upon the winding-arbor or shaft 10 against the shoulder 45 thereon.
For the purpose of controlling an electric switch or any other device which it may be desired to control, I employ a cocking-disk 58 staked upon the sleeve 44 near the rear end thereof and formed. in its periphery with a notch 59, one wall of which is tangentially sloped, as shown in Fig. 7, to form a cam-surface 60 for coaction with a shoe 61 offsetting from the free end of a flexible switch-arm 62.
The opposite end of the switch-arm 62, as shown, is mounted upon a block 63 of insulating material forwardly offsetting from the intermediate plate 12 to which it is secured by means of screws 64. The flexible switch-arm 62 also carries a contact 65 engageable with a similar contact 66 upon a complementary flexible switch-arm 67 when the shoe 61 is moved outwardly upon the pe riphery of the cocking-disk 58 as will hereinafter appear.
The inner end of the sleeve 44 is also formed with a bearin -surface 68 located immediately to the rear of the cocking-disk 58 and upon which is mounted, with freedom for limited rotation, what I shall for convenience of description refer to as a control-disk 69 which is formed with a notch 70 resulting in the formation of a drop-ofi nose 71 which, as will hereinafter appear, is adapted to overlap the cam-surface 60 of the adjacent cocking-disk 58.
As before pointed out, the cocking-disk 58 is rigidly coupled to the sleeve 44 while the control-disk 69 may turn upon the bearing 68 of the said sleeve. Now, for the purpose of coupling the control-disk 69 to the cockin g-disk 58 for movement therewith, but with capacity for limited relative movement, I provide the said cocking-disk with a rearwardly-projecting pin 72 extending through an arcuate slot 73 in the control-disk 69 and having one end of a helical spring 74 hooked over its rear end. The opposite end of the said spring is hooked over the rear end of a "pin '75 rearwardly projecting from the control-disk 69.
The spring 74, just above described, exerts a constant effort to turn the control-disk 69 with respect to the cocking-disk 58 in a direction required to cause the drop-off nose 71 of the former to overlap the cam-surface 60 of the latter. A
In the operation of my improved timer. the user grasps the finger-button 49 and turns the same clockwise until the pointer 52 carried tl'iereby registers with the graduation upon the dial 14 indicating the particular time-interval which it is desired to have elapse before the automatic accomplishment of a function such as the opening of a circuit, as is herein illustrated.
F or the purpose of description, let it be supposed that the desired interval is fifteen minutes.
As the finger-button 49 is turned clockwise, as above described, to register the pointer 52 with the desired graduation, the winding-sleeve 44 is turned and through the intermediary of the split spring-washer 55 and associated parts, effects the turning of the winding-arbor or shaft 10 and the winding of the driving-spring 18.
It will thus be seen that, although the sleeve 44. with its button 49 and associated disks 58 and 69 constitutes the setting means for the device, it will, through the frictional coupling described, operate to wind the spring 18.
Concurrently with the turning of the finger-button. 49 and the pointer 52, the cocking-disk 58 will also be turned so as to cause the cam-surface 60 thereof to move the shoe 61 of the switch-arm 62 outward and flex the latter so as to engage its contact 65 with the contact 66 of the switch-arm 67 and thus close the circuit.
As the cocking-disk 58 is turned, as just above'described, to move the shoe 61, the con trol-disk 69 will remain stationary until the shoe has been moved to a suflicient degree to permit the drop-oil nose 71 thereof to be snapped under it by the spring 74, this being ing spring 18 will immediately assert itself and slowly turn the arbor or shaft 10 counterclockwise under the control of the tin'ie-train already described. This counter-cloelnviso rotation of the arbor will also effect the similar rotation of the disks 58 and 69 and the pointer 52 for the reason that the sleeve 14.- is frictionally coupled to the said arbor by the split spring-washer 55and its ussociated parts.
Vhen the pointer 52 has reached the Zero mark upon the dial-plate ll, the drop-oil nose 71 of the control-disk 69 will have ridden out from under the shoe 61 which will immediately snap inward under the tension of the resilient switclnarm 62 with the result that the contact 65 will be separated from the contact 66 and the circuit thus broken, all as more completely shown and described in my co-pending application of the same title filed March 14, 1930,Serial No. 435,792, new Patent No. 1,831,605, dated Nov. 10, 1931.
Let it be supposed that the user wishes to shorten or terminate a previously-selected time-interval for which he has setthe timer. This ma readily be .ccomplished by turning the finger-button 49 counter-clockwise which will eliect a similn' turningmovement of the pointer 54, sleeve 44 and disks 58 and 69. During this resetting operation, the friction coupling action of the split spring-washer 55 will yield, since the winding-arbor or shaft 10 is held against any counter-clockwise movement by the ratchet-wheel 23, pawl 27, main-wheel 25 and the remainder of the timetrain. Thus, the driving-spring 18 is still. maintained under tension.
It will be readily seen that, were not provision made for its prevention, the repeated setting and resetting of the timing device would ultimately wind the driving-spring 18 to such degree as to prevent the further clockwise rotation of the finger-button 51 without breaking the said spring or some of the connecting parts.
In my improved device it will be noted that the outer end of the spiral driving-spring 18, instead of being fixedly anchored, as is its end which is connected to the arbor or shaft 10, is frictionally anchored by the frictional grip of its outer convolution assisted by the reinforcing-strip 21, upon the inner surface of the 'iange of the spring-barrel 19 so that when the said spring is wound to a predetermined degree, it will automatically overcome the frictional grip of its outer convolution upon the said spring-barrel and. cause a relative slippage and thus automatically relieve the said spring of any excess tension.
instead of effecting the frictional anchorage of the outer end of the spiral driving-spring by means of the frictional engagement thereof with the springarrel 19, 1 may effect a similar result by anchoring the outer convolution of the said spring "to the spring-barrel by means of a rivet 76 (Fig. 9) and frictionally anchoring the spring-barrel itself to the rear plate ll by providing it with a rearwardly-extending bushing bearing in the said plate 11 and provided at its rear end with a spring-washer 78 bearing against the rear face of the said plate and exerting a constant effort to engage the rear face of the spring-barrel with the front face of the said plate, as shown in Fig. 9 of the drawings.
It will be understood by those skilled in the art that my invention may assume varied physical forms without departing from my inventive concept and I, therefore, do not limit myself to the specific embodiment herein chosen for illustration, but only as indivated in the appended. claim.
I claim:
In an automatic timing device, the combination with the time-train and controlmechanism therefor, of manually-operable winding means, and mamially-operable setting means, said winding means including a shaft, a driving-spring for said time-train having one end frictionally anchored to a portion of the timer-structure andits other end fixedly conneced with said shaft, said setting means including a sleeve carried by said shaft and rotatable relatively thereto and provided with means whereby it may be manually rotated, means including a member rigid on said shaft and a spring member bearing thereagainst and against said sleeve to provide a frictional coupling between said sleeve and shaft whereby rotation of said sleeve in one direction will rotate said shaft to wind said spring, and means for preventing unwinding of said spring by reverse rotation of. said sleeve.
lVILSON E. PORTER.
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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2562481A (en) * 1951-07-31 Timer mechanism
US2565017A (en) * 1947-03-26 1951-08-21 Foster H Brown Interval timer
US3516244A (en) * 1968-06-17 1970-06-23 Ind Timer Corp Front chassis assembly for time delay or interval timers
US3864904A (en) * 1973-05-08 1975-02-11 Botho Jung Watch with an adjustable time interval hand

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2562481A (en) * 1951-07-31 Timer mechanism
US2565017A (en) * 1947-03-26 1951-08-21 Foster H Brown Interval timer
US3516244A (en) * 1968-06-17 1970-06-23 Ind Timer Corp Front chassis assembly for time delay or interval timers
US3864904A (en) * 1973-05-08 1975-02-11 Botho Jung Watch with an adjustable time interval hand

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