US2705631A - Timing device - Google Patents

Timing device Download PDF

Info

Publication number
US2705631A
US2705631A US128387A US12838749A US2705631A US 2705631 A US2705631 A US 2705631A US 128387 A US128387 A US 128387A US 12838749 A US12838749 A US 12838749A US 2705631 A US2705631 A US 2705631A
Authority
US
United States
Prior art keywords
spring
rotor
lever
timing
drum
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US128387A
Inventor
Reichold Ludwig
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Individual
Original Assignee
Individual
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Individual filed Critical Individual
Priority to US128387A priority Critical patent/US2705631A/en
Application granted granted Critical
Publication of US2705631A publication Critical patent/US2705631A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01HELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H7/00Devices for introducing a predetermined time delay between the initiation of the switching operation and the opening or closing of the contacts
    • H01H7/08Devices for introducing a predetermined time delay between the initiation of the switching operation and the opening or closing of the contacts with timing by mechanical speed-control devices

Definitions

  • This *invention relates to a timing deviceand more particularly totiming devices which are adapted to pro- 1- vide a predetermined "timing period for eachloperation -l thereof and such'as commonly used "for controlling the operand machines, pin -ball'-machines, electric toasters and also door checks and the like.
  • Timing de 'ce whichis inexpensive to produce "and which may be easily operated *to' provide a desired ipredetermined time period.
  • urther object of the invention is to provide such a tim ng'f device which is controlled by: a suitable material," 1. preferably a plastic material, having lpermanent qualities and durable characteristics.
  • FIG. 1 is a front view of a timing device embodying myinventioti:
  • Fig. 2 is a side view thereof.
  • Fig. 3 is an enlarged front view, in central vertical section, of aporti'on of said device
  • FIG. 4 is aside-view, in central vertical section, of a door check embodying my invention in a modified form.
  • the numeral 5 denotes a base having an upright portion on which there is mounted a drum 6 having an axial post 7 extending therefrom and by means of which the said drum is horizontally mounted to the said upright portion.
  • the said post is surrounded by an annular shoulder 8 adjacent to the end wall 9 of the drum 6 and a disk 10 is rotatably mounted on the post between the said shoulder and a spacing collar 11 which is also mounted on said post and positioned between the disk 10 and the upright portion of the base 5.
  • a clamping nut 12 is threaded to the post 7 and, when tightened, is adapted to secure the disk 10 against rotation.
  • a rotor 13 is contained within the drum 6 and is axially and rotatably mounted therein by means of a trun nion 14, which rotates in a bearing in the end wall 9, and a shaft 15 which extends through the end wall 16 and is rotatable in a bearing therein.
  • An operating lever 17 is rotatably mounted on the shaft 15 and is disposed between the end of a hub 18, on the end wall 16, and a rotating member 19, preferably in the form of a disk, is secured to the shaft 15 against rotation thereon by suitable means such as a pin 20.
  • a pawl 21 is pivotally mounted on the lever 17, by means of a stud 22, and biased into contact with the surface of the disk 19 by means of a spring 23.
  • the said disk 19 may be in the form of a ratchet wheel having a series of teeth around the periphery thereof which are engaged by the pawl 21 to provide positive engagement for rotating the disk in one direction.
  • the lever 17 is urged to rotatewupon theshatt 15, by; meanstof a driving spring :24 which is anchored by one; end 25 to the disk 10 and by its opposite .end25a to, the;
  • Myimproved timingwdevice may be; adapted, for efiif ciently controlling the operation of such heating, devices as electric toasters wherein, asis commonlyknown, it is desired that the length of, the time intervals ,for successive toasting operations be reduced ,-in.p roportion to.the, rise of, the temperature in thetoaster so thatuniformly'toasted.
  • bread slices may be obtained regardless of wheth r the toaster is started fromtta cold condition, asinthefirst,
  • ticity ofwhich will increase as the. temperature, oflthe material rises, so that, the time periods provided, by.,s aid, timing device for a timing'operation will"'vary in accord ance with changes in the temperature of the device in which the said timing device is contained.
  • the material which I use for providing such variable timing periods is responsive to temperature changes in a heating device, which is controlled by my timing device, to provide shorter time periods as the temperature of the heating device rises, and thereby produce uniform results in cooking or toasting operations.
  • the timing device may be adjusted for providing longer or shorter time periods by reducing the tension in the driving spring 24 so that it will apply less torque to the rotor 13 against the plasticity of the material 26 and thereby increase the length of the time period, or apply more torque to the said rotor and reduce the length of the time period.
  • This adjustment of the driving spring 24 may be made by loosening the nut 12, rotating the disk 10 in the required direction to loosen or tighten the said spring, and then tightening the nut 12 so as to secure the said disk 10 in adjusted position.
  • the said disk may be connected to a suitable adjusting member which extends to the exterior of the device in which the timing device is used so that adjustment of the driving spring be made from the exterior of said device.
  • Such adjustments may also be determined by means of a dial and pointer, not shown, such as commonly used on timing devices.
  • my improved timing device may be combined with a suitable electric switch for timing the opening or closing of an Patented Apr; 1 955-1 particularly desirable fonusejn connectionwith my present invention, consists ofia pliable. :siliconeplastic, commonly-called, silicone rubber, or sili cone-putty, which resembles putty but has' 'stabil ity and ⁇ ;
  • the electric switch may include a spring bar 27 which is mounted on an insulating block 28and' has 'an electric contact 29 engaging a similar contact 30 on a resilient bar 31 which is also mounted on said block.
  • Each of said bars 27 and 31 may be provided with binding screws 32 and 33, respectively, for securing electric wires to said switch.
  • the device may include a stationary member in the form of a shell or container 36 having a material chamber 37 which is covered by a suitable closure '38.
  • a rotor 39 is rotatable in said shell upon a pivot 40 and in a bearing 41 in the closure.
  • a lever 42 is rotatable on the shaft 43 of the rotor and has a pawl 44 which engages a ratchet 45 on the'said shaft.
  • Aspring 46 surrounds the shell 36 and is secured at one end to the lever 42 and at the other end to an adjusting 47 which is secured to the shell by an adjusting nut
  • a cover 49 may be used to cover the entire device.
  • the device is "mounted to the frame of the door, illustrated at 50, and the lever 42 is secured to the door in any suitable conventional manner by the bearing 51.
  • a door check embodying this modified form of my invention provides a desired advantage over door checks of conventional form sinceit provides 'a uniform resistance for the full closing movement of the door and thereby prevents the rapid closing of the door during the initial portion of the closing movement which applies considerable strain upon the door check.
  • a timing device including a base, a stationary member secured to said base and 'having a material containing chamber therein, a rotor rotatable in said chamber, a spring member surroundingsaid stationary member, a lever rotatable on said rotor and connected to said 4 spring member, a ratchet member secured to said rotor, a pawl on said lever engageable with said ratchet to im- -part to saidrotor powerfrom said spring inone direction and to permit rotation of saidlever independently of said rotor to wind said spring, anchoring means securing said spring to said base, and means permitting adjustment of said anchoring means for varying the power imparted by the spring to the lever.
  • a timing device comprising a'base having an upright portion, a stationary drum, a co-axial post on said drum mounting the drum to the said upright portion, a rotor rotatable in said drum, a shaft projecting from said rotor through an end wall of said drum, a lever rotatable on said shaft, a connecting member secured to said shaft, a driving spring surrounding said drum, an anchoring disk rotatable on the post and havingone end of the said spring anchored thereto, the other end of the spring being connected to said lever, uni-directional connecting means on said lever for connecting the lever to the connecting member to drive the rotor in one direction, a plastic material between said drum and rotor for yieldingly resisting the rotation of said rotor'to retard the movement of said lever under the tension of the spring, and means for adjustably securing the said anchoring disk to the drum to vary the tension of the spring.
  • a timing device including a stationary drum, a rotor rotatable in said drum, a lever rotatably connected to said rotor, a driving spring adjustably connected to said drum, and connected to said lever for driving it in one direction, uni-directional ratchet means connecting saidlever to the rotor to impart power fromsaid spring for driving the rotor in one direction and to permit winding of the spring by rotation of said leverin an opposite direction independently of the rotor, a pliable plastic material between said drum and rotor yieldingly resistingthe rotation of said rotor by the spring, and means for adjusting said spring to vary the power imparted therefromto the rotor and thereby vary the speed of rotation. of the I'OlIOl'.

Description

April 5, 1955 1.. REICHOLD TIMING DEVICE Filed NOV. 19, 1949 5 III IIIIIHII II \Illllllllb I /[In R m m m 4, /1: WM Pam/m1.
UnitedStatesPatent O 2,705,631 TIMING DEVICE Ludwig'Reichold, Simsbury, Conn. Application Nat-mat 19,='1949, Serial No.''128,387
' 3 Claims: (01. 267-1) This *invention" relates to a timing deviceand more particularly totiming devices which are adapted to pro- 1- vide a predetermined "timing period for eachloperation -l thereof and such'as commonly used "for controlling the operand machines, pin -ball'-machines, electric toasters and also door checks and the like.
It is'an' object'of'this invention to provide a timing de 'ce whichis inexpensive to produce "and which may be easily operated *to' provide a desired ipredetermined time period.
urther object of the invention is to provide such a tim ng'f device which is controlled by: a suitable material," 1. preferably a plastic material, having lpermanent qualities and durable characteristics.
A still rur'th'er object 'ofthe invention is to:provide a timing device which may beadjusted =fordifferent timing: periods and which 1 will operatei'to provide a mechanical movement'or control an electric circuit.- 1
A still further and important object of this invention-is to provide such a timing device in which the plastic material used -is characterized by being responsive to temperature changes so as to vary the duration of the time periods providjed by said timing devicein accordance with such temperature changes and thereby render said timing device particularly adapted for use on such devices as automatic electric toasters and the like.
Fiirtlier objects and advantages of this invention will be'r'nore clearly understood from the followingidescription and from theaccompanying drawings in which:
A Fig. 1 is a front view of a timing device embodying myinventioti:
Fig. 2 is a side view thereof.
Fig. 3 is an enlarged front view, in central vertical section, of aporti'on of said device; 1
Fig. 4 is aside-view, in central vertical section, of a door check embodying my invention in a modified form.
In the embodiment of my invention illustrated in the drawings, the numeral 5 denotes a base having an upright portion on which there is mounted a drum 6 having an axial post 7 extending therefrom and by means of which the said drum is horizontally mounted to the said upright portion. The said post is surrounded by an annular shoulder 8 adjacent to the end wall 9 of the drum 6 and a disk 10 is rotatably mounted on the post between the said shoulder and a spacing collar 11 which is also mounted on said post and positioned between the disk 10 and the upright portion of the base 5. A clamping nut 12 is threaded to the post 7 and, when tightened, is adapted to secure the disk 10 against rotation.
A rotor 13 is contained within the drum 6 and is axially and rotatably mounted therein by means of a trun nion 14, which rotates in a bearing in the end wall 9, and a shaft 15 which extends through the end wall 16 and is rotatable in a bearing therein. An operating lever 17 is rotatably mounted on the shaft 15 and is disposed between the end of a hub 18, on the end wall 16, and a rotating member 19, preferably in the form of a disk, is secured to the shaft 15 against rotation thereon by suitable means such as a pin 20. A pawl 21 is pivotally mounted on the lever 17, by means of a stud 22, and biased into contact with the surface of the disk 19 by means of a spring 23. If desired, the said disk 19 may be in the form of a ratchet wheel having a series of teeth around the periphery thereof which are engaged by the pawl 21 to provide positive engagement for rotating the disk in one direction.
of such-appliances as slot machines, washing;
1 a: clockwise direction,
The lever 17 is urged to rotatewupon theshatt 15, by; meanstof a driving spring :24 which is anchored by one; end 25 to the disk 10 and by its opposite .end25a to, the;
said lever.
of-=the--rotorg 13. This materialds preferablya ,pl astic having .;the desired ,qualities foraparticular requirements m-the use of the timingdevice for dilferent timing operations. 1
A material found permanence "in, its consistency- In the operation of the embodimentwof ,my invention illustrated in the drawings, a timingtcyclemay beinitia'ted 'by rotating ,the lever=17 in a contra-clockwise direction. against the tension of the driving spring 24,.until it reaches a predetermined position which may be regulated by a,
suitable stop, (not ,shown-). .When the said lever is released, thespring ;24 will-urge-thesaid leverto rotate in of the disk, or ratchet wheel 19, and thereby connect the lever to the shaft 15 and cause rotationv of:therotor,-- 13 against the yielding resistance provided-by the plasticity. of the material 26- which-willtretard therotation of the, said rotor and thereby alsoretard therotation of the lever, 17 by the drivinggspring 24 andv consequently'provide,a,, time: interval'which'may be-used in performing different,
controlling operations, where a delayedactionisdesired.
Myimproved timingwdevice may be; adapted, for efiif ciently controlling the operation of such heating, devices as electric toasters wherein, asis commonlyknown, it is desired that the length of, the time intervals ,for successive toasting operations be reduced ,-in.p roportion to.the, rise of, the temperature in thetoaster so thatuniformly'toasted.
bread slices may be obtained regardless of wheth r the toaster is started fromtta cold condition, asinthefirst,
ticity: ofwhich will increase as the. temperature, oflthe material rises, so that, the time periods provided, by.,s aid, timing device for a timing'operation will"'vary in accord ance with changes in the temperature of the device in which the said timing device is contained. In effect, the material which I use for providing such variable timing periods is responsive to temperature changes in a heating device, which is controlled by my timing device, to provide shorter time periods as the temperature of the heating device rises, and thereby produce uniform results in cooking or toasting operations.
In the embodiment shown in the accompanying drawings, the timing device may be adjusted for providing longer or shorter time periods by reducing the tension in the driving spring 24 so that it will apply less torque to the rotor 13 against the plasticity of the material 26 and thereby increase the length of the time period, or apply more torque to the said rotor and reduce the length of the time period.
This adjustment of the driving spring 24 may be made by loosening the nut 12, rotating the disk 10 in the required direction to loosen or tighten the said spring, and then tightening the nut 12 so as to secure the said disk 10 in adjusted position. If desired, the said disk may be connected to a suitable adjusting member which extends to the exterior of the device in which the timing device is used so that adjustment of the driving spring be made from the exterior of said device. Such adjustments may also be determined by means of a dial and pointer, not shown, such as commonly used on timing devices.
As illustrated in Figs. 1 and 2 of the drawing, my improved timing device may be combined with a suitable electric switch for timing the opening or closing of an Patented Apr; 1 955-1 particularly desirable fonusejn connectionwith my present invention, consists ofia pliable. :siliconeplastic, commonly-called, silicone rubber, or sili cone-putty, which resembles putty but has' 'stabil ity and};
This rotation of the lever will causelthe end of the pawl 21 .to bind against the periphery;-
electric circuit. In the form shown, the electric switch may include a spring bar 27 which is mounted on an insulating block 28and' has 'an electric contact 29 engaging a similar contact 30 on a resilient bar 31 which is also mounted on said block. Each of said bars 27 and 31 may be provided with binding screws 32 and 33, respectively, for securing electric wires to said switch.
When the member 17 is moved downwardly, the electric switch is closed. As the said lever reaches the end of the timed cycle, the insulating abutment 34, at the end of the extension 35 on said lever, will'engage the spring bar 27 and move it away from the bar 31 and thereby separate the contacts 29 and 30 and break the electric circuit.
As illustrated in Fig. 4, my invention may be modified in order to provide a door check for checking the closing of a door to prevent it from slamming. In this form, the device may include a stationary member in the form of a shell or container 36 having a material chamber 37 which is covered by a suitable closure '38. A rotor 39 is rotatable in said shell upon a pivot 40 and in a bearing 41 in the closure. A lever 42 is rotatable on the shaft 43 of the rotor and has a pawl 44 which engages a ratchet 45 on the'said shaft. 7
Aspring 46 surrounds the shell 36 and is secured at one end to the lever 42 and at the other end to an adjusting 47 which is secured to the shell by an adjusting nut A cover 49 may be used to cover the entire device.
In the operation of the door check illustrated, the device is "mounted to the frame of the door, illustrated at 50, and the lever 42 is secured to the door in any suitable conventional manner by the bearing 51.
When the door is opened, it will wind the spring 46. As' the door is released, the spring will move it towards closed position against the tension of the plastic material 52 which is contained in the material chamber 37 betweenthe shelljfi and the rotor 39. This material is of the same nature as that used in the above described timing device and will retard the closing action of the door and thereby prevent slamming. Tension of the spring 46, to control the speed with which the door will close, may be adjusted by means of the adjusting disk 47.
A door check embodying this modified form of my invention provides a desired advantage over door checks of conventional form sinceit provides 'a uniform resistance for the full closing movement of the door and thereby prevents the rapid closing of the door during the initial portion of the closing movement which applies considerable strain upon the door check. .I claim:
.1. A timing device including a base, a stationary member secured to said base and 'having a material containing chamber therein, a rotor rotatable in said chamber, a spring member surroundingsaid stationary member, a lever rotatable on said rotor and connected to said 4 spring member, a ratchet member secured to said rotor, a pawl on said lever engageable with said ratchet to im- -part to saidrotor powerfrom said spring inone direction and to permit rotation of saidlever independently of said rotor to wind said spring, anchoring means securing said spring to said base, and means permitting adjustment of said anchoring means for varying the power imparted by the spring to the lever.
2. A timing device comprising a'base having an upright portion, a stationary drum, a co-axial post on said drum mounting the drum to the said upright portion, a rotor rotatable in said drum, a shaft projecting from said rotor through an end wall of said drum, a lever rotatable on said shaft, a connecting member secured to said shaft, a driving spring surrounding said drum, an anchoring disk rotatable on the post and havingone end of the said spring anchored thereto, the other end of the spring being connected to said lever, uni-directional connecting means on said lever for connecting the lever to the connecting member to drive the rotor in one direction, a plastic material between said drum and rotor for yieldingly resisting the rotation of said rotor'to retard the movement of said lever under the tension of the spring, and means for adjustably securing the said anchoring disk to the drum to vary the tension of the spring.
3. A timing device including a stationary drum, a rotor rotatable in said drum, a lever rotatably connected to said rotor, a driving spring adjustably connected to said drum, and connected to said lever for driving it in one direction, uni-directional ratchet means connecting saidlever to the rotor to impart power fromsaid spring for driving the rotor in one direction and to permit winding of the spring by rotation of said leverin an opposite direction independently of the rotor, a pliable plastic material between said drum and rotor yieldingly resistingthe rotation of said rotor by the spring, and means for adjusting said spring to vary the power imparted therefromto the rotor and thereby vary the speed of rotation. of the I'OlIOl'.
References Cited inthe tile of this patent UNITED STATES PATENTS- f 1,655,776 Squires Jan. 10,1928 1,778,905 Mitchell Oct. 21, 1930 2,380,191 Sauzedde July 10, 1945 2,460,116 Bazley Jan. '25, 1949 2,503,143 Wasdell Apr. 4, 1950 FOREIGN PATENTS 288,667 Great Britain Apr, 10, 1928 OTHER REFERENCES Product Engineering, January f1 950,- pages 96 93, Silicone Putty as an Engineering Material. 7
US128387A 1949-11-19 1949-11-19 Timing device Expired - Lifetime US2705631A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US128387A US2705631A (en) 1949-11-19 1949-11-19 Timing device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US128387A US2705631A (en) 1949-11-19 1949-11-19 Timing device

Publications (1)

Publication Number Publication Date
US2705631A true US2705631A (en) 1955-04-05

Family

ID=22435125

Family Applications (1)

Application Number Title Priority Date Filing Date
US128387A Expired - Lifetime US2705631A (en) 1949-11-19 1949-11-19 Timing device

Country Status (1)

Country Link
US (1) US2705631A (en)

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2959981A (en) * 1957-07-03 1960-11-15 Svenska Flaektfabriken Ab Mechanical delaying device
US2965200A (en) * 1956-06-18 1960-12-20 Gen Motors Corp Damper for valve control
US2998953A (en) * 1957-06-21 1961-09-05 O'connor Chadwell Panhead
US3104861A (en) * 1963-09-24 Timer valve
US3160231A (en) * 1964-02-21 1964-12-08 Model Products Corp Rotary turntable
US3244382A (en) * 1962-07-06 1966-04-05 Blake Minden Vaughan Apparatus operative when a predetermined rate of movement occurs
US3907493A (en) * 1974-07-11 1975-09-23 Xerox Corp Visco-elastic dampener mechanism for fuser assembly
US6240598B1 (en) * 1997-06-25 2001-06-05 Architectural Hardware Group Limited Arrangement for controlling an angularly movable member

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1655776A (en) * 1926-11-26 1928-01-10 Merwyn H Squires Snubber
GB288667A (en) * 1926-12-10 1928-04-10 Henry Smith Improvements in and relating to means for damping or checking the movement of oscillatory bodies
US1778905A (en) * 1927-06-13 1930-10-21 Thomas B Mcadams Shock absorber for vehicles
US2380191A (en) * 1942-02-02 1945-07-10 Sauzedde Claude Shock absorber
US2460116A (en) * 1945-08-24 1949-01-25 Gen Electric Control device
US2503143A (en) * 1946-02-02 1950-04-04 Wasdell William Kenneth Shock absorber

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1655776A (en) * 1926-11-26 1928-01-10 Merwyn H Squires Snubber
GB288667A (en) * 1926-12-10 1928-04-10 Henry Smith Improvements in and relating to means for damping or checking the movement of oscillatory bodies
US1778905A (en) * 1927-06-13 1930-10-21 Thomas B Mcadams Shock absorber for vehicles
US2380191A (en) * 1942-02-02 1945-07-10 Sauzedde Claude Shock absorber
US2460116A (en) * 1945-08-24 1949-01-25 Gen Electric Control device
US2503143A (en) * 1946-02-02 1950-04-04 Wasdell William Kenneth Shock absorber

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3104861A (en) * 1963-09-24 Timer valve
US2965200A (en) * 1956-06-18 1960-12-20 Gen Motors Corp Damper for valve control
US2998953A (en) * 1957-06-21 1961-09-05 O'connor Chadwell Panhead
US2959981A (en) * 1957-07-03 1960-11-15 Svenska Flaektfabriken Ab Mechanical delaying device
US3244382A (en) * 1962-07-06 1966-04-05 Blake Minden Vaughan Apparatus operative when a predetermined rate of movement occurs
US3160231A (en) * 1964-02-21 1964-12-08 Model Products Corp Rotary turntable
US3907493A (en) * 1974-07-11 1975-09-23 Xerox Corp Visco-elastic dampener mechanism for fuser assembly
US6240598B1 (en) * 1997-06-25 2001-06-05 Architectural Hardware Group Limited Arrangement for controlling an angularly movable member

Similar Documents

Publication Publication Date Title
US2705631A (en) Timing device
US4313051A (en) Electric rice cooker with twice cooking timer
US2775047A (en) Drier control
US4257394A (en) Pressure cooker
US2917988A (en) Control device
US2571818A (en) Limit switch
US2784584A (en) Resetting device for vibration switches of laundry machines
US2106269A (en) Control device
US2295298A (en) Heating system
US3018340A (en) Electric switch mechanism
US3818157A (en) Dual cam pulse timer switch
US2282089A (en) Electric appliance
US2897304A (en) Humidistat
US2076290A (en) Timing mechanism
US2531138A (en) Timing apparatus
US2964933A (en) Program timer
US2912530A (en) Control switches
US3118027A (en) Electrical switch including viscously damped timing device
US2653196A (en) Modulating pulsator
US2806094A (en) Timing device
US2768253A (en) Timing apparatus
US2630501A (en) Time control mechanism
US3316371A (en) Centrifugally operated switch with rack and pinion micro-switch adjusting means
US2996585A (en) Timing mechanism
US2562546A (en) Timer