US2253752A - Timing device - Google Patents

Timing device Download PDF

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US2253752A
US2253752A US286082A US28608239A US2253752A US 2253752 A US2253752 A US 2253752A US 286082 A US286082 A US 286082A US 28608239 A US28608239 A US 28608239A US 2253752 A US2253752 A US 2253752A
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gear
lever
cam
shaft
face
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US286082A
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Kenneth E Bemis
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    • AHUMAN NECESSITIES
    • A47FURNITURE; DOMESTIC ARTICLES OR APPLIANCES; COFFEE MILLS; SPICE MILLS; SUCTION CLEANERS IN GENERAL
    • A47JKITCHEN EQUIPMENT; COFFEE MILLS; SPICE MILLS; APPARATUS FOR MAKING BEVERAGES
    • A47J37/00Baking; Roasting; Grilling; Frying
    • A47J37/12Deep fat fryers, e.g. for frying fish or chips
    • A47J37/1219Deep fat fryers, e.g. for frying fish or chips with means for lowering or raising the frying basket
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T74/00Machine element or mechanism
    • Y10T74/11Tripping mechanism
    • Y10T74/114Retarded
    • Y10T74/116Clock train

Definitions

  • This new timing device utilizes an electric mo tor as the driving and time control mechanism and thereby provides more accurate time control and ample power to insure eflicient and definite timed operation of apparatus whose operation is controlled thereby.
  • timing mechanism including driving means, in which the driving means is operated continuously and in which the timing means is controlledby frictional pickup with the driving means, thus eliminating inaccuracies which are usually introduced at 7 starting and stopping of the driving means, and also eliminating backlash.
  • Fig. 1 is a fragmentary front elevation of an apparatus with the invention embodied therein.
  • Fig.2 is a section. taken on line 2'-2 of Fig. 1.
  • Fig. 3 is a partial rear view of Fig. 1, showing only one of the timing devices. 7
  • Fig. 4 is an enlarged elevation of the takeup mechanism for the timer.
  • I Fig. 5 is a side elevation of the invention with the cover o'fsthe timer housing removed.
  • Fig. 6 is ahsectional plan view takenon line B'-6 of Fig. 5'.
  • This disclosure shows the invention applied to apparatus of the type disclosed in mycopendingapplicationpreviously referred to herein, and in which a plunger I0 is incorporated for supporting a basket II and for lowering the basket into and raising it out of a suitable cooking bath l2; and it also includes an operating lever whichthetimer housing is mounted on the front panel ofthe-cabinet l8.
  • a toggle link 19 forms an operative connection between an intermediate point 20 on lever l3 and the upper end of the plunger lfl asjindicated at 2
  • timing m'echanism is illustrated in connection-with the apparatus just. described, its application-is not limited to any particular timingoperations or in connection with any specific type of apparatus, since it can be applied to many difierent timing requirements and with various classes of apparatus. 7
  • the invention therefore consists of the timing apparatus-including the driving means, setting means and adjustments, time period initiating means and timepe'riod terminating means, and the apparatus .control. r
  • the setting means includes the setting element l3 indicated as a lever, and which may be mechanically actuated by known means (not shown), or may be manually actuated as shown, and which element is secured to its pivot I! as indicated at"24.
  • the pivot I"! is rotatably mounted in suitable bearings 25, shown as formed integral withthe timer housing I6 which is provided with a removablecover 26; the spacing between the'cover'26 and related 'face of the housinglG being sufiicient to permit free movement of the time adjusting lever 21.
  • the driven .means and time period terminating means consists of a gear 28 which is rotatably mounted on the pivot l-I'and has a cam 29 projecting from one side thereof with one edge formed.
  • the time period adjusting and initiating means consists of a cam 30having a cam face 3
  • This eam is rotatably mounted on the pivot l1 and has the time adjusting lever 21 affixed'thereto and projecting through the slot formed between the timer housing l5 and its cover, as previously mentioned.
  • a mounting head 32 Fixedly mounted on the inner end of the pivot I1 is a mounting head 32 on which a clutch finger 33 is mounted and which is formed of flat spring metal. These elements 32 and 33 are included in the setting means.
  • the adjusting means and indicating means consists of a pointer 34 fixed on the lever 21, and this pointer has an arm 35 which extends about the side of the cover and its end is releasably secured by the knurled screw 36 which functions to secure the lever 21 in any adjusted position.
  • the driving means and urging means limited as to the degree of emergence consists of a pinion 3'! which is in constant mesh with the gear 28 and has a cone 38 integral therewith, and this cone cooperates with the clutch drum 39 which is fixed on the shaft 40 as indicated at 4
  • the pinion 31 and its associated cone 38 are rotatable on the shaft 48, and the cone is made to cooperate frictionally to limited degree by meansof a compression spring 42 to provide sufficient driving value or emergence to drive the timing mechanism and operate the apparatus control, but insufficient to stop the motor when the pinion is heldor driven in reverse through the gear, thus forming a slip clutch.
  • the spring 42 is adjusted as to tension by means of the collar 43 which is slidable on the shaft 40 and releasably secured in adjusted position. Through this slip clutch, the pinion is urged to drive the gear and does drive the gear when no external driving effort is applied to the gear, but is subject to retrograde driving by this gear, and the pinion can be stopped at any time and the motor will continue to drive the
  • the shaft 48 is driven continuously at very slow speed by means of the motor 44 through a worm 45 and worm gear 46, and any desired number of timing devices can be operated by the shaft 48, in any desired sequence, or independently of each other.
  • the resetting means or apparatus control means such as is applied to the time-controlled device if), consists of a trigger 41 having a catch 48 for cooperation with the perpendicular face 49 of the time period terminating, timer resetting, and apparatus control cam 29, and this trigger is guided in a peripheral slot 58 formed by a collar in cooperation with the pinion 31, and this trigger is suspendedly supported on the end 52 of a lever 53 which is intermediately pivoted at 54 to the rear of the panel l8, and a connecting rod 55 connects between the lever 53 at 56 and the latch 51 at 58 and which latch is pivoted to the back of the panel l8 at 59.
  • Suitable bearings 69 are provided for the shaft 48.
  • the raising means for the plunger [8 is similar to that described in the copending application previously mentioned and consists of a fluid check Si, tension springs 62 and a connecting rod 63 which connects between the head of the fluid check cylinder and the plunger H) as respectively indicated at 64 and 65.
  • the handle i4 is shown in its normal position in Figs. 1 and 2 and in its depressed position in dotted lines at I4 inFig. 2.
  • the motor drives the shaft 49 continuously at very slow speed.
  • the lever 2! is adjusted and locked in position in accordance with the elapse-time Period of operation of apparatus desired.
  • the handle I4 is pulled down to the depressed position [4, the catch passes through the opening 23 and is engaged by the latch 51 as indicated in Fig. 3.
  • the clutch finger 33 engages the engaging face 49 of the cam 29, turning the gear 28 back, or counterclockwise viewing Fig. 5, and this gear backs up the pinion in a clockwise direction in opposition to the direction of rotation of the shaft, the cone 38 slipping in the drum 39 which is being constantly driven in its normal counterclockwise direction and at its normal speed.
  • timing mechanism is automatically reset for the next operation, and the adjusted position of the cam face 3
  • a timing device comprising; driving means; a driven gear; a pinion meshing with said gear and-a friction clutch for driving said pinion and driven by said driving means and limited as to the degree of emergence to permit manual retraction of said gear; a shaft having said gear rotatably mounted thereon; a manually operable lever fixedly mounted on said shaft, and a latch for latching said lever in a depressed position; a clutch finger fixedly mounted on said shaft and projecting radially; a first cam projecting from one face of said gear for cooperation with said clutch finger for retraction of said gear through operation of said lever; a second cam cooperatively-related to said clutch finger and cooperating therewith to release said finger from said first cam following a predetermined degree of retraction of said gear, for initiating a cycle of operation of said timing device; a trigger cooperatively related to said first cam and operatively associated with said latch and actuated by said first cam for releasing said latch and terminating a cycle of operation when said gear has been returned from its retracted position by said
  • said driving means including a drive shaft; said clutch comprising a clutch cone rotatably mounted on said drive shaft and a clutch, drum fixedly mounted on said drive shaft; resilient means urgingconstant cooperation of said clutch cone and saidclutch drum; and means for driving said drive shaft.
  • a timing device comprising; a pivot having a lever fixed on one end and a spring finger fixed on the other end; a cam plate rotatably adjustable on said pivot and having means for angularly adjusting said cam plate; said cam plate having a releasing face cooperatively related to said spring finger; a gear rotatably mounted on said pivot and having a cam provided with an engaging face and with a riding face, said spring finger being engageably related to said engaging face and adapted to ride over said riding face to engage said engaging face to drive said gear when said lever is actuated in one direction and urged by said releasing face to disengage from said engaging face as said lever is actuated to a predetermined degree in the opposite direction; a shaft and means for continuously driving said shaft in one'direction; a pinion rotatably mounted on said shaft and meshing with said gear, and a slip clutch cooperating between said pinion and said shaft and driving said pinion when said pinion is free of emergence by said gear and allowing said pinion to be driven by said gear in opposition to the direction

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  • Engineering & Computer Science (AREA)
  • Food Science & Technology (AREA)
  • Mechanical Operated Clutches (AREA)
  • Portable Nailing Machines And Staplers (AREA)

Description

Aug. 26, 1941.
, K. E. BEMIS TIMING DEVICE Filed July 24, 1959 in I i .V/MEW/Qr W KM fi Patented Aug. 26, 1941 UNITED I STATES. PATENT OFFICE 2.2533752 G, mm Kenneth E-."Bemis, Oakland, Calif. Q Application u1y24, 1939,.Ser ial No.k286,( l82 4 Claims. (c1.1'6i 1) I l3 whichhasya handle Hat one end, and a catch l 5 intermediate its length,and which lever This invention, a timing device, is an improvement over the timing mechanism disclosed in my copending application, Serial No. 244,450, filed December '7, 1938, now Patent 2,196,968 and directed to a deep-fat frying machine, in which application a clock works is utilized as thetime control and driving mechanism.
This new timing device utilizes an electric mo tor as the driving and time control mechanism and thereby provides more accurate time control and ample power to insure eflicient and definite timed operation of apparatus whose operation is controlled thereby.
The objects and advantages of the invention are as follows:
- First; to provide a timing device which is operated .under specific control of a constantly-running electric motor or other suitable driving mechanism. 7
' Second; to provide a timing device which can be adjusted accurately to any desired time-elapse period within its limits of adjustment, and which will provide absolute precision in timing periods.
Third; to provide timing mechanism including driving means, in which the driving means is operated continuously and in which the timing means is controlledby frictional pickup with the driving means, thus eliminating inaccuracies which are usually introduced at 7 starting and stopping of the driving means, and also eliminating backlash.
Fourth; to provide apparatus ofthe type outlined which is simple in construction, positive in operation, and which operates with absolute precision.
In describing this invention, reference will be made to the accompanying drawing, in which:
Fig. 1 is a fragmentary front elevation of an apparatus with the invention embodied therein. Fig.2 is a section. taken on line 2'-2 of Fig. 1.
Fig. 3 is a partial rear view of Fig. 1, showing only one of the timing devices. 7
Fig. 4 is an enlarged elevation of the takeup mechanism for the timer. I Fig. 5 is a side elevation of the invention with the cover o'fsthe timer housing removed. Fig. 6 is ahsectional plan view takenon line B'-6 of Fig. 5'.
I This disclosure shows the invention applied to apparatus of the type disclosed in mycopendingapplicationpreviously referred to herein, and in which a plunger I0 is incorporated for supporting a basket II and for lowering the basket into and raising it out of a suitable cooking bath l2; and it also includes an operating lever whichthetimer housing is mounted on the front panel ofthe-cabinet l8. A toggle link 19 forms an operative connection between an intermediate point 20 on lever l3 and the upper end of the plunger lfl asjindicated at 2|, and the plunger I0 isslidable; in the bearings 22, and a hole 23 isformed through the frontpanel N3 of the cabinet .t'o-permit passage of the catch IE to the rear of the panel when the lever I3 is depressed to the position I3, the catch l5 then projecting through the hole as indicated at 15.
'Although the timing m'echanism is illustrated in connection-with the apparatus just. described, its application-is not limited to any particular timingoperations or in connection with any specific type of apparatus, since it can be applied to many difierent timing requirements and with various classes of apparatus. 7
The invention therefore consists of the timing apparatus-including the driving means, setting means and adjustments, time period initiating means and timepe'riod terminating means, and the apparatus .control. r
The setting means includes the setting element l3 indicated as a lever, and which may be mechanically actuated by known means (not shown), or may be manually actuated as shown, and which element is secured to its pivot I! as indicated at"24.' The pivot I"! is rotatably mounted in suitable bearings 25, shown as formed integral withthe timer housing I6 which is provided with a removablecover 26; the spacing between the'cover'26 and related 'face of the housinglG being sufiicient to permit free movement of the time adjusting lever 21. The driven .means and time period terminating means "consists of a gear 28 which is rotatably mounted on the pivot l-I'and has a cam 29 projecting from one side thereof with one edge formed. perpendicular to the side of the gear forming an engaging face, and with the other edge inclined asshown to .form a riding face. The time period adjusting and initiating means consists of a cam 30having a cam face 3| for axial urgence. This eam is rotatably mounted on the pivot l1 and has the time adjusting lever 21 affixed'thereto and projecting through the slot formed between the timer housing l5 and its cover, as previously mentioned.
Fixedly mounted on the inner end of the pivot I1 is a mounting head 32 on which a clutch finger 33 is mounted and which is formed of flat spring metal. These elements 32 and 33 are included in the setting means.
The adjusting means and indicating means consists of a pointer 34 fixed on the lever 21, and this pointer has an arm 35 which extends about the side of the cover and its end is releasably secured by the knurled screw 36 which functions to secure the lever 21 in any adjusted position.
The driving means and urging means limited as to the degree of urgence consists of a pinion 3'! which is in constant mesh with the gear 28 and has a cone 38 integral therewith, and this cone cooperates with the clutch drum 39 which is fixed on the shaft 40 as indicated at 4|. The pinion 31 and its associated cone 38 are rotatable on the shaft 48, and the cone is made to cooperate frictionally to limited degree by meansof a compression spring 42 to provide sufficient driving value or urgence to drive the timing mechanism and operate the apparatus control, but insufficient to stop the motor when the pinion is heldor driven in reverse through the gear, thus forming a slip clutch. The spring 42 is adjusted as to tension by means of the collar 43 which is slidable on the shaft 40 and releasably secured in adjusted position. Through this slip clutch, the pinion is urged to drive the gear and does drive the gear when no external driving effort is applied to the gear, but is subject to retrograde driving by this gear, and the pinion can be stopped at any time and the motor will continue to drive the shaft 40.
The shaft 48 is driven continuously at very slow speed by means of the motor 44 through a worm 45 and worm gear 46, and any desired number of timing devices can be operated by the shaft 48, in any desired sequence, or independently of each other.
The resetting means or apparatus control means, such as is applied to the time-controlled device if), consists of a trigger 41 having a catch 48 for cooperation with the perpendicular face 49 of the time period terminating, timer resetting, and apparatus control cam 29, and this trigger is guided in a peripheral slot 58 formed by a collar in cooperation with the pinion 31, and this trigger is suspendedly supported on the end 52 of a lever 53 which is intermediately pivoted at 54 to the rear of the panel l8, and a connecting rod 55 connects between the lever 53 at 56 and the latch 51 at 58 and which latch is pivoted to the back of the panel l8 at 59. Suitable bearings 69 are provided for the shaft 48.
The raising means for the plunger [8 is similar to that described in the copending application previously mentioned and consists of a fluid check Si, tension springs 62 and a connecting rod 63 which connects between the head of the fluid check cylinder and the plunger H) as respectively indicated at 64 and 65.
The operation of the invention is as follows:
The handle i4 is shown in its normal position in Figs. 1 and 2 and in its depressed position in dotted lines at I4 inFig. 2. The motor drives the shaft 49 continuously at very slow speed. The lever 2! is adjusted and locked in position in accordance with the elapse-time Period of operation of apparatus desired. The handle I4 is pulled down to the depressed position [4, the catch passes through the opening 23 and is engaged by the latch 51 as indicated in Fig. 3.
As the handle is pulled down, the clutch finger 33 engages the engaging face 49 of the cam 29, turning the gear 28 back, or counterclockwise viewing Fig. 5, and this gear backs up the pinion in a clockwise direction in opposition to the direction of rotation of the shaft, the cone 38 slipping in the drum 39 which is being constantly driven in its normal counterclockwise direction and at its normal speed.
When the finger 33 is moved back a suflicient distance in accordance with the time adjustment of the lever 21, it rides up on the cam face 3| and is forced out in an axial direction, finally disengaging from the cam 29, which releases the gear 28 and the clutch 3B, 39 instantly picks the pinion up and therethrough drives the gear 28 in its normal direction until the engaging face 49 of cam 29 engages the catch 48 of the apparatus control, and thereby pulling the trigger 4! down, and this trigger, through lever 53, connecting rod 55 and latch 51, releases the catch l5 and thesprings 52 move the lever l3 back to its normal or original position, and this lever in turn, through its associated pivot ll swings the finger 33 back, the finger riding over the riding face 66 of the cam 29 until it snaps down under the engaging face 49 ready for the next operation.
Thus the timing mechanism is automatically reset for the next operation, and the adjusted position of the cam face 3| governs the element of elapsed time.
It will be understood that variations in construction and arrangement of parts, which variations are consistent with the appended claims, may be resorted to without detracting from the spirit or scope of the invention, or sacrificing any of the advantages thereof.
I claim:
1. A timing device comprising; driving means; a driven gear; a pinion meshing with said gear and-a friction clutch for driving said pinion and driven by said driving means and limited as to the degree of urgence to permit manual retraction of said gear; a shaft having said gear rotatably mounted thereon; a manually operable lever fixedly mounted on said shaft, and a latch for latching said lever in a depressed position; a clutch finger fixedly mounted on said shaft and projecting radially; a first cam projecting from one face of said gear for cooperation with said clutch finger for retraction of said gear through operation of said lever; a second cam cooperatively-related to said clutch finger and cooperating therewith to release said finger from said first cam following a predetermined degree of retraction of said gear, for initiating a cycle of operation of said timing device; a trigger cooperatively related to said first cam and operatively associated with said latch and actuated by said first cam for releasing said latch and terminating a cycle of operation when said gear has been returned from its retracted position by said clutch; and a spring operatively associated with said lever for returning said lever to its nondepressed position upon termination of a cycle of operation through release of said latch.
2. A:stru'cture as defined in claim 1 said driving means including a drive shaft; said clutch comprising a clutch cone rotatably mounted on said drive shaft and a clutch, drum fixedly mounted on said drive shaft; resilient means urgingconstant cooperation of said clutch cone and saidclutch drum; and means for driving said drive shaft.
3.- A structure as defined in claim 1; and means manually operable and associated with said second cam for adjusting the relative releasing position of said first cam to change the elapsed-time period of operation; said first cam having an engaging face and a riding face; said clutch finger riding over said riding face to engage said en'- gaging face for retraction of said. gear, and being declutched by said second cam following actuation of said lever to its depressed position.
4. A timing device comprising; a pivot having a lever fixed on one end and a spring finger fixed on the other end; a cam plate rotatably adjustable on said pivot and having means for angularly adjusting said cam plate; said cam plate having a releasing face cooperatively related to said spring finger; a gear rotatably mounted on said pivot and having a cam provided with an engaging face and with a riding face, said spring finger being engageably related to said engaging face and adapted to ride over said riding face to engage said engaging face to drive said gear when said lever is actuated in one direction and urged by said releasing face to disengage from said engaging face as said lever is actuated to a predetermined degree in the opposite direction; a shaft and means for continuously driving said shaft in one'direction; a pinion rotatably mounted on said shaft and meshing with said gear, and a slip clutch cooperating between said pinion and said shaft and driving said pinion when said pinion is free of urgence by said gear and allowing said pinion to be driven by said gear in opposition to the direction of rotation of said shaft when said gear is driven by said lever through the medium of said finger; and control means controlled by said gear for time controlled operation of apparatus.
KENNETH E. BEMIS.
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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2416139A (en) * 1945-01-08 1947-02-18 Babson Bros Co Milking timer system
US2562481A (en) * 1951-07-31 Timer mechanism
US2568049A (en) * 1947-10-31 1951-09-18 Frederick E Hummel Cooking utensil
US2572934A (en) * 1949-04-01 1951-10-30 Frederick E Hummel Egg boiler
EP0309435A1 (en) * 1987-09-24 1989-03-29 Nova Electro International N.V. Electric cooking apparatus
US5165329A (en) * 1990-06-12 1992-11-24 Moulinex (Societe Anonyme) Electric deep fat fryer

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2562481A (en) * 1951-07-31 Timer mechanism
US2416139A (en) * 1945-01-08 1947-02-18 Babson Bros Co Milking timer system
US2568049A (en) * 1947-10-31 1951-09-18 Frederick E Hummel Cooking utensil
US2572934A (en) * 1949-04-01 1951-10-30 Frederick E Hummel Egg boiler
EP0309435A1 (en) * 1987-09-24 1989-03-29 Nova Electro International N.V. Electric cooking apparatus
BE1000919A3 (en) * 1987-09-24 1989-05-16 Itt Ind Belgium Electric cooker.
US5165329A (en) * 1990-06-12 1992-11-24 Moulinex (Societe Anonyme) Electric deep fat fryer

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