US3307417A

US3307417A - Worm gear escapement

Info

Publication number: US3307417A
Application number: US385402A
Authority: US
Inventors: Gianni A Dotto
Original assignee: PR Mallory and Co Inc
Current assignee: Duracell Inc USA
Priority date: 1964-07-27
Filing date: 1964-07-27
Publication date: 1967-03-07
Anticipated expiration: 1984-03-07
Also published as: GB1049557A

Description

March 7, 1967 v I G. A. DOTTO WORM GEAR ESCAPEMENT 4 Sheets-Sheet 1 Filed July 27, 1964 INVENTOR.

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March 7, 1967 G. A. DOTTO WORM. GEAR ESGAPEMENI 4 Sheets-Sheet Filed July 27, 1964 Match 7, 1967 5. A. DOTTO 3,307,417

WORM GEAR ESCAPEMENT Filed July 27, 1964 4 Sheets-Sheet s INVENTOR. G/A/VN/ A. 00770 FIE. Z BY ATTORNEY Mar'ch7, G A -r0 WORM GEAR ESCAPEMENT 4 Sheets-Sheet 4 Filed July 27, 1964 NH UHHI INVENTOR. GlA/V/V/ A. Dorm ATTORNEY United States Patent Ofiice 3,307,417 Patented Mar. 7, 1967 3,307,417 WORM GEAR ESCAPEMENT Gianni A. Dotto, Dayton, Ohio, assignor to P. R. Mallory & Co., Inn, Indianapolis, Ind., a corporation of Delaware Filed July 27, 1964, Ser. No. 385,402 7 Claims. (Cl. 74-426) The present invention relates to an escapement, more particularly to escapements imparting an intermittent or step-by-step rotary motion output from a substantially constant rotary motion input. Such timed, intermittent rotary motion escapements are employed to periodically actuate control devices such as a switch means that in turn regulates the time sequence of operations embodied in washing machines and other similar devices.

In a device of this general nature, it is desirable that the escapement be actuated after a predetermined interval of time has elapsed. The escapement operates a control device such as a switch means having as a component thereof a series of cam operated switches. The

escapement with which the present invention is concerned is of the type having a substantially constant rotary motion input which is translated by the novel escapement into an intermittent, snap rotary motion output. The device would necessarily include a drive motor, a drive gear, an escapement, and a switch means that sequentially actuates a plurality of electrical circuits.

In control timer utilizing escapements, it is desirable that the timer be manually operable to modify the duration or sequence of operation by either shortening or skipping over the particular operations entirely. For this purpose the novel timer of the present invention is provided with a manually operable means coupled to a cam shaft so that an operator is able to modify the duration or sequence of operations of the timer in accordance with the desires of the operator.

Severalescapements presently available impart an intermittent or step-by-step snap rotary motion output from a substantially constant rotary motion input and are used in conjunction with a switch means to form a control timer. These several escapements utilize means for storage of energy during a first portion of a cycle, the storage cycle, and/or subsequently releasing the stored energy so stored during a second portion of the cycle, the release cycle. Generally, these escapements are satisfactory for limited purposes and are usually bulky and complicated and slow in operation. In the typical escapement the driving force is stored for a predetermined interval of time by a leaf spring that is either expanded or compressed thus storing energy. When the leaf spring is released from its expanded or from its compressed condition, the energy so stored provides a driving torque for a ratchet wheel and its associated driving means.

The use of an intermittent driving means provides the facility of periodic actuation of a particular event but in addition the driving means provides a method whereby switch contacts are displaced from a first contact to a second contact with such velocity that the contacts are not damaged for arcing does not occur between the contacts. Arcing occurs when a switch contact is slowly withdrawn from engagement with a first contact. It is seen the intermittent release of stored energy over a relatively short period of time is transferred to a ratchet wheel and then to a cam operated means which means controls the sequential operation of a plurality of switch devices.

The present invention provides an intermittent driving means whereby the leaf spring is replaced by a worm gear mechanism that is a simple, efficient, inexpensive, accurate, effective means that provides an intermittent driving force that regulates the sequential operation of a control timer.

Therefore, it is an object of the present invention to provide a novel rotary motion translating means utilized to translate a slow, continuous rotary motion to a rapid, intermittent rotary motion.

Another object of the present invention is to provide an escapement means that has a more positive, high velocity intermittent driving force.

Yet another object of the present invention is to provide an escapement in which each impulse or jump has a precise amount of travel without overtravel.

Another object of the present invention is to provide a novel worm gear escapement mechanism for actuating a plurality of multicontact electric switches, the worm gear escapement being inexpensive and accurate in construction, and more positive in its driving force.

Yet another object of the present invention is to provide a worm gear escapement mechanism having a pin driven in planetary fashion over camming surfaces which camming surfaces include rise and fall contours which cona plurality of multi-contact switches, the escapement having optimum reliability characteristics afforded by a construction having a minimum number of components.

The present invention in another of its aspects, rel-ates to novel features of the instrumentalities of the invention described therein for teaching the principal object of the invention and to the novel principles employed in. the instrumentalities whether or not these features and principles may be used in the said object and/ or in the said field.

With the aforementioned objects enumerated, other objects will be apparent to those persons possessing ordinary skill in the art. Other objects will appear in the following description, appended claims, and appended drawings. The invention resides in the novel construction, combination arrangement and cooperation of elements as hereinafter described and more particularly as defined in the appended claims.

The appended drawings illustrate several novel and different embodiments of the present invention and are constructed to function in the most advantageous modes devised for the practical application of the basic principles involved in the hereinafter described invention.

In the drawings:

FIGURE 1 is a perspective view of the present invention illustrating the novel worm gear mechanism.

FIGURE 2 is an enlarged sectional view of the present invention illustrating the worm gear mechanism in its initial position taken across the lines 2--2 of FIGURE 1.

FIGURE 3 is an enlarged sectional view of the present invention illustrating the worm gear immediately 3 prior to the actuation of a ratchet by the worm gear taken across the lines 2-2 of FIGURE 1.

FIGURE 4 is an enlarged sectional view of the present invention illustrating the worm gear immediately subsequent to the actuation of a ratchet by the worm gear taken across the lines 22 of FIGURE 1.

FIGURE 5 is an enlarged top view with portions thereof cut away of an embodiment of the present invention illustrating a shaft carrying a Belleville washer and showing the movement of the shaft and associated washer in full and dotted lines respectively.

FIGURE 6 is an enlarged top view with portions thereof cut away of the embodiment of FIGURE 5 illustrating the position of the shaft and associated Belleville washer immediately prior to the intermittent, forward movement of the shaft.

FIGURE 7 is an enlarged sectional view of another embodiment of the present invention illustrating an arm actuating means.

FIGURE 8 is an enlarged partial front view of the present invention illustrating a shaft incorporating therein an off center shaft and an associated pin to provide an actuating means, the intermittent movement of which is illustrated in full and dotted lines respectively.

FIGURE 9 is an enlarged sectional view of the invention of FIGURE 8 illustrating the off center actuating means and a cooperating tension spring, the sectional view taken across the lines 99 of FIGURE 8.

FIGURE 10 is an enlarged perspective view of the actuating means of FIGURE 8.

Generally speaking, the means and methods of the present invention relate to escapements for timing devices through the use of which it is possible to selectively control the sequential operation of a plurality of cam operated switches. The escapement of the present invention utilizes a drive means for providing a substantially constant rotary motion output. A gear reduction means is coupled to the drive means to effectively reduce the rotary motion output of the drive means to a prede termined speed. An escapement, more particularly a worm gear escapement, is mechanically coupled to the gear reduction means. The escapement includes an actuating means, preferably a shaft rotatable in a predetermined direction. A coded indicia follower means, preferably a pin, is fixedly coupled to the shaft and rotatable therewith. A plurality of coded indicia, preferably cams, are positioned concentric with the axis of the shaft. The coded indicia have rise and fall peripheral contours which the pin traverses as the shaft to which it is coupled rotates. As the shaft rotates, a tension spring means is compressed thereby storing energy as the pin rises along the rise contours of the cams as a result of the rotation of the shaft. The compressed tension spring releases the v stored energy as the pin falls along the fall contours of the cams. A worm gear coupled to the shaft provides a driving force to a ratchet means as the pin falls along the fall contours of the cams.

More particularly, the present invention relates to a worm gear escapement including a mounting means and a retaining means pivotably coupled to the mounting means; the retaining means carrying a shaft rotatably journalled thereto. A coded indicia follower means, preferably a pin, is fixedly coupled to the shaft and is rotatable with the shaft. A plurality of coded indicia, preferably cams, are fixedly coupled to the retaining means at a right angle to the longitudinal axis of the shaft. Each of the cams are concentric with the shaft and each of the cams has an arcuate extent of about 180 degrees. The cams include alternate rise and fall peripheral contours upon which the pin rides as the shaft rotates. A tension spring wound about the shaft is compressed as the pin rises on the rise contour of the cams thereby storing energy. The compressed tension spring releases the I stored energy as the pin falls along the fall contours of the cams. A worm gear is fixedly coupled to the shaft.

The worm gear is rotationally displaced as the tension spring is compressed, however, the rotational displace ment of the worm gear does not rotationally displace a ratchet means coupled to the worm gear. The worm gear is linearly displaced as the stored energy of the tension spring is released. It is seen that the worm gear does not experience a rotational displacement during the release of the stored energy. The ratchet is actuated by the linear displacement of the worm gear so as to provide a driving torque for an associated cam shaft. The ratchet is displaced with an intermittent motion of a predetermined increment and magnitude. I

Another embodiment of the present invention is an escapement including a mounting means and a retaining means pivotably coupled to the mounting means. The retaining means has two legs spaced apart in parallel relationship. A slot of predetermined length and position is cut into each leg of the retaining means.- A shaft is rotatably journalled to the retaining means by any suitable means such as planetary bearings or the like. An off center shaft is milled from the shaft, the off center shaft having its longitudinal axis spaced apart in parallel relationship to the longitudinal axis of the shaft. A pin of predetermined length is fixedly coupled to the off center shaft and at a right angle to longitudinal axis of the off center shaft. The pin and one of the slotsengage so as to prevent displacement of the pin An off center aperture of a gear interfits with the off center shaft such in such a manner that as the gear is rotated, the off center shaft is displaced through an arc whereas the shaft is substantially maintained in an initial position. A tension spring wound about the shaft and fixedly coupled thereto has one end coupled to the constantly rotating gear and is compressed as the shaft is maintained in its initial position and the gear rotating thereby storing energy. As the arcuate displacement of the gear approaches degrees from an initial position, the pin disengages with one of the slots thereby releasing the stored energy of the compressed spring thereafter rapidly rotating the pin and the shaft through an arc of about 180 degrees.- After rotat ing through the arc of about 180 degrees, the pin engages the second of the two slots which slot prevents further rotational displacement. A worm gear is Coupled to the shaft and rotatable therewith. A ratchet is coupled to the worm of the worm gear, the ratchet is actuated by the rotational displacement of the worm gear.

Referring now to the drawings, which illustrate the preferred embodiments of the present invention, the es capement apparatus is generally indicated by numeral 10. A drive means 11 which can be any suitable electrical drive means such as an electric motor or the like is coupled to a rotatable worm gear 12 that is continuously driven in a constant rotary fashion. It is seen, however, that the drive means of the worm gear could be intermittent if desired. Worm gear 12 is positioned so as to mesh with reduction gear 13 and thereby mechanically displace the reduction gear in the counter-clockwise direction. Reduction gear 13 is fixedly coupled to shaft 14 so that rotational displacement of the reduction gear also rotationally displaces the shaft in a like manner and in a like direction.

A retaining means 15 rotatably journals in its opposite extremities shaft 14. It is seen that shaft 14 could have either a floating characteristic with respect to the opposite extremities of the retaining means or that the shaft could be rotatably coupled to the extremities by any suitable means such as planetary bearings or the like. The axis of the shaft is substantially parallel to the longitudinal axis of the retaining means as shown in FIGURE 1. The extremity of shaft 14 to which gear 13 is fixedly coupled is retained by end facing 16 of the retaining means. Gear 12 is spaced from end facing 16 by the thickness of a washer (not shown). The washer is utilized to prevent the gear from frictionally rubbing against the end facing. such friction causing undue gear wear and as a result thereof cause inaccuracies to exist in the escapement. Mounted on the front side of the end facing, the face opposite the face that abuts the washer, is coded indicia 17. The coded indicia comprises two cams, each cam including alternate rise and fall contours. The apex of the rise portion of the contour is equal in height to approximately the distance between the valleys of adjacent teeth of ratchet 18. A coded indicia follower means 19, preferably a pin, is securely coupled to shaft 14 and is so placed so as to ride on the periphery of the coded indicia. Pin 19 is perpendicular to and passes through the longitudinal axis of the shaft. FIGURE 1 shows that the periphery of the coded indicia or cams has a rise portion that is substantially 180- degrees in length. Thereafter the fall portion is substantially at a right angle to the rise portion thus making the fall portion substantially instantaneous back to an initial position.

As disclosed hereinbefore, pin 19 rides on the periphery of the cams and therefore the pin will follow the contour of the cams or coded indicia. The rise portion of the coded indicia displaces shaft 14 along its longitudinal axis in the direction of arrow 20. Also the displacement of the shaft is along a line tangent to the periphery of ratchet 18. In so doing a ring or washer 21 fixedly coupled to shaft 14 compresses tension spring 22 that is wound about shaft 14 between gear 13 and ring 21. Compression of the tension spring stores energy until such time as the shaft is permitted to return to its initial position at which time the stored energy of the tension spring is released and manifests itself as a driving force for ratchet 18. Shaft 14 is allowed to return to its initial position when pin 19 reaches the fall portion of the coded indicia. As pin 19 falls, shaft 14 is displaced in the direction of arrow 23. In so doing the energy stored by the compression spring is released and as a result thereof the shaft is rapidly displaced in the direction of arrow 23. A worm 24 is fixedly coupled to the extremity of the shaft opposite the extremity thereof to which gear 13 is coupled. Worm 24 is rapidly displaced in the direction of arrow 23, as a result of the rapid displacement of shaft 14. The length of the displacement in the direction of arrow 23 approximates the length of the fall portion of the coded indicia or the cams which as disclosed hereinbefore is substantially equal to the distance between the adjacent valley portions of adjacent ratchet teeth of ratchet 18. It is seen that the displacement of the ratchet in the clockwise direction approximates the length of one tooth of the ratchet.

The pitch of the worm 24 is such that as shaft 14 rotates in the counter-clockwise direction, the displacement of the shaft and the worm in the direction of arrow 25) does not displace ratchet 18 in the counterclockwise direction. Likewise, because of the pitch of the worm 24 and the shape of the mating ratchet teeth, displacement of shaft 14 in the direction of arrow 23 will displace ratchet 18 in the clockwise direction through an are approximately equal to the distance between the adjacent valleys of adjacent ratchet teeth. Pawl 25 is pivotably staked to mounting frame 26 by any suitable means such as a stake or fixed stud. The pawl interfits with a valley of the ratchet in such a manner so as to permit motion of the ratchet in the clockwise direction only. The function of the pawl is to prevent displacement of the ratchet in the counter clockwise direction. Counter-clockwise movement is a retrograde movement which would have a deleterious effect on the ability of a control timer to perform sequential operations at a predetermined time after the initiation of the timing cycle.

A cam shaft 27 is rotatably journalled to the mounting frame by any suitable means such as by planetary bearings (not shown). Fixedly coupled to an extremity of the calm shaft is ratchet 18. As ratchet 18 is displaced in the clockwise direction by the intermittent movement in the direction of arrow '23 by worm 24, the cam shaft is like- Wise displaced in the clockwise direction. It is seen that the ratchet provides a driving torque for the cam shaft. Fixedly coupled to the cam shaft is a plurality of cams 28 having on their respective peripheries coded indicia of alternate rise and fall contours. Associated with each cam is a switch (not shown). The follower arm of a follower switch (not shown) rides on the peripheral contours of a cam and the switch is actuated in accordance with the rise and fall contours of the associated cam. It is seen that the alternate rise and fall contours control the sequential operation of the switch means.

Retaining means 15 is pivotably coupled to mounting frame 26 by rotatable worm gear 12, the axis of which serves as a pivot point for the retaining means. As disclosed hereinbefore, gear 12 is coupled to driving means 11 in such a manner that housing 29 of the driving means overlies the pivotable point of the retaining means so as to maintain the retaining means in a predetermined vertical position with respect to mounting frame 26. An L-shaped tab 30 is place-d with an extremity of the retaining means containing the worm gear to prevent vertical displacement of this portion of the retaining means.

Driving means 11 is securely coupled to mounting frame 26 by any suitable means such as a plurality of stakes 31. Stakes 31 serve several purposes the most obvious of which are to predeterminately seat the driving means with respect to worm gear 12, to prevent unnecessary and deleterious oscillation of the housing of the driving means, and to serve as a means to prevent vertical displacement of retaining means 15.

An S-shaped spring 32 has one curved portion thereof seated partially around one of the stakes 31 and a second curved portion thereof seated partially around a post 33. An arm 34 of the S-shaped spring overlies the end of shaft 14 opposite the extremity of the shaft that has thereon worm 24. As disclosed hereinbefore the retaining means is pivotable about the axis of worm 12. Arm 34 of the S-shaped springs displaces the axis of the shaft in such manner as to displace worm 24 into engagement with ratchet 18. In addition when shaft 14 is displaced in the direction of arrow 20, spring 32 has its arm 34 displaced in the direction of arrow 20 thus storing energy. As shaft 14 is displaced in the direction of arrow 23 the energy so stored by the displacement of the S-shaped spring is released and therefore aids in displacing shaft 14 in the direction of arrow 23.

FIGURES 2, 3 and 4 more clearly illustrate the operation of the novel escapement. A driving means 11 such as an electric motor rotates the worm gear with a constant rotary motion in the counter-clockwise direction. Worm gear 12 serves not only to translate the electrical energy of the motor to a rotatable mechanical energy but in addition serves to reduce the velocity of the mechanical output of the motor. Gear 12 meshes with speed reduc tion gear 13 to rotate the reduction gear in the counterclockwise direction at a predetermined peripheral speed. Gear 13 is fixedly coupled to a predetermined portion of shaft 14, thus the rotating gear rotationally displaces shaft 14 in the counter-clockwise direction with a constant peripheral speed. As shaft 14 is rotated in the counterclockwise direction, pin 19 perpendicular to the longitudinal axis of the shaft and projecting beyond the outer periphery of the shaft rides up the rise portion of the coded indicia 17. Riding up the coded indicia rotatably displaces not only the pin in the direction of arrow 20' but also rotatably displaces shaft 14 in the direction of arrow 20. In so doing tension spring 22 wound around shaft 14 is compressed between ring 21 and gear 13 thereby storing energy. Pawl 25 prevents a counter clockwise displacement of the ratchet as worm 24 is rotationally displaced in the direction of arrow 20. The coded indicia is broken into two arcuate portions that are concentric about the longitudinal axis of shaft 14. The arcuate extent of each portion of the coded indicia is about degrees. The longitudinal displacement of the shaft is equal to the. width of one of the teeth of the ratchet wheel. It is seen that the rise portion of the arcuate portion of the code-d indicia in the longitudinal direction must be substantially equal to the width of a ratchet tooth. As pin 19 falls along the fall portion of the coded indicia, the force stored by the compression spring is released as a driving force that rapidly displaces the shaft in the direction of arrow 23. Pawl 25 because of its construction and the fabrication of the ratchet teeth a driving force acting in the clockwise direction causes a clockwise displacement of the ratchet. Displacement of the ratchet imparts a clockwise driving torque that displaces the cam shaft carrying a plurality of earns 28 which action actuates a plurality of switches associated therewith. It is seen that the motion of shaft 14 imparted to ratchet 18 as a driving torque is intermittent and at pr determined intervals.

FIGURE and FIGURE 6 illustrate an embodiment of the present invention whereby worm 24 is replaced by a Belleville washer 3S fixedly coupled to shaft 14. In the initial position, the Belleville washer is positioned in a valley between two adjacent ratchet teeth. The major plane of the washer is perpendicular to the longitudinal axis of shaft 14, thus it is seen that when pin 19 is on the rise portion of the coded indicia, the washer is displaced in the direction of arrow 20 as well as upwardly as indicated by the dotted lines of FIGURE 5. After the washer passes over the apex of the ratchet tooth, it falls into the valley of the adjacent tooth. Thereafter the pin falls along the fall contour of the cams releasing stored energy, which energy acts through the shaft to displace the ratchet in the clockwise direction as disclosed hereinbefore and as shown in FIGURE 6.

FIGURE 7 illustrates a third embodiment of the present invention wherein shaft 14 is replaced by a non-rotatable arm 36. Coded indicia 17 is securely coupled to gear 13 by any suitable means such as by press fitting or by welding. Pin 19 no longer rotates, however, it is perpendicular to the longitudinal axis of the arm as shown in FIGURE 7. As the coded indicia is rotated by gear 13, the pin rides up the rise portion thereof thereby displacing the arm in the direction of arrow 20. As a result of the displacement of the arm in the direction of arrow 20, tip 37 of the arm rides out of the valley between adjacent ratchet teeth. Upon reaching the apex of a ratchet tooth, the tip travels therealong until it reaches an adjacent valley portion whereupon it falls into the adjacent valley portion of an adjacent ratchet tooth. Shortly thereafter pin 17 attains the fall portion of the coded indicia and thereafter falls along the fall portion. This action releases the energy stored by tension spring 22 displacing arm 35 in the direction of arrow 23 with a powerful and rapid motion thereby providing a driving force. The movement of arm 36 displaces the ratchet in the clockwise direction, the ratchet providing a driving torque to an associated cam shaft. A slot 39 cut in arm 36 interfits with a pin 40. The cooperation of the slot and the pin serves to position the retaining means with respect to the arm regardless of the position of the arm on the outer periphery of the ratchet thereby assuring proper cooperation between the various elements of the esc-apement.

The fourth embodiment of the present invention is shown in FIGURES 8, 9 and 10. An off center shaft 41 is milled from a portion of shaft 14'. The axis of the off center shaft will traverse through an are that has as its axis, the longitudinal axis of shaft 14. A pin 42 is securely coupled to the off center shaft and pnojects therefrom at a right angle to the axis of the off center shaft. The pin is of sufficient length to interfit with a first slot 43 of predetermined length cut in leg 44 of retaining means The first slot is of sufficient length to permit arcuate movement by the pin into engagement with the first slot. A second slot as of predetermined length is cut in leg 46 of retaining means 15'. Leg 45 is parallel to and predeterminately spaced from leg 44.

a wise direction with a continuous motion.

& Slot 45 is cut into leg 4-6 in such a manner that pin 42 experiences rotational displacement through an arc of about degrees when the pin disengages slot 43 and engages slot 45 or when pin 42 disengages slot 45 and engages slot 43.

A drive means (not shown) can be any suitable electrical drive apparatus such as an electric motor or the like is coupled to a rotatable worm gear 12 that is con- .tinuously driven in a constant rotary fashion. Worm gear 12 is rotatably positioned on mounting frame 26 to mesh with reduction gear 13. The worm gear mechanically displaces the reduction gear in the counter-clock- Reduction gear 13 carr es a sleeve portion 47 that has an off center .aperture 48 that interfits with the off center shaft. An L-shaped slotted portion 49 is cut into the sleeve 47 in such a manner that tension spring 22 having an end portion 56 that is at a right angle with the longitudinal axis of the spring interfits with the L-shaped slot. Tension spring 22' is comprised of two portions: a first portion 51 that is tightly wound about shaft 14 and a second portion 52 that is loosely wound about shaft 14. The tightly wound first portion of the tension spring positions the spring on shaft 14 whereas the loosely wound second portion serves to store rotational energy as the end portion 50 of the tension spring is rotationally displaced from an initial position. It is seen that since the gear and associated sleeve have a substantially floating characteristic on shaft 14' displacement of the gear and associated sleeve rotationally displaces end portion 5% of the tension spring without rotationally displacing shaft 14'. As end portion 5% is displaced in the counterclockwise direction, energy is stored by the second end portion of the tension spring. Although gear 13 substantially floats on shaft 14' aperture 48 displaces the axis of the off center shaft through a predetermined are that has as its axis the longitudinal axis of shaft 14. As shown in FIGURE 8 and FIGURE 9 as gear 13 is rotationally displaced in the counterclockwise direction, end portion 50 of the tension spring is also rotationally displaced. Pin 42 interfitting with slot 43 prevents shaft 14' from being rotationally displaced. Additional rotational displacement of end portion 50 further serves to store additional energy in the tension spring. As disclosed hereinbefore, aperture 48 r is positioned off center in the sleeve of the gear so as to interfit with the off center shaft 41. It is seen that as gear 13' is rotationally displaced, aperture 48 displaces the off center shaft through a predetermined arc. Displacement of the shaft through the predetermined are gradually displaces pin 42 carried by the off center shaft in the direction of arrow 53. Displacement of the pin in the direction of arrow 53 gradually withdraws the pin from slot 43. As the off center shaft approaches an arcuate displacement of approximately 180 degrees, the pin disengages slot 43. Energy stored in the tension spring is released thereby rapidly displacing shaft 14' in the counterclockwise direction as illustrated by the dotted lines of FIGURE 8. Pin 42 after displacement through an arc of about 180 degrees engages slot 45. The engagement of the pin with slot 45 prevents further arcuate displacement of the pin. It is seen that since the off center shaft is an integral part of shaft 14 the shaft is likewise displaced through an arc of about 180 degrees providing a driving force for ratchet 18. A wonm 24 on shaft 14' is displaced 180 degrees thereby rotationally displacing ratchet 18 in the clockwise direction approximately through an arc of about one tooth. The ratchet provides a driving torque to an associated cam shaft.

Further rotational displacement of the gear 13 displaces aperture 48 thereby arcuately displacing off center shaft 41. Pin 42 is displaced in the direction of arrow 54. As the off center shaft approaches an arcuate displacement of approximately 180 degrees, the pin disengages slot 45. Energy stored in the tension spring is released thereby rapidly displacing shaft 14' in the counter-clockwise di- 9 rection. Pin 42 after displacement through an arc of about 180 degrees engages slot 43. The engagement of the pin with slot 43 prevents further arcuate displacement of the pin. As as the pin is rapidly displaced through an arc of about 180 degrees, shaft 14' is likewise displaced through an arc of about 180 degrees. The ratchet associated with the worm is advanced in the clockwise direction through an are equal to about one ratchet tooth. Cam shaft 27 and cam 28 are likewise displaced in the clockwise direction through an arc equal to about one ratchet tooth.

While the invention is illustrated and described in its preferred embodiments, it will be understood that modifications and variations may be effected without departing from the scope of the novel concepts of this invention as set forth in the appended claims.

Having thus described my invention, I claim:

1. In a control timer, an escapement means for intermittently displacing an integrally connected ratchet wheel and cam carrying shaft comprising a mounting frame, drive means fixedly connected to said mounting frame providing a substantially constant rotary motion output, a worm gear escapement means connected to and driven by said drive means, said escapement including retaining means having one end thereof pivotally connected to said mounting frame and a free end, said retaining means including end facings supporting an axially di-splaceable and rotatable shaft, cam follower means fixedly connected to said shaft and rotatable therewith, cam means carried by one of said end facings including rise and fall contours, said follower means riding on said, contours of said cam means as said shaft rotates, spring means carried by said shaft for storing energy as said shaft is axially displaced in a first direction due to said follower means rising along said rise contours of said cam means, and worm gear means carried by said shaft rotatably meshing with a ratchet wheel of an integrally connected ratchet wheel and cam carrying shaft so as to have no rotational effect on said ratchet wheel and said cam carrying shaft as said worm gear is rotationally displaced and axially displaced in said first direction, said energy stored in said spring means released as said follower means falls along said fall contours of said cams causing said worm gear to be axially displaced in a second direction so as to engage with and advance said ratchet wheel and said cam carrying shaft with an intermittent motion of determined increments, and means including said integrally connected ratchet wheel and carrying shaft for pivotally displacing said Worm gear escapement out of mesh with said ratchet wheel as said cam shaft is manually displaced thereby allowing said cam carrying shaft to be rotatably displaced independent of said worm gear escapement to a desired position.

2. In a control timer, an escapement means for intermittently displacing an integrally connected ratchet wheel and cam carrying shaft comprising a mounting frame, a drive means fixedly connected to said mounting frame providing a substantially constant rotary motion output, a worm gear escapement means connected to and driven by said drive means, said escapement including retaining means having one end thereof pivotally connected to said mounting frame and a free end, said retaining means including end facings supporting an axially displaceable and rotatable shaft, cam follower means fixedly connected to said shaft and rotatable therewith, cam means carried by one of said end facings concentric with said shaft including rise and fall contours, said follower means riding on said contours of said cam means as said shaft rotates, spring means carried by said shaft for storing energy as said shaft is axially displaced in a first direction due to said follower means rising along said rise contours of said cam means, and worm gear means carried by said shaft rotatably meshing with a ratchet wheel of an integrally connected ratchet wheel and cam carrying shaft so as to have no rotational effect on said ratchet wheel and cam carrying shaft as said Worm gear is rotationally displaced and axially displaced in said first direction, said energy stored in said spring means released as said follower means falls along said fall contours of said cams causing said Worm gear to be axially displaced in a second direction so as to engage with and advance said ratchet wheel and said cam carrying shaft with an intermittent motion of determined increments, and means including said integrally connected ratchet wheel and carrying shaft for pivotally displacing said worm gear escapement out of mesh with said ratchet wheel as said cam shaft is manually displaced thereby allowing said cam carrying shaft to be rotatably displaced independent of said worm gear escapement to a desired position.

3. In a control timer, an escapement means for intermittently displacing an integrally connected ratchet wheel and cam carrying shaft comprising a mounting frame, a drive means fixedly connected to said mounting frame providing a substantially constant rotary motion output, a worm gear escapement means connected to and driven by said drive means, said escapement including retaining means having one end thereof pivotally connected to said mounting frame and a free end, said retaining means including end facings supporting an axially displaceable and rotatable shaft, cam follower means fixedly connected to said shaft and rotatable therewith, cam means carried by one of said end facings including rise and fall contours, said follower means riding on said contours of said cam means as said shaft rotates, tension spring means carried by said shaft for storing energy as said shaft is axially displaced in a first direction due to said follower means rising along said rise contours of said cam means, and worm gear means carried by said shaft rotatably meshing with a ratchet wheel of an integrally connected ratchet wheel and cam carrying shaft so as to have no rotational effect on said ratchet wheel and said cam carrying shaft as said worm gear is rotationally displaced and axially displaced in said first direction, said energy stored in said tension spring released as said follower means falls along said fall contours of said carns causing said worm gear to be axially displaced in a second direction so as to engage with and advance said ratchet wheel and said cam carrying shaft with an intermittent motion of determined increments, means including said integrally connected ratchet wheel and carrying shaft for pivotally displacing said worm gear escapement out of mesh with said ratchet wheel as said cam shaft is manually displaced thereby allowing said cam carrying shaft to be rotatably displaced independent of said worm gear escapement to a desired position and spring means biasing said worm gear into engagement with said ratchet Wheel.

4. In a control timer, an escapement means for intermittently displacing an integrally connected ratchet wheel and cam carrying shaft comprising a mounting frame, a drive means fixedly connected to said mounting frame providing a substantially constant rotary motion output, a worm gear escapement means connected to and driven by said :drive means, said escapement including retaining means having one end thereof pivotally connected to said mounting frame and a free end, said retaining means including facings supporting an axially displaceable and rotatable shaft, cam follower means fixedly connected to said shaft and rotatable therewith, cam means carried by said end facings located at said pivotally connected end of said retaining means, said cams concentric with said shaft and including rise and fall cont-ours, said follower means riding on said contours of said cams as said shaft rotates, spring means carried by said shaft for storing energy as said shaft is axially displaced in a first direction due to saidfollower means rising along said rise contours of said cam means, and worm gear means carried by the extremity of said shaft supported by said end facing at said free end of said retaining means, said worm gear rotatably meshing with a ratchet wheel of an integrally connected ratchet wheel and cam carrying shaft so as to have no rotational effect on said ratchet wheel and said cam carrying shaft as said worm gear is rotationally displaced and axially displaced in said first direction, said energy stored in said spring means released as said foll-ower means falls along said fall contours of said cams causing said worm gear to be axially displaced in a second direction so as to engage with and advance said ratchet wheel and said cam carrying shaft with an intermittent motion of determined increments, and means including said integrally connected ratchet wheel and carrying shaft for pivotally displacing said worm gear escapement out of mesh with said ratchet wheel as said cam shaft is manually displaced thereby allowing said cam carrying shaft to be rotatably displaced independent of said worm gear escapement to a desired position.

5. In a control timer, an escapement means for intermittently displacing an integrally connected ratchet wheel and cam carrying shaft comprising a mounting frame, a drive means fixedly connected to said mounting frame providing a substantially constant rotary motion output, gear reduction means connected to said drive means reducing said rotary motion output of said drive means to a predetermined speed, a worm gear escapement means connected to and driven by said gear reduction means, said escapement including retaining means having one end thereof pivotally connected to said mounting frame and a free end, said retaining means including a pair of end facings in spaced parallel relationship, said end facings supporting an axially displa-ceable and rotatable shaft, cam follower means fixedly connected to said shaft and rotatable therewith, at least two cams carried by said end facings located at said pivotally connected end of said retaining means, said cams concentric with said shaft and having an arcuate extent of about 180 and including rise and fall contours, said follower means riding on said contours of said cams as said shaft rotates, a tension spring means carried by said shaft for storing energy as said shaft is axially displaced in a first direction due to said follower means rising along said rise contours of said cams, and worm gear means carried by the extremity of said shaft supported by said end facing at said free end of said retaining means, said worm gear rotatably meshing with a ratchet wheel of an integrally connected ratchet wheel and cam carrying shaft so as to have no rotational effect on said ratchet wheel and said cam carrying shaft as said worm gear is rotationally displaced and axially displaced in said first direction, said energy stored in said tension spring released as said follower means falls along said fall contours of said cams causing said worm gear to be axially displaced in a second direction so as to engage with and advance said ratchet wheel and said cam carrying shaft with an intermittent motion of determined increments, and means including said integrally connected ratchet wheel and carrying shaft for pivotally displacing said worm gear escapement out of mesh with said ratchet Wheel as said cam shaft is manually displaced thereby allowing said cam carrying shaft to be rotatably displaced independent of said worm gear escapement to a desired position.

6. In a control timer, an escapement means for intermittently displacing an integrally connected ratchet wheel and cam carrying shaft comprising a mounting frame, a drive means fixedly connected to said mounting frame providing a substantially constant rotary motion output, gear reduction means connected to said drive means reducing said rotary motion output of said drive means to a predetermined speed, a worm gear escapement means connected to and driven by said gear reduction means, said escapement including retaining means having one end thereof pivotally connected to said mounting frame and a free end, said retaining means including a pair of end facings in spaced parallel relationship, said end facings supporting an axially displaceable and rotatable shaft, cam follower means fixedly connected to said shaft and rotatable therewith, at least two cams carried by said end facings located at said pivotally connected end of said retaining means, said cams concentric with said shaft and having an arcuate extent of about and including rise and fall contours, said follower means riding on said cont-ours of said cams as said shaft rotates, a tension spring means carried by said shaft for storing energy as said shaft is axially displaced in a first direction due to said follower means rising along said rise contours of said cams, and worm gear means carried by the extremity of said shaft supported by said end facing at said free end of said retaining means, said worm gear rotatably meshing with a ratchet wheel of an integrally connected ratchet wheel and cam carrying shaft so as to have no rotational effect on said ratchet wheel and said cam carrying shaft as said worm gear is rotationally displaced and axially displaced in said first direction, said energy stored in said tension spring released as said follower means falls along said fall contours of said cams causing said worm gear to be axially displaced in a second direction so as to engage with and advance said ratchet wheel and said cam carrying shaft with an intermittent motion of determined increments, means including said integrally connected ratchet wheel and carrying shaft for pivotally displacing said worm gear escapement out of mesh with said ratchet wheel as said cam shaft is manually displaced thereby allowing said cam carrying shaft to 'be rotatably displaced independent of said worm gear escapement to a desired position, and spring means biasing said worm gear into engagement with said ratchet wheel.

7. In a control timer, an escapement means for intermittently displacing an integrally connected ratchet wheel and cam carrying shaft comprising a mounting frame, a drive means fixedly connected to said mounting frame providing a substantially constant rotary motion out-put, gear reduction means connected to said drive means reducing said rotary motion output of said drive means to a predetermined speed, a worm gear escapement means connected to and driven by said gear reduction means, said escapement including retaining means having one end thereof pivotally connected to said mounting frame and a free end, said retaining means including a pair of end facings in spaced parallel relationship, said end facings supporting an axially displaceable and rotatable shaft, cam follower means fixedly connected to said shaft and rotatable therewith, at least two cams carried by said end facings located at said pivotally connected end of said retaining means, said cams concentric with said shaft and having an arcuate extent of about 180 and including rise and fall contours, said follower means riding on said contours of said cams as said shaft rotates, a tension spring means carried by said shaft for storing energy as said shaft is axially displaced in a first direction due to said follower means rising along said rise contours of said cams, and worm gear means carried by the extremity of said shaft supported by said end facing at said free end of said retaining means, said worm gear rotatably meshing with a ratchet wheel of an integrally connected ratchet wheel and cam carrying shaft so as to have no rotational effect on said ratchet wheel and said cam carrying shaft as said worm gear is rotationally displaced and axially displaced in said first direction, said energy stored in said tension spring released as said follower means falls along said fall contours of said cams causing said worm gear to be axially displaced in a second direction so as to engage with and advance said ratchet wheel and said cam carrying shaft with an intermittent motion of determined increments, means including said integrally connected ratchet wheel and carrying shaft for pivotally displacing said worm gear escapement out of mesh with said ratchet wheel as said cam shaft is manually displaced thereby allowing said carn carrying shaft to be rotatably displaced independent of said worm gear escapement to a desired position, tab means for-med from said mounting frame and overlying said free end of said retaining means substantially preventing vertical movement of said retaining means, and spring means having one end fixedly connected to said mounting frame and the other end 13 thereof abutting said shaft biasing said worm gear into 2,739,485 engagement with said ratchet Wheel. 2,753,406 2,891,405 References Cited by the Examiner 2,904,728

UNITED STATES PATENTS 5 2,237,108 1 4/1941 Nichols 74426 2,636,588 4/1953 Grea et a1. 741.5

14 Sengebusch 74-1.5 X Pigman 74426 X Elmore 74--1.5 Staggs 741.5 X

DAVID J. WILLIAMOWSKY, Primary Examiner.

C. I. HUSAR, Assistant Examiner.

Claims

1. IN A CONTROL TIMER, AN ESCAPEMENT MEANS FOR INTERMITTENTLY DISPLACING AN INTERGRALLY CONNECTED RATCHET WHEEL AND CAM CARRYING SHAFT COMPRISING A MOUNTING FRAME, DRIVE MEANS FIXEDLY CONNECTED TO SAID MOUNTING FRAME PROVIDING A SUBSTANTIALLY CONSTANT ROTARY MOTION OUTPUT, A WORM GEAR ESCAPEMENT MEANS CONNECTED TO AND DRIVEN BY SAID DRIVE MEANS, SAID ESCAPEMENT INCLUDING RETAINING MEANS HAVING ONE END THEREOF PIVOTALLY CONNECTED TO SAID MOUNTING FRAME AND A FREE END, SAID RETAINING MEANS INCLUDING END FACINGS SUPPORTING AN AXIALLY DISPLACEABLE AND ROTATABLE SHAFT, CAM FOLLOWER MEANS FIXEDLY CONNECTED TO SAID SHAFT AND ROTATABLE THEREWITH, CAM MEANS CARRIED BY ONE OF SAID END FACINGS INCLUDING RISE AND FALL CONTOURS, SAID FOLLOWER MEANS RIDING ON SAID CONTOURS OF SAID CAM MEANS AS SAID SHAFT ROTATES, SPRING MEANS CARRIED BY SAID SHAFT FOR STORING ENERGY AS SAID SHAFT IS AXIALLY DISPLACED IN A FIRST DIRECTION DUE TO SAID FOLLOWER MEANS RISING ALONG SAID RISE CONTOURS OF SAID CAM MEANS, AND WORM GEAR MEANS CARRIED BY SAID SHAFT ROTATABLY MESHING WITH A RATCHET WHEEL OF AN INTEGRALLY CONNECTED RATCHET WHEEL AND CAM CARRYING SHAFT SO AS TO HAVE NO ROTATIONAL EFFECT ON SAID RATCHET WHEEL AND SAID CAM CARRYING SHAFT AS SAID WORM GEAR IS ROTATIONALLY DISPLACED AND AXIALLY DISPLACED IN SAID FIRST DIRECTION, SAID ENERGY STORED IN SAID SPRING MEANS RELEASED AS SAID FOLLOWER MEANS FALLS ALONG SAID FALL CONTOURS OF SAID CAMS CAUSING SAID WORM GEAR TO BE AXIALLY DISPLACED IN A SECOND DIRECTION SO AS TO ENGAGE WITH AND ADVANCE SAID RATCHET WHEEL AND SAID CAM CARRYING SHAFT WITH AN INTERMITTENT MOTION OF DETERMINED INCREMENTS, AND MEANS INCLUDING SAID INTEGRALLY CONNECTED RATCHET WHEEL AND CARRYING SHAFT FOR PIVOTALLY DISPLACING SAID WORM GEAR ESCAPEMENT OUT OF MESH WITH SAID RATCHET WHEEL AS SAID CAM SHAFT IS MANUALLY DISPLACED THEREBY ALLOWING SAID CAM CARRYING SHAFT TO BE ROTATABLY DISPLACED INDEPENDENT OF SAID WORM GEAR ESCAPEMENT TO A DESIRED POSITION.