US3722294A

US3722294A - Dual adjustment cycling timer

Info

Publication number: US3722294A
Application number: US00183779A
Authority: US
Inventors: J Harris
Original assignee: Deltrol Corp
Current assignee: Deltrol Corp
Priority date: 1971-09-27
Filing date: 1971-09-27
Publication date: 1973-03-27
Anticipated expiration: 1990-03-27

Abstract

A continuous cycling timer in which the on and off periods are independently adjustable. A single motor drives two spring return timing discs through a clutch engaging one or the other. The disengaged disc resets to its starting point when the other disc is engaged. The timer load switch and clutch are controlled by a single actuator controlled by both timing discs. When the switch is closed, the on period timer operates. When the switch is open, the off period timer operates.

Description

United States Patent [19] Harris 51 Mar. 27, 1973 [54] DUAL ADJUSTMENT CYCLING TIMER 3,077,784 2/1963 Laviana at al "74/3052 [75] Inventor: John L. Harris Delafield, Wis 3,079,812 3/1963 Bross ..74/3.5 X

[73] Assignee: Deltrol Corp., Bellwood, Ill. Primary Examiner-Milton Kaufman [22] Filed: I Sept, 27, 1971 [57] ABSTRACT [7211 Appl' 183779 A continuous cycling timer in which the on and off periods are independently adjustable. A single motor 52 us. Cl. ..74/3.s2, 200/38 F drives two Spring return timing, discs through a Clutch 7 [51] Int. Cl. ..G05g 21/00 engaging one or the Other- The disengaged disc resets [58] Field of Search ..74/3.5, 3.52, 3.54; 200/38 R, its Swing POint when the other disc is engaged- 200/38 F 38 D The timer load switch and clutch are controlled by a single-actuator controlled by both timing discs. When the switch is closed, the on period timer operates. [56] References Cited When the switch is open, the off period timer UNITED STATES PATENTS p ra es. 2,905,778 9/1959 Fox et a] ..74/3.5 X 11 Claims, 4 Drawing Figures 2: 25 C) I 2 4 5 2.6 EX 8 3'5 2! l5 6 e l l0 A g l 6t7 {tq QQ NWI (5x f. l// d'\ g t I 50 l 89 l PATENTEUMARZHSH 722,294

24 INVENTOR.

3's /,4 KW

1 DUAL ADJUSTMENT CYCLING TIMER BACKGROUND OF THE INVENTION In many applications cycling timers are used for continuously cycling equipment on for a certain on period and off for a certain off period. Often it is necessary to vary the on period without affecting the off period or vice versa.

One method of accomplishing this is by the use of two separate automatic reset timers connected in tandem. One timer times the on period, and starts the off period timer. When this times out the off period, it restarts the on period timer. This arrangement provides for easily adjusting the on and off periods. However, it requires two completely independent and expensive timers and circuitry adding to the cost. This arrangement is expensive and also bulky.

Another method of providing independent adjustments for on and off periods is by using a reversible cycling timer. This timer cycles between two adjustable stops and operates a switch at the midpoint of the stroke. Setting one stop determines the on period and setting the other stop determines the off period. This arrangement requires a complex and expensive gear shift mechanism and the resulting unit is quite bulky.

BRIEF SUMMARY OF INVENTION The primary object of the present invention is the provision of a small, reliable and inexpensive cycling timer in which the on and off periods are independently timed so that one may be varied without affecting the I other.

reset by its return spring. At the end of the on period a spring is compressed and a first latch released, causing a switch operator to transfer a switch. This switch operator. also shifts the clutch gear which releases the on period timer and starts the off period timer. The on period timer resets and the switch operator is held in the on position by a second latch. This second latch is released by the off period timer at the end of the off period. The switch operator now drops to open the switch and restart the on period timer.

Adjustment of stops which determine the starting point of each timer provides for independent adjustment of the on and off periods. Other objects of the invention will appear from the following detailed description and appended claims.

BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a rear view of the timing mechanism looking through the transparent enclosure and with the motor removed. This figure shows the parts in the positions assumed at the beginning of an on period timing interval.

FIG. 2 is a view similar to FIG. 1 but showing the parts in the positions assumed at the beginning of an off period timing interval.

FIG. 3 is a side sectional view stretched out to show the arrangement of the various parts within the timer housing.

FIG. 4 is a sectional view showing the details of the switch operating and latch mechanism.

DETAILED DESCRIPTION OF INVENTION Referring to FIG. 1, reference character 1 indicates generally a housing which for illustrative purposes in cludes a transparent rear wall 2 which supports a switch generally indicated as 3. This switch may be of various configurations and is illustrated here as of the single pole single throw variety. This switch includes a combination contact and terminal bracket 4 mounted on the panel 2 and carrying a stationary contact 5. The switch also includes a combination switch blade and terminal bracket 6 also mounted on panel 2 and supporting an L-shaped switch blade 7 carrying a movable contact 8. The switch blade 7 is biased inwardly causing contact 8 to engage contact 5 with suitable contact pressure.

The switch blade 7 is actuated by a switch operator generally indicated as 10. As shown in FIG. 4, this switch operator is pivotally mounted on a stud 11 which is attached to the front plate 12 of the timer and is also supported by the rear wall 2. This switch operator includes a hub portion 13 and an elongated portion 14 extending generally parallel with the switch blade 7. (FIG. 1) This switch operator also includes'a latching surface 15 and a clutch operating surface 16. Also mounted on the stud 11 adjacent front plate 12 is a spring lever generally indicated as 18. This spring lever includes a front hub portion 19 and a rear hub portion 20 (FIG. 4), part of which fits into a recess formed in the switch operator 10. The spring lever 18 extends generally parallel with the switch operator l0 and includes a latch actuating surface 21 and a latching surface 22. The spring lever 18 also includes a driven surface 23 which is actuated by the timing mechanism.

The switch operator 10 and spring lever 18 are controlled by

latches

24 and 25 mounted on a stud 26 supported on the front plate 12. The latch 24 includes an extension 28 which extends into the path of the latching surface 15 on the switch operator 10. As shown in FIG. 4, the extension 28 on latch 24 extends rearwardly and the latching surface 15 on switch operator 10 extends forwardly providing for engagement of these two surfaces even though latch 24 and switc operator 10 are not in alignment.

The latching surface 22 of the spring lever is controlled by an extension 30 on latch 25. This extension 30 extends through the space provided in latch 24 forwardly into engagement with the-latching surface on the spring lever. The latch 24 is formed with an actuating surface 32 and the latch 25 is formed with an actuating surface 33. Latch 25 is biased counterclockwise as seen in FIG. 1 by a torsion spring 34 and latch 24 is biased in the same direction by a separate torsion spring 35.

The spring lever 18 is biased clockwise by means of a spring 37 which is of the torsion type and supported on the front hub portion 19 of the switch operator as shown in FIG. 4. One end of this spring 37 bears against the side wall of the enclosure and the other end bears against a stud 38 formed on the spring lever. Spring 37 therefore biases the spring lever 18 in a clockwise direction. The switch operator is biased clockwise relative to the spring lever by means of a spring 40 which is carried in part by the rear hub section 20 of the spring lever and a similar hub section on the switch operator. One end of the spring 40 bears against a stud 41 formed on the spring lever and the other end of spring 40 bears against a stud 42 formed on the switch operator 10. The spring 40 thus serves to bias the switch operator 10 counter-clockwise relative to the spring lever 18. However, counter-clockwise motion of the switch operator relative to the spring lever is limited by a stud 44 formed on the spring lever which is in the path of a extension 45 formed on the switch operator. When the stud 44 is engaged by extension 45, the spring 40 becomes inactive and the spring lever and switch operator are rotatable as a unit around the pivot stud 11. The arrangement of the switch operator, spring lever, and latches described above is shown and described in greater detail in my US. Pat. No. 3,489,015 dated Jan. I3, 1970.

The driven surface 23 of the spring lever is actuated by a drive pin 48 carried by a spring return timing gear 49. This timing gear 49 is carried on a shaft 50 which extends between the front plate 12 and the rear plate 2 and carries an adjusting knob 51 which may be manually set for the desired on period timing. The shaft 50 is rigidly attached to a setting gear 51 carrying a reset stop 52. The setting gear 51 is held in adjusted position by means of a locking pinion 53 carried on the front plate 12. A spring 54 adjacent the back plate 2 serves to press the shaft 50 forwardly causing the setting gear 51 to engage the locking pinion 53 for holding the setting gear in adjusted position. In order to change the timing, the user presses the knob 51 inwardly which releases the setting gear from the locking pinion allowing rotation of the setting gear to a different adjusted position. Release of the knob permits the spring 54 to return the setting gear back into engagement with the locking pinion for maintaining the shaft and setting gear in its new adjusted position. A reset spring 55 is mounted on a hub portion formed on the timing gear 49 between this gear and the setting gear 51. One end of the reset spring bears against the pin 48 on gear 49, and the other end of this spring bears against the reset stop pin 52 on the setting gear 51. It will be apparent that the reset spring 55 serves to bias the gear 49 in a counter-clockwise direction as seen in FIG. 1, thus causing the pin 48 to engage the adjustable reset stop 52.

The actuating surface 33 of latch 25 is engageable by an inturned portion 57 of a latch releasing lever 58. This le /er 58 is carried by a hub 59 mounted on the shaft 50 behind the reset gear 49. Lever 58 is arranged to float freely on this shaft. Lever 58 is actuated by an off period timing mechanism including a timing gear 60 carried on shaft 61. The shaft 61 is similar to shaft 50 and extends between the front plate 12 and the back plate 2. This shaft also supports a setting gear 62 carrying a reset stop 63 and engageable with a locking pinion 64 for maintaining the reset stop 63 in adjusted position. The shaft 61 carries an adjusting knob 65 which may be adjusted for the desired off period time. The timing gear 60 includes an actuating pin 66 and a reset spring 67 is provided for biasing the timing gear 60 clockwise as seen in FIG. 1 causing the gear pin 66 to be in engagement with the reset stop 63. As shown in FIG. 3, the lever 58 is off set so as to be engageable by v gear 72. This gear and pinion are supported on a stud 73 mounted on front plate 12. The timing gear 60 is similarly driven by a pinion 75 driven by a gear 76, the gear and pinion being supported on a stud 77 mounted on front plate 12.

The pinion 79 of the timer motor drives a floating gear 80 which is carried by a clutch lever 81 which is formed with a hub 82 mounted on a stud 83 carried by front plate 12. The stud 83 is located on the front plate 12 in alignment with the motor pinion 79 so that clutch lever 81 may be rocked without disturbing the driving relationship of pinion 79 with the gear 80. As shown more clearly in FIG. 3, the clutch lever 81 extends to the back of the timer adjacent plate 2 so as to locate the gear 80 in engaging relationship with the pinion 79. The clutch lever also includes an operating extension 85 which extends towards clutch operator 86. The gear 80 drives a clutch pinion 88 which extends between gear 72 which drives timing gear 49, and gear 76 which drives timing gear 60. As shown in FIG. 1 the pinion 88 and gears 72 and 76 are arranged so that the pinion can drive either only one or the other of the gears. A torsion type spring 89 is located on the hub 82, of clutch lever 81 and also on the mounting stud 83. One leg of this spring is suitably held by the front plate 12 and the other leg 90 bears against an arm 91 formed on the clutch lever. This biases this lever clockwise about pivot 83 thus bringing the clutch pinion 88 into engagement with the clutch gear 72.

The clutch operator 86 is mounted on a stud 93 carried by the case front 12. This clutch operator includes one lever portion 94 extending towards the switch operator and engageable by the clutch operating surface 16. The clutch operator also includes a second lever portion 95 which extends toward the lever portion 85 of the clutch operator 81.

OPERATION FIG. 1 shows the positions of the parts at the beginning of an on period. The end extension 45 of switch operator 10 is engagement with the lug 44 on the spring lever 18. The spring 40 located between the switch operator and spring lever is held preloaded while the spring 37 biases the spring lever clockwise causing its latching surface 22 to abut the top surface of latch 24. Due to lug 44 engaging extension 45, the switch operator 10 is moved to a position in which the latching surface 15 is below the latching surface 28 of latch 24. The operating pin 48 of gear- 49 is in engagement with the reset stop 52 due to the action of the resetspring 55. Due to the switch operator being in its inner position, it is clear of the switch blade 7 and the contacts 5 and 8 are engaged. In this position of the switch operator the clutch operating surface 16 is at its clockwise limit of movement and this has allowed the clutch operator 86 to disengage from the operating portion 85 of the clutch lever. This has permitted the spring 89 to rotate the clutch lever 81 clockwise bringing the clutch pinion 88 into engagement with the clutch gear 72. This same movement has disengaged the clutch pinion 88 from the clutch gear 76 and thus the timing gear 60 is in its reset position in which operating pin 66 engages the reset stop 63.

The timer motor 70 is now connected to drive gear 72 in a counter-clockwise direction which drives the timing means 49 clockwise. The operating pin 48 thus disengages its reset stop 52 and moves toward the driven surface 23 of the spring lever 18. As the end of the on period approaches, gear pin 48 engages the driven surface 23 and drives the spring lever 18 counter-clockwise as seen in FIG. 1, against the action of the spring lever return spring 37. This causes counter-clockwise rotation of the switch operator until the clearance is taken up between the latching surfaces 15 and 28. When these latching surfaces engage, further clockwise movement of the switch operator is restrained and continued movement of the spring lever now compresses the spring 40 in addition to compressing the return spring 37. Shortly before the end of the on period, the latching operating portion 21 of the spring lever engages the operating surface 32 of latch 24 and rocks latch 24 clockwise about its pivot, thus withdrawing the latching surface 28 from the end of latching surface of the switch operator. Simultaneously the latching surface 22 of the spring lever clears the upper end of the latch extension 30 of latch 25, and this latch moves into place under the latching surface 22.

At the termination of the on period, latching surface 28 of latch 24 releases the switch operator. This allows the spring to rotate this switch operator 10 counterclockwise to engage the switch blade 7 and separate the movable contact 8 from the stationary contact 5. This same motion of the switch operator by power previously stored in spring 40 also causes clockwise rotation of the clutch operator 86 due to the driving surface 16 of the switch operator engaging the driven surface 94 of the clutch operator. This brings the lever portion 95 of the clutch operator into engagement with the end of lever portion 85 on the clutch lever 81. This begins movement of the clutch pinion 88 from engagement with gear 72. This initial movement takes place with maximum leverage by the clutch operator for overcoming the forces tending to hold the gear and pinion in engagement. On continued motion of the switch operator and clutch operator, the leverage changes from one providing maximum force to one providing maximum movement and the parts assume the positions shown in FIG. 2. Here the end of lever portion 95 of clutch operator 86 is engaging the lever portion 85 of the clutch operator at a point providing maximum movement of the clutch lever per increment of movement of the switch operator 10. The clutch pinion 88 is disengaged from the gear 72 which has allowed the timing gear pin 48 to return to the reset stop 52 under the action of the reset spring 55. The spring lever 18 is now supported by latch 25, the latching surface 30 of which is under latching surface 22 of the spring lever. The spring lever thus is supported by the latch 25 and this maintains switch 3 open and the clutch pinion 88 in engagement with the clutch gear 76 of the off period timing means. The timer motor 70 now drives the off period timing gear 60 clockwise, causing the gear pin 66 to disengage from the reset stop 63. The timing of the off period has therefore begun. As the end of the off period approaches, the gear pin 66 engages the end 97 of the latch operating lever 58 causing it to rotate counter-clockwise from its stop 98 and causing the latch operating portion 57 to approach the driven surface 33 of latch 25. On continued motion the lever 58 causes clockwise rotation of latch 25 thus moving the latch toward disengaged position. At the end of the off period, latch 25 disengages the spring lever 18 and allows the spring lever to drop under the action of the return spring 37. The parts thus reassume the position shown in FIG. 1 in which the switch 3 is reclosed and the clutch lever is released, allowing its biasing spring 90 todisengage pinion 88 from gear 76 and reengage the gear 72. The disengagement of clutch pinion 88 from gear 76 allows the timing gear 60 to reset by the action of reset spring 67, causing pin 66 to engage reset stop 63.

From the foregoing it will be apparent that the invention provides two separate timing means, one for timing the on period and the other for timing the off period. The on period timing means is of the spring return reset variety and in operation stores power from the timer motor for providing instantaneous operation from on period timing to off period timing and back again. At the end of the on period timing, latch 24 releases the switch operator which simultaneously opens the switch and operates the clutch mechanism to disengage the on period timing means and engage the off period timing means. The off period timing means then times out and releases latch 25 which returns the mechanism back to on period timing, in which the switch is open and the clutching mechanism positioned to allow reset of the off period timing means and driving of the on period timing means.

It will further be apparent that the invention provides a clutch operating mechanism in which the mechanical advantage shifts during movement of the clutch gears,

initially providing maximum force for separating the gears under load and then providing maximum motion for disengaging the gears.

, It will further be apparent that the present invention provides for separate and independent adjustment of the on and off period timings, one never affecting the other. It also be apparent-that the transistion from on period timing to off period timing and vice versa is always instantaneous and requires no intermediate operation of the timer motor to perform.

While I have described a preferred form of the invention, it is obvious that many changes may be made without departing from the spirit and scope of the invention as defined in the following claims.

I claim:

1. In a time control, the combination of control means including a control device having a first position and a second position, a first spring return timing means, a second spring return timing means, drive means including a motor and selective clutch means mechanically connecting said motor to one or the other of said timing means, means operated by the first timing means for moving the control. device from its first position to its second position after a first predetermined period of time, means operated by the second timing means after a second predetermined period of time for moving the control device from its second position back to its first position, and means controlling the clutch means in a manner to drive the first timing means when the control device as in its first position, and to drive the second timing means when the control device is in its second position.

2. The combination recited in claim 1 in which a single actuator for the control device is controlled by both timing means, said single actuator also controlling the clutch means.

3. The combination recited in claim 1 including spring means wound by the motor and released by each timing means for actuating the control device and clutch means independently of immediate power from the motor.

4. The combination recited in claim 1 in which the clutch means includes a first gear driving the first spring return timing means, a second gear driving the second spring return timing means, and a movable pinion driven by the motor, said pinion selectively meshing with either the first gear or the second gear.

5. The combination recited in claim 2 including spring means wound by the timer motor and released by each timing means for actuating said single actuator independently of immediate power from the motor.

6. The combination recited in claim 2 in which the clutch means includes a first gear driving the first spring return timing means, a second gear driving the second spring return timing means, and a movable pinion driven by the motor, said pinion selectively meshing with either the first gear or the second gear.

7. In a time control, the combination of, a control device, an operator for said control device, said operator having a first position in which it holds the control device in a first position, said operator also having a second position in which it holds the control device in a second position, a first timing means, a second timing means, drive means including a motor and selective clutch means mechanically engaging said motor to one or the other of said timing means and causing the disengaged timing means to return to its starting position, spring means wound and then released by the first timing means after a predetermined first period of time for actuating said operator from its first position to its second position, means actuated by said operator for simultaneously shifting the clutch means to disengage the first timing means and engage the second timing means, means including latch means arranged to hold the operator its second position, means actuated by said second timing means for releasing the latch means after a predetermined second period of time, and spring means effective on release of the latch means for causing the operator to return from its second position to its first position, shifting the clutch means to disengage the second timing means and engage the first timing means.

8. The combination recited in claim 7 in which each of the timing means includes a return spring and a stop, each timing means moving by its return spring to a position against its stop when released by the clutch means.

9. The combination recited in claim 7 in which the clutch means includes a first gear driving the first timing means, a second gear driving the second timing means, and a movable pinion driven by the motor, said pinion selectively meshing either the first gear or the second gear,

10. In a timing device, the combination of, a timing element, drive means including a motor and clutch means for driving said timing element in one direction, said clutch means including a drive gear driven by the motor and a driven gear driven by the drive gear when the gears are in engagement, operating means for moving one of the gears relative to the other for separating said gears and thus disengaging the clutch means, said operating means comprising a power source and variable ratio motion transmitting means, said motion transmitting means being arranged to provide relatively high mechanical advantage at the beginning of the clutch disengagement movement and relatively low mechanical advantage thereafter.

1 1. The combination recited in claim 10 in which the variable ratio motion transmitting means includes two levers having spaced pivots and arranged to contact at different points during the clutch disengaging movement.

Claims

1. In a time control, the combination of control means including a control device having a first position and a second position, a first spring return timing means, a second spring return timing means, drive means including a motor and selective clutch means mechanically connecting said motor to one or the other of said timing means, means operated by the first timing means for moving the control device from its first position to its second position after a first predetermined period of time, means operated by the second timing means after a second predetermined period of time for moving the control device from its second position back to its first position, and means controlling the clutch means in a manner to drive the first timing means when the control device as in its first position, and to drive the second timing means when the control device is in its second position.

9. The combination recited in claim 7 in which the clutch means includes a first gear driving the first timing means, a sEcond gear driving the second timing means, and a movable pinion driven by the motor, said pinion selectively meshing either the first gear or the second gear.

11. The combination recited in claim 10 in which the variable ratio motion transmitting means includes two levers having spaced pivots and arranged to contact at different points during the clutch disengaging movement.