US2902554A - Timer mechanism - Google Patents

Description

p 1, 1959 H. A. sE-ELE 2,902,554

TIMER MECHANISM Original Filed Aug. 27. 1956 Q INVENTOR.

QJTM ATTORNEY United States Patent f TllVIER IVIECHANISM Harold A. Seele, Los Angeles, Calif.

Original application August 27,1956, Serial No. 606,258. Divided and this application June 28, 1957, Serial No. 668,789

'6 Claims. (Cl. 200-38) This invention relates to a timer mechanism and is a division of my pending application, Serial No. 606,258, filed August 27, 1956.

In said application, there is disclosed automatic control means for sprinkler systems that operates in an efiicient manner because the same is not merely timed to operate periodically, but rather according to sub-soil moisturea condition that may vary according to drainage characteristics of the soil and evaporative effects of the sun and variable weather conditions. The system shown in said application embodies an automatic timer mechanism that, while time-operated,-is under control of moisture-sensing means.

An object of the present invention is to provide timecontrolled mechanism of the character referred to for enabling pre-setting the time of operation of watering means so the same may function at the time and for the period desired.

A more general object of the invention is to provide a timer mechanism to control the operation of a piece of equipment, for instance, a valve, switch, etc., and to institute and stop operation of such piece of equipment under the general control of a time motor.

The invention also has for its objects to provide such means that are positive in operation, convenient in use, easily installed in a working position and easily disconnected therefrom, economical of manufacture, relatively simple, and of general superiority and serviceability.

The invention also comprises novel details of construction and novel combinations and arrangements of parts, which will more fully appear in the course of the following description. the following description merely describes, one embodiment of the present invention, which is given by way of illustration or example only.

In the drawing, like reference characters designate similar parts in the several views.

Fig. l is an elevational view, with the mounting means in cross-section, of a time-controlled mechanism according to the present invention.

Fig. 2 is a sectional view, with parts broken, of the mechanism shown in Fig. 1, the view being taken on a plane rearward of the front of Fig. 1.

Fig. 3 is a fragmentary sectional view, taken on a plane rearward of the front of Fig. 2.

Fig. 4 is an enlarged cross-sectional view as taken approximately on the line 44 of Fig. 2.

Fig. 5 is an enlarged cross-sectional view as taken approximately on the line 55 of Fig. 3.

The present timer mechanism is shown as comprising a clock motor and switching means 11 under continuous control of said motor.

The clock motor 10 is generally conventional and, in this instance, may be electrically operated, although spring or other power operation may be used. In any case, said clock has two concentric output shafts, the fast shaft 12 making one revolution per hour and the slow shaft or sleeve .13 making one revolution per day or twenty-four Patented Sept. 1, 1959 hours. These relative rates of rotation are exemplary and may be varied as desired. The back plate 14 of the clock is used for mounting the switch means 11, the shaft 12 and sleeve 13 extending through said plate (Fig. 4). Said switching means 11 is operated by said fast and slow shafts.

Sleeve 13 carries a flanged disc 15 on the rear face of which is provided a cam 16, it being clear that said cam makes one revolution around the axis of sleeve 13 in each twenty-four hours. The flange 17 of said disc, on its rear face, is provided with members 18 indicative of hours, the same being readable through a hole 19 provided in a dielectric back plate 20 of said means 11. The location of the cam 16 can be determined by reading of the hour as seen through said hole 19.

A bracket 21, fastened at one end 22 to plate 14 and having its other end 23 apertured to pass shaft 12, carries a rise 24 that is engaged by cam 16 once every twentyfour hours. Said bracket being resilient, the same is deflected rearward by cam 16.

On the rearward side of bracket 21, and slidably mounted on shaft 12 but keyed thereto to rotate with the shaft, is provided a clutch disc 25, the same being provided with a rearwardly directed clutch tooth 26. Disc 25 is biased forward by a spring 27, said spring yielding to the action of cam 16 to press the clutch disc rearwardly.

A flanged hub 28 is provided, the same being an aligned extension of shaft 12 with which it has an aligning connection 29.

On said hub 28 is rotatably carried a plate 30 which is formed with a forwardly directed clutch tooth 31 that is rearwardly clear of tooth 26 except when the cam 16 presses the bracket 21 rearwardly. When the clutch teeth are engaged, as shown in Fig. 2, rotation of clutch disc 25 is imparted to plate 30. Said latter plate is provided with one or more rearwardly extending legs 32 that space said However, the drawing merely shows and plate from a disc 33 mounted on the forward face of the back plate 20. An additional leg is formed as a cam 34.

In the space provided above, is disposed a contact arm 35 that is resiliently connected to plate 30 by a torsion spring 36. Said arm is provided with a resilient lock .tooth 37 that has successive abutting engagement with abutments 38 that are defined by holes formed in disc 33. Said arm 35 is provided with a contact end 39 and inward of said end, the arm carries a bridging contact 40, the same being insulated from the arm as by a block 41.

It will be realized that spring 36 also biases arm 35 in a direction to engage tooth 37 with one of the abutments 38 and the rotation of plate 30 first builds up torsion in spring 36 and then, when said torsion becomes great enough, imparts rapid or sudden rotative movement of the arm 35.

In connection with the contact end 39 of arm 35, there is provided an arcuate contact bar 42 which is associated with a series of arcuately spaced contacts 43 that overstand said bar so that arm end 39 may assume a position bridging said bar and one of the contacts, as shown in Fig. 2.

In connection with bridging contact 40, there is provided a second arcuate contact bar 44 with which is associated a series of arcuately spaced contacts 45. Said contacts 45 are so located that, when arm end 39 is disposed in bridging engagement between bar 42 and a contact 43, the bridging contact 40 will bridge across bar 44 and a contact 45.

At hourly intervals, or such other intervals as may be desired, clutch tooth 26 Will pass by clutch tooth 31, and only when the cam 16 is in engagement with bracket rise 24 will said bracket be deflected to engage the clutch teeth to institute building up of torsion in spring 36. When said torsion is high enough, the arm 35 will be moved from one position to the next, bridging between bar 42 and contact 43, on the one hand, and bar 44 and contacts 45 on the other. It will be realized, of course, that spring 36 is ineffective until cam 34 engages the resilient lock tooth 37 (Fig. to withdraw the same from engagement with an abutment 38.

After cam 16 leaves the rise 24, the clutch is disengaged. However, the electrical contacts made between bar 42 and its contacts 43 and bar 4'4and its'contacts 45 are retained.

The circumferential extent ofcam 16, together with the effective width of rise 24, controls the circuit-closing operation of the clutch. Thus, this extent may be equal to one hour of the rotation of cam 16, thereby holding the clutch engaged during one revolution of clutch plate 35, so that successive circuits may be closed by the bridging contact end 39 while successive circuits may be made by contact 40.

The arm 35 is located by the lock tooth 37 engaging an abutment 38 and said armretains this position until spring 36 is tensioned. Then, cam 34 withdraws said tooth, allowing the spring to snap the arm 35 to the next position, which is again locked by tooth 37. The rapidity of the break and make will be obvious.

The circumferential extent of cam 16 may be increased so that the clutch teeth 26 and 31 will retain engagement for more than one hour, i.e., for two or more revolutions of the hour or fast shaft.

A knob 46 on the end of an extension 47 of flanged hub 28 may be used as a manual control for overriding the clock-driven shaft 12. Thus, the switch means may be manually controlled, as desired.

While the foregoing has illustrated and described what I now contemplate to be the best mode of carrying out my invention, the construction is, of course, subject to modification without departing from the spirit and scope of the invention. It is, therefore, not desired to restrict the invention to the particular form of construction illustrated and described, but to cover all modifications that may fall within the scope of the appended claims.

Having thus described my invention, what I claim and desire to secure by Letters Patent is:

1. A timing device comprising a clock having a fast shaft and a concentric slow shaft, electrical switch means with an operative connection to the fast shaft, a clutch with coupling means connected to the slow shaft and interposed in the connection for operating the switch means, a cam operated by the slow shaft, a cam operated member constituting the means to couple the clutch, means inducing an intermittent operation of the switch means, said clutch, when coupled, operating said latter means once for each revolution of the fast shaft, the means inducing the intermittent operation of the switch means including a rotational contactor, a latch, and a spring-biased member controlled by the clutch to both apply the biasing force of the spring on the contactor and to sequentially release the latch.

2. A timing device according to claim 1 in which the relative rotation of the fast shaft and the cam is such that the clutch is maintained coupled for more than one revolution of the fast shaft.

3. A timing device according to claim 1 in which the relative rotation of the fast shaft and the cam is such that the clutch is maintained coupled for at least two revolutions of the fast shaft.

4. A timing device comprising a clock having a fast shaft and a slow shaft, a clutch disc keyed to the fast shaft to rotate therewith, slidable thereon longitudinally of the shaft, a clutch operated member connectable with the clutch disc upon movement of the latter, a cam on the slow shaft, a resiliently mounted clutch disc-engaging arm in the path of said cam to be deflected thereby, once for each revolution of the slow shaft adapted to move the clutch disc to engaging position, the width of the cam in relation to the width of the clutch disc-engaging arm determining the duration of the clutch engagement, a movable contact arm, stationary contacts electrically cooperable therewith for opening and closing electrical contacts, a spring inter-connecting the contact arm and the driven clutch member, and means for resisting motion of the contact arm to produce snap action from the force of the spring.

5. A timing device as in claim 4 in which detents are provided for locking the contact arm in a plurality of different angular positions, thereby resisting motion of the contact arm to cause spring force to be built up by rotation of the fast shaft, and a detent retractor carried by the fast shaft for periodically releasing the contact arm to effect contact opening and closing by snap action.

6. A timing device as in claim 4 wherein the ratio between speeds of revolution of the slow shaft and the fast shaft is smaller than the ratio between the width of the cam on the slow shaft and the peripheral distance around the slow shaft at the radius of said cam, whereby the clutch is maintained coupled for more than one revolution of the fast shaft.

References Cited in the file of this patent UNiTED STATES PATENTS 1,533,677 Warren Apr. 14, 1925 2,024,162 Haynes Dec. 17, 1935 2,035,712 Luoma Mar. 31, 1936 2,300,020 Smith Oct. 27, 1942 2,745,918 Stewart May 15, 1956

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