US2487295A - Synchronized time-controlled driving mechanism - Google Patents

Description

A. B. BENSON 2,487,295

SYNCHRONIZED TIME-CONTROLLED DRIVING MECHANISM Nov. 8, 1949 Filed Aug. 14, 1947 N v n d-HAM Ria -Mm AGENT Patented Nov. 8, 1949 UNITED STATES PATENT OFFICE SYNCHRONIZED TIME-CONTROLLED DRIVING MECHANISM Application August 14, 1947, Serial No. 768,699

7 Claims. (01. 318266) The improved synchronized time-controlled driving mechanism comprising the present invention is primarily adapted for use in connection with the driving operations of a program device of the type shown and described in a copending application of R. B. Johnson, Serial No. 768,142, filed August i2, 194?. The driving mechanism of the present invention may also be found useful for controlling the operation of other types of program units of the type employed in connection with time recording systems, or, in fact, it may, with or without modification, be employed as a one revolution or fractional revolution driving mechanism for controlling the rotational movements of a driven member regardless of its nature or of the use to which the same may be put.

Heretoiore most impulse-operated program de- I vices are periodically actuated from master clock impulses that are derived from the master clock of a time recording system and which are the same impulses that ordinarily are employed for controllin the operation of one or more secondary clocks. Generally such impulses are applied to the energization of an electrom'agnet which, operating as a solenoid, serves to index a ratchet or other suitable mechanism for the direct application of driving torque or power to the program device. An example of such a time recording system may be had by reference to the patent to Bryce, No. 1,687,491, dated October 16, 1928 for a Synchronizing clock.

The present impulse driving mechanism is deemed to be advantageous over such conventional solenoid-operated driving mechanisms as have briefly been outlined above in that, although it receives its initiating impulses from the master clock of a conventional time recording system, it employs an electric motor for actual driving purposes. This motor, operating through a gear reduction device, is capable of a more effective, positive and smoother drive as well as a more silent one than is possible when conventional solenoid driving mechanism is employed. Additionally, a far more powerful drive is obtained inasmuch as with solenoid-operated mechanism the power applied to the driven member or element come readily apparent as the following description ensues.

The accompanying drawing discloses by way of example the principle of the invention and the best mode which has been contemplated of applying that principle.

In the drawing the figure is a bottom plan view, partly section, of an impulse-cperated driving mechanism constructed in accordance with the principles of the present invention d showing schematically the electrical circuits t srefor.

Referring now to the drawing in detail, the apparatus involves in its general organization a framework which is designated in its entirety at ill and which includes a base or casting H and a top plate I 2, the latter being spaced from the base and being connected thereto by means of spacing bolts 13. The casting II has bolted or otherwise secured thereto as at I4 an electric motor M which is adapted to periodically be energized to drive an output shaft l5 suitably journalled in the framework I0 through a train of driving mechanism the nature and function of which will become clear presently.

It will be understood that the output shaft I! may be coupled and utilized in any suitable manner to apply driving torque or power to the operative instrumentalities of a program device of the type shown and described in the above mentioned application of R. B. Johnson, and in such an instance it is coupled at a one-to-one ratio by suit-.

able gearing (not shown herein but disclosed in the application) to the driving shaft of the program device which it is desired to index one tenth of a revolution at minute intervals of time as well as to maintain it in :ynchronism with clock time as represented by the master clock of a time recording system of the type shown in the above mentioned patent to Bryce.

The motor M is provided with a motor shaft I 6 which operates through a conventional flexible coupling assembly designated in its entirety at H to drive a worm shaft l'8 which is suitably journalled as at H in side members 20 formed on the casting II. The worm shaft I8 is formed with a worm 22 thereon which meshes with a worm gear 24 mounted on a shaft 26 suitably journalled in the framework Ill. The shaft 26 carries a spur gear 28 which meshes with a larger gear 30 mounted on the output shaft IS.

The motor M is adapted to receive periodic impulses or applications of current from a source S of electric current, these impulses being initiated under the control of an electromagnet 32 suitably supported on the casting H. The magenemas net 32, in turn, is adapted to receive normal energizing impulses at regular minute intervals throughout the course of each hour, providing the position of the various instrumentalities of the program device, which derive their motion from the movements of the output shaft i5, agree with the clock time as represented by the .master clock of the time recording system. If these instrumentalities are fast as regards clock time, i. e. if they are in excess of clock time, means are provided for applying rapid impulses to the magnet 32 during a selected synchronizing period during each hour. On the other hand, if they are slow as regards clock time, means are provided for withholding the application of normal impulses during the selected synchronizing period.

The means whereby such rapid impulses are applied to the magnet 32 or whereby all impulses are withheld from the magnet during the synchronizing period forms no part of the present invention and reference may be had to the above mentioned patent to Bryce for a full disclosure of how normal and rapid impulses are conducted to a magnet similar to the magnet 32 or how these impulses are withheld. For purposes of illustration herein it is deemed sufilcient to state that the magnet 32 is electrically connected through a two-way contact group 34, including contacts 36 and 38, with the electrical system of the master clock. The contacts 36 and 38 are adapted to be selectively closed by the operation of a rotary synchronizing cam 50 which derives its motion from the output shaft it through a pair of meshing gears t2 and M which operate to move or index the cam (it at one minute intervals throughout a full revolution during each hour.

The synchronizing cam M3 is provided with a low portion 66 and a high portion 38, which portions cooperate with a finger 56 associated with the contact group 36 to shift the position of the contact group in accordance with the principles set forth in the Bryce patent to permit normal impulses to be applied to the magnet 32 during each hour, to apply rapid impulses to the magnet during the synchronizing period, or to withhold all impulses from the magnet during the synchronizing period as occasion demands.

If the condition of the instrumentalities of the program device is such that it is on time and in agreement with the master clock, the finger 5G is on the center of the high portion of the synchronizing cam Aid and the contacts 38 are closed and are in condition to transmit normal minute impulses which issue from the master clock system over the wire A to the magnet 32'.

If the condition of the instrumentalities associated with the program device is assumed to be fast with respect to clock time, the finger 56 will rest on the low portion of the cam with the contacts 3t closed and with the contacts 38 open. As set forth in the Bryce patent, from the beginning to the end of the synchronizing period only normal impulses are applied over the wire A. Therefore the magnet 32 will receive no further normal impulses and will remain deenergized until the end of the synchronizing period.

If the condition of the program instrumentalities is assumed to be slow, the finger 58 will have just passed the rise of the cam 50, thus reclosing the contacts 38 and opening the contacts 36. The magnet 32 will therefore receive normal impulses over the wire A during the major portion of the synchronizing period. However, as explained in the Bryce patent, just after the fiftyninth minute of the hour a series of rapid impulses are transmitted over the wire A to the magnet 32 and these impulses serve to bring the program device rapidly up to agreement with the master clock after which time the contacts 88 become open to stop the supply of rapid impulses to the magnet. It will be understood that when the program instrumentalities are in agreement with the master clock the contacts 38 will be open at the fifty-ninth minute of the hour to prevent fast impulses from the wire A from affecting the magnet 32. During the non-synchronizing period of each hour normal impulses are applied to both the wires A and B and' consequently during this time the condition of the contacts 36 and 38 is immaterial.

The electromagnet 32 is supported from the casting l I by means of a yoke 52 to which there is secured a leaf spring 54 having attached to its outer end as at 56 the magnet armature 58. The armature is provided with a slot 60 therein which receives one end of a contact making and breaking assembly including a pair of plates 6i. and 84, the two plates being welded or-otherwise secured together. The assembly 62, 64, serves to control the opening and closing movements of a pair of normally open contacts 86 included in a contact assembly 66 mounted on the casting H. The contacts 66 are included in a motor circuit and serve to periodically supply current from a source S to the electric motor M.

The plate assembly 82, 64 is guided near the magnet end between a pair of studs it and its clockwise swinging movement is limited by means of a stop or abutment 72 in the form of a screw. The upper end of the plate 86 is designed for cooperation with a finger dd associated with the contact group 68 in a manner that will be set forth presently.

The shaft 26 has mounted thereon a cam memher it the periphery of which cooperates with one end of a cam follower or trip plate 78. The other end of the follower it normally occupies a position immediately beyond the outer end of the plate 62 and in engagement with the side of the plate 64. A leaf spring 8i); is secured as at 82 to the casting ii and has a tongue-and-slot connection 86 with a medial portion of the follower lld, the arrangement being such that the follower is normally urged in a counter-clockwise direction against the surface of the plate 5 3 to the limit of extent permitted by the follower it.

The plate assembly 62, 66 is normally biased against the end of the follower it by means of a spring 86 while the follower is guided between apair of studs 88.

In the normal position of the apparatus when the magnet 32 is deenergized as shown in the drawing, the extreme outer end of the plate 6 occupies a position beyond and clear of the end of the contact finger iii and as a consequence the contacts at assume their normally open position. At the same time the extreme end of the follower l8 abuts against the side of the plate 62. When the magnet receives an impulse of current from either the line A or the line B emanating from the master clock of the time recording system, the armature 58 is attracted and the entire plate assembly 62, as is drawn in the direction of the magnet until the end of the plate 82 clears the end of the follower l8 and the end of the plate 64 is moved to one side of the end of the finger 38. At this point the plate assembly is drawn in a clockwise direction as viewed in the drawing to the limit permitted by the abutment" so that the end of the plate 84 registers with the end of the contact finger 14.

Upon termination of the impulse which is applied to the magnet 32, the magnet will be deenergized and the armature 58, under the infiuence of the leaf spring 54, will move outwardly, thus moving the plate assembly 62, 64 axially and closing the contacts 66, thus completing the motor circuit and supplying current from the source S to the motor M.

Energization of the motor M-will cause the train of driving mechanism previously described and including the worm 22, gear 24 and shaft 28 to rotate the cam 18. Rotation of the cam I5 will cause the follower to ride outwardly on the sprial periphery of the cam, thus drawing the cam follower 18 to the right and allowing the end thereof to clear the end of the plate 62. When such clearance is established the follower will be abruptly tilted through a small counterclockwise movelnent by virtue of the leverage applied thereto by the leaf spring 80 so that the end of the follower will bear against the side of the plate 62. When the end of the follower encounters the drop-off portion of the cam 16, the follower will be moved to the left and the plate assembly 52, 64 will be forcibly moved in a counter-clockwise direction so that the upper end of the plate 64 will clear the end of the contact finer 14 and allow the contacts 66 to open. The supply of current to the motor will thus be interrupted and the parts will have been restored to their initial position to await the next application of current to the magnet 32.

During the time that the shaft 26 and'cam l6 perform a complete revolution, the gear' 30 and output shaft I! will perform one-tenth of a revolution and the arrangement of the gearing 28, 30 is such that this will be the case.

It will be remembered that the output drive to the program device shown and described in the above mentioned Johnson application is required to perform an indexing operation of onetenth of a revolution each minute so that the drive shaft of the device will be rotated once during each ten minute interval of time. The present driving mechanism has been designed to accommodate such a program device but it will be distinctly understood that, by suitable modification of gear ratios and the, like, the present driving mechanism may be adapted for use in the driving of various program or other instrumentalities which require a fractional or a full revolution impulse drive.

While there have been shown and described and pointed out the fundamental novel features of the invention as applied to a single modification, it will be understood that various omissions and substitutions and changes in the form and details of the device illustrated and in its operation may be made by those skilled in the art without departing from the spirit of the invention. It is the intention therefore to be limited only as indicated by the scope of the following claims.

What is claimed is:

1. An electrical impulse-controlled driving mechanism comprising in combination an output shaft, an electric motor, means operatively connecting the motor and shaft in driving relationship, an electric circuit for said motor, a source of current supply for said circuit, a pair of normally open contacts disposed in said circult and having an operating finger associated ture movable from a retracted position when the magnet is energized to an advanced position when the magnet is deenergized. means normally maintaining the armature in its advanced position, a contact-closing arm carried by the armature and movable bodily therewith. said contact-closing arm normally occupying a position out of registry with said operating finger, means operable upon energization of the magnet for moving said arm into registry with said finger whereby upon deenergization of the magnet the arm is caused to engage sald'finger to close said contacts and energize the motor, means operable under the driving control of said motor for restoring said arm to its position of non-registry with said-finger, and means for supplying periodic impulses of energizing current to said magnet.

2. An electrical impulse-controlled driving mechanism comprising in combination an output shaft, an electric motor, means operatively connecting the motor and shaft in driving relationship, an electric circuit for said motor, a source of energizing current for said circuit, a pair of normally open contacts disposed in said circuit and having an operating finger associated therewith, an electromagnet having an armature movable from a retracted position when the magnet is energized to an advanced position when the magnet is deenergized, means normally maintaining the armature in its advanced position, a contact-closing arm carried by the armature and movable therewith bodily, said contact-closing arm normally occupying a position out of registry with said operating finger, means operable upon energization of the magnet for moving said arm into registry with said finger whereby upon deenergization of the magnet the arm is caused to engage said finger and close said contacts and energize the motor, cam means operable under the driving control of said motor for restoring said arm to its position of non-registry with said finger, and means for supplying periodic impulses of energizing current to said magnet.

3. An electrical impulse-controlled driving mechanism comprising in combination an output shaft, an electric motor, means operatively connecting the motor and shaft in driving relationship, an electrical circuit for said motor, a source of current supply therefor, a pair of normally open contacts disposed in said circuit and having an operating finger associated therewith, an electromagnet having an armature movable from a retracted position when the magnet is energized to an advanced position when the magnet is deenergized, means normally maintaining the armature in its advanced position, a contactclosing arm pivotally mounted on the armature and movable bodily therewith and capable of independent tilting movements relative thereto, said contact-closing arm normally occupying a position out of registry with said operating finger, means operable upon energization of the magnet for tilting said arm into a position of registry with said finger whereby upon deenergization of the magnet the arm is caused to engage said finger to close said contacts and energize the motor, means operable under the driving control of said motor for restoring said arm to its position of non-registry with said finger, and means for supplying periodic impulses of energizing current to said magnet.

4, An electrical impulse-controlled driving mechanism comprising in combination an output shaft, an electric motor, means operatively connecting said motor and shaft in driving relationship, an electrical circuit for said motor, a source of current supply therefor, a pair of normally open contacts disposed in said circuit and having an operating finger associated therewith, an electromagnet having an armature movable from a retracted position when the magnet is energized to an advanced position when the magnet is deenergized, means normally maintaining the armature in its advanced position, a contactclosing arm pivotally mounted on the armature and bodily movable therewith and capable of independent tilting movements relative thereto, said contact-closing arm normally occupying a position out of registry with said operating finger, means operable upon energization of the magnet for tilting said arm into a position of registry with said finger whereby upon deenergization of the magnet the arm is caused to engage said finger to close said contacts and energize the motor, a rotatable cam, means operatively connecting said motor and cam in driving relationship, a cam follower cooperating with said cam, means operatively connecting said follower and contact-closing arm, said follower being operable upon actuation thereof by said cam to restore said arm to its position of non-registry with said finger, and means for supplying periodic impulses of energizing current to said magnet. I

5. An electrical impulse controlled driving mechanism comprising an electric motorhaving a drive shaft, an electric circuit for said motor, a driven shaft, means operatively connecting the drive shaft and driven shaft in driving relation- I ship, a cam on said driven shaft, a pair of northe contract operating finger, said contact-closing arm being movable bodily with the armature when the magnet is energized to a position wherein said shoulder is withdrawn from registry and engagement with the follower to permit the arm to move into registry with said contact-operating finger whereby upon deenergization of the magnet said arm will engage said finger and close said contacts to energize the motor, said follower being operable upon rotation of said cam to move into register with said shoulder and to thereafter engage the latter and move the end of the contact-closing arm out of registry with said finger and thus permit said contacts to be re-,

opened to deenergize the motor, and means for supplying periodic impulses of energizing current to said magnet.

8. An electrical impulse-controlled driving mechanism as set forth in claim 5 in which the connecting means between the drive shaft and the drivenshaft comprises a worm and a worm gear presenting a high gear reduction ratio whereby when said motor is deenergized, overdriving of the driven shaft will be prevented.

'7. An electrical impulse-controlled driving mechanism comprising an electric motor having a drive shaft, an electric circuit for said motor, a driven shaft, worm and gear reduction driving means connecting the drive shaft and driven shaft in driving relationship,'a cam on said driven shaft, a pair of normally open contacts disposed in said motor circuit and having an operating finger associated therewith, an electromagnet having an armature movable from a retracted lowered position when the magnet is energized to an advanced elevated position when the magnet is deenergized, a contact closing arm pivoted to said armature, a cam follower for said cam, one end of which normally bears against the latter and the free end of which projects forwardly away from said cam, said contact closing arm being provided with a shoulder thereon against which the free end of said cam follower normally bears to maintain the end of the contact closing arm out of registry with the contact operating finger, said contact closing arm being movable bodily with the armature when the magnet is energized to a position wherein said shoulder is withdrawn from registry and engagement with the follower and is positoned in registry with said contact operating finger with said shoulder underlying the free end of said cam follower whereby upon deenergization of the magnet the arm will engage said finger and close said contacts to energize the motor and the shoulder will engage the free end of said follower and tilt the same upwardly, said follower being operable upon rotation of said cam to again move into register with said shoulder and to thereafter engage the latter and move the end of the contact closing arm out of registry with said finger,'thus permitting said contacts to reopen and deenergize the motor, and means for supplying periodic impulses of energizing current to said magnet.

ALFRED B. BENSON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,290,718 Crane Jan. 7, 1919 1,935,017 Capre Nov. 14, 1933

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