US 2300576 A
Description (OCR text may contain errors)
Nov. 3, 1942. N. E. KLEIN LOOP-AUTOMATIC AND MANUAL DRIVE Filed Jan. 6, 1940 I NV EN TOR.
WORM/7A 5. A1 E/(V ATTOREEY.
Patented Nov. 3, 1942 LOOP-AUTOMATIC AND MANUAL DRIVE Norman E. Klein, Chicago, 111., assignor, by mesne assignments, to International Telephone 8: Radio Manufacturing Corporation, a corporation of Delaware Application January 6, 1940, Serial No. 312,666
My invention relates to automatically driven devices provided with auxiliary manual control,
and more specifically to rotating loop antennas provided with automatic and manual driving means.
It is frequently desirable to include with devices that are automatically driven a manual control for purposes of fine adjustment and the setting of a zero,.or a reference point. If the manual control is rigidly connected to the automatic driving means, the manual control must be in operation at all times. This practice results in considerable wear and unnecessary motion.
An object of my invention 'is to provide a manual control that is not necessarily in operation when the automatic driving means is in use.
With any arrangement that allows the manual control to remain inoperative when the automatic driving is used, if there is an indicator associated with the manual control, some provision must be made for maintaining the indicator in step with the driven member. A common method of making the manual controlindependent of the automatic driven uses a clutch arrangement, but a clutch arrangement usually 'allows the manual control to operate during any portion of the rotating member cycle.
A further object of my invention is to allow the manual control to operate only at a predetermined point in the rotating member cycle.
' A further object of my invention is to mini- 'mize errors introduced by back lash and play in the interconnecting driving means.
In a preferred structural embodiment of my invention a rotatable loop antenna is driven by a motor, and a cam and a relay are adapted to stop the motor at a. predetermined point in its rotation. The motor drives the rotatable loop through a planetary gearing system and a manual control is connected to the planetary gearing system in such a manner that the manual control is not necessarily operative when the motor is driving the rotatable loop.
My invention will be more clearly understood by the description in connection with the attached drawing, the single figure of which is an embodiment of my invention.
In the figure the motor I is provided with a split ring commutator 2, two slip rings 3 and 4, brushes 5, an armature winding 8, a series winding 1, and a shunt or series winding 8. The motor i drives the rotatable loop shaft 8 by a shaft I0, pinion II and the planetary gearing system containing planetary gear l2 and ring gear i3.
When it is desired to automatically drive the rotatable loop, switch 2| is closed to the motor position. In this position the relay 22 is not energized and the relay switch 23 is in a down position. When switch 23 is in the down position, series field I and armature 6 are connected in series through the split commutator 2, and winding 8 is a shunt field, the motor thus acting as a compound motor. With the inotor in operation the ring gear I3 is held stationary by the worm 20, and the loop is rotated by the pinion ii and the planetary gear l2 associated'with the support 24.
1!, when it is desired to change over to manual control, the motor were allowed to stop at any random position, there would be no direct indication between the indicator H and the position of the loop 9. It is therefore desirable, if not necessary,'to stop the loop at a predetermined position so that the loop bears a fixed relation to the pointer on the indicator ll. To do this a cam 25 is provided which, due to the gears 26, rotates at the same speed as the loop. When the switch 2| is closed to the side labeled Manual, the motor i operates at a reduced speeddue to the insertion of a resistor 28 in series with the motor and the battery source 29. The loop continues to rotate after the switch is closed to the Manual side until cam 25 closes the contacts 21 the slip ring action, the motor armature will no longer rotate but will assume a fixed position determined by the flux action of the windings B and i. It may be seen, therefore, that the rotatable loop 9 will always stop in a position determined by the previous manual control adjustment.
Because of the magnetic action between the coils 8 and 6, the pinion Ii is held in a fixed position. The manual control apparatus can now be used to rotate the loop shaft 9 through the agency of'gears l8 and I8, comprising a crank l5, reduction gear box I6 and flexible cable l1, worm 20, ring gear l3, and planetary gear l2.
In the preferred embodiment of my invention the rotation of crank I5 is geared down by means of the gear box It and geared up by means of gears l8 and it. This arrangement has the further advantage that play and back lash in the cable I1 is minimized since, due to the gearing ratios, the amount of play that is normally present in such a cable, will cause negligible effect at either the indicator ll or the loop antenna.
While I have shown particular gear ratios between the driven and driving parts, any desired gear ratio may be utilized. However, it has been found that gearing in the direction that I have shown, is preferable both for constructional reasons and accuracy of setting.
With suitable switching arrangements, the compound motor shown may be substituted for by either a series motor or a shunt motor. Due to its operating characteristics, however, the compound motor arrangement shown is preferred While I have described particular embodiments of my invention for purposes of illustration, it will be understood that various adaptations and modifications thereof may be made within the spirit of the invention as set forth in the appended claims.
What I claim is:
1. An arrangement for automatically and manually controlling a rotatable loop antenna comprising, a motor comprising an armature winding, a split commutator ring and slip rings connected thereto, and a field winding, a shaft driven by said motor, a planetary gearing system comprising planetary gears, a support attached thereto, and a ring gear in engagement therewith, a pinion attached to said shaft for driving said planetary gears, a rotatable loop shaft attached to said support, a manual drive comprising a crank, an indicator controlled by said crank, gears driven by said crank, a shaft driven by said gears, further gears driven by said shaft, and a worm gear in engagement with said ring gear and driven by said further gears, and means for stopping the first mentioned shaft in a single predetermined position comprising a cam driven by said first-mentioned shaft, contacts operated by said cam, a relay coil connected to said contacts, a source of energy for said motor, switching means for connecting said source to said motor only or to said motor and in series with said relay coil and said contacts depending upon whether automatic or manual control is desired, and switching means actuated by said relay cell for connecting said field winding in shunt and said armature winding in series with said split commutator ring when said relay coil is inoperative and for connecting said field winding and said armature winding in series with said slip rings when said relay coil is operative.
2. An arrangement for automatically and manually controlling a rotatable member comprising a manual drive shaft, a motor drive shaft. motion-combining coupling means between said two drive shafts and said rotatable member for transmitting to said member a combined rotary motion made up of a first component proportional to the rotation of said manual drive shaft plus a second component proportional to the rotation of said motor drive shaft, an indicator coupled to said manual drive shaft, whereby said indicator may be driven from said manual drive shaft and may indicate said first component of motion of said rotary member, control means driven by said motor drive shaft and cyclically producing a control condition at a rate corresponding to said second component of motion, and means stopping said motor drive shaft in a position determined by said control condition to bring said rotatable member to rest in a positioncorresponding to the position of said indicator.
3. An arrangement according to claim 2 wherein said motion-combining coupling means is of a type effecting a reduction of 1:1; between the rotation of said motor drive shaft and said first component of rotary motion of said rotary member, K being an integer; wherein said control means for cyclically producing a control condition comprises a contact, a control cam, gearing for transmitting from said motor drive shaft to said cam a rotation equal to said first component of rotary motion, and means for actuating said contact once per rotation of said cam; and wherein said stopping means comprises aligning means for aligning said motor drive shaft in a fixed position, and means for stoppin said motor drive shaft under Joint control of said contact and said aligning means.
4. An arrangement for automatically and manually controlling a rotatable member comprising a manual drive shaft, a motor drive shaft, a motion-combining coupling means between said two drive shafts and said rotatable member for transmitting to said member a combined rotary motion made up of a first component proportional to the rotation of said manual drive shaft plus a second component proportional to the rotation of said motor drive shaft, an indicator, means for driving said indicator from said manual drive shaft at such rate as to indicate said second component of motion of said rotary member, a control cam, means for transmitting from said motor drive shaft to said cam a rotation equal to i/N of said second component of rotary motion of said memher, an electrical contact, means for actuating said contact N times per rotation of said cam. N being an integer, and stopping means for stopping said motor drive shaft under control of said contact to bring said rotatable member to rest in a position corresponding to the position of said indicator.
5. An arrangement according to claim 4 wherein N is l.
NORMAN E. KLEIN.