US3551791A

US3551791A - Plural voltage divider aggregate

Info

Publication number: US3551791A
Application number: US758828A
Authority: US
Inventors: Wolfgang Labude; Karl-Heinz Bauer
Original assignee: Preh GmbH
Current assignee: Preh GmbH
Priority date: 1968-06-27
Filing date: 1968-09-10
Publication date: 1970-12-29
Anticipated expiration: 1987-12-29
Also published as: DE1765664A1

Description

Dec. 29, 1970 A DE ETAL v 3,551,791

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- HMNW United States Patent 0 U.S. Cl. 323-80 20 Claims ABSTRACT OF THE DISCLOSURE A rotary adjusting aggregate for producing selectively adjustable operating voltages for the control of tuning elements, such as variable capacitance diodes, in which voltage memories include voltage dividers each provided with a rotary gear and positioned at equal angular distances from each other on a common and rotating supporting plate. The supporting plate is rotated by a hollow shaft and can assume any one of a plurality of fixed angular positions. Each voltage divider is actuated by a gear. The actuating gear is fixed to an adjusting shaft which is axially displaceable, to thereby engage a voltage divider. The adjusting shaft is carried within the hollow shaft.

The invention relates to a rotor tuning or adjusting aggregate for producing stored or memorized, selectively adjustable operating voltages for control and tuning elements, especially variable capacitance diodes, for use in communciation receivers, particularly broadcasting and television appliances. In the development of such adjustment aggregates it is known to provide spindle potentiometers on a cylinder shell as voltage storage and to bring the needed voltage storage into the catched or locked working position by rotating the cylinder. Furthermore, it is known to provide on a circular disk radially arranged spindle voltage dividers which may be rotated into the catched working position in the same manner as the cylinder aggregate. It has also been proposed to attach rotatable voltage dividers on a stationary plate at equal angular distances and to pick olf each time the required storage or memory voltage by means of a concentrically arranged step switch.

The arrangements known or proposed, respectively, are however, relatively expensive and complicated and do not satisfy completely the requirements for as simple as possible operation.

The invention is directed to forming the components for switching on the required memory voltage and for the adjustment of the same in such a manner that they may be operated as simply as possible, that in a suitable manner they are subordinated to the entire design of the apparatus, and that they fulfill the requirements of shape.

A further object of the invention consists in rendering the construction, especially of the voltage divider system, so simple that it can be manufactured most economically by mass production methods.

It is another object of the invention to design a rotor adjusting aggregate in such a manner that its construction is most stable, compact and reliable in service.

In accordance with the present invention it is proposed to so design a rotor adjusting aggregate for supplying memorized, selectively adjustable operational voltages for control and adjustment components or elements, especially variable capacitance diodes, in which the voltage memories consist of rotary layer-voltage-dividers arranged at equal angular distances on a common supporting plate and each being provided with a gear so that the supporting plate of the voltage memory is rotatable by means of a hollow shaft into the catch positions and so that the gear of the voltage divider being at that time in working position can be coupled by axial displacement to an adjustment shaft common to all voltage dividers, which is guided in the hollow shaft.

On account of the concentric support of the operating shafts for voltage selection and switching on of voltage, the corresponding operating elements are coordinated with each other, whereby the operation is simplified and facilitated. The voltage once memorized cannot inadvertently be changed since the slider of the then switchedon voltage divider is adjustable only after the coupling is engaged.

In a first embodiment of the voltage adjustment device according to the present invention, the adjustment shaft is provided with a pinion and a conical surface, which in the uncoupled position of the shaft rests against a counter conical part of the hollow shaft, so that the adjustment shaft upon its displacement in axial direction is brought into a position parallel to the axis of the hollow shaft whereby an intermediate wheel, pivotable against spring action and meshing with its pinion, is brought into engagement position with the gear of the rotating voltage divider which is at that time in an operating or Working position with respect to certain common contacts.

In a second embodiment of the voltage adjustment device according to the present invention, it is proposed to provide the adjusting shaft, which is axially displaceable and which is concentrically supported in the hollow shaft, with a pinion which is engaged by a rotatably supported intermediate wheel which on its part is brought by axial displacement of the adjusting shaft against spring action into engagement position with the gear of the rotatable voltage divider then being in working position.

In both arrangements fine adjustment of the voltage divider is obtainable by corresponding selection on the gear ratio between the pinion and the gears of the rotatable voltage dividers.

An advantageous feature of the voltage divider system is proposed in accordance with the present invention, in which the resistance elements of the rotatable voltage dividers are applied as layer resistance surfaces and their conducting connections are applied as conductive silver strips directly on a rotary supporting disk consisting of insulating material by known methods such a spraying, printing or the like. The application of all resistance layers and all conducting silver connections may be carried out in one operation, whereby the production costs are materially lowered. The making of the conducting connections may also be done by known methods of producing printed circuits.

A lowering of the production costs of the voltage divider system is achieved in accordance with a further proposal of the invention thereby that the gear wheel of each rotatable voltage divider is die-cast as one piece with a shaft extension on both sides of a bearing bore in the supporting plate in such a manner that it is fixed in axial direction but is by shrinkage rotatable in the bearing bore with a certain breaking moment.

According to a further proposal according to the present invention, the hollow shaft is non-rotatably connected with the supporting disk by a hub of synthetic resin diecast into place. Inasmuch as this operation may be carried out simultaneously with the die-casting of the gear wheels, a further shortening of the manufacturing time of the voltage divider system is achieved.

For applying the slider to the respective rotor voltage divider it is proposed in accordance with the present invention, to secure the same in the shaft projection of the gear wheel by means of a bolt, the slider serving in co- 3 operation with the stationary counter contact as pickoif contact. The collector ring, customarily employed in rotor voltage dividers, and a special step contact are hereby eliminated.

A hand may also be applied on the same bolt, which hand indicates in a corresponding cutout of the housing of the device the slider position of the respective rotor voltage divider then being in the working position.

For switching on the input voltage to the adjusting aggregate, the starting and final connections of the rotor voltage divider are formed in a first embodiment as switching contacts and are arranged so that the contacts of the rotor voltage divider then being in working position is applicable through two stationary counter contacts to the input voltage. In this embodiment at one time one voltage divider only is applied to voltage, resulting in a relatively small current consumption.

According to a further proposal according to the present invention, the starting and the end connections of each other and with one sliding ring each, which pick the input voltage off stationary counter contacts. In this arrangement, with switched on receiver, all voltage dividers are simultaneously applied to voltage so that, upon switching over of the voltage dividers, a voltage drift, which might be produced by the load, is avoided.

In a third arrangement according to the present invention, the rotor voltage divider or single groups thereof are connected in series, under given conditions with the insertion of fixed resistances, and these in-series wirings are connected over slide rings in cooperation with stationary counter contacts to the input voltage. In this in-series (wiring each voltage divider is coordinated with one definite fixed partial range of the total voltage in the confines of which the memory voltage is adjustable.

In receivers having more than one receiving range it is desirable, upon switching-on of a certain voltage memory, to switch on simultaneously the range to which this memory belongs. For solving this problem it is proposed, in accordance with the present invention, to provide a synchronously running switching disk on the hollow shaft concentrically with the suporting disk, the outer margin of said disc consisting of circle segments with such radii that the particular group belonging to the respective circle segment of the rotor voltage divider corresponds with the outer margin to a range switch of the switch position for a definite receiving range, said range switch being secured to the housing of the aggregate.

As a further feature of the invention, for multiplerange receivers in which each voltage memory is assigned to different receiving ranges, rotor bolts and/ or cams are attached to the periphery of the supporting disk at equal angular distances. Such cams cooperate with a range switch provided on the aggregates housing and a predetermined receiving range can be switched on.

The invention and its details will be more closely explained by means of the drawings of different embodiments.

In the drawings:

FIG. 1 shows a section along a plane extending vertically to the axis of rotation of a rotor adjustment aggregate having six voltage memories, and is a view along section D-D of FIG. 2;

FIG. 2 represents an axial section of this device with a pivotable intermediate wheel;

FIG. 3 shows an axial section of another embodiment of an aggregate with an axially displaceable intermediate wheel;

FIG. 4 shows part of the front elevation of a receiver with the adjustment aggregate of either FIG. 2 or 3;

FIG. 5 is a symbolic representation of the voltage divider of the embodiments of FIGS. 2 and 3;

FIG. 6 is a symbolic representation of an aggregate having eight voltage dividers wired parallel to each other; and

FIG. 7 is a symbolic representation of an aggregate having two groups of voltage dividers arranged in series.

The adjustment devices according to FIGS. 1, 2 and 3 comprise a bushing 1, a housing 2 of the aggregate and a hollow shaft 3 of a rotor, shaft 3 being supported in bushing 1. This rotor consists of a disk 4 of insulating material, including a hub 5 of synthetic material, die-cast onto the disc and shaft 3 is nonrotatably connected with hollow shaft 3. Disk 4 is provided with six bores arranged at angular distances of sixty degrees from one another. Six synthetic resin gear wheels 6 are die-cast onto a shaft extension 7 on both sides of the supporting disk 4 so that they are axially fixed but, on account of the shrinkage in the bearing bore, are rotatable upon overcoming a certain braking moment. Annular layer resistance strips 8 are directly applied to the supporting disk 4 concentrically to the gear wheels 6 and are connected by conducting

silver webs

9, 10, 11 to contact pins 12, 13. The resistor 14 is applied between the conductor silver strips 9, 10 as affixed basic resistance for limiting the variation range of the voltage divider. The contact bolt 15 is nonrotatably inserted in a bore of shaft extension 7 and has attached to it the resilient slide 16.

A contact support 17 having three

resilient contacts

18, 19, 20 is secured to the outer wall of housing 2. Contact

pair

18, 19 cooperates with the contact pins 12, 13 of the rotor voltage divider being at a given time in working position (upper part of FIG. 1) and contact 20 is simultaneously biased against the end of contact bolt 15. Catch roll 21 is secured to the housing wall by spring yoke 22, the roll sequentially entering into notches 23 of the sup porting disk 4 to thereby determine the six angular positions of the latter,

In the example of FIG. 2 the adjusting shaft 24 is arranged in hollow shaft 3 of the rotor, shaft 24 being guided in a ring 25 of the hollow shaft and resting in the uncoupled (.rest) position with its conical part 26 on the counter conical part 27 of hub 5. A pinion 28 is provided on the forward end of the adjustment shaft and is permanently in engagement with an intermediate wheel 30 rotatably supported on spring yoke 29. Upon displacement of adjustment shaft 24 in the direction of arrow A the conical surface 26 slides on conical surface 27 whereby the adjustment shaft is brought into the axial middle position and the intermediate Wheel 30 is pivoted against the spring action of yoke 29 and brought into engagement with the gear wheel 6. In this position of the adjustment shaft, the slider 16 of the rotor voltage divider then being in operating position can be fine-sensitively adjusted by knob 31 (FIG. 4) which is attached to shaft 24.

In the embodiment according to FIG. 3, the adjustment shaft 24, on which pinion 28 is secured, is supported in cover plate 47 of the aggregate and concentrically by ring 25 in hollow shaft 3. Shaft 50 of intermediate wheel 30* is axially displaceable in bearing bushing 48 against the force of spring 49, intermediate wheel 30 being in permanent engagement with pinion 28. By displacement of adjustment shaft 24 in the direction of arrow B, intermediate wheel 30 is brought into engagement with the particular gear wheel 6 of the rotor voltage divider then being in working position, the fork spring 51 snapping simultaneously into groove 52 of adjustment shaft 24 by which the rotor voltage divider may now be adjusted by turning knob 31 secured to shaft 24.

Hand 33 is placed by bushing 32 on bolt 15 (FIG. 2) and indicates in a window 34 of the aggregate housing 2 the respective position of the slider. The aggregate is arranged in the appliance so that window 34 lies behind a scale arrangement 35 (FIG. 4) on the front wall of which channels assigned to the individual voltages are indicated whereby the then adjusted channel is shown by the hand.

The device should also be employable for receivers having two ranges, in which each memory or storage may be assigned to both ranges. For this purpose six rotary bolts 36 are inserted with a laterally die-cast on cam 37 into the periphery of supporting disk 4 (FIG. 1), the cam being pivotable by means of a screw driver in overcoming a certain braking moment in such a manner about 90" that the middle axis of the cam extends either in radial or tangential direction relative to the center of the aggregate. Range selection switch 38 is arranged on housing 2 in such a manner that its contact is closed by radially extending cam and that the switchings required in the device are triggered by magnet switches or switching diodes. Consequently, depending on the position of the cam of the coordinated rotatable bolt 36, each voltage memory or storage may either be assigned to the one or to the other range.

The range adjustment is effected from the front side of the device through a cut-out 39 (FIG. 4) of its front wall and a passage 40 in the aggregate housing, the then adjusted range being simultaneously shown by the vertical or horizontal position of the adjustment slot and is readable on the double scale 35 of the corresponding channel. Note the symbolic representation of the slot positions at the end of each scale.

Regarding the electrical arrangement of the rotor voltage divider, symbolically shown in FIG. 5 for the example of FIGS, 1, 2 and 3, various embodiments are possible which for the same or similar mechanical design of the individual voltage dividers and of the means for adjusting them are adapted to the different requirements and are symbolically shown in FIGS. 6 and 7.

FIG. 6 shows a wiring of the voltage divider in WhlCl'l at each time all starting and final connections of the dividers are connected with one another and with a

slide ring

41, 42 each, to which the input voltage through the

slide contacts

43, 44 is fed. This arrangement is distinguished from the first embodiment merely in that when the device is switched on, all voltage memories s1multaneously carry voltage.

The electric arrangement of the voltage dlviders of a further embodiment is shown in FIG. 7, in which the individual voltage dividers are connected in two groups I, II of three or five memories, respectively, and are connected in series with the interposition of constant resistances 45. The two groups are on their part connected in parallel and with the

slide contacts

41, 42, which take the input voltage off

slide contacts

43, 44. In this arrangement, a small voltage only for a predetermined channel is assigned to each memory, within which the memorized voltage is adjustable for equalizing tolerances and for subsequent tuning of the receiver. I

Herein the two memory groups I, II are assigned to two different receiving ranges. Upon switching on of one memory of group II the contact of range switch 38 is closed by the margin of switch disk 46 in the same manner as by the radially adjusted cam 37 of the first example of the range appertaining to it by subsequent, not illustrated, switching means.

While there have been described what at present are believed to be the preferred embodiments of this invention, it will be obvious to those skilled in the art that various changes and modifications may be made therein without departing from the inventon, and it is aimed, therefore, to cover in the appended claims all such changes and modifications as fall within the true spirit and scope of the invention.

What is claimed is:

1. In a rotor adjusting aggregate adapted to selectively adjust voltage for control and tuning components, a plurality of voltage memories each comprising a rotor-layervoltage-divider and a gear wheel, a common supporting plate, said voltage-divider being attached to said plate at equal angular distances from each other, a stationary supporting structure, a hollow shaft secured to said plate, means on said structure adapted to support said hollow shaft and said plate rotatably about the axis of said shaft, means adapted to releasably lock said plate and shaft in a number of different positions relative to said structure, said number of positions being equal to the number of said voltage dividers, an adjusting shaft common to all voltagedividers, means adapted to guide said adjusting shaft slideably in its axial direction within said hollow shaft, a pinion secured to said adjusting shaft outside of said hollow shaft, means adapted to displace said adjusting shaft and its said pinion in axial direction and thereby to effect selectively meshing of said pinion with said gear wheel of one of said voltage-dividers.

2. Adjustment aggregate, as claimed in claim 1, wherein the adjusting shaft is provided near said pinion with a portion presenting an outer conical surface and said hollow shaft with a portion presenting an inner conical surface of larger diameter than and in the same longitudinal region as said outer conical surface, spring means, adapted to keep said surfaces in contact with one another, said means which are adapted to guide said adjusting shaft slideably within said hollow shaft, being arranged at a distance in an axial direction of said shaft from said conical surfaces and being additionally adapted to permit pivotal movement of said adjusting shaft relative to said hollow shaft, said adjusting shaft being pivoted with its said pinion into engagement with one of said gear wheels upon its displacement in axial direction relative to said hollow shaft.

3. Adjusting aggregate, as claimed in claim 2, wherein an intermediate gear wheel is kept in permanent engagement by said spring means with said pinion and wherein displacement of said adjusting shaft and pinion is adapted to bring said intermediate wheel selectively into engagement with one of said voltage-divider gears.

4. In an adjusting aggregrate, as claimed in claim 1, an intermediate gear wheel, means adapted to support said intermediate wheel rotatably and axially displaceable relative to said voltage-divider gear and axially movable and in permanent engagement with said pinion, spring means adapted to urge said intermediate wheel into a position of disengagement with said voltage divider gear so that axial movement of said adjusting shaft and pinion with said intermediate wheel in overcoming the bias of said spring means establishes driving connection between said adjusting shaft and said voltage-divider gear.

5. Aggregate, as claimed in claim 1, wherein said voltage memories are formed as resistance layers and connecting means for said surfaces are formed as conductor silver strips applied directly on said supporting plate, said plate consisting of insulating material.

6. Aggregate, as claimed in claim 1, wherein said gear wheels of said voltage dividers are die-cast in one piece with a shaft extension on both sides of a bearing bore provided in said supporting plate, thereby establishing axial fixation and frictional rotary retention of said wheels in said plate.

7. Aggregrate, as claimed in claim 1, wherein said supporting plate and said hollow shaft are rigidly interconnected by a synthetic resin hub die-cast between them.

8. Aggregrate, as claimed in claim 1, wherein an extension is provided on said voltage-divider gear, a contact slide is rotatably secured in said extension by a bolt, and a pickolf contact element engages said bolt and is supported by said supporting structure.

9. Aggregrate, as claimed in claim 8, wherein an indicator hand is secured to said bolt of each voltage-divider, a wall of said supporting structure is arranged in front of said hand, and said wall defines a window opening permitting observation of said hand.

10. Aggregrate, as claimed in claim 1, wherein input and output taps of the rotor-voltage-divider are adapted in operating position to be connected to counter contacts stationarily held by said supporting structure, said counter contacts being adapted to be connected to a source of input voltage.

11. Aggregrate, as claimed in claim 1, wherein input taps of said voltage dividers are connected with each other and each with a slide ring adapted to pick an input voltage off a source of such voltage.

12. Aggregate, as claimed in claim 1, wherein output taps of said voltage-dividers are connected with each other and each with a slide ring adapted to pick an input voltage off a source of such voltage.

13. Aggregrate, as claimed in claim 1, wherein input taps of individual groups of said voltage-dividers are connected with each other and each with a slide ring adapted to pick an input-voltage off a source of such voltage.

14. Aggregrate, as claimed in claim 1, wherein output taps of individual groups of said voltage-dividers are connected with each other and each with a slide ring adapted to pick an input voltage off a source of such voltage.

15. Aggregrate, as claimed in claim 1, wherein said voltage dividers are wired in series and said in-series wiring is adapted to be switched onto a source of input voltage by means of slide rings coacting with stationary contacts.

16. Aggregrate, as claimed in claim 15, wherein constant resistances are inserted between said in-series wired voltage dividers.

17. Aggregrate, as claimed in claim 1, wherein individual groups of said voltage dividers are Wired in series and said in-series wirings are adapted to be switched onto a source of input voltage by means of slide rings coacting with stationary contacts.

18. Aggregate, as claimed in claim 17, wherein constant resistances are inserted between said groups of said inseries wired voltage dividers.

19. Aggregrate, as claimed in claim 1, adapted to be used in receivers having more than one receiving range, said aggregate having a switching disc concentrically secured to said hollow shaft and adapted to move synchronously with said supporting plate, said switching disc having an outer margin presenting circle segments of such radii as to adapt a group of voltage dividers appertaining to each one of said segements in cooperation with a range switch secured to said supporting structure to be assigned to the switch position of a predetermined receiving range.

20. Aggregrate, as claimed in claim 1, adapted to be used in receivers having several receiving ranges, said aggregate having pivotable bolts secured on the periphery of said supporting plate at angular distances equalling the distances of the voltage dividers, said bolts each carrying a cam, said cams in one of their positions being adapted to coact with a range switch supported by said supporting structure so as to switch on a predetermined receiving range for the voltage-divider being in operating position.

References Cited UNITED STATES PATENTS 12/1936 Kalencik 33876X 8/1963 Shelley et a1. 338131X US. Cl. X.R.