US1934493A

US1934493A - Selector control mechanism

Info

Publication number: US1934493A
Application number: US486001A
Authority: US
Inventors: Charles P Geyh
Original assignee: General Electric Co
Current assignee: General Electric Co
Priority date: 1930-10-02
Filing date: 1930-10-02
Publication date: 1933-11-07
Anticipated expiration: 1950-11-07
Also published as: DE633313C

Description

NOV. 7, 1933. I c p G H SELECTOR CONTROL MECHANISM Filed 001;. 2, 1930 lnventog'.

Charles T. e h.

by His Attorney.

Patented Nov. 7, 1933 UNITED STATES PATENT OFFICE SELECTOR CONTROL MECHANISM Charles P. Geyh, Oaklyn, N. J., assignor to GengralkElectric Company, a corporation of New Application October 2, 1930. Serial No. 486,001

6 Claims.

electric motor and means for tor to move a control means operating the mofor the apparatus,

selectively to any one of a plurality of predetermined positions corresponding to any one of a corresponding number of preselected conditions of operation or signal channels to which the apparatus may be responsive. In a copending appplication of Charles R. Garrett, Serial No. 480,464, entitled Remote control system for radio receiving apparatus and the like, a remote control system of the above character is shown and described, and includes a selector control mechanism having a plurality of reversing andcontrol switches arranged to be operated by a series of cams for stopping the motor and the controlled device exactly at any one of a corresponding number of preselected positions.

It is more particularly to system of this character that a remote control the present invention relates, and has for its object to provide an improved, simplified and compact selector control mechanism arranged to combine any number of reversing switches with a control means therefor whereby the cams are eliminated.

The invention will better be understood from the following description when taken in connection with the accompanying drawing and its scope will be pointed out in the appended claims. In the drawing, Figs. 1 and 2 are front and side views respectively, both partly in section, of

a selector control mechanism embodying the invention; and Fig. 3 is a wiring diagram of a remote control system embodying the selector control mechanism of Figs. 1 and 2.

Referring to Figs. 1 and 2, 5 is a control shaft for an apparatus, such as a radio apparatus 6,

on which shaft is mounted a commutator or switching means having an insulating body or cylindrical core 7 secured to the shaft 5, and two elongated equal segments 8 and 9 mounted on the core and having a short gap 10 of insulating material between two of the adjacent edges of the segments.

The insulating material is flush with the segments and provides with them a smooth cylinder.

In the present example, the control shaft Sis connected directly with the apparatus 6 which it controls. This apparatus is represented as a variable tuning condenser.

For electrical remote control, the condenser 6 and the control shaft 5 are driven by suitable electrical means such as a reversible electric motor 11, and a reduction gearing including a worm 12 mounted on the motor shaft 13 and meshing with a worm gear 14 mounted on the control shaft 5. The motor is provided with a reversing circuit including two reversing leads 15 and 16 and a reversing circuit return lead 17, together with a pair of leads 18 through which it is energized. With the supply leads 18 energized the motor remains at rest until either one of the

leads

15 or 16 is closed with the return lead 17, the closure of either of the

leads

15 or 16 with the lead 17 causing the motor to operate in one direction or the other.

The motor is preferably of the alternating current, shifting-field type arranged with the

leads

15, 16 and 1'7 connected with suitable shading poles for effecting the reversing and stopping operation of the motor as above described. However, any suitable reversible, electric motor may be employed, which is provided with a suitable reversing circuit having two reversing leads and a return lead therefor as above described. The operation of the motor and its connection in circuit with the apparatus will be described hereinafter. in connection with Fig. 3.

Concentric with and carried by the commutator .cylinder are a plurality of annular rings 19 of insulating material. The rings are freely rotatable upon the commutator cylinder and are in number equal to the number of preselected positions to which it is desired to move automatically the controlled device 6. In the present example seven rings are provided. Each of the rings is provided with an inner recess 20 in which is mounted a flexible spring contact member or brush. 21 secured in the recess and to the. ring, by suitable means such as a pin 22. The contact member is provided with a thin contact end 23 which is sprung into engagement with the commutator cylinder and is of such thickness that it may rest upon the insulating material of the gap 10 without making contact with either of the commutator segments, substantially as indicated carries a contact 21 as above described, but only one appears in the drawing for the purpose of simplifying the latter.

The contact or brush carrying rings 19 may be rotated to provide an adjustment of each contact 21 and may be held in an adjusted position by any suitable means. As a preferred means and as shown in the present example, a worm 24 is provided in connection with each adjusting ring 19 and is arranged to engage teeth 25, moulded or cut in the periphery of the ring. These teeth are preferably straight but may be concaved if desired. Each worm 24 is mounted upon a suitable shaft 26 carried in a bracket 27 secured to a suitable support such as a panel 28. Each of the rings is locked against rotational movement by the worm which engages it and may be moved to adjust the positions of the contact 21 carried by it, by rotation of the shaft 26 through the medium of control knob 29 provided on the end of the shaft of the panel front.

With the above described arrangement the commutator cylinder is arranged to rotate with the control shaft 5 while the contact carrying or contact adjusting rings are held'in fixed positions of adjustment. With the usual tuning device of a radio receiver for example, having substantially 180 degrees of rotation, the length of the commutator segment in a two-segment device is such that the contact 21 of any ring, such as that shown in Fig. 2, may remain in contact with either segment throughout the rotational range of the tuning device.

The peripheral length of the helical teeth in each ring is such that the ring may be moved through substantially the same range of movement as the control or tuning device 6, that is, in the present example substantially 180 so that the contact carried by the ring may be moved to any desired point of adjustment corresponding to any desired position in the range of movement of the controlled device.

Since the range of movement of the commutator and of the contact adjusting ring is less than a full revolution, electrical connections may be made with said contacts 21 and with the commutator segments 8 and 9 through the medium of flexible leads thereby eliminating sliding contacts which introduce contact resistance and are often a source of faulty operation. In Figs. 1 and 2 the flexible lead connections for the commutator segments 8 and 9 are indicated at 30 and 31 respectively, while the flexible lead connections for the various contacts 21 carried by the rotata ble rings 19 are indicated at 32.

It will be noted that the adjusting rings for the contacts or brushes 21 are relatively thin and are placed closely, adjacent to each other. This arrangement serves to reduce the length of the selector control mechanism and to render the mechanism compact. .The length of the commutator cylinder is then only such as to carry the number of rings required for the particular apparatus with which the mechanism is used and to provide a slight additional length at each end of the commutator cylinder for the purpose of making electrical connections thereto. While the rings do not tend ordinarily to move longitudinally of the' commutator cylinder, it is obvious that they may be secured against longitudinal movement by'similar rings at each end of the series of adjustable rings, secured to the commutator cylinder. In order to simplify the drawing such confining rings are not shown. It will be noted. however, that space for such rings is provided on each end of the commutator cylinder.

It will further be noted that because of the compactness of the selector control mechanism afforded by the thin contact adjusting rings, the worms provided for adjusting each ring are staggered alternately above and below on opposite sides of the selective control mechanism or commutator. This arrangement provides two rows of adjusting knobs 29 on the panel and prevents the adjusting worm for each contact adjusting ring from interfering with others on either side thereof. From the drawing it will be seen that the selector control mechanism of the present invention is of relatively small size while providing a plurality of positions of adjustment.

Referring now to Fig. 3 along with Figs. 1 and 2, the selector control mechanism of the present example is shown in connection with a remote control, preselected-channel tuning system. The reversing leads 15 and 16 of the motor 11 are each connected with one of the commutator segments 8 and 9. The adjustable contacts or brushes 21 are connected through suitable selector leads 33 each to one contact of a series of selector switches 34 located in a remote selector unit 35. A second contact 36 for each of said switches is connected through a lead 37, with the reversing circuit return lead 1'7. The various circuit leads indicated at 38 between the selector control mechanism and the remote control unit 35 are pref erably carried in a cable. The motor is energized from alternating current supply leads indicated at 39 which are connected with the motor supply leads 18 through a control switch 40.

The above described circuit arrangement is such that the reversing circuit is completed through the selector control mechanism from either one of the

leads

15 and 16, through the reversing circuit return lead 17, to operate the motor in one direction or the other. As will be seen from the drawing the reversing circuit is completed through one of the commutator segments, one of the contacts 21, one of the selector leads 33 and one of the selector switches 34, the contact and leads being determined by the closure of one of the control switches 34.

With the motor energized from mains 39 by closing switch 40, the motor will operate in the directions indicated in Fig. 3 by the arrows placed upon the commutator, when the reversing circuit is completed through the segment adjacent each arrow and will stop when the reversing circuit is opened by one of the contacts 21 reaching the gap in the commutator. The selected one of the contacts to effect the operation of the motor is determined by closure of a selected one of the switches 34.

It will thus be seen that the controlled device may be moved to a series of preselected positions corresponding to preselected conditions of operation, or preselected signal channels in the case of a radio apparatus, by adjusting a contact carrying or adjusting ring to such position such that its contact 21 will lie in the gap between the commutator segment when the motor has driven the controlleddevice to the desired position. Such positions of adjustment are obtained in each case by adjusting the ring carrying the contact selected for that position by means of one of the control knobs 29 until the contact 21 is moved to a position wherein its contact end 23 lies on the gap 10 in the commutator segment while the controlled device, such as the condenser 6 in the present example, is in a desired position of adjustment.-

It will be appreciated that the difference in dimension between the gap 10 in the commutator and the thickness of the metal of the contact end 23 at the radius of contact determines the angular displacement or error in adjustment which is permitted for the controlled device without causing a corrective movement of the motor. Stated in another way, the accuracy of the remote control depends for the width of the gap 10 in the commutator with respect to the thickness of the contact end 23 of each contact 21. This width should for this reason be greater only by an amount sufficient to fully open the reversing circuit without permitting further movement of the commutator and controlled device in either direction without closing the reversing circuit in one direction or the other. It will thus be seen that this arrangement provides for accurate adjustment of the tuning control device 6 to a desired position under automatic or remote control after the initial adjustment is made.

While seven adjusting rings and contacts are shown in the present example, it will be appreciated that a greater or lesser number may be provided.

The above described switch arrangement has the further advantage that when applied directly to a movable controlled device, as is preferable, it provides in connection therewith a constant mechanical resistance load since the contact is made electrically and not mechanically, that is, the brushes move in contact with a smooth cylinder. It also has the advantage that in production a single commutator cylinder is required having two simple contact segments and the contact or brush carrying mechanism involves duplicate units, each unit being a simple ring and a contact carried by the ring. The teeth on each ring are straight teeth and are not concaved, thereby making for simplicity of construction in manufacture.

What I claim as new and desire to secure by Letters Patent of the United States, is:

1. A remote control system for radio receiving apparatus and the like, including a control shaft, a selector control mechanism connected with said shaft, said mechanism including a rotatable cylindrical commutator device having two segments and having insulating gaps between said segments, a plurality of brushes for the commutator, said brushes being adjustable circumferentially of the commutator and being adapted to lie in said insulating gaps and out of'contact with said segments when moved to an adjusted position and means arranged in a common plane for individually adjusting said brushes and holding the same in positions of adjustment.

2. A remote control system for radio receiving apparatus and the like, including a control shaft,

a rotatable commutator device connected with said shaft and having two conducting segments, said segments having adjacent edges and insulating gaps between said edges, control circuit leads directly connected each with one of said segments,

a plurality of brushes for the commutator, said brushes being adjustable circumferentially of the commutator and being adapted to lie in said insulating gap and out of contact with said segments when moved to an adjusted position, means arranged in a common plane for individually adjusting said brushes and holding the same in positions of adjustment, and flexible leads directly connected to each one of said brushes for connection to a selective control circuit.

3. A multiple-circuit reversing switch including in combination, a commutator cylinder having two contact segments and an insulating gap between said segments, a plurality of annular rings rotatably mounted upon said commutator cylinder, a brush carried by each of said rings and arranged to contact with said commutator cylinder, each of said brushes having a contact end adapted to lie in the gap in said commutator cylinder and out of contact with both of said segments when moved to an adjusted position, and means for adjusting each of said rings to adjust the positions of said brushes.

4. A multiple-circuit reversing switch including in combination, a commutator cylinder having two contact segments and an insulating gap between said segments, a plurality of annular rings rotatably mounted upon said commutator cylinder, a brush carried by each of said rings and arranged to contact with said commutator cylinder, each of said brushes having a contact end adapted to lie in the gap in said commutator cylinder and out of contact with both of said segments when moved to an adjusted position, and means for adjusting each of said rings to adjust the positions of said brushes, said means including a series of teeth provided on a portion 5 of the periphery of each of said rings, a worm arranged to engage each of said rings through the medium of. said teeth, and means for rotating each of said worms to adjust said rings.

5. A selector control mechanism for an electrical remote control system for radio receiving apparatus and the like, including a control shaft, a commutator cylinder mounted on said shaft, said cylinder having two conducting segments separated at adjacent edges by an insulating gap, a plurality of annular ring members rotatably mounted on said commutator cylinder, a brush carried by each of said rings and arranged to engage the commutator cylinder, each of said brushes having a contact end adapted to lie out of contact with either segment of the commutator cylinder when adjusted to a position in contact with said cylinder midway of the gap, and means for individually moving each of said ring members to adjust said brushes.

6. A selector control mechanism for an electrlcal remote control system for radio receiving apparatus and the like, including a control shaft,

a commutator cylinder mounted on said shaft, said cylinder having two conducting segments separated at adjacent edges by an insulating gap,

a plurality of annular ring members rotatably mounted on said commutator cylinder, a brush carried by each of said rings and arranged to engage the commutator cylinder, each of said 3 brushes having a contact endadapted to lie out of contact with either segment of the commutator cylinder when adjusted to a position in contact with the commutator cylinder midway of the gap, and means for individually moving each of said ring members to adjust said brushes, said means being adapted to hold said ring members in adjusted positions, and including gear teeth on the peripheries of said members, worms engaging said teeth, shafts on which said worms are mounted and control knobs for rotating said shafts.

CHAS. P. GEYH.