US2753968A - Rotating remote control devices - Google Patents

Description

July 10, 1956 w STROQ 2,753,968

ROTATING REMOTE CONTROL DEVICES Filed March 3, 1952 i i l 4-0 United States Patent (7 ROTATING REMOTE CONTROL DEVICES Willeboord Stroo, Bussum, Netherlands Application March 3, 1952, Serial No. 274,537

Claims priority, application Netherlands December 22, 1951 2 Claims. (Cl. 192-142) The present invention relates to remote control apparatus, and especially to a novel rotating device for the remote turning of a receiver shaft, by means of an auxiliary motor, to a position corresponding to the rotation of a transmitter shaft, in which the transmitter shaft forms a part of a switch with a contact arm sweeping over a ring of contacts, the contacts of which are connected with corresponding contacts of a contact ring with which cooperates an arm which is coupled with the receiver shaft.

Such devices are known. In the previously known devices, a relatively complicated step switch mechanism was used at the receiver end, which was provided with locking means for stopping and locking the receiver shaft in a position corresponding with that of the giver transmitter shaft. Such step switch mechanisms have the drawback that is is diflicult to make them of small dimensions for a large number of positions, and besides they become slower to set when the number of contacts increases.

The invention aims at providing an adjusting mechanism for the receiver shaft which can be made to operate very rapidly, regardless of the number of possible adjusting positions.

According to the invention the contact arm of the receiver shaft is connected to the coil of an annular or discshaped electro-magnet with radially opposite poles, which is arranged in a housing and declutches the coupling from the auxiliary motor and at the same time locks the receiver shaft relative to the housing as soon as the receiver shaft has reached the position corresponding to that of the adjustment of the transmitter shaft. In this manner a rotating device for remote control is obtained, which can be realized in a simple and compact construction and which has a low weight, and with which a very large number of possibilities of adjustment can be realized with Very short adjusting times.

In practice the disc-shaped electro-magnet is appropriately mounted so as to prevent its rotation, but in a limited axially displaceable manner on the receiver shaft in a stationary housing, and it is coupled with the auxiliary motor by a coupling which is actuated by the axial displacements of the magnet. In this way it is provided that as soon as the receiver shaft has reached the position corresponding with that of the adjustment of the transmitter shaft, the auxiliary motor is declutched from the disc-shaped electro-magnet and at the same time the discshaped electro-magnet, and with it the receiver shaft, are locked with respect to the housing.

Appropriately with this construction the coupling of the disc-shaped magnet with the auxiliary motor is under influence of a spring, which tends to move the coupling to the working or driving position. This ensures that the sticking of the disc-shaped electro-magnet to the housing is prevented, so that the adjusting mechanism, after having been electromagnetically locked, immediately responds to a new adjustment of the transmitter shaft.

When under certain circumstances the adjusted positions of the receiver shaft must be realized very exactly, the electro-magnet and the housing can further be provided with one or more detent pins and recesses corresponding to them, which can arrest the receiver shaft precisely in the selected positions.

In general, then, the invention provides a transmitter in the form of a manually adjustable multicontact rotary switch having a Wiper to complete any selected one of a series of circuits. Each contact of the transmitter switch is connected to a corresponding contact of a similar rotary switch at the receiver, the wiper in this case being driven by an auxiliary motor through an electromagnetically operated clutch which is engaged whenever the circuit of its electro-magnet is interrupted. The two wipers of the respective rotary switches are connected to a current source and the electromagnet of the clutch in a series circuit. Thus, whenever the transmitter switch is set to a contact which does not correspond to the position of the receiver switch, the circuit of the electro-magnet is completely interrupted, the clutch is engaged, and the auxiliary motor turns the receiver wiper (through the clutch connection) until correspondence is obtained. When this occurs, the electro-magnet circuit is completed, disengaging the clutch, and the receiver rotary switch will have turned to the new position called for by the transmitter switch. The auxiliary motor may be a constantly rotating motor, or it may equally well be energized automatically only when a rotation of the receiver wiper is called for, as by means of a relay controlling the motor and connected to the circuit of the electro-magnet so as to be energized whenever the magnet is deenergized.

The invention will now be further elucidated with reference to the drawing, in which a preferred example has been shown in cross-section.

In the drawing, It indicates the transmitter shaft which forms a part of a switch 2 which is adjustable to a large number of positions, e. g, 36. For this purpose the transmitter shaft is provided with an adjusting knob 3 at the outer end, e. g. with a numbered position scale on it, by which the transmitter shaft can be adjusted with respect to an index point on the housing 2. The adjustments are arrested by means of a spring locking mechanism 4 having a locking ball, which can fall into recesses in the housing 2. In the housing the transmitter switch has a contact plate 5 on which in the embodiment shown a contact ring 6 and a circle of contacts 7 with 36 contacts are arranged. With the contact ring 6 cooperates an arm 8 with a sweeping contact 9 which is fixed to the inner end of the transmitter shaft by means of a mounting block 19. The mounting block at the same time carries a second switching arm 11 with the sweeping contact 12 sweeping over the circle of contacts 7. The contacts 7 are each connected by leads 13 with corresponding contacts 14 of a circle of contacts at the receiver end, which circle of contacts is mounted on a plate 15. At the inside of the circle of contacts 14 a contact ring 16 is arranged, corresponding to the contact ring 6. Between the two contact rings the source of current 17 is connected. The contact ring 16 cooperates, in similar manner as at the sending side, with a sweeping contact 13, fixed to a switching arm 19, which is fixedly connected to the receiver shaft 23 by means of a mounting block 22, in the same manner as the switching arm 20 with the sweeping contact 21 which cooperates with the circle of contacts 14. The receiver shaft is made hollow and is journalled free rotatably in the frame plate 24 and carries an annular or disc-shaped electronagnet 25 with the energizing coil 26, the ends of which are connected to the sweeping contacts 18 and 21 by leads through the hollow shaft 23, for example. The disc-shaped electromagnet is turned out at one side so that it has radially opposite poles and it is axially displaceable in a limited manner, but it is coupled for rotation with the receiver shaft 23 by means of a coupling pin 27, which passes throu h axial slots 23 in the hollow shaft 23. The discshaped electro-magnet is pressed towards the frame plate 24 by a spring 2'9 arranged in the hollow shaft and Which in turn presses at one end aga nst the coupling pin 27 and at the other end rests'against a detention member 30. At the side which is turned to the frame plate 24, the discshaped electro-magnet is provided with a coupling disc or toothed wheel 31 which is fixedly connected to it and is brought into engagement with an upstanding rim 32 of an internally toothed wheel 33, by the spring 29. The toothed Wheel 33 is journaled for free rotation on the receiver shaft and is coupled by a toothed wheel 34 on the motor shaft 35 with the auxiliary motor 38 fed from any convenient external power source 40. The discshaped electro-rnagnet and the driving coupling associated with it are mounted in a stationary housing 35, in which also the free end of the receiver shaft 23 is journaled in such a manner that it passes through it. The end Wall 37 of the housing 36 lies at such a distance from the disc-shaped electro-magnet that the driving coupling is just declutched when the magnet lies in contact with the wall of the housing.

When the source of current 17 is switched on, while the sweeping contacts 12 and 21 stand on corresponding contacts, the circuit of the electro-magnet 2d, 26 is closed, whereby the magnet is pulled against the wall of the housing 37, and is locked by the friction, while the driving coupling 31, 32 is declutched. The motor and the driving shaft then rotate freely.

When thereafter the transmitter knob 35 is turned, the circuit of the source of current 17 is interrupted, because the positions of the sweeping contacts 12 and 21 no longer correspond, whereby the coil 26 becomes deenergized and the magnet 25 is immediately pushed away from the housing wall 37 by the spring 29, and the magnet is connected with the driving motor 38 by engagement of the tooth coupling 31, 32. The motor will then turn or rotate the disc-shaped magnet by the shaft 35 and the gear transmission 34, 33 and wil therewith turn the receiver shaft 23 until the contact arm 20 with the sweeping contact 21 has reached again a position corresponding with the position of the sweeping contact 12, whereby the circuit of the source of current 17 is closed again and the electromagnet 25, 26 is re-energized and pulls itself against the housing wall 37 and declutches the driving coupling 31, 32.

Though rotational speeds of the receiver shaft of 120 revolutions per minute in most cases sufiice in practice, whereby each adiustment can take place within one-half second, independently of the number of contacts of the contact circles 7 and 14, tests have shown that the device still works perfectly with a driving speed of 1800 revolutions per minute of the receiver shaft.

When for certain purposes a very accurate fixation of the switching positions is desired, one or more small screws 42 with a conical end can be screwed through the housing wall 37, which screws can cooperate with conical recesses located in the disc-shaped electro-magnet at positions corresponding with the switching positions. The interengaging recesses and pin points may be surface hardened.

Instead of the tooth coupling 31, 32 a conical friction coupling or adequate coupling may be used.

The number of contacts 7 and 14 can be increased or decreased as necessary. The required number of connecting wires 13 may be reduced if the contact circles 7 and 14 form parts of resistances, that is to say are made as branches of resistances, which in turn form parts of a Wheatstone bridge connection, the other two resistances the diagonal connection of which are arranged at the receiver end for instance. The number of connecting wires can then be limited to two, independently'of the number of adjusting possibilities.

The coil for the electro-magnet can also be fixedly arranged at the inside of the housing wall 37, and also the coil can be split up in two parts, one of which is fixed to the housing wall and the other to the disc-shaped part of the electro-magnet, in such a manner that the two parts fit telescopically in one another.

What is claimed is:

l. in a remote control apparatus of the type comprising a rotary transmitter having a rotary contact arm and an arcuate set of contacts disposed for engagement by said contact arm, a rotary receiver comprising a similar rotary contact arm and a second set of arcuately arranged contacts, electrical connections between corresponding contacts of said respective sets of contacts, a source of driving power for the rotary contact arm of said receiver, and clutch mechanism between said source of driving power and the rotary contact arm of said receiver; the improvement which comprises a fixed housing for said clutch mechanism having an end wall formed of magnetically permeable material, a shaft carrying the rotary contact arm of said receiver passing through said housing, an annular electro-magnet surrounding said shaft and connected thereto for rotation therewith'but axially slidably along said shaft between position in which it frictionally engages the end wall of said housing or is spaced therefrom, a spring normally urging said electromagnet to its position spaced from said end wall, the end surface of said electro-magnet facing said end wall defining. concentric annular pole faces to complete a magnetic circuit when said electro-magnet is energized to attract the same into engagement with said end wall, a clutch element carried by the opposite end surface of said electro-magnet, a'cooperating clutch element surround ing said shaft for free rotation but fixed in axial position, said cooperating clutch element being connected with said source of driving power, the clutch elements being so disposed in axial relationship that they aredisengaged when said electro-magnet moves into frictional contact with the housing end wall; and means including a source of electric current completing a series magnet-operating circuit through the contact arm of said transmitter, said electro-magnet and the contact aim of said recei er.

2. Apparatus in accordance with claim 1, including cooperating detent formations on said housing and on the facing-surface of said electro-magnet to define the position of said magnet and thereby of said receiver contact arm as the magnet is pulled into proximity to the housing end wall.

References Cited in the file of this patent UNlTED STATES PATENTS

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