US1157777A - Control system. - Google Patents

Description

A. J. HALL.

CONTROL SYSTEM.

APPLICAT10N FILED JAN.30.1914.

1,157,777. Patented Oct. 26, 1915.

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ARTHUR HALL, OF WILKINSBUBJG, FENNSYLVANIA, ASSIGNOR '1'0' WESTINGHOUSE ELECTRIC AND MANUFACTURING COMPANY, A CORPORATION OF PENNSYLVANIA.

CONTEQL SYSTEM.

Application filed January 30, 1914.

To all whom it may concern.

Be it known that I, ARTHUR J. HALL, a subject of the King of Great Britain, and a resident of l/Vilkinsburg, in the county of Allegheny and State of'Pennsylvania, have invented a new and useful Improvement in Control Systems, of which the following is a specification.

My invention relates to control systems, and it has special reference to electro-pneumatic means for actuating certain of the control apparatus employed therein. 7

The object of my invention is to provide a device of the above-indicated character which shall be simple and inexpensive in construction and particularly reliable and positive in operation.

In the prior art, devices of the general ernedby connections on the member to be.

actuated and that are normally open to admit fluid pressure to both sides of the piston. By energizing and, consequentIy, closing the valve to release the pressure from either end of the cylinder, immediate and rapid movement toward that end occurs, the movement being continued to the end of the piston stroke or to an intermediate point, dependent upon the time of readmission of the fluid pressure to the cylinder end in reference, by

reason ofthe deenergization and consequent return to the normal open position of the- .shown my invention inconnection with an old and well-known control system and applied to a particular control apparatus mem- Specification of Letters Eatent.

Fatenteol Oct. as, T915.

Serial No. 815,364.

R and another by a switch R a plurality of control switches of a familiar type LS, M, P, S, and G, for effecting the desired circuit changes; a master controller MC and a master reverser MR for energizing the control switches through a suitable control resistor CRand adapted to assume a plurality of motor-accelerating positions a to g inclusive; a main-circuit and control circuit apparatus marked Field change-over and reverser and having the combined functions implied by the name; an electrically controlled, pneumatically-operated actuator 1 for the apparatus just referred to; and a suitable source FP of fluid pressurefor the actuator. I

The general construction of the combined field change-over and reverser is prefer.- ably similar to that of the familiar controller drums, although the reverser is here shown developed into a single plane, for convenient illustration. The apparatus adapted to assume two operative positions in either direction from an imaginary off position the first position in one direction corresponding to the forward running position and the first position in the opposite direction corresponding to the reverse running position, the second position in either case serving to change from full field to normal field connections of the motors, for a purpose well-known in the art.

The actuator 1 comprises a double-acting duplex piston 2; a suitable cylinder or casing 3 therefor; a pair of magnet valves 4 and 5 of substantially familiar or any other suitable construction, which are normally open and which are respectively adapted, when energized, to close and release the normally resent fluid pressure from the correspond? ing end of the cylinder 3; and an oscillating link 6 operatively associated with the piston in the drawing.

Assuming the actuator to be in the for- A ward running position as shown in the drawing, the valves 4 and 5 being deenergized and opento admit fluid under pressure to both ends of the cylinder 3 from the source FP,.the operation of the actuator may be described as follows: Upon the energization of the magnet coil of the valve 4 or 5, as hereinafter described, the corresponding valve closes, thus cutting off communication .with the source FF and releasing the pressure from the corresponding end of the cylinder, whereby an immediate and rapid movement toward that end ensues. To stop such movement, it ismerely necessary to deenergi ze the valve magnet coil in circuit,

whereupon the valve opens and the fluid pressure on opposite sides of the piston is again equalized, the piston, consequently,

'quickly coming to rest in the desired position. I

-As hereinbeforestated, my invention is not limited to any one system of electric motor control and, consequently, only so much of the system here shown will be described as is necessary for a clear understanding of the connection of the actuator 1 with the system. Moreover, the field change-over and reverser whichis shown as I operatively' associatedwith the actuator 1, this being the preferred application thereof,

will not be described in detail .here, inas- Y Y much as theconstruction and operation ofv the reverser are-fully set'forth in a co-pendingjoint application of Norman W. Storer and myself, Serial No. 825,491, filed March 18,1914, and assigned to the Westinghouse Electric and Mfg. Co; It will, of course, be understood that theactuator may be employed in other ways, if desired.

Assuming that the apparatus embodied in,

the control system occupies the positions shown in the drawing, the operation ofthe system, so far as itappertains to my invention. is as follows: If the master reverser MR is moved to the reverse position and the master controller to its position a, a control circuit is established from the trolley, through a conductor 8, control fingers 9 and 10, which are bridged by a contact segment 11, a conductor 12, control resistor CR and conductors-13 and 14 to ground. Another I circuit is established through a conductor 15,

control fingers 16 and 17, which are bridged by a contact member 18 of the master reverser MR, a conductor 19, control fingers 20 and 21, which are bridged by a contact member 22 of the field change-over and reverser, conductor 23 and the coil of the reversing valve 5, to ground, thus energizing the reversing coil of the reverser, which is thereupon actuated to its reverse running position, designated as-RFF, bythe actustraight series relation, as indicated in Fig.

2. This method of operation is familiar, and no further description, therefore, is believed to be necessary here.

In the position d, an energized contact segment 24 .of the master controller engages a control finger 25, whence circuit is completed through a conductor 26, control fingers 27 and 28, which respectively engage contact members 29 and 30 and conductor 31 to the coil of the valve 4. The field changeover and reverser is thus moved to the second or field-changing position, designated as FNF.

When the reverser is moved to its second pos1t1on, by reason of the peculiar shape of the main-circuit contact members 32 and 33, contact is broken with control fingers 34 and 35, and circuit is made with control fingers 36 and 37, respectively. Fingers 34 and 35 arerespectively connected to one end ofthe field windings F and F and the fingers36 and 37 to intermediate points of the respective windings and, therefore, the full field connections of the motors are severally changed to the normal field con- I nections and a higher speed is obtained.

The new control circuits established in I the normal field position of the reverser, may be traced-as follows: from the energized control finger 38 that engages contact member 39 thereof, control finger 40,'conductor 41, stationary contact members 42, at present not connected, but that are adapted to be bridged by a contact member marked R out, when the switch R opens to its lower position, conductor 43, control fingers 44 and 21 that are bridged by the contact member 22, and conductor 23 to the coil of the reversing valve'5.

' By reason of the above described arrange ment of circuits, when, during the actuation before the transition of the motors to parallel circuit relation is effected by the closing of switch G, the opening of switch S and the closing of Switch P, as indicated in Fig. 2. The switch R is then closed and the reverser is again actuated in positions f and g, respectively, in a manner similar to that hereinbefore described.

The above-specified control circuits, which form no part of my present invention except in so far as they eflect their intended functions in conjunction therewith, are more fully set forth in the co-pending application hereinbefore identified.

It will be understood that an operation of .the reverser similar to that just recited will occur when the apparatus occupies its reverse running position, designated as RFF, upon the movement of the master controller MC to either of its positions d or g.

It Will also be understood that the actuation of the field change-over and reverser from the forward to the reverser position, or vice versa, reverses the connections of the field windings F and F through the medium of certain of the contactmembers located upon the lower end of the combined apparatus and the corresponding control 40 fin description of which is not deemed necesgers, in a, well-known manner, detailed sary here.

I do not wish to be restricted to the particular circuit-connections and arrangements necting said piston and said drum, a Supply of fluid pressure, normallyopen means for adm1tting fluid pressure to both ends of said cylinder, and electro-magnetically con trolled means for releasing the pressure from either end to produce a predetermined stepby-step movement toward that end.

2. The combination with a movable member, of an actuating means comprising a piston operatively connected to said member,

' .-a supply of fluid pressure, a cylinder in which the piston operates, valves" normally open to admit the fluid pressure to both ends of said cylinder, and means dependent upon the action of said movable member for temporarily excluding the pressure from either side to produce a predetermined movement toward that side.

3. The combination with a movable member, of an actuating means comprising a piston operatively connected to said member, a supply of fluid pressure, a cylinder in which the piston operates, electro-magnetically operated valves normally open to admit the fluid pressure to both ends of said cylinder, and electrical means operatively connected to the movable member for governing the closure of either valve to produce movement toward that valve.

4. The combination with a movable member adapted to assume a plurality of opera-,

tive positions in each of a plurality of directions, of an actuating means comprising a pair of pistons operatively connected to said member, cylinders in which the pistons operate, means for normally admitting fluid pressure to both cylinders, and electrical means dependent upon the movable member for temporarily excluding the pressure from, and re-admitting the pressure to, either cylinder to produce a step-by-step movement in the corresponding direction.

5. A controller for electric motors comprising a multi-position switching device having main circuit contact members, a movable operating member attached to said device, a cylinder, a supply of fluid pressure, a piston operating within the cylinder, and ,electromagnetically actuated valves normally open to admit the fluid pressure to both ends of said cylinder, the valve-actuating magnets being governed by connections I on said device.

6. A controller for electric motors comprising a control drum provided with main and auxiliary circuit contact members, a movable operating member for said drum, a cylinder, a supply of fluid pressure, a piston operating Within the cylinder, and electromagnetically actuated valves normally open to admit the fluid. pressure to both ends of said cylinder, the valve-actuatin magnets being governed by certain of sai auxiliary contact members.

7. A controller for electric motors com-- prising a single switching device having circuit connections for reversing the motors and for independently changing the field strength thereof, and an actuating means for said device comprising a movable mem'-' ber attached thereto, a piston operatively connected to-said member, means for normally admitting fluid pressure to both sides of said pistonyand electrical means 'for controlling the exclusion of pressure from either side.

8. A controller for electric motors comprising a single switching device adapted to lbs assume a plurality of positions in a forward and 1n a reverse dlrection, the initial posiv tions corresponding to forward and reverse running, respectively, and the subsequent positions being also adapted to change the amounts of the motor field windings in circuit, and an actuator comprising a movable member attached to said device, a piston operatively connected to said movable member, a cylinder in which the piston operates, valves for normally admitting fluid pressure to both ends of said cylinder, and electrical means dependent upon the actuated member for effecting an alternate closure and opening of either valve to produce a step-by-step movement in the corresponding direction.

9. In a control system, the combination with an electric motor, an accelerating resistor, a plurality of control switches and a master switch, of a switching device having a plurality of main and auxiliary contact members, and an actuator for said device comprising a piston operatively connected thereto, a cylinder in which the piston operates, a source of fluid pressure, a pair of trical means dependent upon the positions of said master switch and said auxiliary contact members for governing the valves.

10. The combination with a rotatable control drum, of an actuating means comprising a movable piston, an operating cylinder therefor, an oscillating link member for connecting said piston and said drum, a supply of fluid pressure, a pair of valves normally open to admit fluid pressure to both ends of said cylinder, a pair of actuating coils for the respective valves, and means for energizing said coils under predetermined conditions to eflect movement of said drum in the one or the other direction in' predetermined steps.

In testimony whereof, I have hereunto subscribed my name this 23rd day of Jan.

ARTHUR J. HALL. Witnesses B. B. HINES.

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