US1520974A - Speed-regulator system - Google Patents

Description

Dec. 1 1,520,974

S. A. STAEGE SPEED REGULATOR SYS/TEM Filed Sept. 2, 1921 INVENTOR iTQRNEY WITNESSES:

Patented Dec. 30, 1924.

UNITED STATES PATENT OFFICE.

STEPHEN A. STAEGE, 0F PITTSBURGH, PENNSYLVANIA, ASSIGNOR T0 WESTINGHOUSE ELECTRIC & MANUFACTURING COMPANY, A CORPORATION OF PENNSYLVANIA.

SPEED-REGULATOR SYSTEIU.

Application filed September 2, 1921.

To all whom it may concern:

Be' it'known that I, STEPHEN A. STAEGE, a citizen of the United States, and a resident of Pittsburgh, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in Speed-Regulator Systems, of which the following is a specification.

My invention relates to regulator systems and it has special relation to systems. adapted to maintain a substantially-constant speed ratio between a plurality of moving members. One object of my invention is to provide a speed-regulator system of the above-indicated character which shall be inexpensive in construction and simpleand efiicient in operation.

Another object of my invention is to provide a speed-1'egulator system of the aboveindicated character which shall embody positive-acting means for preventing hunting action on the part of the regulating system.

Another object of my invention is to provide a speed-regulating system of the aboveindicated character which shall have a corrective movement in two directions, comprising one movement in the direction to secure the needed correction, which movement shall be proportional to the variation to be corrected for, and a second movement. opposite tothe first movement and'prop'ortional to the amount of the preceding corrective movement.

In my copending application, Serial N 0. 460,838, filed April 12, 1921, is described a speed-regulator system of the above-indicated character wherein each set of rotatable members is propelled by a variablespeed motor. Each rotatable member operates a frequency changer that is electrically connected to one winding of a second fre- "quency changer. The other winding of the second frequency changer is connected to a frequency changer that is common to all of the rotatable members and is adapted to supply a'constant frequency. The'second frequency changer is, in effect, an electric differential or a differential. relay. The electric differential actuates a movable brush, which co-operates with a rotatable commutator cylinder to control a shunt cir- Serial No. 497,816.

tomove the brush in the opposite direction to make the proper correction in the operation of the variable-speed motor. In other words, there maybe a tendency for the regulator system to hunt.

The present invention has to do specifically with mechanism for automatically returning the brush the necessary amount to insure perfect corrective action.

Reference may vnow be had to the accompanying drawing, wherein Figure 1 is a diagrammatic illustration of circuits and apparatus embodying my invention, as applied to a plurality of rotatable members;

Fig. 2 is a detail view illustrating the frictional connection between the shaft of the differential. machine and the pawl-andratchet mechanism; and

Fig. 8 is a side elevation of the commutator apparatus, partly in section, in the plane indicated by the line III III of Fig. 1.

Since the apparatus for the sets of ro-- tatable members are alike, the present invention will be described with reference to a single set, and like parts will be given the same reference numerals.

A set of rotatable members is diagrammatically indicated by a roll 11 which is adapted to be driven by a variable-speed propelling motor 12, having an armature 13 and a field-magnet winding 14, through suitable gearing 15. Through speed-changing apparatus 10, the roll 11 operates the rotor 16 of a frequency changer 17 having a stator winding 18 which is energized from any suitable source.

The rotor or secondary winding 16 is electrically connected to the rotor or secondary winding 19 of a second frequency changer 21. the primary winding 22 of which is electrically connected to the secondary winding 23 of a frequency changer 24, which is common to all of the roll units. Frequency changer 24 has a primary winding 25 which is energized from any suitable source, preferably the same as that to which 'However, any'variations in frequency will be indicated by a rotation of the shaft.

,Hence, this freguency changer becomes, in

operation, a d erential mechanism.

Mounted upon the shaft 27 are two ratchet wheels 28 and 29, rigidly connected, together but frictionall 'mounted upon the shaft 27 in any wellown manner, one mountin being illustrated in Fig. 2. The frictiona mounting comprises a disk 31 that is ressed into enga ment with the ratchet 28 means of a spring 32, which has co-opcrating therewith, at its opposite end, a washer 33 and lock nuts 34. v

The ratchet wheel 29 carries a connecting rod 35 having, at its free end, a pair of brushes 36, shown in detail in Fig. 3. Cooperating with the brushes 36 is a commutater cylinder 37 which is mounted upon the shaft 38 of a driving motor 39. Also mounted upon the shaft 38 is a slip-ring 41 which.

has a brush 42 co-operating therewith and is in electrical engagement with the metallic portion of the commutator c linder 37 Included in the circuit 0 the field-magnet winding 14 of the propelling motor 12 1s a resistor 43. A shunt circuit for the resistor is completed through thebrush 42, connected to one side of the resistor, and the brushes 36, connected to the other side thereof.

In the discussion which will follow, it will be assumed that, with the brushes 36 in the central position indicated in Fig. 1, the resistor 43 will be included in the circuit of the field-magnet winding 14 fifty per cent of the time and excluded from that circuit fifty per cent of the time to maintain the pro r speed upon the motor 12, thereby ren ering the differential 21 inactive.

Should there be a chan e in load upon the roll 11, a corresponding" 0 ange in frequency will occur in the differential 21, thus actuating the ratchets to move the brushes 36 a distance roportional to the -load variation and there y vary the strength of the fieldmagnet winding 14 to compensate for the load variation. It will be apparent that, if the load variation is small, re uiring onl a small corrective movement 0 the brushes 36, there will be no tendency for the brushes to over-run the proper correcting position. Should the load variationbe large, requiring a correspondingly lar e movement of the brushes 36, there will e an increasing tendency for the brushes to over-run the roper corrective osition. To prevent such untin action, a ever arm 44 is provided, which is pivoted at 45 and is connected to the ratchet wheel 29 through the dash-pot mechanism 49 so as to receive movements pro rtional to the movements of said ratc et wheel.

The lever arm 44 has mounted thereon, at its fulcrum point, a contact-makin arm 46 which engages either contact mem r 47 or contact member 48, as will be hereinafter described. The lever arm 44 has push rods 51 and 52 mounted at the respective ends thereof which respectively enga e, at their upper ends, with an extension 0% the pawls 53 and 54. Pawl 53 co-operates with ratchet wheel 29 and pawl 54 co-operates with ratchet wheel 28.

It will be noted that the ratchet mechanisms operate in opposite directions and that the pawls engage different ratchet ,teeth in accordance with the positions of .the push rods 51 and 52. Each of the pawls has a bell crank arm 55 secured thereto, the arms each being pivoted as indicated at 56. Mounted upon each arm 55 is an armature 57, co-operating with which are electro-magconnected to the contact members 47 and 48 and are adapted to be selectively energized, as will be hereinafter pointed out.

The pawls 53 and 54 are adapted to describe an arcuate movement, in accordance with the rotation of the shaft 27, through theconnecting, links 61 and 62 which are loosely mounted upon the shaft 27.

In the operation of the mechanism just described, assuming a movement of the brushes 36 toward the left in Fig. 1, and that such movement is excessive, a movement is imparted through the dash-pot 49 to exert an upward pull upon the arm 44 to thus cause the contact-making arm 46 to bridge contact member 48. gizin coil of ma net 59 will then be complete which wil attract the armature 57 to move the associated bell-crank arm 55. In timed relation with this movement, the push rod 52 is lowered to lower the pawl 54. The pawl 54 will enga e different teeth on the ratchet wheel de en ent upon the degreeof'movement of t e arm 44 and push rod 52. Thus, when the electro-magnet 59 is energized to move the pawl 54, the ratchet wheel will move a varying distance dependent upon the ratchet tooth en aged, which, in turn, is dependent upon, an proportional to, the amount of corrective movement required.

Accordingly, when the magnet 59 is energized to move the bell-crank arm 55, which is associated with the awl 54, the pawl will engage the ratchet w eel 28 to rotate the diets 58 and 59. The energizing coils of the electromagnets 58 and 59 are respectively The circuit to the enershaft 27 and also the ratchet wheel 29 to thus move the brushes 36 toward the right in Fig. 1. This second movementis adapted to be just sufficient to establish the needed correction of the motor 12.

By reason of the mechanical connections between the shaft 27 and the pawl 54, and between the disk 29 and lever arm 44, the anti-hunting mechanism is returned to its normal inactive position concurrently with the retroactive movement of the brushes 86. This act-ion will also break the circuit of the coil of electromagnet 59, releasing the pawl 54 from engagement with the ratchet wheel 28. I

Without entering into further detail, it will be apparent that, if the first corrective movement is toward the right in Fig. 1, the downward movement of the dash-pot 46 will effect the opposite movement of the arm 44; to engage the contact arm 46 and contact member 47, thereby completing the circuit to electromagnet 58 and efiecting the abovedescribed anti-hunting movements in co-operation with the pawl 53, producing the same results as those previously described in connection with initial movement in the opposite direction.

It should be noted that the degree of antihunting correction is not always the same. That is to say, every corrective movement of the brushes 36 requires a -movement of the anti-hunting mechanism directly proportional to that corrective movement. Vith the present system, the proportionality between these movements is maintained in ac- .cordance with the variation to be corrected for. Relatively small or slow movements of the brushes 36 require no anti-huntlng action and, hence, the dash-pot will permit the anti-hunting mechanism to remain inactive However, relatively large or quick movements of the brushes 36 will require the anti-hunting mechanism to be operated.

' Modifications in the system and arrangement and location of parts may be made within the spirit and scope of my invention, and such modifications are intended to be covered by the appended claims.

I claim as my invention 1. In a speed-regulator system, the combi nation with a rotatable member, a propelling motor therefor, a resistor in circuit therewith, a frequency changer operated by said member, a constant-frequency source and an electric differential energized in accordance with the two frequencies, of a commutator cylinder and co-operating movable brush circuit-interrupting apparatus adapted to control a shunt circuit for said resistor, said brush being moved in accordance with the operation of said differential, and means adapted tomove said brush in a. direction opposite to themovement by said differentia with a motor, a resistor in circuit therewith,

and a difierential device associated therewith, of a commutator cylinder and co-opcrating movable brush apparatus actuated by said differential device and adapted to control the value of said resistor, said brush being moved in accordance with the operation of said differential, and means adapted to move said brush in an opposite direction at predetermined times.

4. In a regulator system, the combination with a dynamo-electric machine, a resistor in circuit therewith, a constant power source and differential means located between said rotatable member and said source, of a mechanism actuated by said differential means adapted to control the value of said resistor and having a corrective movement in two directions, the first movement producing over-regulation, and the second movement counteracting the over-regulation in a degree proportional to the corrective movement.

5. In a regulator system, the combination with a dynamo-electric machine, a resistor in circuit therewith, of means adapted to control the value of said resistor comprising a differential means and means actuated thereby and having a. corrective movement in two directions, the first movement being proportional to the variation to be corrected,

and the second movement being proportional to the corrective movement.

6. In a speed-regulator system, the combination with a rotatable member, a propelling motor therefor, a resistor in circuit therewith, electric differential means associated with said rotatable member and a commutator cylinder and movable brush circuit-interrupting apparatus operated by said differential and controlling the value of said resistor, of means operable to compensate for excessive corrective movements of said brush.

7 In a speed-regulator system, the combination with a rotatable member, a propelling motor therefor, a resistor in circuit therewith. electric differential means associated with said rotatable member and a commutator cylinder and movable brush amount of movement circuit-interrupting apparatus 0 rated by said differential and controlling t e value of said resistor, of pawl-aind-ratchet mechanismadapted to compensate for excessive movements of said brush, said mechanism having a movement proportional to the said brush. 8. In a regulator system, the combination with a dynamo-electric machine, a resistor in circuit therewith, and a commutator cylinder and a co-operating movable brush adapted to control the value of said resistor, of means for moving said brush to vary the value of said resistor, and pawl-and-ratchet mechanism adapted to compensate for ex- .cessive movements of said brush, both of and pawl-and-ratchet mechanism adapted to also move said brush an amount proportional to the first movement of said brush,

10. In a speed-regulator system, the combination with a motor, a resistor in circuit therewith, differential means associated with said motor, and a commutator cylinder and co-operating movable brush operated by said differential means and ada ted to control the value -of said resistor, o pawland-ratchet mechanism adapted to compensate for excessive corrective movements of said brush, a pivoted lever flexibly connected to said mechanism and carrying a contact-making'arm and a pluralit of push rods adapted to selectively vary t eoperative position of said pawls, and electromagnetic actuating means for said mechanism energized in accordance with the operation of said contact-making arm.

11. In a regulator system, the combination with a dynamo-electric machine, aresistor in circuit therewith, and'a commutator cylinder and co-operating movable brush adapted to control the value of said resistor, of pawl-and-ratchet mechanism adapted to compensate for the excessive cor- .means, a pivoted lever connecte rective movements of said brush, a pivoted lever connected to'said mechanism and carrying a 'contact-makin arm and a lurality of push rods WhlCh' res operate with said pawl mem rs, and selectively energized electroma etic actuating means for said pawl mem rs.

12. In a regulator system, the combination with a dynamo-electric machine, a resistor in circuit therewith, control means therefor, and means for governing said control means in one direction, of pawl-and- -,ratchet mechanism adapted to compensate for excessive operation of said overnin means, a pivoted lever connected to sai governing means and carrying a contactmaking arm and push rods co-operating with said pawls, and electromagnetic actuating means for said mechanism selectively energized by said contact-making arm.

13. In a regulator system, the combination with a dynamo-electric machine, a resistor in circuit therewith, control means therefor, and means for governing said control means in one direction, of pawl-andratchet mechanism adapted to compensate for excessive operation of said governin to sai governing means and carrying a contactmaking arm and ush rods co-operating with said pawls, said pawls being adapted to receive a movement proportional to the operation of said governing 'means, and

ectromagnetic actuating means for said mechanism selectively energized by said contact-making arm.

14. In a speed-regulator system, the combination with a motor and a resistor in circuit therewith, of a commutator cylinder and co-operating movable brush-controlling.

means for said resistor, means for moving said brush in a direction to correct for variations in the speed of said motor, and pawl-and-ratchet mechanism ada ted to return said brush at redetermin times an amount proportiona to the amount of the corrective movement.

In testimony whereof, I have hereunto 100 subscribed my name this 9th day of August, 1921,

STEPHEN A. STAEGE.

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