US1156415A - Electrical controlling apparatus. - Google Patents

Description

D. L. LINDQUIST.

ELECTRICAL CONTROLLING APPARATUS.

APPLICATION FILED JULY 31. 1912.

1,156,415. Patented 0%121915.

D. L; LINDQUIST. ELECTRICAL CONTROLLING APPARATUS APPLICATION FILED JULY 31.1912.

Patented Oct. 12, 1-915.

3 SHEETS-SHEET 2.

M W A 1 3 5113% Gum/14mg D. L. LINDQUIST. ELECTRICAL CONTROLLING APPARATUS. APPLiCATION FILED JULY 31.1912.

1,1563% Patented, 0012 12, 1915.

i v 3 SHEETSSHEET 3.

UNITED STATES PATENT ossicn.

DAVID L. LINDQUIST. 0F YONKERS. NEW YUziK, ASSIGNOR TO OTIS ELEVATOR COMPANY, OF NEW YORK, N. Y., A CORPORATION OF NEW JERSEY.

ELECTRICAL CONTROLLING APPARATUS.

Specification of Letters Patent.

Patented Oct. 12, ion 5..

Application filed July 31, 1912. Serial No. 7l2,508.

To all whom it may concern Be it known that I, Dav n L. LINUQUIST, a sub ect of thelung of Sweden, residing at Yonkers, in the county of Westchester.

"for use in connection with furnace hoists.

An object'of the invention is to provide controlling means which will operate automatically gradually to slow downthe skip or loaded bucket as it nears the mouth of the furnace and stop the samethercat, and which will also operate to eflect a quick slowing down and stopping of the bucket at the lowerlii-nit oi its travel.

Iii-the practical operation of single skip furnace hoists difiiculty has been experienced in the control of the motor owing to the. wide variation between the conditions of stopping at'the upper and lower limits of travel. It is desirable that the load be carried upward as rapidly as possible, but as it approaches the furnace the speed must be gradually and smoothly reduced. In order to prevent swinging of the loaded bucket the slowingdown must take place slowly and gradually; the slowing down taking place through a rather long range, and the load must be brought nearly to rest before the brake is fiuallyapplicd; ()n the other hand. the bucket as it nears its lower limit of travel may be quickly slowed downand stopped. the slowing down taking place through a short range of travel only in order to economize time. The brake may also beapplicd before the speed of the bucket has been reduced to the same extent as when loaded. Moreover. thc great di't' fcrcnce in weight between the empty and loaded bucket has a material influence on the operation of the slowing down apparatus. I

.The present invimtion relates to controlling mechanism adapted to meet the above conditions and requirements. and to secure a satisfactory slowing down and stopping of the load carrying device duringboth its upward and downward travel.

The invention comprehcnds the use of a single magnet to control the slow down in both directions, together with means to modify theoperation of the magnet or otherwise modify the operation of the slowmg down mechanism in one direction of travel, so as satisfactorily to fulfil'the qulrements of furnace hoist practice. Such magnet may be divided into a number of sections or magnets, to effect a greater refinement of controh'all of said sections or magnets beingbrought into operation during a single slowing down operation.

' In the accompanying drawings which. illustrate an embodiment of my invention, igure lis an elevation view of a single skip furnace hoist to which my invention is applied:' Fig. 2 is a diagrammatic illr tration of the electrical controlling appz Figs. 3 and s are fragmentary vie ing modifications of the contmllin Referring to Fig. l. the blast it supplied with ore and fuel by means of i bucket- 13 conncrted to a carriage or skip D. The skip is adapted to travel in tracks built on the inclined runway l. The tracks at'both the top and bottom of the runway are curved toward a horizontal position. The skip D is operated by a cable G- con nected at one end to the skip and extended over a direction sheave H at the top the runway. From the sheave H the cable tends downward to a direction sheave I in the powerhouse K. and from thence to an electric motor Bl. When the motor runs in one direction. the loaded bucket is carried up and along the tracks and as it nears the upper end of the runway the speed is gradually "reduced and the bucket, finally allowed to seat on the top of the furnace and discharge its contents. The motor is then run in the reverse direction and the emptied bucketquickly lowered and rapidly brought to rest at the bottom of the run. The electric controlling apparatus the motor as shown diagrammatically in Fig. 2. comprising reversing switches 12, it, an accelerating magnet L. sectional starting resistance 10, a series field coil 20, a shunt field coil 80, and an electromagnetically con trolled brake J. all of which may be of usual or well known construction. The controlling apparatus also comprises the automatic controller geared to the niotor as above noted. a manual switch I). an extra field winding 40. sectional resistance 50, in circuit with the cxtra ficld winding. electroinugnets '60 and 70, automatically controlalso be traced from ling and varying said resistance in accord ance with the speed of the motor, resistances a a2, to modify the operation ofthe magnets 60, '70, and a relay magnet N controlling the extrafield circuit. The mains, designated and respectively, are connected to any suitable source of current supply.

The controller C, as diagrammatically illustrated, comprises a series of concentric rings consisting of segmental contacts and insulating segments. The controller makes substantially a half revolution during the operation of the motor in each direction.

To start the motor in the direction to lift the load, the switch E is moved to the left until the contact 11 which is made in one piece and insulated from the arm of switch E engages the stationary contact .12. This completes a circuit for the magnet of reversing switch R, as follows: from the positive main, through conductor 13, magnet coil 14 of reversing switchR, conductor 15, stationary 'contact 16, segment 17 of the automatic con troller, contact 18, wire 19, contacts 12, 11 of the switch E, and conductor 21, to the negative main.

The magnet 14 being'energized operates the reversing switch R, and establishes a circuit for the armature M ofnthe motor. This circuit may be traced from the positive main, through the contacts 22, 23, of the reversing switch R, lower contacts 24, of reversing switch R, conductor 25, contacts 26, 27 of reversing switch R, conductor 28, motor armature M, conductor 29, contacts 31, conductor 32, starting resistance 10, series field coil 20,-to the negative main. The shunt field circuit is also, established by way of the reversing switch contacts 22, 23, and conductor 33. A circuit for the brake J may the positive main, through contacts 22, 23, 34 of the reversing switch R, conductor 35, brake magnet'winding 36, and conductor 21 to the minus main. Owing to the current through the circuits just traced, the brake is lifted and the motor receives a starting current which is limited by the starting resistance. The closure of contacts 23, 34, conductor 35,

the reversing switch also establishes a cir-- cuit for the accelerating magnet L connected across the brushes of the motor. This circuit may be traced from the brush 41, through conductor 28, reversing switch contacts 27,

26, conductor 25 contacts 24, conductor 33, coil of magnet L, a section of the starting'res'istance 10,

Wire '32, contacts) 31, and wire 29 to the armature brush 42.

The extra field 40, the series field 20 and shunt field 30, all being energized, a powerful magnetic field is produced and the starting resistance also being in circuit with the armature, the latter runs.

"at slow: speed until-the switch E has been moved far enough to connect the contacts 11 sfipeed is reduced.

and 51. With the switch E in this position, a circuit is completed through the relay magnet N, as follows: From the positive main, through reversing switch contacts 22, 23, 34, conductor coil of magnet N, conductor 52, controller contacts 53, 54, 55, conductor 56, switch contacts 51 11, and conductor 21 to the negative lnain. The magnet N being energized, lifts its core-and separates the contacts 4-6, 47, thereby opening the eX- tra field circuit, weakening the motor field; and permittii'ig the motor to accelerate to full normal speed. The eccelerating magnet being connected across the motor brushes operates in a well known manner to successively short circuit the sections of starting resistance 10, and series field 20, to bring the motor up to full normal speed. As the load carrying device moves upward, the automatic controller C rotates in a counter-clockwise direction. The motor runs at normal speed until the insulating section 57 of the controller runs under the contact and breaks the circuit through the relay magnet N. The latter then drops itscore and again completes the extra field circuit through the resistance 50 and field winding 40. The motor field being' thus strengthened the eld circuit has been completed, circuits are established in succession for the magnets 60 and which control the resistance 50. The circuits for these magnets are in parallel with the motor and are controlled by the inner ring of the automatic controller C. Said ring comprises an insulating section 58 and a contact segment 5!). The circuit for the magnet 60 may be traced from the motor brush 42 through the winding of magnet (50, conductor (31, contacts (32 and 59, conductor 63, switch contacts 64, (35, conductor (36, to the motor brush 41. The circuit for the magnet 70 is likewise traced from the motor brush 42, through the coil of magnet 70, conductor 67, controller contacts (38, 59, conductor (33, contacts (34, U5, and conductor 66. After .the extra field circuit has been established as above set forth, the circuit for the magnet 60 is completed by the controller contact 59 running under the contact (32, thereby energizing the n'lagnet 60 and causing it to short circuit a number of sections of the resistance 50, depending on the speed of the motor. If the speed is comparatively high, the magnet (30 will be ener-' Shortly afterthe'magnet 60 has operated,

Shortly after the eXtra' the circuit for the magnet 70 is completed through the controller contacts 68 and 59 so that said magnet operates to further reduce the resistance 50 and eli ect a corresponding further reduction in the speed of the motor.

cuit for the reversing switch magnet is now interrupted by the insulating segment 71 running under the contact 16. The reversmg switch It therefore opened, the current supply cut off from the motor. and the b 'ake' 15 J applied to bring the apparatus to rest.

After the load has been discharged into the furnace the switch I) is moved to the right to reverse the motor. In this instance the circuit is completed through therevers;

ing switch. R and the connection between the motor armature and mains is thus reversed. The starting and acceleration of the motor on a downward movement of the load device is substantially the same as explained Q for the upward travel. As the empty bucket or skip nears its'lower limit the circuit for the relay magnet N is again interrupted, this time at the'contact 72. The circuits for the magnets 60 and 70 are. during the downward travel, completed through resistances a, a2

and m A circuit for the magnet extends through the resistance .2, contacts 73, 74. conductor 75. resistance .r, contacts (34, (i5, and conductor (36. The circuit for the magnet 70 extends through the resistance :1", contacts 76, 74, conductor 75. resistance. .12 contacts Get, (35. and conductor (36. Owing to the resistances 12', .c' and the magnets (30 and 70 will be weaker for a given motor speed than during the upward travel. As a result a smaller amount of the-resistance 50 is short- 'circuited and the extra field remains comparatively weak so that the motor speed is not reduced to the same extent as when the resistances are omitted from the controlling magnet circuits. In other words during the slowing down of the empty car the brake J is applied while thc speed is comparatively high. In order to secure the quick slowing down and stopping of the empty bucket. the 'contacts of the automatic controller C are arranged so that the circuit for the relay magnet N is only broken shortly before the contacts 73 and 76 controlling the magnets and are arranged to complete their circuitsvery shortly after the'magnet N operates and in quick succession. The circuit thrmiglr the reversing switch R is also broken almost immediately after the magnets 60 and 70 have operated. It will be un- ,derstood that any one of the resistances ac, a."

and .ir' may be used alone or that any one of said resistances may be omitted and the other two used together, depending on the bucketv reaches its downward limit The specific results desired in any particular case. The resistances may also be varied to secure any desired variation or relincnieut in the operation of the slowing down magnets. It will be apparent that by the use of the resistances a, .72. and a proper adjustment of the automatic .controller contacts a very quick slowing down and stopping of the empty car may be effected. and also the loaded car may be slowed down very gradually and smoothly. The auxiliary switch (S5, operated by the manual switch E. is antomatically reversed when the switch E is operated. so that the circuits for the magnets 50 and 70 are completed through the resistances only during the downward travel ofthe skip.

'hen the reversing switches are opened a dynamic circuit across the motor armature is established through aresistance 77. This circuit may be traced from the brush 41. through conductor '28. resistance 77. conductor 25. contacts 78, conductor 79. contacts 31, and conductor 29, to the brush 4'). This circuit assists in slowing down the motor.

Fig. 3 illustrates a modification in which an extra resistance 80 is placed in the extra field circuit in series with the resistance 50. Conductors 83 and 8- extending from the opposite terminals of the resistance 80 are connected to switch contacts 81 and 82, the contact 81 being carriedby the core of an elcctro-magnet I. In circuit withthe electromagnet I are switch contacts 91 and 9:2, the contact 91 being carried by the switch E, so that when the said switch is moved to the left to -ause an upward t'avel of the load device. the circuit for the magnet will be completed and the contacts 81 and 82 brought together to short circuit the resistsistances 50. lhe circuit for the resistance- 85 is controlled by a relay magnet I The circuit for the magnet P is controlled by a contact ring 86 of the controller In the slowing down operation during the upward travel of the load. the magnet circuit is open at the insulating strip 87 and the circuit through the resistance 85 remains open. During the downward travel. however, the circuit through the resistance 85 is completed and being in parallel with the resistanee 50, the total resistance through the extra field circuit is reduced with a consequent strengthening of the motor field. The result is a comparatively quick slowing down of the motor, so that the empty bucket may be quickly stopped.

It should be noted that with the present invention as embodied in the various arrangements above described, the same magnet or magnets (50 and 70 control the slowing down of the load device inboth directions of travel and at the same time the rate of slowing down, and the time required to bring the load device to a stop, may be independently regulated and-adjusted to meet the practical requirements of furnace hoisting mechanism. It will be understood that various modifications other than those herein disclosed might be made without departing from the spirit and scope of my invention.

\Vhat I claim is:

1. In hoisting apparatus, the combination of an electric motor, an extra field circuit, resistance in said circuit, an electro-responsive device operating at a certain power to vary said resistance during the slowing down of the motor in one direction, andmeans to modify the power-of said device and effect a different rate of slowing down in the reversedirection.

2. The combination of an electric motor, a load carrying device, an extra field circuit for the motor comprising sectional resistance, an electromagnet connected in a circuit across the motor and controlling said resistance, and means for introducing resistance in the magnet circuit when the motor operates in one direction and for completing a circuit to said magnet independent of the resistance whenthe motor operates in the opposite direction. I

3. The combination of an electric motor, a load carrying device, slow down apparatus comprising an extra field circuit in shunt to the motor and sectional resistance in said circuit, an electromagnet connected in a circuit in shunt to the -motor and controlling said resistance, a resistance inthe electromagnet circuit as the load carrying device is moved in one direction, and means to complete a circuit to said magnet independent of said resistance as the load carrying device ismoved in the other direction.

a. In hoisting mechanism the' combination of an electric motor, a load carrying device, reversing switches, slow down apparatus comprising an extra field circuit, .re--

sistance in said circuit, an electromagnet I adapted to be connected in parallel with the motor armature and controlling said resistance, a resistance for the-electromagnet circuit, and an automatic controller compris ing means to establish a circuit through the said electromagnet and its resistance as the load carrying device approaches one limit of travel and to complete the magnet circuit independently of the resistance as the load -arrying device approaches its limit of travel in the reverse direction.

In hoisting mechanism, the combination of' a motor, apparatus operated thereby, slow down mechanism comprising an electro responsive device controlling the slowing down of said apparatus at different periods in its operation, and means to antomatically vary the power of said electroresponsive device and thereby effect differ- 'ent rates of slowing down for difi'erent periods of operation.

v6. In hoisting apparatus, the combination of an electric motor, a load carrying dcvice raised and lowered by the motor, an' electro-responsive device for slowing down the motor at predetermined points for both direction of travel of the load carrying device, and means forsubjecting said electroresponsive device to the full counter-electromotive force of the motor when slowing down in one direction and for subjecting said device to less than the full counterelectro1notive force when slowing down in the other direction.

7. In a system of electric motor control, the combination of an electric motor, speed reduction mechanism operable automatically to effect a predetermined reduction of speed under varying conditions of load on the motor, and means automatically to modify the operation of said speed reduction mechanism.

8. The combination of an electric motor, speed reduction means automatically to produce a retarding action on the motor varying with the motorspeed, and means automatically to modify the action of said retarding means and thereby effect a different rate of speed reduction.

9. The combination of an electric motor, means for automatically reducing the motor speed in proportion to the load on the motor, and means for modifying the operation of said speed reducing means for. effecting a different rate in the speed reduction also in proportion to the load on the motor.

10; In a system of motor control, the combination of an electric motor, controlling mechanism comprising resistances in circuits of the motor, means operable during the normal slowing down of the motor to antomatically vary said resistance in response to variation of the motor speed, and mechanism to. effect a modified operation of said resistance varying means under other conditions of slowing down of the motor.

mot r, and means to modify the operation of the eleotromagnet by mtroducmg res stonce 1n clroult therewlth.

1-2. The oombinatioh of an electric motor,

controlling mechanism therefor comprising a load 11] agnet, reslstanoe controlled thereby,

a manual controller, means to establish a through the load magnet inclegiencler 'Silld reslstance.

lln testinwny whereof, I have signeil my name to this specification in the presence. of two subscrlbmg WltIlGSSGS.

DAVID L. LIN DQUIS EI.

Witneses:

V. H. B1L\DY',' E. L. ANATELL.

Images