US861790A

US861790A - Controller.

Info

Publication number: US861790A
Application number: US34543706A
Authority: US
Inventors: Thorsten Von Zweigbergk
Original assignee: Individual
Current assignee: Individual
Priority date: 1906-11-28
Filing date: 1906-11-28
Publication date: 1907-07-30
Anticipated expiration: 1924-07-30

Description

THORSTEN VON ZWEIGBERGK, OF PRESTON, ENGLAND.

CONTROLLER.

Specification of Letters Patent.

Patented July 30, 1907.

Application in November 2a, 1906. Serial No. 345.437.

To all whom it mayconcem:

. Be it known that I, Tnons'rEN VON Zwniennsex, a. citizen of the United States, residing at Preston, in the county of Lancaster, England, have invented a certain new and useful Improvement in Controllers,

of-which the following is a full, clear, and exact description, reference being had to the accompanying drawings. 1

The object of this invention is to provide a controller for a hoisting or elevator motor which shall automatically establish an electric brake on lower ing, thereby insuring the motor from running away. I accomplish this by providing a resistance which the controller establishes in shunt around the armature in lowering positions, whereby the counter-electro motive-force increasingly developed by increasing speed of the armature automatically checks such armature, forming an electric brake and efliciently limiting the armature spee The invention is hereinafter more fully described and its essential characteristics summarized in the claims.

The drawings are diagrams sufiiciently illustrating the invention,-Figure 1 beinga development of the controller, and Fig. 2 showing the circuits at successive lowering positions.

In the diagrams, the successive positions are indicated by numerals, there being five raising positions and six lowering positionsshown.

A single set of contact fingers is illustrated, and it is to be understood that the controller barrel is turned in one direction past said fingers for raising and in the opposite direction for lowering.

The following reference characters are used.

S and S indicate the raising and lowering contact segments respectively and C the contact fingers.

A indicates the'armature; F thefield of the motor; '1 the source of current, and 'G the ground or return iine;R R R and R the successive sections of the main resistance and r, 1 ,1 the sections of the shunt rcsistance.

On the raising positions, the controller gives the usual resistance government,in the first position connecting the motorfin series with "the entire resistance, and then. successively cutting outv resistance until in the final position (No. 5) the resistance isentirely cut out. In lowering, the'armature is re versed. On the first position, the resistance is maintained in series with the field of armature and'an ad ditional resistance r is established in a shunt around the armature. On the second notch, the resistance around the armature is increased, the shunt passing in series through the resistances r and r. 'Inthe third position, the resistance is further increased,

the shunt passing through the three resistances 1",

ture in the first notch on the lowering side, the motor starts, as the field is already excited to its full capacity and the armature starts by the drop in the voltage across the resistance shunt. As soon as the armature speeds up, the counter electro-motive force cuts down the current in the armature, and actually reverses the current when the speed is high enough to overcome the drop tending thereby to reduce the speed of the armature. Then as the controller is moved to the second notch, the armature receives an increased speed, due to the increased drop in the resistance shunt which is again counterbalanced by the increased counter electro-motive force. On the third position, the still higher and again'receives a check by the counter electro-motive force developed. There is a reversed current flowing on each of the 3 first notches, due to the generative action of the motor as soon as the counter electro-motive force has reached a higher value than the drop in the shunt When it is desired to lower at full speed, the controller is turned successively through positions N o. 4, 5 and 6 which cut out the main resistances. If the motor tends to run away due to the increased momentum of the falling load, on the 3 last notches it is only necessary to throw the controller back onto the third lowering notch which establishes the armature shunt wherein the reversed current will cause an-efiective brake.

With my controller, it is possible to efiiciently and safely operate a hoist without the necessity of constantly shutting off the controller and applying a hand brake when the speed exceeds the safe limit. The electric brake is entirely automatic on the first notches in lowering, and insures against any runningaway. I

Having thus described my invention, I claim:

1. A controller for a hoisting motor having raising positions adapted to govern the motor and lowering positions adapted to reverse the motor and establish a. resistance shunt about the armature with the source of current.

2. A controller for a hoisting motor. having means for reversing the motor and automatically establishing an electric brake for such reversed motor whereby the load may be lowered under control. 1

3. A controller for a hoisting motor having raising posi' tlons adapted to successively cut out resistance and successive lowering positions adapted to maintain connection with the source of current and also establisha shunt around the armature and thereafter open such shunt.

4. In a controller, the combination or contact members arranged to automatically establishresistance in increasarmature speeds while maintaining connection ing amount in 'a shunt around the armature while maintaining connection with the source of current for successive troller, and then to open the shunt and finally to govern the field with said shunt open,

T. A controller for a hoisting motor having raising positions adapted to successively cut our. resistance and iower= ing. positions adapted, while the source of current is connected, to reverse the motor and concurrently establish a. resistance shunt around the armature and thereafter open such shunt and cut out the governing resistance.

8. The combination withi-a motor and. resistance in series with its field ot a control-Jeri having contact members arranged to cut out such resistance for raising and arranged to automatically establish other resistance in a shunt around the armature in increasing amount for successive lowering positionsof; the controller, and then to open the shunt and finally cut out the resistances in series withthe field.

9. The combination with a motor and a field resistance, of a second resistance and a controller having positions which successively establish the second resistance in increasing amount around the armature, then open the shunt and cut out the resistance which was in series withv the field.

10. A controller for a hoisting motor comprising contact fingers and contact plates adapted to cooperate therewith. one set of such' plates corresponding to the elevating rotatiou of the motor, and the other to the lowering rotation, a main. resistance, connections established by the elevating side of the controller for successively cutting out such resistance, a second: resistance,' and connections established by the lowering-side of the controlier for successively establishing such second resistance in increasing amount in 5 the'presence of two a shunt around the armature, then opening such shunt and: then successively cutting out the main resistance.

' 11. A controller for a hoisting motor having raising positlons adapted to connect the motorwith the source of current and. successively cut 'out resistance, and having semen lowering positions adapted to maintain the armature and field in connection with the source of current and with the motor reversed; and to concurrently maintain a shunt cir- -cuit about the armature through a resistance, such resistance being gradually increased and then the shunt circuit V opened for successive lowering positions.

12. A controller for a hoisting motor having raising positions adapted to govern the motor and having lowering shunt about the armature while maintaining connection- With the source of current, there being subsequent lowering positions which open such shunt.

14. The combination with the motor and resistance of a controller having raising positions adapted to. cut out resistance, and lowering positions adapted to reverseand short circuit the armature by a resistance shunt, and having a subsequent position adapted to open such shunt.

15. A controller for a hoisting motor having raising positions adapted to govern the motor, and lowering positions adapted to reverse the field of the motor and establish a resistance shunt about the armature thereof.

16. A controller fora hoisting'inotor' hm ing raising positions adapted to govern the motor, and lowering positions. adapted to reverse the field of the motor and concurrently establish a resistance shunt about the armature, successive lowering positions increasing such resistance and subsequently opening such shun-in v 17. The combination of a motor and resistance in series with its field, of a controller having raising positions adapted to successively cut out such resistance, and having lowering positions adapted" to reverse the held of the motor and establisha resistance shunt around the armature while maintaining a connection from the armature to the source of current, successive lowering positions in- I creasing the resistance in such shunt, and subsequently open-ing the shunt and cutting out the resistance in series with the field.

In testimony whereof, I hereunto affix my signature in witnesses.

I THORSTEN VON ZWEIGBERGK.

" Witnesses:

W1 J2, Sums, H. WATSON.