US809847A - Controller for turbines. - Google Patents

Description

No. 809,847. PATENTED JAN. 9, 1906.

F. SAMUBLSON. CONTROLLER FOR TURBINES.

APPLIOATION FILED JULY 3, 1905.

2 SHEETS-SHEET 1.

Witnesses. In ven tor.

WW W fittg.

PATENTED JAN; 9, 1906.

F. SAMUBLSON. CONTROLLER FOR TURBINES.

AIPLIOATION FILED JULY 3, 1905.

2 SHEBTSSHEET 2.

Inventor Frederick Samuelson.

Witnesses. 4/

UNITED STATES PATENT OFFICE.

FREDERICK SAMUELSON, OF RUGBY, ENGLAND, ASSIGNOR TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

Specification of Letters Patent.

Patented Jan. 9, 1906.

Application filed July 3, 1905. Serial No. 268,026.

To all whom it may concern.-

Be it known that I, FREDERICK SAMUEL- SON, a subject of the King of Sweden, residing at Rugby, England, have invented cer tain new and useful Improvements in Controllers for Turbines, of which the following is a specification.

This invention relates to electric-circuit controllers of a type used more particularly in connection with steam-turbines for controlling the circuits of electromagnetically-operated valves.

Controllers of this kind have been constructed with a cam-cylinder operated by the governor of the turbine, this cylinder actuating a number of switch-contact members which are caused to engage and disengage a metallic contact-cylinder in a predetermined order in accordance with the arrangement of cams employed on the first-mentioned cylinder.

In order to continually change the contactsurface presented by the metallic cylinder to the switch-contact members, it has been customary to connect the cam-cylinder to the metallic cylinder by means of a driving-band but this arrangement is disadvantageous on account of the fact that the number of revolutions of the metallic cylinder is always in proportion to the number of revolutions of the cam-actuating cylinder, with the result that the contact members are liable to engage in the same position on the cylinder a comparatively large number of times, thereby increasing the liability of blackening of the cylinder and impairing the eliiciency of the contact between the switch member and the cylinder.

The object of one part of this invention is to overcome this difficulty; and to this end it consists in utilizing the movement of one of the cylinders to actuate the other by means of an intermittent gear so as to reduce to a minimum the probability of the contact members engaging with the cylinder in the same position, and thereby improving the elliciency of the apparatus.

The invention further consists in providing the controller with means for insuring a quicker opening of the switch-contacts than has been obtainable with the constructions of controller hitherto employed.

In the accompanying drawings, illustrating a controller constructed in accordance with the invention, Figure 1 is a plan of the controller with the top of the casing removed. Fig. 2 is a section of the controller on the line A A of Fig. 1, and Fig. 8 is an end elevation of the controller.

The controller is constructed, as usual, with two parallel rotatable cylinders 1 and 2, the cylinder 1 being constructed of insulating material and provided with a number of actuating-cams 3, suitably disposed on its periphery. These cams are adapted to engage with the extremities of a number of switchlevers 4 arranged in a row on a common pivot-axis 5 and adapted to make and break contact with the surface of the cylinder 2 of the controller. This cylinder has a metallic contact-surface and forms a circuit-terminal common to all the switches. The movable switch members 4 are moved in one direction by means of light springs 6, as shown in Fig. 2, adapted to hold them normally in the closed position.

The cam-cylinder 1 is oscillated or moved to and fro about its axis from the governor mechanism of the turbine by means of a band 7, wound round apulley 8 and connected to an actuating-bar 9, attached to the governor operated mechanism. A spring or equivalent means may be employed for returning it to its initial position. The pulley is loosely mounted on the axis of the cylinder 1 and drives the latter through a pin S,which proj ects into an enlarged aperture inthe pulley, this aperture serving to allow of a limited ro tational movement of the cylinder relatively to the pulley.

In order to increase the speed of break be tween the switch members and the contactcylinder, the cam-cylinder is fitted with a cam disk or wheel 10, which has a number of teeth adapted to engage with a roller 11, carried at the end of a pivoted lever 12, which is controlled by a spring 13. The spring 18 is attached at one end to a fixed support 14 and its other end to a collar 15, which can be screwed along the stem 16 for the purpose of adjusting the controlling force of the spring. The pivot extremity of the lever 12 is formed by a pin 17, which has a bearing in the end plate 18 of the controller-casing.

The cam projections 3 on the cylinder 1 are of varying length, as shown in Fig. 2, so that the switch-levers 4 are forced out of contact with the cylinder 2 by said projections in a predetermined order, the springs 6 causing the levers to move into contact with the cylinder as the ends of the strips pass out of engagement with the extremities of the levers.

The teeth in the cam disk or wheel 10 are arranged so that before a cam projection passes under the extremity of a switch-lever the roller rides over a tooth and is forced into the hollow between this tooth and the next by the spring 13 as the cam projection passes under the switch-lever extremity, thus causing a quick rotational movement of the cylinder 1, and consequently a quick opening movement of the switch-lever away from the metallic cylinder 2. This movement is suiliciently rapid to prevent any possibility of arcing taking place between the contact-surfaces of the levers and the metallic cylinder 2.

The intermittent gear for actuating the metallic contact-cylinder 2 consists simply of a pawl and ratchet wheel. The ratchet-wheel 19 is fixed to the axis of the cylinder2, which axis has a bearing at one end in the pin 17 and at the other end in the end plate 20 of the controller-casing. The pin 17 is fitted with a pawl-arm 21, which carries at its extremity a pivoted pawl 22, Fig. 2, engaging withthe ratchetwheel 19.

As the controller-cylinder 1 is actuated the rocking motion of the pivoted. lever 12 produced by the roller 11 working in and out of the teeth of the cam-disk 10 is transmitted to the pawl-carrying arm 21, thereby causing the pawl to feed the contact-cylinder 2 continually in the same direction whatever be the direction of movement of the cylinder 1, thus reducing the liability of the switch members to engage in the same position of the surface of the cylinder on the repetition of any given circuit change required for the control of the turbine.

What I claim as new, and desire to secure by Letters Patent of the United States, is

1. In an electric-circuit controller, the combination of a cam-cylinder, switch members adapted to be actuated by the cam-cylinder in predetermined order, and means for causing the switch members to open the circuit with a quick movement, substantially as described.

2. In an electric-circuit controller, the combination of a rotatable cam-cylinder, one or more switch-levers actuated thereby, a rotatable contact member, and intermittentlyoperated mechanism driven by the cam-cylinder for causing the contact member to be rotated in a step-by-step manner.

3. In an electric-circuit controller, the combination of a rotatable contactcylinder, switch members adapted to make contact therewith, a cam-cylinder for moving the switch members into and out of engagement with the contact-cylinder, a device for imparting a step-by-step movement to the camcylinder, and means operated by said device for turning the contact-cylinder step by step.

4. An electric-circuit controller comprising a rotatable cam-cylinder, switch members actuated thereby, a rotatable contact-cylinder adapted to be engaged by the switch members, a ca1n-disk attached to the cam-cylinder, a spring-controlled lever actuated by the camdisk, a ratchet-wheel arranged to rotate the contact-cylinder, and a pawl engaging with the ratchet-wheel and actuated by the lever.

5. In a circuit-controller, the combination of a contact element, a plurality of switch members arranged to make contact therewith, a device having cam projections thereon for actuating the switch members, a second cam moving with the device and having projections thereon which alternate with those on the device, and a spring-pressed means acting on and insuring a step-by-step movement of the second cam and a quick break of the circuit by the switch. members.

6. In a circuit-controller, the combination of a cam which has a toandf1'o motion, a contact member, switch members actuated by the cam and adapted to make and break circuit on the contact member, and means for driving the contact member from the cam which transforms the step-by-step motion of the cam into rotary motion of the switch member.

7. In a circuit-controller, the combination of a moving element, a means for oscillating it, a second moving element, means driven by the first element for rotating the second, and switch members actuated by one element and contacting with the second.

In witness whereof I have hereunto set my hand this 20th day of June, 1905.

FREDERICK SAMUELSON.

WVitnesses:

ERNEST HARPER, ETHEL H. WEBB.

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