US1118443A - Means for changing the output of centrifugal compressors. - Google Patents

Description

R. H. RICE.

MEANS FOR CHANGING THE OUTPUT 0F OENTRIFUGAL GOMPRESSORS.

AIPLIOATION FILED OUT. 3. 1911.

I 1,1 18,443. Patehted Nov. 24, 1914.

Wibnesses Inventor? I Richard 'H. Rice, 4

UNITED STATES PATENT OFFICE.

RICHARD H. RICE, OF WEST LYNN, MASSACHUSETTS, ASSIGNOR T0 GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

MEANS FOR CHANGING THE OUTPUT OF GENTRIFUGAL COMPRESSORS.

. Application filed. October 3, 1911.

To all whom it may concern:

Be it known that I, RICHARDH. RICE, a citizen of the United States, residing at West'Lynn, county of Essex, State of Massachusetts, have invented certain new and useful Improvements in Means for Changing the Output of Centrifugal Compressors, of which the following is a specification.

Centrifugal air compressors when .employed in the usual and normal manner in blast furnace work, furnish a constant or substantially constant number of cubic feet of free air per minute. There are times, however, when the amount of air required by the consumption devices is only a fraction of the normal amount delivered by the compressor. The problem presented is, therefore, to provide agoverning mechanism for a compressor and its driving motor which is capable of being so adjusted or modified in its action, that the compressor instead of delivering its normal output, may deliver any fraction thereof at a predetermined pressure. The adjusting or modifying means must operate in a simple manner, requlre' little time to adjust and not necessitate shutting down the apparatus or taking it apart in making said adjustment.

For a consideration of what I believe to be novel and my inventiom lattention is di: rected to the accompanying description and claims appended thereto.

In the drawing is shown a centrifugal compressor and a turbine for driving it, the compressor and turbine being shownside by side to simplify the illustration.

1 ipdic'ates a driving motor. This may be a steamturbine of the Curtis or other type. It is provided with a regulator comprising a valve chest 2, containin one or more valves that are actuated by t e cam shaft 3 in the well-known manner. On the shaft is an arm 4; that is actuated by a float located in the intake of the compressor.

5 indicates a part of the casing of a centrifugal compressor and 6 the intake therefor. Located within the intake pipeis afloat 7 Specification of Letters Patent.

Patented Nov. 24:, 1914.

Serial No. 652,564.

that rises and falls as the rate of flow of air through the compressor varies. The float operates in the manner set forth in my Patout 919,953, dated April 27, 1909, and this invention may be regarded as an improvement over that claimed in said patent.

- The structure of the patent is, however, arranged to deliver fluid at but one predetermined constant rate of flow, whereas the structure of the present invention is arranged to deliver air at many different rates of flow, each of which is constant when once established. The float 7 is mounted on a rod 8 thatextends upwardly through the top of the casing and is connected to the tilting scale beam 9. This beam is pivoted at 10 on the bracket 11 and is provided with teeth or notches to hold a weight in position, as will appear later. The beam also has a suitable scale to guide the attendant in making adjustments. In the present instance as an illustration, a quadratic scale is provided and laid oil to indicate zero-flow, also a flow of twenty thousand, thirty thousand and forty thousand cubic feet of free air per minute. Connected to the beam is an arm 12 that is united by the rod 13 with the regulator of the motor, as for example with the arm 4 on the cam shaft of the steam turbine. To the left hand end of the beam is connected a rod 14 and piston 15, the latter being located in the cylinder 16 and cooperating therewith to form a dash-pot. An adjustable by-pass 17 serves to regulate the ell'ective action of the dash-pot.

Mounted on the right hand endof the beam 9, and adjustable thereon, is a weight 18 that counterbalanccs to a certain predetermined extent, the weight of the float 7, dash-pot parts,.etc. The remainder of the weight is supported by the fluid flowing upward through the intake. This weight 18 is usually adjusted once for all when the parts are initially assembled. It correspondsin function to the weights 23 of myPatent 919 953, aforesaid, but it has the *advantage of eing more readily adjustaiglcQLWithinlividual weights supported as in said patent, considerable work may be involved 1n getting the exact balance desired.

The means for adjusting the mechanism to cause ditlerent but constant rates of flow of air at predetermined pressure to be delivered will now be considered.

Mounted on the notched scale beam 9 is an adjustable sliding weight 19 having a suitable handle for moving it. When the weight 19 is in the zero-flow position and the weight 18 is in the proper position, the parts are balanced. Air flowing upward through the intake exerts a force on the lever 9 through the rod 8, tending to move it upward. As the weight 19 is moved along the scale beam from the position shown, to-

- ward the left, the opposition to the upward movement of the float is changed and the rate of flow of air through the compressor is therefor increased. This is due to the fact that the changed position of the weight causes a depression of the left hand end of the beam and with it the float 7 to a new and lower position. This action moves the regulator of the motor in a direction to cause the speed of the motor to increase. Naturally as the speed of the motor increases, the impeller of the compressorvwill rotate at a higher speed and discharge a greater amount of air per unit of time. The amount of air flowing through the intake will, for any given condition, ultimately reach such a value as to balance the effective action of the Weight 19 on the beam and when this occurs the speed of the driving motor will become substantially constant as will also the output of the compressor. This output is greater for each successive position of the weightl toward the left from the initial position. The parts are so proportioned and related, that a movement to the left of the weight 19 steadily increases the rate of flow per unit of time until the maximum is reached when the pointer 21 will enter or coincide with the notch in the scale beams indicating 40,000 cubic feet of free air. To decrease the rate of How, assuming the weight 19 to be set for maximum delivery, said weight is moved to the right which permits the float and cooperating beam to close one or more valves in the turbine and decr ase its-speed.

The we ght of the dashpot rod 14 and piston 15, he float 7 and its red 8, etc.. make the zero position of the weight 19 fall considerably to the right of its pivot 10, as shown. and for ordinary ranges of velocity this allovs the beam 9 to be pivoted about its middle instead of at or near its left-hand end. This makes the apparatus more compact and convenient.

The compressor illustrated is intended for a maximum output of 40,000 cubic feet of free air per minute, but my invention is not limited thereto asit is: capablebf wide ap- I plication.

- The scale beam occupies a substantially horizontal position at all times, and since patent statutes, I have described the principle of my invention, together with the apparatus which I now consider to represent the best embodiment thereof; butl desire to have it understood that the apparatus shown is only illustrative and that the invention can be carried out by other means.

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

. 1., The combination of a rotary compressor, a driving motor and regulating means therefor, a float located in a passage through which the fluid acted on by the compressor passes so as to float on the. flowing fluid and respond to variations in its rate of flow, a

rod'connectedwith said float and extending.

In accordance with the provisions of the,

through the-wall of said passage, a beam pivotally mounted on said wall to which said rod is connected intermediate its ends at one side of the pivot, a weight at one end of said beam for the purpose of initially balancing it under conditions of zero flow, an additional weight adjustable along said beam. to enable the device to be set so as to maintain any desired rate of flow, said beam having on it a scale for indicating the rates of flow corresponding to various positions of said latter weight, a dashpot device comprising a stationary part secured to saidwall and a movable part connected to said beam at the other end, and an operative connection joining said motor regulating means to said beam at a point intermediate between its ends.

2. The combination of a rotary compressor, a driving motor and regulating means therefor, a float located in a passage through which the fluid acted on by the compressor passes so as to float on the flowing fluid and respond to variations in its rate of flow, a-rod connected with said float and extending through the wall of said pas sage, a pivotally mounted beam to which said rod is connected at one side of the pivot. a weight on said beam for the purpose of initially balancing it under conditions of as to maintain any desired rate of flow, said my hand this Thirtieth day of September, beam hiving on it a scale for indicating the 1911. i rates 0 flow corresponding to various positions of said latter weight, and an opera- RICHARD RICE 5 tive connection between said beam and said Witnesses:

motor regulating'means. JOHN A. MCMANUS, J r.,

In witness whereof, I have hereunto set FRANK (x. HA'rrm.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents.

, Washington, D. 0.

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