US1199515A - Air-compressor. - Google Patents

Description

E. WlKl.

AIR COMPRESSOR, APPLICATION FILED 05c. 16, 1911.

1 1 99,5 1 5 Patented Sept. 26, 1916.

2 SHEETS-SHEET 1.

A TTORNE Y E. WIKI.

AIR COMPRESSOR.

APPLICATION FILED DEC. 16. 1911.

1 ,1 99,5 1 5 Patented Sept. 26, 1916.

2 SHEETS-SHEET 2.

//IIII IIIIIII/ IN VE N TOR WITNESSES Mbk/Q 5M $75 5y I if, 72 M dc gw EDWARD WIKI, 0F LUCERNE, SWITZERLAND.

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Application filed December 16, 1911.

To all whom it may concern:

Be it known that I, EDWARD WIKI, a citipressors and consists in novel provisions made for the purpose of maintaining a substantially constant pressure in the reservoir passage or chamber into which the pump discharges without varying the speed of the compressor.

By the term air compressor used herein I mean to include reciprocating or rotating compressors, pumps, blowers, or the like, adapted for moving a gaseous fluid.

The object of my invention is to provide simple and effective means of the kind and for the purpose specified adapted to control the pressure at the discharge end of the compressor by cutting off the admission to thecompressor ofthe fluid to be compressed whenever the delivery pressure rises above a predetermined value.

The various features of novelty which characterize my invention are pointed out with particularity in the claims annexed to and forming a part of this specification. For a better understanding of the invention, however, and the advantages possessed by it, reference should be had to the accompanying drawings and descriptive matter in which I have illustrated and described a preferred form in which my invention may be embodied.

Of the drawings, Figure 1 is an elevation, partly in section, of a portion of a reciprocating air compressorprovided with my improved pressure regulating means. Fig. 2 is a partial sectional plan taken on the line 22 of Fig. 1. Fig. 3 is a sectional elevation taken on the line 33 of Fig. 2. And Fig. 4 is a sectional elevation of a portion of the apparatus shown in Fig. 1, on a larger scale than Fig.1.

In the drawings, A, represents a reciprocating air compressor of common form.

A represents the inlet passage through which the air to be compressed passes to the compressing cylinder, and A represents the Specification of Letters Patent.

bottom of the cylinder C Patented Se t. 26, 1916.

Serial No. 666,168.

connection through which the compressed airis discharged.

To the end of the passage A is secured a cylindrical valve casing C in which is mounted a rotary valve comprising a hub D and a cylindrical shell formed with ports D adapted to be moved into and out of register with the ports C formed in the wall of the casing U. The valve D is secured to a shaft D journaled in the valve casing U and with one end extending through the outer end of the casing. To the external end of the shaft D is securedan operating arm D The valve casing C is formed with armlike extensions C and C The extension 0 isformed with a cylinder C A piston E working in the cylinder C has connected to it a piston rod E which is slidinglyreceived in the arm C or rather, as shown, in the hollow bolt F adjustably mounted in the arm 0*. The valve operating arm D is connected to'the rod E between the arms C and C As shown, the arm D passes through an opening formed in an enlargement E of the rod E. A light helical spring F surrounding the piston rod E, acts between the spring abutments F and F which engage the adjacent ends respectively of the piston rod enlargement E and the tubular member F This spring tends to hold the valve D in the position shown in the drawings in which the ports 0 andD are in register and the piston E engages the An arm Gr secured to the casing arm O forms a stop to limit the upward movement of the piston rod E to the amount required to move the ports D out of register with the ports C. It should be explained that the function of the light spring F is simply to insure the return of the'piston E and the valve D to the position occupied by them in the drawings and it is not the purpose of this spring to hold the piston E and the valve D connected to itin an intermediate position. In the form shown, where the piston E is vertically movable and moves up to move the valve-member D into position to close the ports C, the spring supplements the action of the weight of the piston E and, if the latter is heavy enough, may be omitted.

To move the valve member D into position to close the ports C when the pressure at the delivery side of the chamber rises above a predetermined value, a device responsive to the delivery pressure, is employed to control the flow of a pressure fluid to the lower end of the cylinder C As shown, this pressure responsive device comprises a member H provided with a chamber H closed at its upper end by a flexible diaphragm I, secured to the member H by a washer H and bolts H As shown, the head of one of these bolts is slotted at H? to receive one end of a lever K pivotally connected to the bolt head by the pivoted pin K and the head of the diametrically opposed bolt H is slotted to receive and guide the lever and carries at its outer end an adjustable abutment screw K limiting the rising movement of the lever. The diaphragm 1 hassecured to it a member J, the upper end of which is tapered and engages the seat K formed for the purpose on the lever K. The lower end of the member J extends'into the chamber H and is shaped to form a valve controlling the outlet port H from the chamber. A pipe L connects the outlet passage H to the lower end of the cylinder C and a pipe N connects the chamber H to the outlet passage A of the compressor. A weight K adjustably secured on the arm K, with the latter, forms a loading device for holding the member J in position to close the port H except when the reservoir or discharge pressure of the pump exceeds a predetermined value. When this predetermined pressure value is exceeded the fluid pressure in chamber H acting upwardly on the diaphragm 1 causes the valve J to open the port H thus permitting air to pass from the chamber H to the lower end of the cylinder C whereupon the piston E at once moves upward the full amount of stroke permitted it and shifts the member D from the wide open. position to the fully closed position. The valve member D is held in its closed position until the diminution in pressure in chamber H permits the closure of the port H When this occurs the valveD is quickly returned to its wide open position by the weight of the piston E and the action of the spring F. To permit this provisions are made for a constant though restricted escape of air from the cylinder C and the pipe L. With the construction shown some leakage will take place out of the lower end of the cylinder C through the clearance space between the piston E and the cylinder-wall and this is supplemented as shown by the leakage through the leakage passages H and may be supplemented also by a restricted discharge permitted through the valve 0 secured to the lower end of the cylinder C The leakage through the leakage passages H may be regulated as desired through the needle valve M.

Those skilled in the art will understand that the mechanism shown forms a simple and eflective apparatus for regulating the operation of air compressors operating at a fairly constant speed and which it is desired to have maintain a substantially constant .delivery pressure.

The aggregate area of the ports C and of the ports D should be large enough so that when the valve D is in the wide open position there will be no wire drawing of the fluid to be compressed in passing through said ports. In practice, the aggregate crosssectional area of each of these sets of ports is ordinarily at least as large as the crosssection of the passage A. The valve D is entirely balanced so far as the action of the fluid passing through the ports D is concerned, and may be so constructed that but little force is required to move it, especially as when it is in the closed position it need not absolutely seal the port C, since a r estricted leakage through these ports is without material eflect upon the operation of the compressor. When the ports C are thus closed the compressor delivers little or no compressed fluid and hence requires ractically no power to operate it at its normal speed, as is desirable.

One advantage ofthe pressure responsive device is that the lift of the valve J may be very small say one-tenth or even one-twentieth of an inch.

While in accordance with the provisions of the statutes I have illustrated and described the best form of my invention now known to me, it will be apparent to those skilled in the art that changes may be made in the form of the apparatus disclosed without departing from the spirit of my invention, and that under some conditions certain features of my invention may be used with advantage without a corresponding use of other features.

Having now described my invention what I claim as new and desire to secure by Letters Patent is:

1. In combination with a pump of the kind described, a normally open balanced valve controlling the inletpassage of said pump, and an operating mechanism therefor, adapted to move said valve into its fully closed position when the delivery pressure rises above a predetermined value, and to move the valve into its wide open position when the delivery pressure falls to or below said predetermined value, said mecha nism including a fluid. pressure supply conduit, a second valve, and a fluid pressure de-, vice connected to said conduit through said second valve and adapted to move said balanced valve into its wide open position whenever said second valve is opened, leakage provisions permitting a restricted but constant escape of pressure fluid contained in said device to permit the closure of said balanced. valve when said second valve is closed, and pressure responsive means for opening and closing said second valve when the delivery pressure rises above and falls to said predetermined value.

2. In combination with a pump of the kind described, a normally open rotary valve controlling the inlet passage of said pump and an operating mechanism therefor, adapted to move said valve into its fully closed position when the delivery pressure rises above a predetermined value, and to move said valve into its wide open position when the delivery pressure does not exceed said value, said mechanism including a chamber connected to the delivery end of the pump, a second valve, afluid pressure actuating device for said rotary valve connected to said chamber through said second valve and adapted to entirely close said rotary valve when said second valve is open, leakage provisions permitting a constant but restricted escape of fluid from said device, and means responsive to the pressure in said chamber for opening said second valve when the delivery pressure rises above a predetermined value, and for closing said second valve when the delivery pressure does not exceed said value.

3. In combination with a pump of the kind described a balanced valve controlling the inlet passage of said pump, a fluid pressure device adapted on the admission of a pressure fluid thereto to close said valve, and comprising a cylinder, a piston Working therein and connected to said valve and means lightly tending to hold said piston and valve in the wide open position of the latter, a chamber connected to the delivery end of said pump and having an outlet connection leading to sald cylinder, and leakage provlslons permitting a restricted but constant escape of the fluid under pressure contained in said cylinder and outlet connection, a second valve controlling said outlet connection, and operating provisions therefor responsive to the pressure in said chamber.

4. In combination with a pump of the kind described a rotary valve controlling the inlet passage of said pump, a cylinder, a piston working therein and connected to said valve, means lightly tending to hold the piston and valve in the wide open position of the latter, a chamber connected to the delivery end of said pump having a flexible diaphragm forming a portion of its wall and having an outlet connection leading to said cylinder, a valve secured to said diaphragm and controlling said outlet connection, an adjustable external loading device for the diaphragm, and leakage provisions permitting a restricted but constant escape of the fluid under pressure contained in said cylinder and outlet connection.

5. In combination with a pump of the kind described a valve controlling the inlet passage of said pump and operating means therefor adapted to shift the valve between its wide open and its fully closed positions on a slight variation in one direction or the other of the delivery pressure from a desired maximum delivery pressure without maintaining the valve in an intermediate throttling position, said means comprising a pressure chamber and a pilot valve responsive to the delivery pressure controlling the pressure in said chamber.

EDWARD WIKI. Witnesses:

C. FIsHER, J ULIUs HARTMAN.

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

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