US2142187A

US2142187A - Centrifugal compressor

Info

Publication number: US2142187A
Application number: US102931A
Authority: US
Inventors: Emery C Furrer
Original assignee: Individual
Current assignee: Individual
Priority date: 1936-09-28
Filing date: 1936-09-28
Publication date: 1939-01-03
Anticipated expiration: 1956-01-03

Description

7 Jan. 3, 1939. E. c. FURRER CENTRIFUGAL COMPRESSOR Filed Sept. 28, 1936 VINVENTOR EMERY c. FURRER.

ATTORNEY Patented Jan. 3, 1939 UNITED STATES PATENT OFFlCE 6 Claims.

This invention relates to improvements in centrifugal compressors.

One object of the invention is to provide a centrifugal or turbo compressor for gases which is so constructed as to effect a reduction in energy losses between stationary and moving parts by means of fluid seals between such parts.

Another object of the invention is to provide a centrifugal compressor having preferably a plurality of radially disposed spaced apart compression chambers each of which is cooled by air moved between the same by the rotary movement of the chambers.

A further object of the invention is to provide a rotary compressor arranged to draw the air, or other gas to be compressed, into the machine in opposite axial directions to effect a mutual counter-balancing of the rapidly flowing incoming gases to reduce or eliminate shock losses caused thereby.

Other objects of the invention relate to various features of construction and arrangement of parts which will be apparent from a consideration of the following specification and accompanying drawing wherein:

Figure 1 is a side elevation of a centrifugal compressor embodying the present improvements.

Figure 2 is an enlarged sectional View taken on line 22 of Figure 1.

Figure 3 is a further enlarged broken vertical section taken on line 3-3 of Figure 2.

Figure 4 is an enlarged broken vertical sectional view taken on line 44 of Figure 2.

Figure 5 is an enlarged section taken on line 5-5 of Figure 3.

In Figure 1 of the drawing, the apparatus shown is mounted adjacent a wall Ill of a building for support thereby and is provided with two inlet ducts H and 2 for conveying to the compressor the air to be compressed. It will be understood that one or both such ducts may be connected to a supply of other gas where such other gas is to be compressed by the machine.

The duct l connects at its inner end to a hollow shaft I3, see Fig. 3, which shaft is supported by upper and lower bearings l4 and I5. The shaft i 3 is also provided with a pulley l6 around which operates a belt ll extending to an electric motor It or other source of power for effecting the rotation. of the shaft. The duct I2 is of considerably greater diameter than duct H and bearing I5 is supported therein by any suitable means as by beam I511.

Extending from the hollow shaft I3 are a plurality of radially disposed compression chambers I 9 which decrease in cross sectional area from the inner to the outer ends thereof. The chambers l9 are spaced apart to provide passages for the flow of cooling air around the chambers and are provided with heat radiating or cooling fins l9a.

The upper and lower ends of the shaft l3 are provided with blades 20 which are somewhat fan shaped and which are shaped at their edges to move the air from the ducts H and i2 inwardly toward a centrally arranged deflecting plate 2|. The blades also provide a structural support for the shaft I3, the inner ends of the blades being united to a central shaft or core. 22. Itwill be observed that as the shaft I3 rotates, air will be drawn from the ducts l l and I2 inwardly through each end of the shaft toward the deflector plate 2| which directs the air radially into the various compression chambers l9. Due to the decreasing cross sectional area of the chambers is, the air is compressed under the influence of the centrifugal force developed by the rapidly rotating chambers and passes from the chambers into a hollow rim or annular connecting member 23 which unites the chambers at their outer ends.

As is shown in Fig. 2, the portions 23a of the rim 23 between adjacent arms decrease in cross sectional area from the forward ends to the rear ends thereof, the structure being designed for rotation in a counter-clockwise direction as viewed in Fig. 2. Air in passing from the chamhers I!) into the Various rim sections 23a is consequently further compressed and passes from the rim into air receivers 24, two of which are shown, which terminate in ducts 25 which convey the compressed air to a place of storage or use. The receivers 24 are stationary and decrease in cross sectional area from the outlet ends which are connected to the conduits 25.

The rim sections 23a preferably are provided with a number of spaced apart walls or partitions 23b between which the air passes in flowing from the ends of the chambers l9 into the receivers 24.

The hollow rim 23 is, as shown in Fig. 4, provided on its upper surface with three

annular walls

21, 28 and 29, the first two of which are shown as being slightly curved at their extremities. Each receiver 24 is provided with a neck 24a, which is somewhat enlarged at its inner periphery and terminates in a horizontal wall 241) which is provided with oppositely curved depending annular walls 30 and 3]. It will be seen that between walls 21 and 28 a chamber 32 is provided in which sealing liquid may be retained and which in cooperation with the walls 21 and 30 will pro- Vide a seal to prevent the escape of compressed air through the space between the outer periphery of the rim and the adjacent portion of the receiver.

Between

walls

28 and 29 another chamber 33 is provided for retaining sealing liquid which in cooperation with walls 28 and 3| will provide a further seal against the escape of compressed gas. The rim is also provided with depending

walls

34 and 35 which project into the spaces or liquid chambers defined by

walls

36, 31 and 38 which are carried by the necks 24a of the receivers 24. The lower extremities of the

walls

34 and 35 are shown as being provided with thin plates 39 which extend into close proximity with the walls 40 which connect the

walls

36, 31 and 38 to break up and reduce eddy currents in the liquid during the rapid rotation of the compressor.

It will be apparent that the thin plates 39 will wear away readily should they contact the wall 40 and that the plates therefore can be set initially close to the wall 40 without subsequent damage to the parts should they contact during operation. It will be noted that while the upper and lower fluid seals shown in section in Fig. 4 are similar in principle, they differ slightly in structural detail for the reason that the fluid of the upper seal is carried by the rotary structure, while the fluid of the lower seal is carried by members supported by the stationary receivers.

It will be observed that as the rotary structure of the compressor is operated air will be drawn into the ducts H and I2 partially by the fan action of the blades 20 and partially by the centrifugal action of the air initially present in the structure. The air will move radially through the compression chambers l9 and be compressed as it is forced to travel by centrifugal action through the constantly reduced cross sectional area of the chambers. It then passes from the chambers into the rim sections between the walls 23b thereof and is thence directed between blades 24c disposed in the neck 24a of the receivers 24. The stationary blades 240 are so disposed as to effect a reaction on the air issuing from the rim and converts the velocity head into pressure head as it passes into the receivers 24.

During such rotation of the apparatus the liquid in the respect ve sealing chambers tends to move rad ally outward y or to the left as view d in F gure 4 by the centrifugal action of the machine and will assume substantiallv the positions indicated in Fig. 4 in which positions it will be noted that compressed air cannot escape between the rim and the receivers. The greater the back pressure of the air due to centrifugal action, the greater will be the resisting force exerted by the liquid. The fluid sealing means described not only provides an adequate seal between the relatively movable parts of the apparatus, but greatly reducesenergy losses due to friction. V

The chambers I 9 are provided on their outer walls with horizontal blades 4| as shown in Fig. 5.

which are shaped to produce an inward flowof air through the duct l2 and upwardly into heat transfer relation with the surfaces of the chambers l9 and the fins l9a to absorb the heat of compression generated by the compression of the air. Stationary vanes 42 preferably are secured to the interior of the duct l2 to deflect the air in the direction of rotation of the chambers to reduce shock.

To avoid the transfer of heat to the duct l i from the rising air a sheath 43 is provided around the duct as shown in Figs. 1 and 3.

In operation the compressor is operated at the velocity required to effect the desired compression of the air or the other gas. Due to the dual intake arrangement whereby the incoming air flows in opposite direction through the equal capacity intake ends of the shaft I3 to the center of the machine toward the distributor plate 2|, the shock or thrust of the incoming air is balanced at all speeds of operation. It will also be noted that increasing the rotary velocity of the machine to increase its output of compressed air or the degree of compression thereof, increases also the flow of air around the exterior of the compression chambers to absorb the increased heat of compression and that increase in back pressure due to velocity, which tends to effect escape of air between the annular rim 23 and the annular receivers increases the resistance of the fluid in the sealing chambers to resist such tendency;

It will be understood that if a gas other than air is to be compressed, the duct H and the thereto axially of the structure and in opposite directions, radially disposed rotary compression chambers communicating with said intakes and provided with passages for the flow of cooling air between adjacent chambers, and a stationary receiver for receiving gas compressed by the chambers and provided with an elongated arcuate intake disposed in communication with the outer ends of said chambers, said receiver having cross-sectional areas increasing progressively in the direction of rotation of said chambers.

2. A gas compressor comprising a rotary structure, means for rotating the same, said structure having an axial gas intake and radially arranged compression chambers communicating therewith for centrifugally compressing gas flowing into the same, a gas receiver having an elongated arcuate intake communicating with the ends of said chambers, and means for effecting the flow of air axially of the structure between said chambers for absorbing the heat of compression of the gas therein. 7

3. A gas compressor comprising a rotary structure having an axial gas intake, a plurality of radially arranged rotary gas compression chambers communicating therewith, an annular hollow rim communicating with and connecting the outer ends of said chambers and provided with an open outer periphery, the segments of said rim between adjacent chambers decreasing in cross sectional area from the forward to the rear ends of said segments, a stationary gas receiver disposed adjacent the outer open periphery of saidrim for receiving gas therefrom, and inter-leaving projections carried by adjacent portions of said rim and receiver defining annular fluid-confining channels for a fluid to prevent escape of gas in the passage of the same from said rim to said receiver.

4. A gas compressor comprising a rotary structure having an axial gas intake, a plurality of radially disposed rotary chambers communicating with said intake, a hollow rim connecting the outer ends of said chambers and communicating therewith, said chambers from the inner to the outer ends thereof and the sections of said rim between adjacent chambers from the forward to the rear ends thereof decreasing in crosssectional area for effecting the compression of the gas forced centrifugally therethrough, and a stationary gas receiver communicating with said rim.

5. A gas compressor comprising a rotary structure provided with a hollow shaft disposed axially of the structure and provided with a gas intake at each end thereof, a plurality of spaced apart radially disposed compression. chambers communicating with said shaft, a hollow rim con nected to and communicating with the outer ends of said chambers and provided with an open outter periphery, stationary annular receiving means communicating with the open periphery of said rim, fluid sealing means comprising cooperating stationary and rotary portions carried respectively by said receiving means and said rim, to prevent escape therebetween of cornpressed gas, and blades carried by said chambers for effecting the circulation of air between the latter for absorbing heat generated by the compression of the gas therein.

6. In a gas compressor, a rotary structure comprising a plurality of radially arranged compression chambers decreasing in cross sectional area from the inner to the outer ends thereof for compressing gas passing therethrough, said structure being provided with an axial gas intake common to said chambers, an annular sta tionary gas receiver having a gas receiving passage in its inner periphery, and a continuous hollow rim at the outer ends of said chambers provided with an outer annular outlet in sealed communication with the gas receiving passage of said receiver for transferring compressed gas from said chambers to said receiver.

EMERY C. FURRER.