US2469714A

US2469714A - Spill port control for free-piston units

Info

Publication number: US2469714A
Application number: US550877A
Authority: US
Inventors: Kenneth C Cooper
Original assignee: United Aircraft Corp
Current assignee: Raytheon Technologies Corp
Priority date: 1944-08-23
Filing date: 1944-08-23
Publication date: 1949-05-10
Anticipated expiration: 1966-05-10

Description

May 10, 1949. K. c. COOPER SPILL PORT CONTROL FOR FREE-PISTON UNITS Filed Aug. 23, 1944 2 Shets-Sheet 1 wv NV vv ON INVENTOR- on 0N y 1949. K. c. COOPER 2,469,714

SPILL PORT CONTROL FOR FREE-PISTON UNITS Fi led Aug. 25, 1944 2 Sheets-Sheet 2 'IIJ'IIA'I A i\\ 3 &

INVENTOR Fla. 2 M

Patented May 10, 1949 UNITED STATES PATENT OFFICE SP LL P RT EBEE QBEIQN Kenneth G. @ooper, lortland, Goran assignor at!) United Aircraft florporation, 'East Hartford, .flnnrn, a cnrpnrafinn of Delaware pplica ion Aus 3, Se ia No.- 559,

8 *UIaims. 1

August 23 1 9 new Patent No. '2,4=4=1;272, in i wh ch he spaced en s of the h nd are held ta- .get er'by a pr ng to keep the be d t ht on the cylinder. A Iea h e o th s invent on is a sel sealing band. which does not require a spring to maintain th han i her seal e position Another Ieature is a sealing band which surrounds thecylinder andis guided by an overlying stationary ring which has ports in, line with the ports in the compressor cylinder.

A f at re of t i ve tio s a ightwe ght st u urec n oll th sp ll por s w ch will require little power for adjusting it; and which will occupy a small space.

Other objects and advantages will be apparent from the specification and claims, and from the cc m ny n d gs which llust ate n e hodiment of the invention.

Fig. l is a sectional view through *the freepiston unit.

Fig.2 is a sectional view.on .line 2-2 of Fig.

Fig, 3 is a fragmentary View on line iii-m3 of Fi The unit shown includes aneng-ine cylinder I having reciprocating pistons 12, and M to which iconipressor pistons l6 and 1.8 in cylinders 2,0 and 22 are integrally connected. Sleeves 2.4 and 38 attached to the compressor pistons complete the reci r t ng piston blies sleeves si :eombinatien with stationary pistons 28 and .30 riorni air spring cylinders.

The piston assemblies are moved apart by the burning of .fuel injected into eengine cylinder 110 thro gh one. or m ozzle 32- .A ompresse in the air spr ng c inders en the p wer strok returns the pistonassemblies. "Theassemblies are always maintained at "equal distances from the cent r of the engine cylinders by :a linkage. not shown.

Intake manifold 42, which extends around the compressor and engine cylinders conducts air to intake valves 44 in the *heads of the compressor cylinders, through which air alternately enters opposite endsof the cylinders. The compressed air "leaves the cylinders through discharge valves '46, also at opposite ends of the compressor cylinders and passes "into a central scavenge chamber-48 and end chambers 50 and 52. These chambers may be interconnected by a scavenge manifold, not shown.

Gompressed air from the scavenge chambers 'en'tersengine ports 54 and-56 which-areuncovereel 'bypiston 2 and *l 4 at the 'end'o f the-power stroke, thereby permitting air to be blown through the engine cylinder. Gas and air in the engine cylinders is discharged through exhaust ports 58 into exhaust manifold '69.

Each compressor cylinder has one or more axially spaced rows of spill ports 62 to permit discharge of air without compression from the cylinder. Each row of ports maybe individually controlled by a band -54, Fig. '3, extending around the cylinder between projecting ribs 66 extending from the cylinder, and having spaced openings .68, Fig. 2, fQI' alignment with the "spill ports. Band '64 is relatively thin and is supported by a in 9 xte ing a ound he cy i e u si e of'the band and having spaced openings llwhich are n line ith the s ll po t :R n 0 may "be held posi n twe n the adjac nt pr tin ribs 66 thy clamping wires 14- fitting in grooves 16 i the rojecting ri s E ch g is nou large then band 4 so hat the band is fr to move "be we n the outer periphery o t e compre ser cylinder and he surroundin r n Band 4 may have vpmie t hg lugs 18 01.1919.- zpositi ends fittingin notch s B0 in. a ear block tzlece'ted b tween opposite ends f th rl n fine T e r block permits the band to be mov d .circumie entially or ali ning the openings in the h nd with the p rts .in the cylinder- .Ass ewn, thehleehhas. areck .84 enga in witha pinion- '6 eh a ha' t L88 parallel to the axis of the compressor c linder, Rotat on of pinion. .96 will i. nst hand 54. fllhe structure by which the pini n. is wired. not being partior this invention. will not e described in detail,

Ihelugs '18 iii; i eely in s a block 82 to permit the hand lit tomove into engagement with the cy inder wa wh n th pressure in e cylinder is le s than the .ext rna pr ssure. If the pressure in the cylinder is higher than the surrounding pre ure. the hand may mo e against the su rounding ring when the band is in ports closing position. In either case the band seals the ports '65 against leakage without the necessity for a tensioning spring to hold the band on the cylinder.

It is to be understood that the invention is not limited to the specific embodiment herein illustrated and described, but may be used in other ways without departure from its spirit as defined by the following claims.

I claim:

1. A free-piston engine-and-compressor unit including a compressor piston and cylinder, said cylinder havin at least one circumferential row of spill ports therein, a band extending circumferentially around said cylinder and being movable on said cylinder into a position to cover the ports, and a ring extending around the cylinder and overlying the band to form a channel in which the band may move, said ring having ports aligned with the ports in the cylinder, and said band having ports movable into and out of alignment with the ports in the cylinder and ring.

2. A free-piston engine-and-compressor unit including a compressor piston and cylinder, said cylinder having at least one circumferential row of spill ports therein, a band extending circumferentially around said cylinder and being movable on said cylinder into a position to cover the ports, and a ring extending around the cylinder and, overlying the band, said ring having spaced ports aligned with the cylinder ports, said band having spaced openings therein corresponding to the spacing of the spill ports and being movable circumferentially between said cylinder and ring for opening or closing the spill ports.

3. A free-piston engine-and-compressor unit including a compressor piston and cylinder, said cylinder having at least one circumferential row of spill ports therein, a band extending circumferentially around said cylinder to cover the ports, said cylinder having guide means thereon on opposite sides of the row of ports for guiding the band for circumferential movement, and a ring extending around the cylinder and overlying the band, said ring being connected to said guide means and having ports aligned with the ports in the cylinder, and said band having spaced ports adapted for alignment with the cylinder 1 and ring ports by movement of the band circumferentially between the ring and cylinder.

4. A free-piston engine-and-compressor unit including a compressor piston and cylinder, said cylinder having at least one row of spill ports therein, means on the cylinder for forming with said cylinder a circumferentiall extending guide channel overlying said row of ports, and a band movable circumferentially in said channel for opening and closing said ports, said band having openings therein which are moved into and out of alignment with the ports, said means having ports aligned with the cylinder ports.

5. A free-piston engine-and-compresso-r unit including a compressor piston and cylinder, said cylinder having at least one circumferential row of spill ports therein, a band extending circumferentially around and movable on said cylinder to cover the ports and a ring extending around the cylinder and overlying the band, said ring having openings therein aligning with the spill ports in the cylinder and said band having openings movable into and out of alignment with the ports in the cylinder and with the openings in the ring by movement of the band on the cylinder.

6. A free-piston engine-and-compressor unit including a compressor piston and cylinder, said cylinder havin at least one circumferential row of spill ports therein, a band extending circumferentially around said cylinder and being movable on said cylinder into a position to cover the ports, and a ring extending around the cylinder and overlying the band to form a channel in which the band may move, said band having spaced ports corresponding in spacing with the cylinder ports for alignment with the cylinder ports, said band being movable on the surface of the cylinder for alignin the ports, said ring being constructed and arranged to provide for fiow of fluid into and out of said cylinder when said ports in the band and cylinder are in alignment.

7. A free-piston engine-and-compressor unit including a compressor piston and cylinder, said cylinder having at least one circumferentially extending row of spill ports therein, a band extending circumferentially around the cylinder and being movable on the cylinder to close the ports, said band having ports movable into and out of alignment with the cylinder ports, guide means on the cylinder on opposite sides of the ports for guiding the band and a guide overlying the band and spaced from the cylinder to permit movement of the band between said guide and cylinder, said guide having ports aligned with the cylinder ports and being supported in position by said guide means.

8. A free-piston engine-and-compressor unit including a compressor piston and cylinder, said cylinder having at least one circumferentially extending row of spill ports therein, a band extending around said cylinder to cover the ports, guide means on the cylinder on opposite sides of the ports for guiding the band and a ring extending around the cylinder and overlying the band, said ring having ports aligned with the cylinder ports and being supported in overlying relation to the band by said guide means, said band having open ings therein which are moved into and out of alignment with the .ports, said band having a projecting lug by means of which the band is moved, the ends of the ring being spaced to accommodate the lugs.

KENNETH C. COOPER.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 877,492 Doelling Jan. 28, 1908 1,481,358 Dwyer Jan. 22, 1924 1,579,782 Riesner Apr. 6, 1926 2,016,613 Pescara Oct. 8, 1935 2,038,442 Pescara Apr. 21, 1936 2,064,976 Janicke Dec. 22, 1936 2,090,709 Steiner Aug. 24, 1937 2,108,890 Janicke Feb. 22, 1938 2,139,425 Steiner Dec, 6, 1938 2,147,935 Steiner Feb. 21, 1939 2,426,311 Ledwith Aug. 26, 1947 2,441,272 Kalitinsky May 11, 1948 2,441,273 Kalitinsky May 11, 1948 FOREIGN PATENTS Number Country Date 237,170 Germany 1910