US 2514223 A
Description (OCR text may contain errors)
M. covms GAS COMPRESSOR July 4, 1950 2 Sheets-Sheet 1 Filed June 14, 1946 n n n INVENTOR. MEYER COVINJ MudzLct a \iwzwfwova ATTORNEYS y 9 M. CQVINS 2,514,223
GAS COMPRESSOR Filed June 14, 1946 2 She ts-Sheet 2 ll Illlll Ill llllllll IN V EN TOR.
' M5 YER Comm/s lax 42mm a M ATTORNEYS III Patented July 4, 1950 UNITED STATES ENT OFFICE 1 Claim. 1
This invention relates to a compressor for compressing gases in an efiicient and economical manner.
It is an object of this invention to provide a compressor simple in construction in which the cylinder comprises a single piece cylindrical portion closed at each end by a head. Such a construction is advantageous, of considerable importance and is only possible by using my invention in which I provide a two-piece crank comprising a crank portion and a shaft portion and wherein the shaft portion is attached into the crank portion. Heretofore, compressors of this type have not been marketed because of the expensive design which resulted in the use of a single-piece crank necessitating a two-piece cylinder. A two-piece cylinder is expensive in design and construction and is more difficult to manufacture and maintain in tight condition during operation. A singlepiece cylinder is made possible by using a twopiece crank as I disclose herein. It is for this reason that for the first time a compressor of this type is a commercial reality.
It is another object of this invention to obtain good lubrication while at the same time preventing excess lubricating oil being discharged with the compressed gases. I, therefore, provide a novel lubrication system in which the lubricating oil is introduced along the shaft or the crankshaft and the rotation of the shaft works the lubricant into the cylinder. Any excess lubricant is then pumped out of cylinder by means of the piston action back to the lubricating source of supply. A minimum but sufficient amount of lubricant within the cylinder is thereby maintained. Lubrication of compressors has always been a difficult problem to solve. I have solved this problem by my system of lubrication.
It is a further object of this invention to provide a novel arrangement in the construction whereby an interconnected, double -headed and double acting piston is actuated by a two-piece half crank.
Still another object of this invention is to provide an improved arrangement of the inlet and outlet valves which result in a more efiicient compressor and which is necessary for compressing gases which are more difficult to pump efficiently than liquids.
It is also an object of the invention to provide a small compact compressor of large capacity which is economic to build and to operate.
A further object of the invention is to provide an arrangement of the actuating crank so as to take as little space as possible leaving more room for the piston thereby increasing the efiiciency several hundred per cent over other previous compressors of similar size.
Generally, my compressor comprises a cylinder constructed of asingle piece cylindrical portion closed at each end by a head, a double headed interconnected piston arranged to reciprocate in the cylinder, said piston having a slot in the center thereof with its longitudinal dimension at right angles to both the direction of reciprocation of the piston and to the axis of a crank, said crank comprising a. shaft portion and a crank portion, said shaft portion j ournalled in a bearing extending outwardly from a cylinder, said crank portion operatively associated in said slot for reciprocating the piston when the crank is turned.
The lubrication system comprises a lubricant source, means for introducing the lubricant along the shaft portion of the crank whereby the rotation of the shaft works the lubricant into the cylinder and a connection means for returning gases and excess lubricant back to the lubricant source and means associated with the lubricant sourcefor separating said gases, also returned with the lubricant, from the lubricant.
My compressor solves many problems involved in the compression of gases which are not found in the pumping of liquids. The problems are more difiicult and not as easily solved. It is more difficult to have efiicient tolerance between the piston and the walls of the cylinder and yet prevent excess leakage. It is more difiicult to lubricate and care must be taken to have proper inlet and outlet valves for emcient operation which is not so critical for a liquid pump.
The compressor in the present invention has many uses. One of the most important uses of my compressor is as a tractor pump wherein the crankshaft of the pump is attached to the power takeoff of the motor and used as an air compressor. It can also be attached to trucks and automobiles as a tire pump. It may also be used as an air compressor in filling stations and the like. The compressor is compact and efiicient so that it can be used as a portable compressor Wherever an air compressor is desired. The compressor may also be used as a source, of compressed air in spray guns, for spraying insects, fruit trees, paint and the like.
One of the big advantages of my compressor is that low friction loss permits the compressor to be driven by pulley and belt wherein previous compressors used for the purposes set forth above the high friction losses in such compressors necessitated a more positive drive such as a chain.
Other advantages, objects and uses of my compressor will become apparent by referring to the drawings in which Figure 1 is a side elevation partly in cross section showing the arrangement 0f the piston in the cylinder. The storage tank used in connection with the compressor is also shown.
Figure 2 is a perspective view of the piston.
Figure 3 is an end View of the compressor along: L5
the lines 33 of Figure 1.
Figure 4 is a sectional view taken in the -direc-- tion of the arrows along the line 44 of Figural. Figure 5 is a perspective view partly in cross section of the cylinder, piston andcrankarrangement.
Figure 6 is a more detailed view of the lubricant source means.
Figure 7 is a cap provided as shown in Figure 6 for permitting air to escape when the excess lubricant is returned to the lubricantsource-means.
Referring to the drawings, a single piece straight walled cylinder I isprovided; Around the cylinder are a plurality of fins 2 which'are an important feature in my invention to provide portion thereof which is at right angles to the direction of reciprocation.
A support 8 is provided to-which are-rigidly attached the end support members 9. The end support members 9 also serv as the heads for the single piece cylinder I. cylinder heads Q'are held in place tightly against the ends of cylinder I by means of the bolts II) which extend outside of the cylinder from one end support 9 to the other. Intake valves II of the tappet type are provided at each end of the cylinder head 9. Outlet valves 'of the ball and spring check type I2 are provided which allow the compressed air to pass through the discharge lines I3 into the storage tank I4; Apressure gauge I5 is ,providedjand an out-letline I6 is provided for connection to a device or apparatus which requires compressed gas.
One of the main features of my device is the two-piece crank II which is best shown in Figures 4 and 5. The two-piece crank I'I hasa shaft portion I8 and a crankvportion I9. The shaft portionls is screwed into the crank "portion I9 at point 20. A pulley wheel 21 is keyed to the shaft portion I8 by means of screw .32 and the slot 33. Thecrank portion I9 is adapted and ar- 5 ranged to rotate in the slot 1 of the piston thereby pro-yiding the means fonreciprocating the piston ,3 when the pulley wheel 2I is rotated. The shaft portion I8 is journalled in a sleeve bearing 22 which extends outwardly from the cylinder I as shown. A helical groove 23 extends circumferentially around the interior-"of the sleeve bearing 22 for the reason as will be hereinafter set forth in connection with the;'lubrication system. Lubrication of my device is obtained as follows:
The-end supports or 4.5
Lubricant source means 24 is provided and is screwed into a threaded tap 25. A lever 26 is provided which serves as a hand operated lever for starting the flow of lubricant into the system. Lubricant is introduced through the tap 25 and into the spaced grooves 23 causing the lubricant to work along the entire length of the shaft portion I-8 thereby providing lubrication for the crank. The rotation of the crankshaft forces the lubricant along the shaft I8 into the cylinder because of the helical groove 23 and the lubricant enters the cylinder and provides lubrication for the piston. However, it is essential that excess lubrication does not remain in between the piston heads 4 and 5 during reciprocation of the piston because some of the lubricant is bound to work out through the discharge valves I2. Therefore, a connection 26 in the bottom of the cylinder I is provided and the reciprocation of the piston ,forces the excess lubricant as Well as some compressed gas through the connection 26, th line 21 back into the lubricant source 24. The lubricant source 24 has a separating chamber 25. In chamber 25 the compressed gas, so returned along with the excess lubricant, is separated from the lubricant and the gas is withdrawn through the cap-28 provided with an opening 29 which connectswith the. interior of the separating chamber 25 and the atmosphere. Thus I have provided a recycling system for lubrication of my compressor which provides sufiicient lubrication without permitting excess lubricant to accumulate in the cylinder which would result in the discharge of the excess lubricant through the exhaust valves.
The intake valves II work in the exhaust port 30 in the heads 9. To prevent foreign matter from entering the cylinder, screens 3I are provided. The pulley wheel 2| may be driven by means of a belt and any suitable source of power may be used.
My compressor may be constructed of any suitablemetal to accomplish the purposes set forth herein and the type of metal selected forms no part of my invention.
I claim as my invention:
In a compressor the combination of a horizontal cylinder, said cylinder comprising a, single piece cylindrical portion closed at each end by a vertical head, a double headed interconnected piston adapted and arranged to reciprocate in the cylinder and having a slot in the center thereof with its longitudinal dimensions at right angle to the direction of reciprocation, a half crank adapted and arranged for reciprocating said piston in said cylinder comprising a shaft portion and a crank portion, said crank portion adapted and arranged and operatively associated in said slot in such a. manner as to cause reciprocation of the piston when the crank is turned, the shaft portion of said crank journalled in a sleeve bearing extendout outwardly from said cylinder, means for turning the shaft portion of said crank, and means for lubricating said crank and said piston comprising a lubricating source means, a plurality of spaced grooves within said bearing and extending circumferentially around the interior of said bearing, means for introducing a lubricant from said source through said bearing into said shaft portion whereby the rotation of said shaft portion works the lubricant along said shaft portion toward the interior of the cylinder thereby lubrieating the interior of the cylinder, and means for returning the excess lubricant in the bottom of said cylinder to the lubricating source comprising a connection fronrthe bottom of the cylinder to the lubricating source, whereby the piston forces compressed gas and said excess lubricant through said connection, and means for separating said compressed gas from said excess lubricant in the lubricating source means.
REFERENCES CITED UNITED STATES PATENTS Number The following references are of record in the 19 Number file of this patent:
Name Date Bailey Oct. 11, 1898 Hanna Nov. 8, 1910 Smith, et a1 Dec. 6, 1932 Mantle Apr. 21, 1942 Hewitt, et a1 Mar. 11, 1947 FOREIGN PATENTS Country Date Switzerland Mar. 14, 1917