Double acting type compressor

A double acting type compressor comprising:

• a main body including a cylinder block having at least one cylinder bore axially extending therethrough and a pair of cylinder heads secured to opposite ends of said cylinder block;
• at least one double headed piston received within said at least one cylinder bore for reciprocating motion therein;
• a pair of suction chambers formed in said main body at opposite ends thereof, at least one of said suction chambers being disposed to be supplied with compression medium from outside;
• a suction passageway formed in said main body and communicating said suction chambers with each other;
• a pair of discharge chambers formed in said main body at said opposite ends thereof;
• a discharge passageway formed in said main body and communicating said discharge chambers with each other;
• a discharge port formed in said main body for allowing said compression medium to be discharged to the outside therethrough, said discharge port extending through one of said discharge chambers;
• communication means communicating said discharge port substantially directly with said discharge passageway;
• a pair of pulsation attenuating means interposed between said discharge chambers and said discharge passageway, each of said pulsation attenuating means having a multiplicity of small through holes formed therein, said small through holes communicating a corresponding one of said discharge chambers with said discharge passageway, said small through holes of each of said pulsation attenuating means having a substantially reduced total cross-sectional area relative to the cross-sectional area of said corresponding one of said discharge chambers so as to impart increased flow resistance to said compression medium passing said small through holes;
• said discharge passageway having a substantially large cross-sectional area relative to the total cross-sectional area of said small through holes of each of said pulsation attenuating means;
• said discharge port communicating with each of said discharge chambers solely through said communication means, said discharge passageway and a corresponding one of said pulsation attenuating means;
• a pair of valve plates interposed between said cylinder heads and said cylinder block, each of said valve plates having a discharge through hole formed therein, said discharge through hole of each of said valve plates communicating a corresponding one of said discharge chambers formed within said cylinder heads with said discharge passageway axially extending through said cylinder block;
• a pair of valve sheets interposed between said cylinder block and said valve plates, said small through holes of said pulsation attenuating means being formed in each of said valve sheets at a location facing said discharge through hole formed in a corresponding one of said valve plates;
• said communication means comprising a first through hole formed through one of said valve plates corresponding to said one of said discharge chambers and a second through hole formed through one of said valve sheets corresponding to said one of said discharge chambers, said first and second through holes being aligned with said discharge port;
• and
• a gasket interposed between one of said cylinder heads within which said one of said discharge chambers is formed and said corresponding one of said valve plates;
• said communication means further including a third through hole formed through said gasket and aligned with said discharge port;
• whereby the total quantity of said compression medium discharged into said discharge chambers is caused to flow through said small through holes of said pulsation attenuating means into said discharge passageway, to thereby substantially attenuate pulsations of said compression medium and to reduce noise