Patent ID: 9074591
Filing Date: 2015-07-07
Classification: F04B

Abstract:
1. A compressor comprising: a hermetic container storing therein a lubricant, an electric element including a stator and a rotor, and a compression element driven by the electric element, the compression element including a crankshaft including a main shaft portion having the rotor fixed thereto, and an eccentric shaft portion, a bearing portion pivotally supporting the main shaft portion, a cylinder block having a cylinder bore formed therein, the cylinder bore including a cylindrical portion and a tapered portion, a piston that reciprocates inside the cylinder bore, a joining portion connecting the eccentric shaft portion and the piston, and a screw hole section, wherein a cylinder head is coupled to the cylinder block by a bolt which extends through the screw hole section which penetrates the cylinder block and the cylinder head, wherein the screw hole section includes: a first screw hole section having a first diameter which engages threads of the bolt; a second screw hole section having a second diameter which is larger than the first diameter and a diameter of the bolt in the second screw hole section; and a third screw hole section having a third diameter smaller than the second diameter, wherein the second screw hole section having the second diameter is disposed between the first screw hole section having the first diameter and the third screw hole section having the third diameter, and wherein a boundary between the first screw hole section and the second screw hole section is substantially at a boundary between the cylindrical portion and the tapered portion.