A hermetic compressor comprising: a cylinder whose inner circumference is elliptical and forms a compression chamber; a first bearing and a second bearing provided on both sides of the cylinder and forming a compression chamber together with the cylinder; a roller that is attached to a rotating shaft supported by the first and second bearings (310, 320), is eccentric to the inner circumference of the cylinder, and varies the volume of the compression chamber while rotating; and a vane (351, 352, 353) that is inserted into the roller, rotates with the roller, and is pushed out toward the inner circumference of the cylinder by the rotation of the roller to divide the compression chamber into a plurality of spaces (333a, 333b, 333c), wherein the vane (351, 352, 353) comprises: a body portion that has a sealing surface contacting the inner circumference of the cylinder and is inserted into the roller; and a guide portion that extends from an axial end of the body portion in a direction crossing the direction the vane (351, 352, 353) slides out, and that is slidably inserted into a guide groove (311a, 321a) formed on at least one of the first and second bearings (310, 320) to restrain the vane (351, 352, 353) from sliding out of the roller toward the inner circumference of the cylinder in at least some part of the circumference of the cylinder, wherein the roller is eccentric to the inner circumference of the cylinder, characterised in that if a point at which the cylinder and the roller are closest is referred to as a contact point, the entire range of a single rotation of the roller with respect to the contact point comprises a non-contact region in which the inner circumference of the cylinder and a sealing surface of a vane (351, 352, 353) are separated from each other, the non-contact region comprises a region where the linear velocity between the cylinder and the roller is the lowest, and the entire range comprises a contact region in which the inner circumference of the cylinder and a sealing surface of a vane (351, 352, 353) are in contact with each other, the contact region comprising a region in which the linear velocity between the cylinder and the roller is the highest. a cylinder whose inner circumference is elliptical and forms a compression chamber; a first bearing and a second bearing provided on both sides of the cylinder and forming a compression chamber together with the cylinder; a roller that is attached to a rotating shaft supported by the first and second bearings (310, 320), is eccentric to the inner circumference of the cylinder, and varies the volume of the compression chamber while rotating; and a vane (351, 352, 353) that is inserted into the roller, rotates with the roller, and is pushed out toward the inner circumference of the cylinder by the rotation of the roller to divide the compression chamber into a plurality of spaces (333a, 333b, 333c), wherein the vane (351, 352, 353) comprises: a body portion that has a sealing surface contacting the inner circumference of the cylinder and is inserted into the roller; and a guide portion that extends from an axial end of the body portion in a direction crossing the direction the vane (351, 352, 353) slides out, and that is slidably inserted into a guide groove (311a, 321a) formed on at least one of the first and second bearings (310, 320) to restrain the vane (351, 352, 353) from sliding out of the roller toward the inner circumference of the cylinder in at least some part of the circumference of the cylinder, a body portion that has a sealing surface contacting the inner circumference of the cylinder and is inserted into the roller; and a guide portion that extends from an axial end of the body portion in a direction crossing the direction the vane (351, 352, 353) slides out, and that is slidably inserted into a guide groove (311a, 321a) formed on at least one of the first and second bearings (310, 320) to restrain the vane (351, 352, 353) from sliding out of the roller toward the inner circumference of the cylinder in at least some part of the circumference of the cylinder, wherein the roller is eccentric to the inner circumference of the cylinder, characterised in that if a point at which the cylinder and the roller are closest is referred to as a contact point, the entire range of a single rotation of the roller with respect to the contact point comprises a non-contact region in which the inner circumference of the cylinder and a sealing surface of a vane (351, 352, 353) are separated from each other, the non-contact region comprises a region where the linear velocity between the cylinder and the roller is the lowest, and the entire range comprises a contact region in which the inner circumference of the cylinder and a sealing surface of a vane (351, 352, 353) are in contact with each other, the contact region comprising a region in which the linear velocity between the cylinder and the roller is the highest.