Vacuum pump

摘要

The invention relates to a vacuum pump, in particular a screw pump, having preferably two displacement body shafts (2, 3), coupled via a gearing, which drive displacement bodies (12, 13), and having an inner recess (14), extending in the direction of a geometric axis (A) of the displacement body shaft (2, 3), in which a tubular body (20) extends for conducting cooling fluid while leaving a free space between an inner surface of the recess (14) and an outer surface of the body (20). To provide a vacuum pump which has a configuration having a simple construction and which is effective with regard to cooling power, it is proposed that the body (20) is in addition secured in a separate cover part (15) mounted on the suction-side end of the displacement body (12, 13), and that the free space is formed, at least in part, directly between the body (20) and the inner surface of the displacement body (12, 13) and extends continuously from the cover part (15) to a securing region of the body (20) in the displacement body shaft (2, 3), in a region of the displacement body shaft (2, 3) associated with the motor/gearing housing (4) of the displacement body shaft (2, 3).

主权项

1. A vacuum screw pump comprising,
two displacement body shafts (2,3); a gearing (12, 13), which couples the two displacement body shafts; each displacement body shaft (2, 3) having a working chamber end and a displacement body end and being cooled on the inside; a housing (4, 6) which is divided into a motor/gearing chamber (7) including a motor as well as a gearing, and a working chamber (5); a displacement body (12, 13) having an inner recess (14), extending in the direction of a geometric axis (A) of the displacement body shaft (2, 3); a tubular body (20) including an outer surface, the tubular body extends within the inner recess for conducting cooling fluid while defining a free space between an inner surface of the recess (14) and the outer surface of the tubular body; the cooling fluid able to enter the free space from the tubular body (20), and the tubular body (20) being secured in the displacement body shaft (2, 3), a separate cover part (15); a bearing (16); in addition the tubular body (20) being secured in the separate cover part (15) mounted on a suction-side end of the displacement body (12, 13), and by said separate cover part the displacement bodies are mounted the bearing (16) in the housing (4); the free space being formed, at least over a length, starting from the cover part (15) of one half up to ⅘ of the overall length (L) of the displacement body (12, 13), and said free space is directly between the outer surface of the tubular body (20) and the inner surface of the recess (14) and the free space extending continuously from the cover part (15) to a securing region of the tubular body (20) in the displacement body shaft (2, 3), and wherein the securing region of the tubular body (20) is except for the separate cover part (15) only provided in the motor/gearing chamber (7) of the housing (4, 6).