Vacuum pump

Patent metadata

Field	Value
Publication number	US-2016273552-A1
Application number	US-201514974230-A
Country	US
Kind code	A1
Filing date	Dec 18, 2015
Priority date	Mar 18, 2015
Publication date	Sep 22, 2016
Grant date	—

Abstract

A vacuum pump comprises: a stator; a rotor that rotates with respect to the stator; a pump casing in which the stator and the rotor are contained, and a suction port and a through-hole for exhaust are provided; a first exhaust duct fixed to an outer circumference of the pump casing so as to communicate with the through-hole for exhaust; and a second exhaust duct that is inserted into at least the through-hole for exhaust with a gap interposed, an exhaust gas passing inside the second exhaust duct.

First claim

What is claimed is:

1 . A vacuum pump comprising:
a stator; a rotor that rotates with respect to the stator; a pump casing in which the stator and the rotor are contained, and a suction port and a through-hole for exhaust are provided; a first exhaust duct fixed to an outer circumference of the pump casing so as to communicate with the through-hole for exhaust; and a second exhaust duct that is inserted into at least the through-hole for exhaust with a gap interposed, an exhaust gas passing inside the second exhaust duct.

2 . The vacuum pump according to claim 1 , wherein
the stator is fixed to the pump casing so as to be opposed to the rotor, and a screw groove is formed in a opposed surface of any one of the rotor and the stator, and the second exhaust duct is in thermal contact with the stator.

3 . The vacuum pump according to claim 2 , wherein the stator is formed of aluminum-based metal, and the second exhaust duct is formed of aluminum-based metal.

4 . The vacuum pump according to claim 2 , wherein the stator is formed of stainless steel, and the second exhaust duct is formed of aluminum-based metal.

5 . The vacuum pump according to claim 2 , wherein the stator is fixed to the pump casing with a heat insulating member interposed.

6 . The vacuum pump according to claim 2 , wherein a fixed wall formed at the one end of the second exhaust duct is fastened to an outer circumferential surface of the stator with bolt.

7 . The vacuum pump according to claim 2 , wherein the second exhaust duct is contacted to a lower end of the stator.

8 . The vacuum pump according to claim 7 , wherein in the temperature of the stator, the temperature of the lower end of the stator is the highest.

9 . The vacuum pump according to claim 2 further comprising a heater to heat the pump casing.

10 . The vacuum pump according to claim 1 , wherein the second exhaust duct is inserted into only the through-hole for exhaust, and;
the first exhaust duct is exchangeable.

11 . The vacuum pump according to claim 1 , wherein
the second exhaust duct is inserted into the through-hole for exhaust and the first exhaust duct with a gap interposed.

12 . The vacuum pump according to claim 11 , wherein
a gas outflow port of the second exhaust duct is disposed on an inner side in a radial direction with respect to a gas outflow port of the first exhaust duct.

13 . The vacuum pump according to claim 1 , wherein the second exhaust duct extends from a gas outflow port of the through-hole for exhaust to a gas inflow port or to an inside of the pump casing.

14 . The vacuum pump according to claim 1 , wherein
the second exhaust duct is in thermal contact with the pump casing.

15 . The vacuum pump according to claim 14 , wherein the second exhaust duct is fixed to an inner wall of the through-hole for exhaust.

16 . The vacuum pump according to claim 1 , wherein the second exhaust duct is exchangeable.

Assignees

• Shimadzu Corp

Inventors

• Tsubokawa Tetsuya

Classifications

• F04D17/10

  for compressing or evacuating · CPC title

• F04D29/28

  for centrifugal or helico-centrifugal pumps {for radial-flow or helico-centrifugal pumps} · CPC title

• F04D29/5853

  heat insulation or conduction · CPC title

• F04D29/4213

  suction ports · CPC title

• F04D29/444

  Bladed diffusers · CPC title