# US 11,994,137 B2 · Vacuum pump

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 11,994,137 B2
- Document ID: US11994137B2
- Status: Granted
- Kind: B2
- Application number: 17/762,992
- Filed: 2020-09-18
- Published: 2022-12-29
- Granted: 2024-05-28
- Earliest claimed: 2019-09-30
- Assignees: Edwards Japan Limited
- Applicants: Edwards Japan Limited
- Inventors: Tooru Miwata; Yoshiyuki Takai
- Web page: https://patentgrep.com/patent/US11994137B2

## CPC

- F04D 19/042: {Turbomolecular vacuum pumps}
- F04D 29/083: {especially adapted for elastic fluid pumps}
- F04D 19/04: specially adapted to the production of a high vacuum, e.g. molecular pumps
- F04D 19/044: {Holweck-type pumps}
- F04D 29/053: Shafts
- F04D 29/102: {especially adapted for elastic fluid pumps}
- F04D 29/584: {cooling or heating the machine (F04D29/5846, F04D29/5853 take precedence)}
- F05D 2260/607: Preventing clogging or obstruction of flow paths by dirt, dust, or foreign particles
- F04D: NON-POSITIVE-DISPLACEMENT PUMPS (engine fuel-injection pumps F02M; ion pumps H01J41/12; electrodynamic pumps H02K44/02)
- F05D: INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS

## Abstract

A vacuum pump which suppresses occurrence of deposition caused by an exhaust gas is obtained. The vacuum pump includes: a pump portion including a shaft portion, a rotor disposed on an outer peripheral side of the shaft portion, and a stator disposed on the outer peripheral side of the rotor; a channel of the exhaust gas from the pump portion to an outlet port; and a shielding portion which suppresses contact of the exhaust gas with the shaft portion in the channel. Further, an end portion of the shielding portion has a surface opposed to the rotor.

## Claims

### Claim 1

A vacuum pump, comprising:
a pump portion including a base, a stationary shaft portion extending from the base, a rotor disposed on an outer peripheral side of the stationary shaft portion, and a stator disposed on the outer peripheral side of the rotor;
a channel of an exhaust gas from the pump portion to an outlet port; and
a shielding portion which suppresses contact of the exhaust gas with the stationary shaft portion in the channel, wherein
an end portion of the shielding portion has a surface opposed to a surface of the rotor, wherein the surface of the rotor extends radially inward from the outer peripheral side of the rotor; and
wherein the base and the stationary shaft portion are thermally insulated from the stator and the shielding portion by an insulating material having first and second contact surfaces between the stator and the base.

### Claim 2 (depends on 1)

The vacuum pump according to claim 1, wherein
the shielding portion includes an intermediate portion which extends to the end portion along a wall surface of the stationary shaft portion, and
a thickness of the intermediate portion is smaller than a thickness of the end portion.

### Claim 3 (depends on 1)

The vacuum pump according to claim 1, wherein
a distance from a wall surface of the stationary shaft portion to an outer peripheral surface of the end portion of the shielding portion is equal to or smaller than a distance from the wall surface of the stationary shaft portion to the outer peripheral surface of the rotor.

### Claim 4 (depends on 1)

The vacuum pump according to claim 1, further comprising a groove structure which suppresses inflow of the exhaust gas to the stationary shaft portion side through a clearance between the shielding portion and the rotor on at least one of a surface of the shielding portion and a surface of the rotor opposed to the surface.

### Claim 5 (depends on 1)

The vacuum pump according to claim 1, further comprising a heating member including a heater, wherein
the stationary shaft portion is cooled, and
the shielding portion is one member fixed to the heating member or a part of the heating member.