Inventor

Kotaro Naya

Inventor

Shimizu, JP

Overview

6→

Patents

1987–1994

Patent span

Mechanical engineering

Primary field (CPC F)

Patents· 6 as inventor

Public. Assignee & technology derived from the patent record. Each patent links to its LexDana page.

F04Cprimary

F04CRotary-piston, or oscillating-piston, positive-displacement machines for liquids30%

Y10STechnical subjects covered by former uspc cross-reference art collections [xracs] and digests15%

B29CShaping or joining of plastics10%

F01CRotary-piston or oscillating-piston machines or engines10%

F04DNon-positive-displacement pumps10%

F05CIndexing scheme relating to materials, material properties or material characteristics for machines, engines or pumps other than non-positive-displacement machines or engines10%

Y10TTechnical subjects covered by former us classification10%

F16JPistons5%

PatentTitleYear

5,314,321'Screw-type rotary fluid machine including rotors having treated surfaces'1994 5,223,052'Method of treating surfaces of rotors of the screw type rotary machine'1993 4,993,930'Vacuum pump apparatus and shaft sealing device therefor'1991 4,797,068'Vacuum evacuation system'1989 4,770,609'Two-stage vacuum pump apparatus and method of operating the same'1988 4,714,418'Screw type vacuum pump'1987

Career & activity timeline

Assembled from patent assignee/location history and declaration credentials.

1987–1994Patents assigned to HITACHI LTD (6)· patent assignee history

1987–1989Based in Ebina, JP· patent location history

1991–1994Based in Shimizu, JP· patent location history

Inventor activity

Assignee and location history derived from the patent record.

Assignees

Assignee	Patents	Span
HITACHI LTD	6	1987–1994

Locations

Location	Patents	Span
Shimizu, JP	3	1991–1994
Ebina, JP	3	1987–1989