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Inventor

Donald D. Gronholz

Inventor
Bloomington, MN, US

Overview

5→
Patents
1977–1989
Patent span
Performing operations
Primary field (CPC B)

Patents· 5 as inventor

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

Y10Tprimary
Y10TTechnical subjects covered by former us classification23%
B01DSeparation15%
B23CMilling15%
B23QDetails, components, or accessories for machine tools, e.g. arrangements for copying or controlling15%
B27DWorking veneer or plywood15%
B27CPlaning, drilling, milling, turning or universal machines for wood or similar material8%
G11BInformation storage based on relative movement between record carrier and transducer8%
PatentTitleYear
RE033045'Router guide unit'19894,657,570'Air filter device'19874,617,122'Crimp seal pleated filter assembly'19864,512,891'Pleated filter element with controlled expansibility and frame therefor'19854,044,805'Router guide unit'1977

Career & activity timeline

Assembled from patent assignee/location history and declaration credentials.

1977Patents assigned to GRONHOLZ DONALD D (1)· patent assignee history
1977–1989Based in Bloomington, MN, US· patent location history
1985–1987Patents assigned to DONALDSON CO INC (3)· patent assignee history
1985Based in Minneapolis, MN, US· patent location history

Inventor activity

Assignee and location history derived from the patent record.

Assignees
AssigneePatentsSpan
DONALDSON CO INC31985–1987
GRONHOLZ DONALD Dself11977
Locations
LocationPatentsSpan
Bloomington, Minnesota, US41977–1989
Minneapolis, Minnesota, US11985