DH

Donald L. Heffner

General Motors: 7 patents #2,246 of 18,328Top 15%
📍 Miamisburg, OH: #29 of 219 inventorsTop 15%
🗺 Ohio: #11,686 of 73,341 inventorsTop 20%
Overall (All Time): #768,942 of 4,157,543Top 20%
7
Patents All Time

Issued Patents All Time

Showing 1–7 of 7 patents

Patent #TitleCo-InventorsDate
4856554 Vacuum check valve and method of control Dennis G. Merical, David A. Homan 1989-08-15
4763689 Vacuum check valve Donald L. Parker 1988-08-16
4756333 Vacuum check valve Dennis G. Merical 1988-07-12
4750517 Vacuum check valve Donald L. Parker 1988-06-14
4750516 Vacuum check valve Donald L. Parker 1988-06-14
4724867 Vacuum check valve William H. Gillespie, III, David A. Homan, Dennis G. Merical, James W. Miller, Donald L. Parker 1988-02-16
4628959 Vacuum check valve Donald L. Parker 1986-12-16