David R Schaefer

US Patent:

6336560, Jan 8, 2002

Filed:

Feb 1, 2000

Appl. No.:

09/495728

Inventors:

David J. Schaefer - Yankton SD

Assignee:

Astec Industries, Inc. - Chattanooga TN

International Classification:

B07C 512

US Classification:

209676, 209395, 209408

Abstract:

A grizzly screen apparatus has a screen of grizzly bars having first ends mounted in a transverse end member and second ends placed in a slotted comb member having alternating shallow and deep bed slots. The screen is rotatable about a transverse axis whereby the second ends of secondary grizzly bars in the deep bed slots are lowered relative to the second ends of grizzly bars in the shallow bed slots, resulting in simultaneous steepening of the screen and an increase of the interbar distance, to remove obstructing oversize objects from the screen. Each grizzly bar has a transverse lock bar at the first end which retains the grizzly bar within an aperture in the transverse end member without bolts or other fasteners. Obstructions on the grizzly screen may be cleared without the use of manually operated tools, and if desired, may be cleared by remote control.

US Patent:

7823515, Nov 2, 2010

Filed:

Jul 22, 2009

Appl. No.:

12/507210

Inventors:

David J. Schaefer - Yankton SD, US
Nathan P. Dimmer - Yankton SD, US
Steven J. Knight - Mission Hill SD, US
Jerry R. Dimmer - Yankton SD, US
Michael P. Krajewski - Yankton SD, US
Kevin J. Kleinsasser - Yankton SD, US
Carla K. Ewald - Yankton SD, US

Assignee:

Shur Company - Yankton SD

International Classification:

B61D 39/00
B60P 7/02

US Classification:

10537702, 10537706, 29610001

Abstract:

A rail car cover system including a rail car, a first cover section and a second cover section. The rail car has an opening. The first cover section is operably attached to the rail car. The first cover section includes a first hinge mechanism and a first cover material. The second cover section is operably attached to the rail car. The second cover section includes a second hinge mechanism and a second cover material. The first cover section and the second cover section are both movable between a closed configuration and an open configuration. When in the closed configuration, the first cover section and the second cover section substantially cover the opening.

US Patent:

7841642, Nov 30, 2010

Filed:

Dec 29, 2008

Appl. No.:

12/345000

Inventors:

David Joseph Schaefer - Yankton SD, US

Assignee:

Shur Company - Yankton SD

International Classification:

B60P 7/04

US Classification:

296 98, 29610012

Abstract:

A retractable tarping system including an end support surface, a shaft, a tarp, a spool, an end plate assembly, and a cable. The tarp and the spool are operably attached to the shaft. The end plate assembly is attached to the shaft for movement with respect to the first end support surface. The cable is attached to the end support surface and extends at least one time around the first spool.

US Patent:

7967363, Jun 28, 2011

Filed:

Sep 8, 2010

Appl. No.:

12/877712

Inventors:

David J. Schaefer - Yankton SD, US
Nathan P. Dimmer - Yankton SD, US
Steven J. Knight - Mission Hill SD, US
Jerry R. Dimmer - Yankton SD, US
Michael P. Krajewski - Yankton SD, US
Kevin J. Kleinsasser - Yankton SD, US
Carla K. Ewald - Yankton SD, US

Assignee:

Shorma Company - Springfield SD

International Classification:

B60P 7/02

US Classification:

29610006

Abstract:

A rail car cover system including a rail car, a first cover section and a second cover section. The rail car has an opening. The first cover section is operably attached to the rail car. The first cover section includes a first corner hinge assembly, a first intermediate hinge assembly and a first cover material. The first corner hinge assembly is attached to the first cover material. The first intermediate hinge assembly is slidable with respect to the first cover material. The second cover section is operably attached to the rail car. The second cover section includes a second corner hinge assembly, a second intermediate hinge assembly and a second cover material. The second corner hinge assembly is attached to the second cover material. The second intermediate hinge assembly is slidable with respect to the second cover material. The first cover section and the second cover section are both movable between a closed configuration and an open configuration.

US Patent:

8141498, Mar 27, 2012

Filed:

Apr 6, 2009

Appl. No.:

12/418895

Inventors:

Derrick K. Barr - Crofton NE, US
Christopher J. McCallum - Yankton SD, US
David J. Schaefer - Yankton SD, US

International Classification:

B61D 17/00

US Classification:

105396, 105399, 105401

Abstract:

A rail car extension system including a first main rail section, a second main rail section and a plurality of bow structures. The first main rail section is mounted with respect to an upper surface of the first side wall. The first main rail section includes a first upper rail portion and a first lower rail portion that extends from the first upper rail portion. The second main rail section is mounted with respect to an upper surface of the second side wall. The second main rail section includes a second upper rail portion and a second lower rail portion that extends from the second upper rail portion. The plurality of bow structures are each attached to and extend between the first main rail section and the second main rail section.

US Patent:

42627850, Apr 21, 1981

Filed:

Jul 19, 1978

Appl. No.:

5/926082

Inventors:

Larry B. Anderson - Racine WI
Clark J. Hamkins - Racine WI
Harry A. Petrak - Boulder CO
David V. Schaefer - Burlington WI

Assignee:

The Mechanex Corporation - Englewood CO

International Classification:

F16D 1100
F16D 4320

US Classification:

192 35

Abstract:

A clutch interposed between a hub mounted for rotation on a spindle and a selectively driveable axle which extends longitudinally through the spindle serves to engage the hub to the axle when the clutch is subjected to torque caused by placement of the axle in a dynamic or driving axle mode. When the axle is in a passive or non-driving axle mode the clutch serves to disengage the hub from the axle whereby the hub is free-wheeling on the spindle.

US Patent:

60988118, Aug 8, 2000

Filed:

Jul 31, 1996

Appl. No.:

8/690478

Inventors:

David J. Schaefer - Yankton SD

Assignee:

Astec Industries, Inc. - Chattanooga TN

International Classification:

B07B 149

US Classification:

209395

Abstract:

A grizzly screen apparatus has a screen of grizzly bars having first ends mounted in a transverse end member and second ends placed in a slotted comb member having alternating shallow and deep bed slots. The screen is rotatable about a transverse axis whereby the second ends of secondary grizzly bars in the deep bed slots are lowered relative to the second ends of grizzly bars in the shallow bed slots, resulting in simultaneous steepening of the screen and an increase of the interbar distance, to remove obstructing oversize objects from the screen. Each grizzly bar has a transverse lock bar at the first end which retains the grizzly bar within an aperture in the transverse end member without bolts or other fasteners. Obstructions on the grizzly screen may be cleared without the use of manually operated tools, and if desired, may be cleared by remote control.