Bradley J Kramer

US Patent:

20040112659, Jun 17, 2004

Filed:

Dec 17, 2002

Appl. No.:

10/321325

Inventors:

Bradley Kramer - Milwaukee WI, US
Eric Griesbach - North Prairie WI, US
Jeffrey Rogala - Delafield WI, US

International Classification:

B62D033/10

US Classification:

180/089120

Abstract:

A suspension system isolates the operator cab or seat from vibrations in the chassis of a vehicle. At least one hydraulic actuator is connected between the cab or seat and the vehicle chassis. An accumulator is coupled to the hydraulic actuator and acts as a hydraulic spring to attenuate high frequency vibrations. An electrically operable, three-position, closed-center control valve selectively connects the hydraulic actuator to a source of pressurized hydraulic fluid or a reservoir. Sensors detect acceleration and displacement of the cab or seat to which a controller responds by operating the valve. That control of the valve actively drives the hydraulic actuator to produce motion that counters the relatively low frequency vibrations from the chassis.

US Patent:

20050082127, Apr 21, 2005

Filed:

Oct 20, 2003

Appl. No.:

10/689387

Inventors:

Dennis Barber - Waukesha WI, US
Bradley Kramer - Boston MA, US
Eric Griesbach - North Prairie WI, US

International Classification:

F16F009/34

US Classification:

188266200

Abstract:

A suspension system has a pair of cylinders connected between the cab or axle and a chassis of a vehicle to isolate the driver from vibrations. A pair of hydraulic cylinders is coupled to opposite sides of the cab or axle and to the vehicle chassis. A separate accumulator is coupled each hydraulic cylinder to act as a hydraulic spring that attenuates side to side motion. A leveling valve selectively control the flow of fluid to or from both hydraulic cylinders to level the cab or seat in response to load changes.

US Patent:

20170009753, Jan 12, 2017

Filed:

Jul 8, 2016

Appl. No.:

15/205517

Inventors:

- Waukesha WI, US
Bradley Kramer - Oconomowoc WI, US
Dwight Stephenson - Oconomowoc WI, US
Eric Hamkins - Waukesha WI, US

Assignee:

HUSCO International, Inc. - Waukesha WI

International Classification:

F04B 1/053
F15B 11/16
F04B 53/16
F15B 11/08
F04B 1/04
F04B 49/22

Abstract:

A system and method for machinery performing work with hydraulic actuators. Radial hydraulic pumps are aligned end-to-end along a common driveshaft axis to form a multi-pump assembly having a plurality of piston/cylinder units extending in a radial direction. Two or more piston/cylinder units are associated with one another to form multiple piston/cylinder groups. A plurality of control valves combines individual output flows from the two or more associated piston/cylinder units into respective common output flows for each respective piston/cylinder group. A plurality of flow control devices varies the common output flow from each respective piston/cylinder group by throttling inlet flow to the two or more associated piston/cylinder units in each respective piston/cylinder group. Each respective common output flow is directed from each respective piston/cylinder group to a hydraulic actuator on the heavy machinery to control its direction of movement.

US Patent:

20140199187, Jul 17, 2014

Filed:

Jan 15, 2013

Appl. No.:

13/741928

Inventors:

- Waukesha WI, US
Bradley Kramer - Oconomowoc WI, US
Joe Pfaff - Wauwatosa WI, US

Assignee:

HUSCO International, Inc. - Waukesha WI

International Classification:

F04B 1/053

US Classification:

417273

Abstract:

A pump system has a piston pump. The piston pump has a cylinder block with an inlet port, an outlet port, and a plurality of cylinders. Each cylinder in the plurality of cylinders is connected to the inlet port by an inlet passage and to the outlet port by an outlet passage. The piston pump has a plurality of pistons disposed in the plurality of cylinders. A drive shaft drives the pistons within the cylinders. A throttle member independently throttles flow in each inlet passage. The pump system has an electrohydraulic actuator governing movement of the throttle member.