Dwight B Stephenson
Land Surveyors in Prior Lake, MN

5161577, Nov 10, 1992

Nov 15, 1991

7/793061

Dwight B. Stephenson - Savage MN

Eaton Corporation - Cleveland OH

F15B 908

13762524

A fluid controller (11) is provided of the type which controls the flow of fluid from a source to at least a first fluid pressure operated device. The controller is of the type including a primary, spool valve (39;39') and a follow-up sleeve valve (41;41'). The spool and sleeve are of the type in which relative rotation therebetween defines a main fluid path through a fluid meter (23), and in which axial movement of the sleeve (39') defines a parallel fluid path (FIG. 7) or an auxiliary fluid path. A neutral centering spring arrangement is provided including at least one compression spring (101) having its ends disposed in engagement with seat members (97,99) to bias the spool and sleeve toward their neutral rotary position. The compression springs (101) are disposed in annular grooves (93,95) defined by the sleeve and spool, respectively, with one of the grooves being configured to permit relative axial movement between the spool and sleeve, as the sleeve is displaced away from its neutral axial position (FIG. 6), or away from its first axial position (FIG. 9).

4804016, Feb 14, 1989

Jun 9, 1988

7/204333

William J. Novacek - Bloomington MN
Dwight B. Stephenson - Savage MN

Eaton Corporation - Cleveland OH

B62D 508, F16K 3900

13762523

A fluid controller (15) is provided of the type for directing pressurized fluid from a source (13) to a steering cylinder (17). The controller includes a housing defining right and left turn ports (32 and 34) and corresponding annular grooves (32g and 34g). The controller valving includes a cylindrical sleeve (37) and a spool (35). Steering against the cylinder stops results in trapped pressurized fluid in one of the annular grooves (32g or 34g) after the valving returns to the neutral position. The sleeve (37) is provided with pressure balancing passages (93 and 97) which are positioned to communicate trapped pressurized fluid into pressure balancing areas (85 or 99, respectively). The pressurized fluid in the balancing areas is able to counteract the clamping force on the sleeve resulting from the trapped fluid in one of the annular grooves (32g or 34g), and thereby prevent a subsequent stiction condition when the vehicle operator attempts to begin the next steering maneuver.

5329969, Jul 19, 1994

Jul 29, 1993

8/100012

Kenneth G. Rasmussen - Maple Grove MN
Dwight B. Stephenson - Savage MN
William J. Novacek - Bloomington MN

Eaton Corporation - Cleveland OH

F15B 909

13762524

A controller (11) and a system for controlling the flow of fluid to a fluid pressure operated device (C) are disclosed. The controller is of the type including a rotatable spool valve (35) and a relatively rotatable sleeve valve (37). Relative rotation between the spool and sleeve define a main fluid path (MFP) and relative axial movement therebetween defines an auxiliary fluid path (AFP). An actuator (65) generates a mechanical output (71) in response to an electrical input signal (CS) to move the sleeve (37) between its neutral axial position (FIG. 6) and an axial operating position (FIG. 7). Axial movement of the sleeve is controlled by a joystick (J). The system includes various sensors (S,PS,G,P), which can sense a predetermined condition and generate an interrupt signal to interrupt or change the gain of the electrical input signal (CS).

5115640, May 26, 1992

May 20, 1991

7/703318

Dwight B. Stephenson - Savage MN
James J. Hastreiter - Eden Prairie MN

Eaton Corporation - Cleveland OH

F15B 909

60384

An improved fluid controller (15) is provided having both rotary valving (47) actuated by the steering wheel (17), and axial valving (49) controlled by an electro-hydraulic valve (113) in response to a correction signal (31). In one embodiment, both the rotary valving and the axial valving are achieved by a primary valve member (63) and a follow-up valve member (65), and both the rotary and axial valving can be actuated simultaneously. Also disclosed is a logic control system for closed-loop control of the electro-hydraulic valve, whereby performance problems such as self-steering wander, drift, and others are substantially eliminated.

5303636, Apr 19, 1994

Mar 13, 1992

7/850712

Dwight B. Stephenson - Savage MN
James J. Hastreiter - Eden Prairie MN

Eaton Corporation - Cleveland OH

F15B 909

91471

An improved fluid controller (15) is provided having both rotary valving (47) actuated by the steering wheel (17), and axial valving (49) controlled by an electro-hydraulic valve (113) in response to a correction signal (31). In one embodiment, both the rotary valving and the axial valving are achieved by a primary valve member (63) and a follow-up valve member (65), and both the rotary and axial valving can be actuated simultaneously. Also disclosed is a logic control system for closed-loop control of the electro-hydraulic valve, whereby performance problems such as self-steering, wander, drift, and others are substantially eliminated.

4958493, Sep 25, 1990

Mar 20, 1989

7/325721

Herman P. Schutten - Bayside WI
Dwight B. Stephenson - Savage MN
Donald M. Haarstad - Chaska MN

Eaton Corporation - Cleveland OH

F16D 3102

60384

An open-center fluid controller (15) is disclosed for controlling the flow of fluid to a steering cylinder (25). The controller includes a fluid meter (29) and valving arrangement (27), including a valve spool (43) and a sleeve (45), which define a main fluid path. The main path includes a fixed flow control orifice (86), a variable flow control orifice (87), the fluid meter (29), and a variable flow control orifice (89). In accordance with the invention, the spool and sleeve define an amplification fluid path (101), including a variable amplification orifice (99), in parallel with the main fluid path, and disposed to amplify the flow of fluid through the meter (29). In order to facilitate manual steering, the amplification orifice (99) reaches its maximum flow area when the spool and sleeve are in a normal operating position (FIG. 6). The amplification orifice then decreases and closes as the displacement between the spool and sleeve reach a maximum displacement (FIG. 7). As a result, the amplification fluid path (101) is closed at maximum valve displacement, thus making it possible to manually steer the vehicle.

4967362, Oct 30, 1990

Jan 30, 1989

7/302889

Herman P. Schutten - Bayside WI
Dwight B. Stephenson - Savage MN
Oliver W. Johnson - Chaska MN

Eaton Corporation - Cleveland OH

G06F 1550, A01D 3400

36442407

Apparatus for automatically steering a farm crop vehicle into rows of corn by sensing the locations of the rows ahead of the vehicle on both sides of the vehicle. The apparatus senses the plants of each row by means of contact sensors that touch the plants as the crop vehicle approaches them. The data thus obtained are processed by an on-board microcontroller to determine the lateral location of the crop vehicle relative to the rows. Also, the frequencies of encountering plants in laterally spaced-apart rows provided information regarding turning of the vehicle, i. e. , incipient changes of lateral position. This is used to produce a further feedback signal that improves the automatic steering, especially where the rows are curved. Having the turning-feedback signal in the servo loop also permits higher loop gain without instability, which reduces tracking error even further. The microcontroller provides steering commands that automatically maintain the crop vehicle on a proper course for stripping the corn, cutting the crop, etc.

5080135, Jan 14, 1992

Oct 24, 1990

7/602829

Dwight B. Stephenson - Savage MN

Eaton Corporation - Cleveland OH

F15B 1304, F15B 1310

13762524

A fluid controller (11) is disclosed for controlling the flow of fluid from a source (73) to a steering cylinder (77), especially for use on large, articulated vehicles. The controller includes a fluid meter (17) and a valving arrangement including a spool (33) and a sleeve (37). The housing and the valving define a main fluid path (113) including a main variable flow control orifice (A1), and the fluid meter (17) in series flow relation between an inlet port (23) and the first control fluid port (27). In accordance with the invention, the main variable flow control orifice is formed by a first fluid passage (93R; 123L) defined by the spool, being in fluid communication with a first fluid port means (101R; 131R) defined by the sleeve. The first fluid port means extends circumferentially to provide continuous fluid communication between the inlet port and the first fluid passage of the spool, as the spool rotates relative to the sleeve from the neutral position to the first operating position. The relative rotation of the spool and sleeve extends at least about 45 degrees, and in the subject embodiment, extends about 60 degrees.

RE34746, Oct 4, 1994

Jan 17, 1992

7/822245

Herman P. Schutten - Bayside WI
Dwight B. Stephenson - Savage MN
Donald M. Haarstad - Chaska MN

Eaton Corporation - Cleveland OH

F16D 3102

60384

An open-center fluid controller (15) is disclosed for controlling the flow of fluid to a steering cylinder (25). The controller includes a fluid meter (29) and valving arrangement (27), including a valve spool (43) and a sleeve (45), which define a main fluid path. The main path includes a fixed flow control orifice (86), a variable flow control orifice (87), the fluid meter (29), and a variable flow control orifice (89). In accordance with the invention, the spool and sleeve define an amplification fluid path (101), including a variable amplification orifice (99), in parallel with the main fluid path, and disposed to amplify the flow of fluid through the meter (29). In order to facilitate manual steering, the amplification orifice (99) reaches its maximum flow area when the spool and sleeve are in a normal operating position (FIG. 6). The amplification orifice then decreases and closes as the displacement between the spool and sleeve reach a maximum displacement (FIG. 7). As a result, the amplification fluid path (101) is closed at maximum valve displacement, thus making it possible to manually steer the vehicle.

5404722, Apr 11, 1995

Jan 14, 1994

8/181689

Makoto Nagao - Kameoka, JP
Dwight B. Stephenson - Savage MN

Eaton Corporation - Cleveland OH

F16D 3102, F15B 910

60384

A torque generator steering device (10) is disclosed of the type including a gerotor displacement mechanism (19) and valving (9), by the rotation of an input shaft (1) results in a hydrostatic power assist to an output shaft (2). In parallel with the power assist path, the input shaft (1) is connected by a torsion bar (15) to a connecting shaft (3) which, in turn, is connected to the output shaft (2). The connections between the torsion bar (15) and the connecting shaft (3), and between the connecting shaft (3) and the output shaft (2) are substantially zero backlash mechanical connections, thus providing a main torque transmitting path in parallel with the power assist path. Below a predetermined level of input torque, rotation of the input shaft (1) results in an immediate and corresponding rotation of the output shaft (2), thus providing a manual steering mode.