Baler density control system

• US 5,819,643 A
• Filed: 12/18/1997
• Issued: 10/13/1998
• Est. Priority Date: 12/18/1997
• Status: Expired due to Term

• Current Assignee: Biothera, Inc.
• Original Assignee: New Holland North America Incorporated (CNH Industrial N.V.)
• Inventors: Ellis, Preston L., McIlwain, Irwin D.
• Primary Examiner(s): GERRITY, STEPHEN FRANCIS
• Application Number:
  US08/993,111
• Time in Patent Office: 299 Days
• Field of Search: 100/41, 100/43, 100/179, 100/191, 100/192
• US Class Current: 100/43
• CPC Class Codes: A01F 15/0825 Regulating or controlling density or shape of the bale
• CPC Class Codes: B30B 9/3007 Control arrangements
• CPC Class Codes: B30B 9/3025 Extrusion chambers with adjustable outlet opening

Abstract

An agricultural baler for picking up crop material and forming it into a rectangular shaped package, having a bale density control system. The baler has a bale case including four wall members forming a generally rectangular opening, at least one of which wall members includes a tension rail movably mounted to vary the cross sectional area of the rectangular opening. The baler also has a hydraulic control arrangement including a hydraulic cylinder operable for changing the position of the tension rail, a pressure control valve comprising a variable relief valve, and a hydraulic circuit for coupling the hydraulic cylinder to the pressure control valve. The relief valve is selectively controlled by an electronic controller.

Claims

1. In a baler having

a bale case including four wall members forming a generally rectangular opening, at least one of which wall members includes a tension rail movably mounted to vary the cross sectional area of said rectangular opening, and

hydraulic control means including a hydraulic cylinder operable for changing the position of said tension rail, a pressure control valve, and a hydraulic circuit for coupling said hydraulic cylinder to said pressure control valve, the improvement comprising

said pressure control valve comprises a variable relief valve, and

means for electronically controlling said variable relief valve.

2. In a baler as set forth in claim 1 wherein

said variable relief valve includes a solenoid having a coil, and

said means for electronically controlling includes a circuit having output terminals connected to said solenoid for providing a selectively variable signal to said coil of said solenoid for varying the pressure in said hydraulic circuit by varying said selectively variable signal.

3. In a baler as set forth in claim 2 wherein

said circuit includes an amplifier having a variable output for varying the level of current through said coil.

4. In a baler as set forth in claim 3 wherein

said circuit includes a voltage source, and

a potentiometer having input and output terminals, said output terminals connected to said amplifier, and said voltage source connected across said input terminals whereby said potentiometer provides a variable input voltage to said amplifier for varying said variable output.

5. In a baler as set forth in claim 4 wherein

said amplifier comprises a pulse width modulation type amplifier.

6. A bale density control system comprising in combination

a baler having a bale case including four wall members forming a generally rectangular opening, at least one of which wall members includes a tension rail movably mounted to vary the cross sectional area of said rectangular opening,

hydraulic control means including a hydraulic cylinder operable for changing the position of said tension rail, a pressure control valve comprising a variable relief valve, and a hydraulic circuit for coupling said hydraulic cylinder to said pressure control valve, and

means for electronically controlling said variable relief valve.

7. In a bale density control system as set forth in claim 6 wherein

said variable relief valve includes a solenoid having a coil, and

said means for electronically controlling includes a circuit having output terminals connected to said solenoid for providing a selectively variable signal to said coil of said solenoid for varying the pressure in said hydraulic circuit by varying said selectively variable signal.

8. In a bale density control system as set forth in claim 7 wherein

said circuit includes an amplifier having a variable output for varying the level of current through said coil.

9. In a bale density control system as set forth in claim 8 wherein

said circuit includes a voltage source, and

a potentiometer having input and output terminals, said output terminals connected to said amplifier, and said voltage source connected across said input terminals whereby said potentiometer provides a variable input voltage to said amplifier for varying said variable output.

10. In a bale density control system as set forth in claim 9 wherein

said amplifier comprises a pulse width modulation type amplifier.

11. In a bale density control system as set forth in claim 6 wherein

said at least one wall member comprises first and second wall members each including a tension rail movably mounted to vary said cross sectional area.

12. In a bale density control system as set forth in claim 6 wherein

said hydraulic control means includes a second hydraulic cylinder operable in concert with said hydraulic cylinder for changing the position of said tension rail.

13. In a bale density control system as set forth in claim 6 wherein

said four one wall members each include at least one tension rail movably mounted to vary said cross sectional area.

14. In a baler having

a bale case including four wall members forming a generally rectangular opening, at least one of which wall members includes a tension rail movably mounted to vary the cross sectional area of said rectangular opening, and

hydraulic control means including a hydraulic cylinder operable for changing the position of said tension rail, a pressure control valve, and a hydraulic circuit for coupling said hydraulic cylinder to said pressure control valve, the improvement comprising

said pressure control valve comprises a variable relief valve including a solenoid having a coil, and

means for electrically controlling said variable relief valve,

said means for electrically controlling includes a circuit having output terminals connected to said solenoid for providing a selectively variable signal to said coil of said solenoid for varying the pressure in said hydraulic circuit by varying said selectively variable signal.