Cam driven low profile sickle drive

Patent metadata

Field	Value
Publication number	US-9545052-B2
Application number	US-201214128119-A
Country	US
Kind code	B2
Filing date	May 25, 2012
Priority date	May 27, 2011
Publication date	Jan 17, 2017
Grant date	Jan 17, 2017

Abstract

The drive has an input rotatable about an upstanding rotational axis and carries a cam followed by a pivot arm pivotable about an upstanding pivotal axis. A power source is connected in rotatably driving relation to the input. The pivot arm connects to a knife assembly of a sickle. The input, cam and pivot arm are generally flat, and the power source is vertically coextensive therewith for incorporation in or below the floor of a header of a plant cutting machine. Rotation of the input causes offset movement of the cam about the rotational axis, resulting in sideward pivoting of the pivot arm and sickle knife. A second cam drive can oppositely drive a second sickle knife, such that opposite forces generated by operation of the drives will be largely canceled.

First claim

What is claimed is:

1. A sickle drive for a plant cutting machine having a first sickle knife assembly supported for side to side reciprocating movement along a forward end of the machine, and a rotary power source for driving the first sickle knife assembly, the sickle drive comprising:
a rotatable first input element for being driven by the rotary power source and supported in a cavity for rotation about a generally upstanding first rotational axis,
a first cam element supported in the cavity in connection with the first input element for rotation thereby, the first cam element including a cam surface extending about the first rotational axis which varies in radial distance therefrom,
a first pivot arm having a first end and an opposite upwardly extending second end and configured for connection to the first sickle knife assembly, and
a first pivot shaft supporting the first pivot arm for sideward pivotal movement about an upstanding first pivotal axis, the first end of the first pivot arm including a cam follower configured and positioned in following relation to the first cam element such that rotation of the first cam element about the first rotational axis will move the first end radially relative to the first rotational axis to reciprocatingly pivot the first pivot arm sidewardly, and wherein the first cam element is positioned between opposing ends of the cam follower.

2. The sickle drive of claim 1 , further comprising:
a rotatable second input element supported in the cavity for rotation about a generally upstanding second rotational axis,
a second cam element supported in the cavity in connection with the second input element for rotation thereby, the second cam element including a cam surface extending about the second rotational axis which varies in radial distance therefrom,
a second pivot arm having a first end and an opposite upwardly extending second end and configured for connection to a second knife assembly of the plant cutting machine, and
a second pivot shaft supporting the second pivot arm for sideward pivotal movement about an upstanding second pivotal axis, the first end of the second pivot arm including a cam follower configured and positioned in following relation to the second cam element such that rotation of the second cam element about the second rotational axis will move the first end of the second pivot arm radially relative to the second rotational axis to reciprocatingly pivot the second pivot arm sidewardly.

3. The sickle drive of claim 2 , wherein the first and second input elements are connected so as to be rotated in opposite directions by the rotary power source.

4. The sickle drive of claim 1 , wherein the second end of the first pivot arm comprises the first pivot shaft.

5. The sickle drive of claim 4 , wherein the first input element is disk shaped and the first end of the pivot arm is disposed below a forward portion thereof and extends forwardly to the pivot shaft.

6. The sickle drive of claim 5 , wherein the power source comprises a motor.

7. The sickle drive of claim 6 , wherein the motor is a fluid motor or an electric motor.

8. The sickle drive of claim 1 , wherein the first cam element is below the rotatable first input element.

9. The sickle drive of claim 1 , wherein the first cam element extends proud from the rotatable first input element.

10. The sickle drive of claim 1 , wherein the cam follower is pivotably connected to the first pivot arm and includes:
an elongated body,
a first roller about a first end of the elongated body, and
a second roller about a second end of the elongated body opposite the first end.

11. The sickle drive of claim 10 , wherein each of the first and second rollers engages the first cam element.

12. A sickle drive comprising;
a cavity having a forward end disposed just rearwardly of a sidewardly extending sickle of a header of an agricultural plant cutting machine; and
a cam drive mechanism including:
a rotatable first input element supported at least partially in the cavity for rotation about a generally upstanding first rotational axis,
a first cam element extending proud of the first input element for rotation thereby in about the first rotational axis, the first cam element having a generally horizontal cam profile laterally offset relative to the first rotational axis,
a first pivot arm having a first end including a cam follower disposed in following relation to the first cam element, the first pivot arm extending to a second end,

a first pivot shaft supporting the first pivot arm for rotation about a generally upstanding first pivotal axis, such that the first pivot arm will pivot about the first pivotal axis by following the cam profile of the first cam element, and
a first knife arm connected to the first pivot shaft and connecting to a first knife assembly of the sickle, such that the first knife assembly will be reciprocated by the rotation of the first pivot shaft.

13. The sickle drive of claim 12 , further comprising a second cam drive mechanism including:
a rotatable second input element supported at least partially in the cavity for rotation about a generally upstanding second rotational axis,
a second cam element in connection with the second input element for rotation thereby about the second rotational axis, the second cam element having a generally horizontal cam profile laterally offset relative to the second rotational axis,
a second pivot arm having a first end including a cam follower disposed in following relation to the second cam element, the second pivot arm extending forwardly to a second end,
a second pivot shaft supporting the second pivot arm for rotation about a generally upstanding second pivotal axis, such that the second pivot arm will pivot sidewardly about the second pivotal axis by following the cam profile of the second cam element, and
a second knife arm connected to the second pivot shaft and connecting to a second knife assembly of the sickle, such that the second knife assembly will be reciprocated sidewardly relative to the enclosure or floor by the rotation of the second pivot shaft.

14. The sickle drive of claim 13 , wherein the first input element and the second input element are connected together for joint rotation in opposite rotational directions for reciprocatingly moving the first and second sickle knife assemblies sidewardly simultaneously in opposite directions, such that sideward forces generated by the movements of the knife assemblies will substantially cancel each other.

15. The sickle drive of claim 14 , further comprising a rotatable power source connected in rotatably driving relation to one of the first input element and the second input element, and substantially vertically coextensive with the sickle drive.

16. The sickle drive of claim 15 , wherein the power source comprises a fluid motor or an electric motor.

17. The sickle drive of claim 16 , wherein the first cam profile and the second cam profile have shapes that are substantially mirror images of each other.

18. A header for a plant cutting machine comprising:
a first sickle knife assembly supported for side to side reciprocating movement along a forward end of the machine;
a rotary power source for driving the first sickle knife assembly; and
a sickle drive that includes:
a rotatable first input element driven by the rotary power source and supported in a cavity below a floor of the header for rotation about a generally upstanding first rotational axis,
a first cam element extending outwardly from an outer surface of the first

Assignees

• Cook Joel T
• Bich Gary L
• Dechristopher David M
• Cnh Ind America Llc

Inventors

• Cook Joel T
• Bich Gary L
• Dechristopher David M

Classifications

• A01D34/145

  Devices for connecting the knife-bars to the driving mechanism · CPC title

• A01D34/04 Primary

  with cutters at the front · CPC title

• A01D34/30 Primary

  Driving mechanisms for the cutters · CPC title