Material reduction machine with dynamic startup control

Patent metadata

Field	Value
Publication number	US-12239996-B2
Application number	US-202218053972-A
Country	US
Kind code	B2
Filing date	Nov 9, 2022
Priority date	Nov 15, 2021
Publication date	Mar 4, 2025
Grant date	Mar 4, 2025

Abstract

A material reduction machine includes a prime mover driving a cutting mechanism. A drive system receives a signal to initiate rotation of a cutting mechanism. A sensor senses a machine load parameter and reports a signal to a controller operatively coupled to the clutch to control sequential engagement cycles from the engine to the cutting mechanism. The controller utilizes a stored first disengagement threshold value for stopping a first engagement cycle and continues monitoring the signal as the machine load parameter increases momentarily after reaching the first disengagement threshold. The controller determines and adopts a second disengagement threshold value based on observation of the machine load parameter indicative of maximum load during the continued monitoring after the first disengagement threshold is realized, and further being based on a stored correction factor. The second disengagement threshold value is used for a second engagement cycle.

First claim

What is claimed is:

1. A material reduction machine comprising:
a cutting mechanism;
a prime mover;
a drive system coupled with the cutting mechanism and prime mover configured to drive the cutting mechanism, the drive system having a clutch;
the clutch having an engaged state wherein the clutch transfers power from the prime mover to the cutting mechanism, and a disengaged state wherein power is not transferred from the prime mover to the cutting mechanism;
a sensor operable to sense a machine load parameter; and
a controller coupled to the sensor and programmed to receive a signal representing the sensed machine load parameter, the controller being operatively coupled to the clutch to control engagement and disengagement of each of a plurality of sequential engagement cycles of the clutch, wherein the controller is further programmed to:
utilize a stored first disengagement threshold value of the machine load parameter for disengaging the clutch of a first engagement cycle of the plurality of sequential engagement cycles when the sensor signals to the controller that the first disengagement threshold value is realized,
continue monitoring the sensor signal of the machine load parameter momentarily after reaching the first disengagement threshold,
determine and adopt a second disengagement threshold value, the second disengagement threshold value being based on an observation of the sensed machine load parameter indicative of maximum load during the continued monitoring after the first disengagement threshold is realized, and further being based on a stored correction factor, and
utilize the second disengagement threshold value for disengaging the clutch of a second engagement cycle of the plurality of sequential engagement cycles following the first engagement cycle when the sensor signals to the control that the second disengagement threshold value is realized.

2. The material reduction machine of claim 1 , wherein the controller is further programmed to adopt a third disengagement threshold value, the third disengagement threshold value being based on an observation of the machine load parameter indicative of maximum load during continued monitoring of the sensor signal after the second disengagement threshold is realized, and further being based on the correction factor.

3. The material reduction machine of claim 1 , wherein the controller is further programmed to calculate a difference between a target value of the machine load parameter corresponding to a maximum allowable machine load and the value of the machine load parameter indicative of the maximum load after the first disengagement threshold is realized, and calculate the second disengagement threshold value by applying the correction factor to the calculated difference so that the actual maximum machine load after the second disengagement threshold is realized is brought closer to the maximum allowable machine load than the actual maximum machine load after the first disengagement threshold is realized.

4. The material reduction machine of claim 1 , wherein the prime mover is an internal combustion engine, and the machine load parameter is operation speed of the internal combustion engine.

5. The material reduction machine of claim 1 , wherein the clutch is an electromagnetic clutch, and an equal amount of voltage is applied to the clutch during every clutch engagement of the plurality of sequential engagement cycles.

6. The material reduction machine of claim 1 , wherein the prime mover is an electric motor and the machine load parameter is torque output from the electric motor or electrical current draw by the electric motor.

7. The material reduction machine of claim 1 , wherein the controller is further programmed to identify completion of a cutting mechanism start-up process including the plurality of sequential clutch engagement cycles, and in response to identifying the completion of the cutting mechanism start-up process, re-adopt the stored first disengagement threshold value for a first engagement cycle of a subsequent cutting mechanism start-up process.

8. The material reduction machine of claim 7 , wherein the controller is further programmed to identify completion of a cutting mechanism start-up process including the plurality of sequential clutch engagement cycles in response to the clutch being engaged for a predetermined amount of elapsed time without disengagement.

9. The material reduction machine of claim 7 , wherein the controller is further programmed to identify completion of a cutting mechanism start-up process including the plurality of sequential clutch engagement cycles in response to not reaching the disengagement threshold value within a predetermined amount of time during the corresponding engagement cycle, which is the first engagement cycle, the second engagement cycle, or a subsequent engagement cycle.

10. The material reduction machine of claim 1 , wherein the controller is programmed to begin the plurality of sequential engagement cycles when the sensor signals the prime mover is rotating at a predefined idle speed.

11. The material reduction machine of claim 1 , wherein the material reduction machine is a stump cutter, and the cutting mechanism is a cutter wheel having a plurality of comminution cutters.

12. The material reduction machine of claim 1 , wherein the cutting mechanism of the material reduction machine is a drum having a plurality of comminution cutters.

13. The material reduction machine of claim 1 , wherein the controller is further programmed to abort the plurality of sequential engagement cycles and/or prevent a subsequent plurality of sequential engagement cycles upon determination that the plurality of sequential engagement cycles constitute an unsuccessful cutting mechanism start-up process in which the cutting mechanism fails to reach a predefined running state for material reduction.

14. The material reduction machine of claim 13 , wherein the controller is programmed to determine the unsuccessful cutting mechanism start-up process on the basis of a stored maximum limit value for number of clutch engagement cycles.

15. The material reduction machine of claim 13 , wherein the controller is programmed to determine the unsuccessful cutting mechanism start-up process on the basis of a cutting mechanism speed or a drive system speed.

16. A material reduction machine comprising:
a cutting mechanism;
an internal combustion engine;
a drive system configured coupled to the internal combustion engine and the cutting mechanism configured to selectively transfer power from the internal combustion engine to the cutting mechanism;
the drive system having a clutch;
the clutch having a power transfer state wherein the clutch transfers power from the prime mover to the cutting mechanism, and a disengaged state wherein power is not transferred from the prime mover to the cutting mechanism;
a sensor operable to sense a load on the material reduction machine via detection of droop in the operation speed of the internal combustion engine; and
a controller coupled to the sensor and programmed to receive a signal indicative of the sensed droop in the operation speed, the controller being operatively coupled to the clutch to control power transfer of each of a plurality of sequential power transfer cycles,
wherein the controller is programmed to:
utilize a stored first operation speed trip point for disengaging a first power transfer cycle of the plurality of sequential power transfer cycles when the sensor signals to the controller that the first operation speed trip point is realized, and to

Assignees

• Vermeer Mfg Co

Inventors

• Breja Joseph Edward
• Barker David Isaac

Classifications

• B02C13/30

  Driving mechanisms · CPC title

• A01G23/067 Primary

  by comminuting the tree stumps · CPC title

• F02D29/00

  Controlling engines, such controlling being peculiar to the devices driven thereby, the devices being other than parts or accessories essential to engine operation, e.g. controlling of engines by signals external thereto · CPC title

• F02D2200/101

  Engine speed · CPC title

• F16D27/00

  Magnetically- {or electrically-} actuated clutches; Control or electric circuits therefor (clutches with magnetisable particles F16D37/02; {with electro-rheological fluids F16D37/008}) · CPC title