The present invention relates to systems for controlling the operation of balers. More specifically, the present invention concerns a system for controlling a transfer of power from a tractor to a baler.
Large square balers are used in the agricultural industry to create large substantially rectangular bales of crop material by moving over crop windrows to collect loose crop material, compress it, and form it into bales that are then tied and ejected. To that end, a baler is typically mechanically coupled with a tractor, and a power take-off (PTO) mechanism transfers power from the tractor engine to drive the baler operation. The baler picks up the loose crop material and moves it into a baling chamber where a reciprocating plunger compresses the crop material into a growing bale. Once the bale reaches a predetermined length it is tied and ejected through the rear of the baler. The process then continues to create the next bale.
Large square balers typically have flywheels to smooth operation, and starting a large square baler requires substantial amount of torque from the PTO to overcome the resting inertia of the flywheel and other components. High density large square balers require relatively large flywheels, and the higher inertia results in higher starting torques than some tractor PTO clutches can reliably provide for baler startup, and can shorten clutch longevity. The required torque is further increased during restarting if the reciprocating plunger is initially positioned against a bale in the baling chamber, and the additional load of the bale as the reciprocating plunger attempts to push past its “rear-dead-center” position can result in stalling the tractor engine or disengaging the PTO. One solution has been to use a hydraulic drive to assist with baler startup, but the effectiveness of this solution is limited.
This background discussion is intended to provide information related to the present invention which is not necessarily prior art.
Embodiments of the present invention solve the above-described and other problems and limitations by providing a system for controlling a transfer of power from a tractor to a baler. More specifically, the present invention provides an integrated driveline slip clutch for a large square baler by incorporating an engage/disengage slip clutch and a clutch control into the main driveline so that startup of the baler is achieved at a controlled rate. Further, the slip clutch may continue to provide driveline and PTO protection by limiting the amount of torque transmitted to the baler during normal baler operation.
According to a first aspect of the present invention, a baler broadly includes a plunger reciprocal within a baling chamber, a driveline configured to receive mechanical power from a tractor, a flywheel configured to smooth the received mechanical power, a gearbox configured to condition the smoothed mechanical power to drive the reciprocating plunger in the baling chamber, and an integrated driveline clutch system for controlling the transfer of power from the tractor to the baler. The integrated driveline clutch system comprises a slip clutch having a plurality of clutch plates. The slip clutch is configured to be moveable between a disengaged relationship in which no power is transferred from the driveline to the gearbox, and one or more engaged relationships in each of which an amount of power is transferred from the driveline to the gearbox.
Various implementations of the foregoing embodiments may include any one or more of the following additional features.
Movement of the slip clutch between the disengaged relationship and the one or more engaged relationships may be controlled mechanically. For example, movement of the slip clutch between the disengaged relationship and the one or more engaged relationships may be controlled by a plurality of weights attached to a plurality of lever arms spaced around a perimeter of the plurality of clutch plates, and a centrifugal force provided by the turning driveshaft may cause the plurality of weights to apply via the plurality of lever arms a compressive force to the plurality of clutch plates and thereby move the slip clutch into the one or more engaged relationships. The slip clutch may further include a plurality of springs interposed between the plurality of lever arms and the plurality of clutch plates, and the springs may be configured to control the compressive force applied by the plurality of lever arms to the plurality of clutch plates.
Alternatively, movement of the slip clutch between the disengaged relationship and the one or more engaged relationships may be controlled electronically. For example, movement of the slip clutch between the disengaged relationship and the one or more engaged relationships may be controlled by an electronically controlled valve configured to introduce and remove a hydraulic fluid so as to move a clutch cylinder to act on the plurality of clutch plates and thereby move the slip clutch into the one or more engaged relationships. The system may further include an electronic controller configured to receive one or more input data signals from one or more sensors concerning operation of the baler, and based on the one or more input data signals, control operation of the electronically controlled valve. The electronic controller may be configured to cause the electronically controlled valve to introduce and remove the hydraulic fluid at a controlled rate to achieve the one or more engaged relationships, and/or the electronic controller may be configured to follow a pressure control profile in which the electronic controller causes the amount of hydraulic fluid to be ramped at the controlled rate through one or more levels to achieve the one or more engaged relationships. The slip clutch may further include a plurality of springs interposed between the clutch cylinder and the plurality of clutch plates, and the springs may be configured to control the compressive force applied by the clutch cylinder to the plurality of clutch plates.
The system may further include a gearbox shaft having a central passage in fluid communication with the clutch cylinder, wherein the hydraulic fluid is introduced into and removed from the clutch cylinder via the central passage in the gearbox shaft. Alternatively, the system may further include a double acting cylinder configured to move the clutch cylinder, wherein introduction of the hydraulic fluid into the double acting cylinder moves the clutch cylinder to apply a compressive force to the plurality of clutch plates and thereby move the slip clutch into the one or more engaged relationships. The system may further include a lever arm attached at a first end by a yoke to the clutch cylinder, and attached at a second end to the double acting cylinder, and the lever arm may be configured to transmit movement of the double acting cylinder via the yoke to the clutch cylinder.
This summary is not intended to identify essential features of the present invention, and is not intended to be used to limit the scope of the claims. These and other aspects of the present invention are described below in greater detail.
Embodiments of the present invention are described in detail below with reference to the attached drawing figures, wherein:
The figures are not intended to limit the present invention to the specific embodiments they depict. The drawings are not necessarily to scale.
The following detailed description of embodiments of the invention references the accompanying figures. The embodiments are intended to describe aspects of the invention in sufficient detail to enable those with ordinary skill in the art to practice the invention. Other embodiments may be utilized and changes may be made without departing from the scope of the claims. The following description is, therefore, not limiting. The scope of the present invention is defined only by the appended claims, along with the full scope of equivalents to which such claims are entitled.
In this description, references to “one embodiment”, “an embodiment”, or “embodiments” mean that the feature or features referred to are included in at least one embodiment of the invention. Separate references to “one embodiment”, “an embodiment”, or “embodiments” in this description do not necessarily refer to the same embodiment and are not mutually exclusive unless so stated. Specifically, a feature, structure, act, etc. described in one embodiment may also be included in other embodiments, but is not necessarily included. Thus, particular implementations of the present invention can include a variety of combinations and/or integrations of the embodiments described herein.
Broadly characterized, the present invention provides a system for controlling a transfer of power from a tractor to a baler. More specifically, the present invention provides an integrated driveline slip clutch system for a large square baler by incorporating an engage/disengage slip clutch and a clutch control into the main driveline so that startup of the baler is achieved at a controlled rate. Further, the slip clutch may continue to provide driveline and PTO protection by limiting the amount of torque transmitted to the baler during normal baler operation.
Referring to
The baling chamber 44 may be configured to receive the loose crop material 22 so that it can be compressed by the plunger 42 into the bale 24. The baling chamber 44 may be substantially rectangular in shape to facilitate the compression and forming process. The plunger 42 may be configured to compress the loose crop material 22 by moving within the baling chamber 44 in a reciprocating manner. More specifically, the plunger 42 may repeatedly extend into the forming chamber 44 to compress the loose crop material 22 that is already present therein, and then retract to allow additional loose crop material 22 to enter the forming chamber 44 for compress1On.
In a first embodiment of the present invention, an integrated driveline slip clutch system 150 may use centrifugal force to move a slip clutch between a disengaged and one or more engaged relationships. Referring to
The plurality of lever arms 156 may be arranged in a spaced-apart relationship around a perimeter of the flywheel mounting plate 152. Each lever arm 156 may present a first end, a second end, and an intermediate portion between the first and second ends. Each pivot support pin 158 may present a first end and a second end, wherein the first end of the pivot support pin 158 may be pivotably attached to the intermediate portion of a respective lever arm 156, and the second end of the pivot support pin 158 may be fixedly attached to the flywheel mounting plate 152. Each spring support pin 160 may present a first end, a body, and a second end, wherein the first end of the spring support pin 160 may be slidably associated with the first end of a respective lever arm 156 and may present a shoulder stop 166 configured to limit the inward sliding movement of the lever arm 156 on the spring support pin 160, the body of the spring support pin 160 may extend through the clutch plates of the slip clutch 154, and the second end of the spring support pin 160 may be attached to the flywheel mounting plate 152. The plurality of springs 162 may be configured to provide the appropriate force for proper clutch frictional torque. Each spring 162 may present a first end and a second end, wherein the first end of the spring 162 abuts the first end of a respective lever arm 156 and the second end of the spring 162 abuts the slip clutch 154. Each weight 164 may be pivotably or otherwise mounted to the second end of a respective lever arm 156.
The clutch system 150 may further include an outer ring 168 configured to facilitate maintaining proper alignment of other components and to better distribute forces applied via the lever arms 156. The clutch system 150 may also further include one or more additional spring support pins 170 and associated springs 172 that are not connected to lever arms 156, wherein the outer ring 168 transmits the force applied by adjacent lever arms 156 to these additional pins 170 and springs 172.
In operation, the springs 162 may be partially relaxed (or decompressed) before the PTO 32 is engaged so that at startup the slip clutch 154 slips freely with little torque transmitted. As the PTO 32 is engaged, the tractor/driveline RPMs increase, and the driveline/flywheel speed increases, centrifugal force causes the weights 164 to move radially outward. The weights 164 act on the lever arms 156 which pivot on the pivot support pins 158 attached to the flywheel mounting plate 152, so that as the weights 164 move outward, force is applied to the springs 162 through the lever arms 156. The desired torque setting is maintained as the spring force is controlled when the lever arms 156 contact the shoulders 166 of the spring support pins 160, thereby stopping inward movement of the lever arms and limiting the amount of force applied to the springs 162 and, via the springs 162, to the slip clutch 154. Thus, the centrifugal force, acting through the weights 164 and the lever arms 156, and controlled by the springs 162, may move the slip clutch 154 into the one or more engaged relationships.
In a second embodiment, the integrated driveline slip clutch system 250 may be relocated to be near or at the front of the frame 34 of the baler 28 by the gearbox 240, and may use a clutch cylinder to move a clutch between a disengaged and one or more engaged relationships. This clutch system 250 may be used only at startup, rather than providing both dual purpose engaged and slip protection. Referring to
In operation, pressurized oil or other hydraulic fluid may be introduced through the central passage 280 into the interior cavity 282 of the clutch cylinder 276 to force the clutch cylinder 276 away from the clutch 254 and thereby disengage the clutch 254 from the driveline 236.
The hydraulic fluid may then be removed from the interior cavity 282 via the central passage 280 to allow the clutch cylinder 276 to move back into contact with the clutch 254 and thereby engage the clutch 254 with the driveline 236. Thus, the hydraulic fluid, acting on the clutch cylinder 276, may move the slip clutch 254 into the one or more engaged relationships.
Referring also to
In various implementations, introduction and removal of the hydraulic to disengage and engage the clutch may be controlled by a mechanical or electronic control mechanism, such as the electronic control system 500 shown in
In a third embodiment, the integrated driveline slip clutch system 350 may again be relocated to be near or at the front of the frame 34 of the baler 28 by the gearbox 340, and may again use a clutch cylinder 376 to actuate in response to hydraulic fluid being introduced and removed through a central passage 380 through a gearbox shaft 378. However, this design may provide both protection against driveline slip and controlled engagement at baler startup. Referring to
In operation, the springs that control friction torque are also compressed by the clutch cylinder 376 pulling a rear outside pressure plate 386 away from the clutch friction surface plates 388. This opens the clutch plates 388 to allow the slip clutch 354 to slip freely. Thus, here again, the hydraulic fluid, acting on the clutch cylinder 376, may move the slip clutch 354 into the one or more engaged relationships.
In various implementations, introduction and removal of the hydraulic fluid to disengage and engage the slip clutch may be controlled by a mechanical or electronic control mechanism, such as the electronic control system 500 shown in
In a fourth embodiment, the integrated driveline clutch system 450 may be similar to that of the third embodiment but may use a double acting external control cylinder to move a slip clutch between a disengaged and one or more engaged relationships. This advantageously allows additional force to be applied to the friction clutch plates to increase the available starting torque, which may be required, for example, during hard startups of the baler 28 after a blockage. In this design, the slip clutch 454 may or may not be mounted to a flywheel.
Referring to
In operation, extension and retraction of the double acting cylinder 496 may be transmitted via the lever arm 492 and yolk 490 to the clutch cylinder 476 to, respectively, engage and disengage the slip clutch 454. The clutch cylinder 476 may be connected by a release bearing attached to the outer clutch pressure plate 486. The clutch cylinder 476 may relax after the baler 28 has started and the flywheel is at operating speed. The clutch slip torque may again be controlled by the predetermined length of the compression spring pushing on the pressure plate 486. Thus, here again, the hydraulic fluid, acting on the clutch cylinder 376, may move the slip clutch 354 into the one or more engaged relationships.
Referring also to
Referring also to
In various implementations, introduction and removal of the hydraulic fluid to disengage and engage the clutch may be controlled by a mechanical or electronic control mechanism, such as the electronic control system 500 shown in
Referring to
Referring also to
Although the invention has been described with reference to the one or more embodiments illustrated in the figures, it is understood that equivalents may be employed and substitutions made herein without departing from the scope of the invention as recited in the claims.
Having thus described one or more embodiments of the invention, what is claimed as new and desired to be protected by Letters Patent includes the following:
This application claims the benefit of U.S. Provisional Application No. 62/272,536 filed Dec. 29, 2015, which is hereby incorporated by reference in its entirety.
Filing Document | Filing Date | Country | Kind |
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PCT/US2016/068079 | 12/21/2016 | WO | 00 |
Number | Date | Country | |
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62272536 | Dec 2015 | US |