The invention relates to cutting reel units for mowers, and particularly, user interface and control systems for cutting reel mechanism, and methods for adjusting cutting reel units.
Conventional mowing machines have an attached cutting reel unit or multiple units. Such machines typically move the cutting reel unit across the ground adjacent to the machine. Grass beneath the cutting reel unit is mowed as the machine travels forward. Conventional reel mower vehicles can include a plurality of arm members that extend from the vehicle, each arm having a cutting reel unit attached to its outer end portion.
The cutting reel units typically include front and rear skids or rollers that support or carry the cutting reel unit across the surface of the ground during mowing operation. Such vehicles and cutting reel units are disclosed for example in U.S. Pat. Nos. 5,343,680; 5,412,931 and 5,459,984.
Conventional cutting reel units provide a plurality of blades coupled together to form a generally cylindrical reel that rotates about a transverse axis. The blades pass in close proximity to a bedknife to create a scissoring action for cutting vegetation such as grass. A frame typically houses the reel and bedknife. Wheels, rollers or skids are coupled to the frame for engaging or rolling across the ground to operatively support the reel and bedknife at a predetermined height above the ground. The height at which grass is cut or “height-of-cut” is therefore determined by the height at which the wheels, rollers or skids carry a frame, reel and bedknife above the ground. Cutting reel units are typically used for mowing golf courses or other areas where an accurate cut is desirable.
To produce a high quality cut, and a cut that is even for multiple cutting reel units and across mowing passes by a machine with multiple cutting reel units, it is necessary that the height-of-cut for each cutting reel unit be properly adjusted. It is known that reel mowers have an adjustment mechanism for adjusting the reel mowing height.
For height-of-cut adjustments, there is a generally accepted and common method for determining a cutting reel unit's existing height-of-cut and how far it needs to be adjusted towards a targeted adjustment. The procedure for setting the cutting height typically involves fastening a gauge bar to the bedknife such that the upper surface of the bar is parallel to a forward, horizontal position of the bedknife and at the desired distance below the cutting edge of the bedknife. The front and rear rollers are then manually adjusted to come into contact with the upper surface of the gauge bar.
Cutting reel units cut properly only if the reel-to-bedknife clearance is properly adjusted. Currently, the reel-to-bedknife clearance is manually adjusted. The adjustment is made on a regular basis, typically before use, or made during or after use when poor cut quality is detected. Sometimes the adjustment is made such that the reel touches the bedknife and then the reel and bedknife are allowed to wear into place. Adjustments are also made after repair or replacement of the reel or bedknife.
Specifically, the reel-to-bedknife clearance is adjusted by moving the reel away from the bedknife to allow a specific gap—that is even across the length of the reel and bedknife—between both the reel and bedknife. The gap is then measured by inserting a feeler gauge (of the same thickness as the adjustment gap) between the reel and bedknife. The adjusted gap between the reel and bedknife is determined to be accurate when the feeler gauge can be moved smoothly between the reel and bedknife across the entire length of the reel and bedknife, such that there is only a slight drag of the feeler gauge as it is moved across this length. To verify reel and bedknife sharpness and a correct reel-to-bedknife adjustment, a single strip of paper is often inserted between the reel blade and bedknife while the reel is turned forward by hand. If the reel cuts the paper, the sharpness and adjustment are usually determined to be correct. The quality of the cut of the piece of paper across the single sheet can be examined to indicate whether the clearance is correct.
Reel adjustments are also necessary when a cutting reel unit is “re-tasked,” in effect, adjusted for cutting another type of grass or grass to be cut to a different height. For example, a cutting reel unit could be re-tasked from an adjustment appropriate for a golf course fairway to adjustment appropriate for a golf course green, the two areas having different grass height requirements. However, re-tasking a cutting reel unit is time-consuming. This is especially true considering that for large area grass cutting, such as on a golf course, multiple cutting reel units are typically associated with each reel machine or vehicle. To avoid re-tasking cutting reel units, many golf courses have cutting reel units or cutting machines which remain designated or pre-adjusted for particular grass requirements, in effect, a designated group of cutting units for different areas of the golf course. This technique necessitates multiple cutting units or cutting machines. Multiple cutting units or machines can result in higher capital costs and maintenance costs.
The present inventors have recognized that proper mower adjustments such as height-of-cut and reel-to-bedknife clearance are time consuming, labor intensive and often hard to achieve through manual adjustment methods.
The present inventors have recognized that the adjustment time, and the accuracy and precision of these adjustments, can be improved through an automated adjustment system.
The present inventors have recognized that a need exists for dynamic adjustment capability for multi-area mowers or mowers that are capable of mowing multiple areas having different cutting requirements.
The present inventors have recognized the need to improve the adjustment process to ensure a shorter required adjustment time, ease of adjustment, and improved reel operation quality.
The invention provides a control system for adjusting the reel of a cutting reel unit. The cutting reel unit may be carried by, or attached to, a vehicle, such as a tractor, singularly or as one of a plurality of cutting reel units, or may be incorporated into a riding mower, a walking mower or a ride-on mower, also singularly or as one of a plurality of cutting reel units. The cutting reel can be one driven in rotation by one or more hydraulic motors, electric motors, by the traction drive of the mower machine or vehicle, or by other type drive.
The invention provides a user interface that is adapted for selecting and initiating reel adjustments, for selecting reel parameters or adjustments, for calibrating and re-tasking a reel unit or units, for inputting pre-selected adjustment values, and/or for making fine adjustments to pre-selected reel adjustments.
The control system can control reel-to-bedknife clearance, height-of-cut, lateral leveling of the reel, and the reel rotational speed.
The invention provides a control system for adjusting the reel of a cutting reel unit, that includes a cutting reel, a frame supported by at least one support element that is supported on, and is movable along, the ground, the frame supporting the cutting reel, a bedknife carried on the frame, at least one first actuator adjustable to set a clearance between the reel and the bedknife, a controller that is signal-connected to the actuator, to adjust the actuator; and an operator input station that is signal-connected to the controller, the operator input station or “user interface” comprising an input portion, such as a keypad portion, and a display portion, wherein the clearance is indicated on the display portion and the clearance can be selectively changed via the controller by operator input to the input portion.
According to another aspect of the invention, a control system can provide a height-of-cut adjusting system including a frame supported on at least one support element that is supported on, and is movable along, the ground, a cutting reel carried on the frame, a bedknife carried on the frame, the reel and the bedknife defining a cutting line therebetween, an actuator operatively connected between the frame and the bedknife and arranged to adjust the elevation of the cutting line to set a height-of-cut of the cutting reel unit, a controller that is signal-connected to the actuator, and an operator input station that is signal-connected to the controller, the operator input station or “user interface” comprising an input portion, such as a keypad portion, and a display portion, wherein the height-of-cut is indicated on the display portion and the height-of-cut is selectively changed by operator input on the input portion.
The control system can include the reel-to-bedknife adjusting system and the height-of-cut adjusting system, as described in the preceding two paragraphs, reel leveling by adjusting the height-of-cut independently on opposite ends of the reel, and reel rotational speed selection in one control system.
The operator input station can be permanently mounted with the controller to be transported with the cutting reel unit during operation.
The clearance and/or height-of-cut can be re-set to a predetermined value by the activation of a button on the input portion.
The clearance and/or height-of-cut can be selected from a list of selectable clearances and/or heights-of-cut displayed on the display portion using the input portion.
The clearance and/or height-of-cut can be manually changed by operator input to the input portion.
A contact sensor for sensing contact between the reel and the bedknife, can be provided wherein after the one selectable clearance is selected as the clearance, the controller is configured to instigate a routine wherein the reel and bedknife are brought together until contact is sensed by the contact sensor and then the controller adjusts the actuator to separate the reel from the bedknife by the clearance.
The input portion of the operator input station can include a reset or setup button which calibrates the position of the second actuator and a measured height-of-cut reference position. This position of the actuator is preferably the stalled position of the actuator wherein the bedknife is urged against a height-of-cut measuring bar.
The cutting reel unit control system can be implemented through a variety of control architectures such as distributed control or centralized control. The control protocol can be CAN, serial, or other control protocols.
The cutting reel unit control system can be automatically self-adjusting, which periodically corrects the reel adjustments such as the reel speed, the height-of-cut, the reel lateral leveling, and the reel-to-bedknife clearance. The control system can also automatically correct the reel-to-bedknife clearance if contact between the reel and bedknife is sensed during operation.
The cutting reel unit control system can be configured as a central controller or by controllers located at each cutting unit, or even by a local controller designated for each actuator. The operator input system can be mounted with the controller(s) on a mowing vehicle to be signal-connected on a permanent basis with the controller(s), or can be a separate operator input station that is connectable to multiple controllers to initiate adjustments, and can thereafter be disconnected from the controller(s) and removed from the mowing vehicle. The cutting reel unit control system can be adjusted after operator or automatic initiation of an adjustment routine in a central controller or by operator or automatic initiation of control routines performed by controllers at each cutting unit or at each actuator.
The cutting reel unit adjustment can be made by a controller external to the cutting unit, such as by a control unit that is used in a shop to re-adjust or re-task a cutting unit for a pre-selected grass condition or area and desired height-of-cut.
The disclosed invention provides advantages in that the apparatus and method allow for rapid and automatic adjustment of the reel-to-bedknife gap without operator intervention following operator initiation of the adjustment. The reel can be adjusted in seconds. The method has speed and consistency advantages over manual adjustment, and does not require detection of poor cut quality or excess surface wear in order to perform the automatic adjustment.
The disclosed invention provides advantages in that the apparatus and method allow for rapid and automatic adjustment of the height-of-cut of a reel of a cutting reel unit without operator intervention following operator initiation of the adjustment. The reel can be adjusted in seconds. The method has speed and consistency advantages over manual adjustment, and does not require detection of poor cut quality in order to perform the automatic adjustment.
By making these adjustments automatically, the reel adjustment process may be accomplished more consistently without the presence of a skilled mechanic. The automated adjustment also provides the capability for the support of autonomous equipment.
The control system allows a cutting reel unit or units to be rapidly re-tasked to cut different grass heights for different areas of a golf course. The system allows a single cutting reel unit to be readily usable for multiple golf course areas.
Numerous other advantages and features of the present invention will be become readily apparent from the following detailed description of the invention and the embodiments thereof, from the claims and from the accompanying drawings.
While this invention is susceptible of embodiment in many different forms, there are shown in the drawings, and will be described herein in detail, specific embodiments thereof with the understanding that the present disclosure is to be considered as an exemplification of the principles of the invention and is not intended to limit the invention to the specific embodiments illustrated.
The inside frame 18 is carried by an outside frame 22. The outside frame 22 is supported on front and rear rollers 24, 26 respectively. The inside frame 18 is supported on the outside frame 22 by actuators 30, 32 and by struts 36, 36. The struts 36, 36 are substantially mirror-image identical in configuration. A pushing or towing frame 42 is arranged between the inner and outer frames 18, 22. The towing frame 42 includes vertical plates 44, 46 fastened to side plates 52, 54 of the outer frame 22 by pins 56, 58 residing in slots 52a, 54a. The slots 52a, 54a are part of a mechanism which permits the reel to be pushed from the rear when rolling, and still touch down heel first when lowered.
A crossbar 48 connects the side plates 44, 46. A vehicle connector or lift arm can be engaged at a select position along the crossbar 48 to tow or push the cutting unit 10 along the ground during the cutting operation.
The outside frame 22 also includes adjustable bracket members 62, 62 connected by fasteners 66 to a respective side plate 52, 54. The bracket members 62, 62 are substantially mirror-image identical in configuration. The members 62, 62 extend downward to be connected via plates 72, 72 to front support assemblies 76, 76 that are supported by the front roller 24. The front support assemblies 76, 76 are substantially mirror-image identical in configuration.
Plates 84, 84 connect the outer frame side plates 52, 52 to rear support assemblies 88, 88 that are supported by ends of the rear roller 26. The rear support assemblies 88, 88 are substantially mirror-image identical in configuration.
The inside frame 18 includes side plates 106, 106 connected together by crossbars 112, 114. The side plates 106, 106 are substantially mirror-image identical in configuration. A grass deflector plate 118 is arranged between the bars 112, 114 above the reel 12. The side plates each include a front flange 122. A tube 126 is welded to each of the front flanges 122. A tube 132 is also welded to each of the members 62b. Sleeve bearings 140 are fit into each tube and a pin, bolt or other fastener 142 is used to pivotally connect each of the angled struts 36 to a respective pair of tubes 126, 132.
Thus, extension of the rods 30c from the housings 30b, of the actuators 30, 32, lifts the inside frame 18 with respect to the outside frame 22. Retraction of the rod 30c into the housing 30b, of the actuators 30, 32, lowers the inside frame 18 with respect to the outside frame 22.
The struts 36, 36 (
Actuators 202, 204 are provided on a front side of the inside frame 18 adjacent opposite ends of the reel 12. As illustrated in
Each reel bearing housing 216 is pinned to a respective side plate 106 by a pin or fastener 230. The extension or retraction of the rods 202c, 202c with respect to the housings 202b, 202b of the actuators 202, 204, pivots the reel bearing housings 216, 216 about the pins or fasteners 230, 230. As illustrated in
The rod 202c is a substantially hollow cylinder and includes a rod end portion 274 fixed to a rod body portion 276 by threaded mutual engagement. The lead screw 260 extends substantially through the body portion 276. A lead nut 280 is fixed to the rod body portion 276. An anti-backlash nut 288 is threaded onto the lead screw 260. The anti-backlash nut 288 also includes Acme threads, preferably plastic, and engaged to the external threads of the lead screw 260. The anti-backlash nut 288 includes a convex conical tapered surface 290 which abuts a concave conical tapered surface 292 of the rod body portion 276 or the lead nut 286 fixed to the rod body portion 276.
A coil spring 296 surrounds the lead screw 260. The coil spring 296 is connected to the anti-backlash nut at one end 296a and to the rod end portion 274 at an opposite end 296b.
The anti-backlash nut 288 and the spring 296 can be eliminated in the actuators 30, 32 where fine positioning accuracy is not required. The anti-backlash feature is most advantageous for the actuators 202, 204 where fine positioning accuracy is desired.
The motor drive 202a includes a casing 297 that encloses windings 298, bearings 308, and an optical encoder 310. The encoder 310 includes a target disk 312 and a read head 314. The read head 314 includes two spaced-apart light emitting and reading devices, used to determine position of the rotating target disk and also its direction of rotation. The read head 314 is signal-connected to a circuit board 315 that is signal-connected via a plug 316 and a cable or wiring to the controller 300.
To set absolute position of the rod, the rod can be extended or retracted by the stepper motor 266 to maximum or minimum extension, until the motor 266 stalls. At this position, the encoder will send no more pulses to the controller since the target disk stops rotating. This sets the maximum extension or maximum retraction. The stepper motor 266 can then be reversed and selectively driven a pre-selected amount to properly position the rod end portion 274.
The cutting reel unit control system can also be automatically self-adjusting, which periodically corrects the reel adjustments such as the reel speed, the height-of-cut, the reel lateral leveling, and the reel-to-bedknife clearance, or corrects the reel-to-bedknife clearance if contact between the reel and bedknife is sensed by the detector 320 during operation.
The cutting reel unit control system can be configured as a central controller or by controllers located at each cutting unit, or even by a local controller designated for each actuator. The controller or controllers are responsive to the operator input station 306. The cutting reel unit control system can be adjusted after operator initiation or automatic initiation of an adjustment routine in a central controller or by operator initiation or automatic initiation of control routines performed by controllers at each cutting unit or at each actuator.
The cutting reel unit adjustment can be made by an operator input station or interface 306 that can be on board the vehicle moving the cutting reel unit, or can be external to the cutting reel unit, such as by an operator input station that is used in a shop to re-adjust or re-task a cutting unit for a pre-selected grass condition or area and desired height-of-cut. The controller 300 can also be external to the cutting unit for shop adjustment of the cutting reel unit.
The cutting reel adjustment can also be initiated by the controller responsive to an external sensor such as a height of grass sensor, or responsive to a location sensor and/or sender on the cutting unit or cutting machine that communicates with an external ground-based system or a global positioning system (GPS). These systems, responsive to external conditions, along with the onboard control systems as described herein facilitate implementation of the control system in either a manned cutting machine or an autonomous cutting machine.
For example, different areas of a golf course could be mapped electronically and preprogrammed into the onboard or remote controller and such controller could communicate with the external positioning system and thereafter adjust the actuators to adjust the cutting unit for the type of grass, the area, and desired cut lines for corresponding areas of the golf course.
The operator, via the input station 306, or the controller responsive to an automatic routine, can command the reel rotating speed and direction of rotation to the reel motor 16. A reel speed sensor 330 can be associated with the reel 12 or with the reel motor 16, or with other associated rotating element to communicate reel speed to the controller 300. The speed sensor 330 can be a known type that senses speed by magnetic or optical targets that rotate with the reel, motor or other rotating element that are sensed by a stationary sensor. The controller can be signal-connected to a system 350 that controls the speed and direction of rotation of the reel motor 16 to adjust the speed and direction of rotation of the reel 12. When a hydraulic motor is used, the system 350 can include speed and direction of rotation control of a hydraulic pump 352 that drives the hydraulic motor and/or flow control of valving 354 that diverts hydraulic fluid away from the motor 16 to adjust speed and/or reverses hydraulic fluid flow to change direction of rotation of the motor 16. The controller 300 can adjust the speed of the reel 12 based on grass length or type of grass given operator or other input.
The speed information from the speed sensor 330 can be operator-accessible by the interface 306 and adjusted by operator selection of a choice of pre-selected speeds or by manual adjustment.
The operator, via the input station 306, or the controller responsive to an automatic routine, can command adjustment of the height-of-cut, say in mm, and can command the automatic adjustment of the reel-to-bedknife clearance. For adjusting the reel-to-bedknife gap as explained below, by operator or automatic initiation the controller can command the reel motor 16, such as via the system 350, to spin the reel 12 in a reverse direction before initiation of the adjustment procedure by the operator. The actuator pairs 30, 32; 202, 204 can be adjusted individually to set a desired lateral degree of either the height-of-cut level or the reel-to-bedknife clearance. A position signal S1 from each actuator read head 314 is communicated to the controller 300, and an appropriate drive signal S2 is sent to the stepper motor 266 of each actuator via appropriate signal conditioning and/or amplification to position rod end portions 274 with respect to the respective actuator body 30b, 202b of the actuators 30, 32, 202, 204.
The detector 320 (
According to an exemplary embodiment, the detector or detectors 320, such as in the form of a microphone or microphones, can be located within the casing 297 of the motor drive 202a of one or both of the actuators 202, 204 (see
According to one method, wherein the noise produced by the reel is sensed by a microphone, or alternately by an accelerometer, the resulting vibration is analyzed to detect the presence or absence of contact.
The algorithm used to analyze the noise is designed to detect a particularly prominent resonance point in the sensed sound when the reel and bedknife are clicking. The resonance is detected by using a single frequency range power spectral density (psd) estimate of the signal power. The single range method calculates the psd at only a single narrow frequency range (or bin) of interest. Reducing the psd algorithm in this way significantly lessens the computational effort needed versus the full psd. This style of algorithm is used to reduce sensitivity to spurious environmental noise. The resonance can also be detected in using an analog or discrete switched capacitor narrow bandpass (or notch) filter, rectifying the filter output, and then detecting the DC level of the resulting signal.
Alternately, a simple algorithm that senses the increased noise level when the reel and bedknife are in contact can be used, but this algorithm can be sensitive to environmental noise.
A method of precisely positioning the reel 12 with respect to the bedknife 14 using the sound detector(s) 320 is set forth in
The steps of one method of the invention comprise:
1. registering adjustment mechanisms 202, 204 by moving the reel adjustment mechanisms 202, 204 to known positions, particularly, moving the rods 202c to known positions with respect to the bodies 202b using the drive motors 202a;
9. after the accurate distance y is set at both ends of the reel, moving both ends of the reel toward the bedknife by the difference between the pre-defined distance y and the pre-selected gap width, (y minus gap width) to set the pre-selected gap width between the reel and the bedknife. By first accurately setting the pre-selected reel-to-bedknife clearance y as a penultimate setting, and then subsequently reducing this clearance to the smaller gap width, the detection accuracy of the method is enhanced because contact between the reel and bedknife during the click detection cycle is more likely to be limited to contact at the extreme ends of the reel. The resulting gap width between the reel and the bedknife can be in the range of, but not limited to, about 0.001 to 0.003 inches.
Other methods encompassed by the invention are possible. Method step 1 above can be eliminated. Method step 2 can be eliminated, or can be modified wherein the reel 12 is spun in the normal operating direction. Method step 3 can be modified wherein the reel 12 is moved away from the bedknife 14 a pre-selected distance on both ends of the reel. Method steps 5 and 7 can be modified wherein the small pre-defined distance y can be equal to the actual gap width and method step 9 can then be eliminated.
Furthermore, although the steps refer to moving the reel toward or away from the bedknife, this is to be interpreted as relative movement, such relative movement would also encompass moving the reel toward or away from a stationary bedknife, moving the bedknife toward or away from a stationary reel, or moving both reel and bedknife toward and away from each other.
“calibrate cut height”, to calibrate a cut height with a position of the actuators 30, 32 for any reel;
The height-of-cut function is controlled by the following buttons and process:
The reel height preferences can be changed using the
Register the stepper motors by stalling the stepper motors against their respective stops (all the way retracted).
Enter the height of the calibration bar (unless this never changes).
Stall the stepper motors against the calibration bar and read the encoder counts.
Calculate the new offset for the curve fit that translates number of encoder counts to height-of-cut (and the other way around).
Store the value of the offset for each stepper motor to non-volatile memory (or use a battery backup system to keep memory powered).
Another method of calibrating the height-of-cut includes the steps of:
The control systems of the invention includes an effective operator input station for precise and quick adjustment and/or re-tasking of reel units, particularly for multiple reel units that are usefully deployed on variable terrains of a golf course.
The controller 300 and/or the interface 306 make more feasible additional aspects of the invention. It would be useful to know how many times a reel has been sharpened to estimate the remaining life of the reel and/or bedknife. In this regard, the number of actuator registrations and/or calibrations of the reel-to-bedknife clearance for each reel unit can be recorded into controller memory or in a memory provided in the interface 306, designated for the particular reel unit. Alternately, a designated function, manual or automatic, for noting and recording each sharpening event, can be provided by the interface 306. This information can be operator-accessible via the interface 306.
By using the detector 320, the reel speed may be determined by counting the number of clicks per time period when the reel is making contact with the bedknife, or by sound monitoring during operation. The sound monitoring can be based on variations in sound pressure level or based on characteristics of the sound signal received by the detector 320, i.e., amplitude, frequency, etc. By using the sensor for speed sensing, it may be possible to eliminate the speed detection sensor 330 as a manufacturing cost savings.
From the foregoing, it will be observed that numerous variations and modifications may be effected without departing from the spirit and scope of the invention. It is to be understood that no limitation with respect to the specific apparatus illustrated herein is intended or should be inferred.
This application claims the benefit of Provisional Application 60/486,050 filed Jul. 10, 2003.
Number | Date | Country | |
---|---|---|---|
60486050 | Jul 2003 | US |