Riding lawnmower

Abstract

The purpose is to facilitate the discharge of turfgrass in a lawnmower equipped with a turfgrass collector that can be raised and lowered. [Solution] A riding lawnmower is provided with a mower 5 having a cutting blade 4 on a traveling vehicle body 1, and a collector 32 for collecting cut grass is configured to be able to be raised and lowered and dumped. The mower is equipped with a height detection means 76 for detecting the height to which the collector 32 has been raised, and a storage means 78 for storing the detected height H. When the collector raising and lowering operation unit 54, 74, 79U is operated, the collector 32 is raised to the stored position. The height detection means 76 is configured to detect the collector height H when the dump operation is performed, or to output a height H arbitrarily set by the operator.

Description

Technical Field

[0001] The present invention relates to a riding lawn mower provided with a grass collector that can be raised and lowered.

Background Art

[0002] Conventionally, the grass collection container has been raised and lowered by tilting a joystick lever in the front-rear direction, or dumped and returned to its original state by tilting it in the left-right direction (Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] When discharging grass from the collector to a truck or a collection vehicle, if the position of the collector at the time of discharge is low, it will contact the vehicle, and if it is too high, the grass will be blown away by the wind and is likely to spill. Therefore, it is desirable to adjust to an appropriate height at the time of discharge, but it was necessary to adjust the height every time when discharging to the same place or the same vehicle.

[0005] In the present invention, in a lawn mower provided with a grass collector that can be raised and lowered, the aim is to facilitate the discharge of grass.

Means for Solving the Problems

[0006] To solve the above problems, the present invention has taken the following technical means.

[0007] The invention described in claim 1 is a riding lawnmower equipped with a mower 5 having a cutting blade 4 on a traveling vehicle body 1, and a collector 32 for collecting cut grass that is configured to be able to be raised and lowered and to be able to be dumped, wherein the mower is equipped with a height detection means 76 for detecting the height to which the collector 32 has been raised and a storage means 78 for storing the detected height H, and the collector is configured to raise the collector 32 to the stored position when the collector raising and lowering operation units 54, 74, 79U are operated.

[0008] The invention described in claim 2 is the invention described in claim 1, wherein the height detection means 76 is configured to detect the collector height H when a dump operation is performed.

[0009] The invention described in claim 3 is the invention described in claim 1, wherein the height detection means 76 is configured to output a height H arbitrarily set by the operator.

[0010] The invention described in claim 4 is the invention described in claim 1, wherein a rear camera 71 is provided at the rear of the vehicle body 1, at a position that moves up and down with the raising and lowering of the collector 32, and the camera image is displayed on the display panel 60, and the grass discharge area Z is displayed on the imaging screen 72 of the rear camera 71 when the collector 32 is raised.

[0011] The invention described in claim 5 is the invention described in claim 1, further comprising a lift lever 75 that controls the raising and lowering of the collector 32, and one-touch operating means 74, 79U that raise the collector to a height H stored in the storage means 78.

[0012] The invention described in claim 6 is the invention described in claim 5, further comprising a one-touch operating means 79D for lowering the collector 32 back to its storage position. [Effects of the Invention]

[0013] According to the inventions described in claims 1 to 3, the storage height can be raised arbitrarily or to a detected storage height position, making it easy to perform the discharge operation.

[0014] According to the invention described in claim 4, in addition to the effects described in claim 1, it has the function of being able to image the rear of the vehicle body 1 when the collector is lowered and stored, and when the collector is raised, the discharge position when the collector is raised can be confirmed, so that the discharge operation can be easily performed.

[0015] According to the invention described in claim 5, in addition to the effects described in claim 1, the device can be raised to the stored height position each time using a one-touch operating means, making the discharge operation easier.

[0016] According to the effect described in claim 6, in addition to the effect described in claim 5, the device can be returned to the storage position with a one-touch operation means, making operation easy. [Brief explanation of the drawing]

[0017] [Figure 1] This is a side view of a riding lawnmower according to an embodiment of the present invention. [Figure 2] This is a plan view of a riding lawnmower according to an embodiment of the present invention. [Figure 3] This is a side view showing an overview of the grass discharge process of a riding lawnmower according to an embodiment of the present invention. [Figure 4] (A) A perspective view of the mower of a riding lawnmower according to an embodiment of the present invention, and (B) A power transmission diagram of the working motor of a riding lawnmower according to an embodiment of the present invention. [Figure 5] This is a power transmission diagram of the travel mechanism of a riding lawnmower according to an embodiment of the present invention. [Figure 6] This is a control block diagram of a riding lawnmower according to an embodiment of the present invention. [Figure 7] This is a plan view of an example of the handle post and main display unit of a riding lawnmower according to an embodiment of the present invention. [Figure 8] (A)(B) These are plan views showing an example of a sub-display unit of a riding lawnmower according to an embodiment of the present invention. [Figure 9] This is a flowchart of a riding lawnmower according to an embodiment of the present invention. [Figure 10] This is a control block diagram of another example of a riding lawn mower according to an embodiment of the present invention.

Embodiments for Carrying out the Invention

[0018] Hereinafter, embodiments of the present invention will be described based on examples shown in the drawings.

[0019] The front and rear of the traveling vehicle body 1 are provided with front wheels 2L and 2R and rear wheels 3L and 3R respectively. Below the front part of the vehicle body 1 and in front of the front wheels 2L and 2R, a mower 5 for cutting grass having a cutting blade 4 is provided so as to be able to move up and down, constituting a so-called front mower. On the floor 6 part above the front part of the vehicle body 1, a handle post 7 also called a column or the like is erected, and a steering steering handle 8 is provided at the upper part of the post 7. Also, a driver's seat 9 also called a cockpit is provided behind the steering handle 8.

[0020] Regarding the frame configuration of the vehicle body 1 in detail, from the front side, it consists of a floor frame 10 that supports the floor 6, the driver's seat 9, etc., and a pair of left and right side frames 14L and 14R that support a motor control unit 13 also called a battery 12 for a motor and a motor drive unit or the like.

[0021] The floor frame 10 is formed in a U shape in plan view at the front side, supports the column 7 at the front part, and is provided at the rear part to support an operation box such as the cockpit 9 and various levers. The side frames 14L and 14R are configured to support the left and right support column parts 15L and 15R of the safety guard 15, and the upper ends of these left and right support column parts 15L and 15R are connected by a head frame 15H.

[0022] An upper frame 17 is formed at a slightly higher position at the upper part of the side frames 14L and 14R. The upper frame 17 is formed in a U shape in plan view, with the curved part facing backward and the left and right front ends connected to the nearby frames.

[0023] As shown in Figures 1 and 2, a collector 32 for collecting mowed grass is provided behind the safety guard 15 and above the upper frame 17. The collector 32 is connected to the safety guard 15 via a lifting link 33, also called a lifting link, which consists of two parallel links, and is configured to be able to move up and down relative to the upper frame 17 by extending and retracting an electrically operated collector lift cylinder 33C. Furthermore, when the electrically operated collector dump cylinder 34C is extended, the front part rises with the rear center rising and dumping occurs, and the rear cover 34 opens to discharge the grass inside.

[0024] As shown in Figure 3, the collector 32 consists of a housing portion 32a and a collector frame 32b. The collector frame 32b is directly linked to the lifting link 33, and the housing portion 32a is rotatably connected to the collector frame 32b so that its front end rises around a rear horizontal support shaft 32s. The base end of the collector lift cylinder 33C is provided using the left and right support columns of the safety guard 15 of the vehicle body 1, and the other end is connected to the lower link of the parallel link that constitutes the lifting link 33. One end of the collector dump cylinder 34C is connected to the collector frame 32b, and the other end is connected to an appropriate location on the lower edge of the housing portion 32a. A receiving cylinder 32c is provided at the lower front of the housing portion 32a to correspond to the upper end of the chute 36, which will be described later.

[0025] As shown in Figure 4, gear cases 21L and 21R are provided on the upper left and right sides of the mower deck 20 of the mower 5, and the left and right cutting blade shafts 23L and 23R, each mounted with a cutting blade 4 for cutting grass, are vertically supported in these gear cases. The transmission mechanisms inside these left and right gear cases 21L and 21R are connected by a transmission shaft 24, and the left and right cutting blade shafts 23L and 23R are driven by a work motor 25, which will be described later and is linked to the transmission mechanism inside the left gear case 21L.

[0026] A chute 36 leading to a collector 32 is provided at the rear center of the mower deck 20, and the grass cut by the cutting blades 22 at the bottom of the mower deck 20 is transported into the collector 32 by the suction power of the blower 35.

[0027] The driving force of the work motor 25 is transmitted to the left cutting blade shaft 23L, which is pivotally supported vertically downward in the left gear case 21L, and further transmitted from the left gear case 21L via the transmission shaft 24 to the right cutting blade shaft 23R, which is pivotally supported vertically downward in the right gear case 21R, thereby driving it.

[0028] As described above, side frames 14L and 14R are provided, the battery 12 is placed on top of them, and the motor control unit 13, housed in a casing, is mounted on top of that. Electrodes for the motor are provided on the top surface of the battery 12 and covered by the motor control unit 13, with the cords extending from the side of the motor control unit 13 and being routed. The battery 12 may also be divided and installed on the left and right sides of the driver's seat 9 above the front wheels 2L and 2R, and covered with a cover. Furthermore, it is preferable to provide a DC battery in addition to the drive battery 12 for powering lights and other purposes. The cords from the battery 12 and the motor control unit 13 to the work motor 25 are routed along the outer surface of the chute 36.

[0029] Figure 5 shows the power transmission system for the left and right front wheels 2L, 2R and rear wheels 3L, 3R, which serve as drive wheels. Power is transmitted from the front wheel drive motor 40, which is a driving motor with its output shaft facing forward, to the left and right front wheels 2L, 2R via the front differential mechanism 41 and left and right reduction mechanisms 42L, 42R. Power is transmitted from the rear wheel drive motor 43, which is a driving motor with its output shaft facing rearward, to the left and right rear wheels 3L, 3R via the rear differential mechanism 44 and left and right reduction mechanisms 45L, 45R. The rotation of the front wheel drive motor 40 is detected by the front axle rotation sensor 46F, and the rotation of the rear wheel drive motor 43 is detected by the rear axle rotation sensor 46R. Since the front wheel drive motor 40 and the rear wheel drive motor 43 are positioned inside the front and rear axles, the length of the vehicle body 1 is not increased.

[0030] Alternatively, the left and right front wheels (2L, 2R) and the left and right rear wheels (3L, 3R) may each be configured with separate wheel-operated electric motors.

[0031] Figure 6 is a control block diagram of each motor and electric cylinder. Power from the battery 12 is controlled by the motor drive unit 13 and supplied to the front wheel drive motor 40, the rear wheel drive motor 43, the work motor 25, and the blower motor 47 that drives the blower 35. Of these, the rotation speed of the drive motors, the front wheel drive motor 40 and the rear wheel drive motor 43, is controlled by the drive operation unit 51, which includes increase / decrease buttons and a reciprocating operation lever. The drive stop and rotation speed control of the work motor 25 that drives the cutting blade 4 are controlled by the work operation unit 52, and the drive stop and rotation speed control of the blower motor 47 are controlled by the blower operation unit 53.

[0032] Furthermore, power is supplied to the mower lift cylinder 5C, the collector lift cylinder 33C, and the collector dump cylinder 34C, which are controlled by the motor drive unit 13 to raise and lower the mower 5. The raising and lowering of the mower 5 is performed by the mower lifting operation unit 54, also known as the collector lifting operation unit. The raising and lowering and dumping operations of the collector 32 are performed by the collector lifting operation unit 55 and the collector dump operation unit 56.

[0033] Furthermore, power is supplied from the DC battery 49 to the motor control device 50, which is also called a light or motor control ECU.

[0034] The motor control device 50 receives rotational speed input from the front axle rotation sensor 46F and the rear axle rotation sensor 46R, and inputs operation signals from the travel operation unit 51, work operation unit 52, blower operation unit 53, etc. It also receives operation signals from the collector lifting operation unit 54 and the collector dump operation unit 56.

[0035] The motor control device 50 performs the following control:

[0036] First, when the vehicle body 1 is decelerated or braked, regenerative power is charged to the battery 12 from the front-wheel drive motor 40 and the rear-wheel drive motor 43. When switching from four-wheel drive to two-wheel drive, the non-driving motor is switched to power generation mode, and regenerative power is charged to the battery 12.

[0037] When the operating unit 52 is switched from on to off and the operating motor 25 stops rotating, it switches to power generation mode to adjust the braking stop time, and regenerative power is charged to the battery 12. Also, when the cutting blade is rotated by an external force, it switches to power generation mode and regenerative power is charged to the battery 12.

[0038] Incidentally, the load status of the work motor 25 is displayed on a display panel 60 located on the upper surface of the handle post 7. Specifically, the display panel 60 includes a color liquid crystal display unit 61, left and right lamp groups 62L and 62R that indicate left / right turns, parking, etc. by turning various symbol lamps on and off, and an indicator 63 that can illuminate multiple sections in a strip. Of these, the liquid crystal display unit 61 is configured to switch between a main display state and a sub-display state. In the main display state shown in Figure 7, it includes a battery level display unit 64, an operating cumulative time display unit 65 that displays the cumulative time during which either the front wheel drive motor 40, the rear wheel drive motor 23, or the work motor 25 is driven, an integrated power-on time display unit 66, etc., and in the center of the liquid crystal screen is a motor shaft rotation speed display unit 67 for the work motor 25.

[0039] The indicator 63 displays the workload level. As the workload increases, the indicator 63 lights up sequentially from the edges towards the center, and the more lights that illuminate, the higher the workload level. In this embodiment, indicators 63L and 63R are arranged symmetrically on the left and right sides, and the lights on the center side illuminate sequentially as the workload level increases.

[0040] The aforementioned workload level is calculated based on the magnitude of the load current value of the work motor 25. The higher the load current value, the higher the workload level, and the number of indicator lights 63 are pre-set based on this workload level.

[0041] Next, an example of the sub-display state of the liquid crystal display unit 61 will be described. When a vehicle reverse signal is input in response to a driving control device, such as the forward / reverse gear shift pedal 70 signal, the left half of the liquid crystal display unit 61 switches to display the image capture screen 72 of the rear camera 71, and the right half switches to display the collector lift / lower indicator along with status indicators 73 such as the battery level (Figure 8(A)). Here, the rear camera 71 image can show the image capture state (in the example figure, it shows a transport truck T) along with an estimated driving trajectory Y that takes steering operations into account, indicated by a dashed line. The collector lift / lower indicator becomes a "one-touch lift / lower" display, and the collector 32 can be raised to a preset height or to a height set by the lift lever 75, which serves as the collector lift / lower operation unit, by tapping (one-touch operation means).

[0042] The height of the collector 32 is detected by a lift sensor 76, also known as a potentiometer-type lift sensor, which is provided at the base end of the lifting link 33 of the collector 32 on the vehicle body 1 side. The control unit (not shown) is configured to detect the upward rotation angle of the lifting link 33 using the potentiometer-type lift sensor 76 and calculate the height H of the collector frame 32b from the ground G (Figure 3) (height detection means). Alternatively, an angle sensor 75S may be provided at the base of the lift lever 75 to detect the operating angle of the lift lever 75 and calculate the height H due to the rise of the collector 32. The height H detected by the height detection means is stored in a storage means 78 connected to the motor control device 50.

[0043] As shown in Figures 1 and 3, the rear camera 71 is installed at the rear end of the collector frame 32b. When the collector 32 is lowered, it functions as a normal rear camera as described above, but when the collector 32 rises, the rear camera 71 rises along with the collector frame 32b. In conjunction with the rise of the collector 32, the left half of the liquid crystal display unit 61 switches to an image taken from a higher position. The display then changes from the estimated travel trajectory Y to the grass discharge area Z (Figure 8(B)). This discharge area Z is an estimated representation of the grass fall area when a dump operation is performed between the position of the traveling vehicle 1 and the height H of the collector 32. In this way, by providing the rear camera 71 on the rising and lowering frame, the operator can safely drive by checking the rear of the traveling vehicle 1 when it is lowered, and can easily perform the discharge work by checking the grass discharge area from the collector 32 when it is raised.

[0044] In this case, the right half also switches to display the collector 32 lifting / lowering setting screen. When the collector 32 is raised to a predetermined height, tapping the "Save Collector Height" display stores this collector height H in the control unit. To adjust the collector height H, the user taps the "Up" or "Down" switch 79 for one-touch lifting / lowering. One-touch operation on the "Up" side of the one-touch operation means 79U raises the collector to the stored height H, and one-touch operation on the "Down" side of the one-touch operation means 79D lowers the collector to the storage position. By long-pressing the tap on the "Up" or "Down" display, the collector can continue to rise to a predetermined position or continue to descend to the storage position. Thus, since the stored height H is based on the operator's intention, work efficiency is improved.

[0045] Next, an example of collector 32 lifting and lowering control is shown based on Figure 9. When the collector 32 becomes full during lawn mowing, the work vehicle 1 moves toward the waiting truck T (S101-S104). Then, when it is determined that the discharge area Z is appropriate, the vehicle 1 stops (S105, S106). The lift lever 75 is raised to stop the collector 32 at the desired height, and then the dump cylinder 34C is extended using the dump lever 77 to discharge the grass (S107-S110). Once the grass discharge is complete, the dump lever 77 is returned to its original position and the dump cylinder 34C is shortened and returned to its original position, and the collector 32 returns to a nearly horizontal position (S111, S112). Then, the detected value from the lift sensor 76 is input and the collector height H is calculated, and this detected value and the calculated height H are stored (S113, S114). Subsequently, the lift lever 75 is lowered to return the collector 32 to its designated position (S115). A decision is made as to whether to continue the work, and the above procedure is repeated or the work is stopped (S116, S117).

[0046] When repeating the operation, in S107, as described above, the LCD display 61 is switched to the collector lifting display, and by tapping the "One-touch lifting / raising" display, the collector 32 can be raised all at once to the height H stored in the previous operation in S114. In environments where working conditions such as grass type and humidity do not change, when discharging from the collector 32 to a waiting truck bed T or other predetermined location, the collector 32 can be raised to the set height, improving work efficiency.

[0047] In the embodiment shown in Figure 9, the height H was calculated using the value detected by the lift sensor 76 after the grass was discharged from the collector 32. However, it is also possible to configure the system to detect the grass when the collector 32 is full (as described in S108 and S109) using the lift sensor 76. In this case, the grass load on the collector may affect the detection, but it is more in line with actual work and less likely to cause discrepancies in the discharge position.

[0048] Next, Figure 10 will be explained. In lawn mowing operations, where load fluctuations are large, using a general-purpose controller may not provide sufficient input / output to absorb load fluctuations or allow for the use of a torque map that provides optimal energy efficiency. Furthermore, if multiple motors are driven by a single controller, power supply and communication may become unstable. Moreover, there is a possibility that the output of the drive motor may be limited during operation, which is dangerous. Therefore, the configuration is such that the work motor (hereinafter referred to as PTO motor) 25 is controlled using a PTO motor controller 80 dedicated to the PTO motor 25. In Figure 10, the control unit (VCU) 81 corresponds to the motor control ECU 50 in Figure 6, and the PTO motor controller 80 corresponds to the motor control unit 13 in Figure 6.

[0049] The control unit (VCU) 81 receives signals from the PTO switch 82, PTO rotation speed dial 83, seat sensor 84, mower safety switch 85, blower safety switch 86, PTO mode switching means 87, collector lift sensor 88, collector dump sensor 89, and power range switching switch 90. The control unit (VCU) 81 and the PTO motor controller 80 are configured to send and receive indicated rotation speed signals, actual rotation speed signals, current and voltage signals, temperature signals, etc. The PTO motor controller 80 outputs drive signals to the PTO motor 25 and hydraulic pump 91. The control unit (VCU) 81 outputs proportional signals to the mower clutch 92 and blower clutch 93, and outputs to the swing motor relay 94. The PTO motor controller 80 uses a speed control method, enabling motor control at the optimal rotation speed for mowing and ensuring lawn mowing performance.

[0050] As described above, by controlling the PTO motor 25 using a dedicated PTO motor controller 80 for the PTO motor 25, the functionality of the electric mower can be maximized in lawn mowing operations with large load fluctuations by using a dedicated motor controller 80 tailored to the requirements. Furthermore, by differentiating the control cycle from other motor controllers, an optimal control cycle can be set only for the PTO motor control, enabling highly responsive and accurate motor control. In addition, the load on the motor controllers of the PTO motor 25 and other motors is distributed, suppressing temperature rise, thus extending the working time under high load. Moreover, since the temperature information of the motor controller 80 can be independently fed back, the factors causing the temperature rise of the motor controller 80 can be identified, enabling motor control according to the usage conditions.

[0051] Furthermore, since the input / output between the PTO motor 25 and the PTO motor controller 80, and between the PTO motor controller 80 and the control unit (VCU) 81 can be performed independently of the drive motor, responsiveness can be ensured, leading to improved lawn mowing quality through high-precision motor control. For example, the current and voltage can be controlled according to the working load of the PTO motor 25, enabling power supply with minimal loss during lawn mowing operations with large load fluctuations. In addition, the output torque can be stabilized, improving the work quality of the PTO motor 25.

[0052] Since the target motor rotation speed cannot be determined without determining the optimal rotation speed of the cutting blade for lawn mowing, the cutting blade 4 is designed to function at the appropriate rotation speed.

[0053] Furthermore, a resolver (not shown) is used instead of a Hall IC or encoder for detecting the rotational speed or rotational angle of the PTO motor 25. When detecting the rotational angle using a Hall IC, the PTO motor controller 80 may become hot during high-load lawn mowing operations, causing the rotational angle to be misdetected due to the effects of temperature changes. On the other hand, when detecting the rotational angle using an encoder, vibrations and shocks during lawn mowing operations may also cause the rotational angle to be misdetected, and in either case, the required rotational speed may not be output. However, by using a resolver, the effects of high temperatures, vibrations, and shocks during lawn mowing operations are less likely to occur, ensuring reliable rotational angle detection and enabling motor control that maintains the required rotational speed. Moreover, since the resolver does not have optical or electronic components built inside, it is relatively resistant to noise, enabling rotational angle detection even in the high-voltage, high-load environment of electric lawnmowers.

[0054] During high-load operations, there is a risk of component damage due to exceeding the component's rating in an attempt to maintain rotational speed. Therefore, the PTO motor controller 80 should be configured to limit output by maximum torque. This ensures optimal mowing performance by maintaining the cutting blade rotational speed while protecting the components. In this case, by configuring the limit to be set by the maximum torque determined based on the durability performance of the cutting blade, it is possible to protect the cutting blade while maintaining a rotational speed suitable for lawn mowing. Furthermore, by setting the maximum torque so as not to exceed the battery's output rating, it is possible to protect the battery while maintaining a rotational speed suitable for lawn mowing. In addition, by configuring the output limit to be set by the maximum torque determined based on the durability performance of the gear, it is possible to protect the gear while maintaining a rotational speed suitable for lawn mowing.

[0055] As described above, in Figure 10, the PTO motor 25 is controlled using a dedicated PTO motor controller 80, and the motor controller 80 is instructed to control the rotation speed of the PTO motor 25. Therefore, an arbitrary rotation speed can be set for the PTO motor 25 independently of the drive motor, making it possible to set a rotation speed suitable for various lawn mowing operations, such as when power steering is driven or when the collector cylinder or dump cylinder is extended or retracted.

[0056] The system is equipped with a dial sensor that corresponds to the operation of the PTO speed dial 83 for determining the rotational speed of the PTO motor 25. When the clutches 92 and 93 of the mower or blower are engaged, the rotational speed of the PTO motor 25 is continuously variable using the analog input of the dial sensor. This configuration allows the operator to arbitrarily set the PTO motor 25 rotational speed appropriate for the task.

[0057] Furthermore, it is advisable to set the minimum and maximum rotational speeds of the PTO motor 25 here, and configure the system so that the rotational speed between these two values ​​can be varied by a dial sensor. This allows for maximizing the motor's performance while ensuring the minimum required rotational speed of the PTO motor 25. Additionally, the analog input of the dial sensor for the PTO rotational speed dial 83 should be kept constant near the minimum and maximum rotational speeds. Even if there are individual differences in the dial sensors, a constant minimum and maximum rotational speed can be achieved as long as the difference is within a certain range.

[0058] Incidentally, when the PTO speed dial 83 is near its minimum value, if 0 rpm is indicated, depending on the position of the PTO speed dial 83, it may not be possible to secure the necessary hydraulic pressure from the hydraulic pump 91, which is required for other controls such as power steering. Also, when the analog input value of the dial sensor becomes near 0 bits due to a wire break, it may not be possible to secure the necessary hydraulic pressure. Therefore, by configuring the PTO speed dial 83 so that the minimum rotation speed can be indicated when the analog input of the dial sensor is near its minimum value, it is possible to secure the necessary hydraulic pressure for power steering, etc., regardless of the position of the PTO speed dial 83 or when the dial sensor is broken.

[0059] Furthermore, when both the moor clutch 92 and the blower clutch 93 are disengaged, and both the collector lift sensor 88 and the collector dump sensor 89 are OFF, i.e., when the unit is in a shortened state and neither the collector cylinder nor the dump cylinder is used, the PTO motor 25 is configured to instruct a minimum rotation speed. This reduces power consumption by using the minimum necessary hydraulic pressure according to the operation, which in turn extends the operating time. When both the moor clutch 92 and the blower clutch 93 are disengaged, and either the collector lift sensor or the collector dump sensor is ON, i.e., when the unit is in an extended state and both the collector cylinder and the dump cylinder are used, the PTO motor 25 is configured to instruct a rotation speed corresponding to the dial sensor output. This ensures that the necessary hydraulic pressure is secured only during operation, reducing power consumption while fulfilling the function. Furthermore, when both the moor clutch 92 and the blower clutch 93 are disengaged, the PTO motor 25 is configured to instruct a rotation speed corresponding to the dial sensor output. This means that while changing the PTO motor rotation speed in response to operation can sometimes make it difficult for the operator to operate the system because it takes time to build up the necessary hydraulic pressure, the time required for hydraulic operation is shortened, leading to improved operability. [Explanation of Symbols]

[0060] 1. Running vehicle 4 cutting blade 5 Moa 32 collector 54 Collector lifting operation unit 60 Display Panels 71 Rearview camera 74 Collector lifting operation unit (one-touch lifting mechanism) 75 Lift Lever 76 Height detection means 78 Memory means 79U Collector Lifting Operation Unit (One-Touch Lifting Mechanism) 79D Collector Lifting Operation Unit (One-Touch Lifting Mechanism)

Claims

1. A riding lawnmower is provided with a mower (5) having a cutting blade (4) on a traveling vehicle body (1), and a collector (32) for collecting cut grass is configured to be able to be raised and lowered and to be able to be dumped, characterized in that it is provided with a height detection means (76) for detecting the height to which the collector (32) has been raised and a storage means (78) for storing the detected height (H), and when the collector raising and lowering operation unit (54, 74, 79U) is operated, the collector (32) is raised to the stored position.

2. The riding lawnmower according to claim 1, wherein the height detection means (76) is configured to detect the collector height (H) when the dump operation is performed.

3. The riding lawnmower according to claim 1, wherein the height detection means (76) is configured to output a collector height (H) arbitrarily set by the operator.

4. The riding lawnmower according to claim 1, wherein a rear camera (71) is provided at the rear of the traveling vehicle body (1) at a position that moves up and down with the raising and lowering of the collector (32), the camera image is displayed on a display panel (60), and the grass discharge area (Z) is displayed on the imaging screen (72) of the rear camera (71) when the collector (32) is raised.

5. The riding lawnmower according to claim 1, further comprising a lift lever (75) that controls the raising and lowering of the collector (32), and a one-touch operating means (79U) that raises the collector to a height (H) stored in a memory means (78).

6. The riding lawnmower according to claim 5, further comprising a one-touch operating means (79D) for lowering the collector (32) back to its storage position.

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