Riding lawnmower

Abstract

The objective is to provide a riding lawnmower that allows for easy collection of discharged grass by reversing the radiator fan. [Solution] In a riding lawnmower equipped with a radiator 43 and a radiator fan 44 mounted on one side of the vehicle body 1, and having a fan forward / reverse mode in which the radiator fan 44 rotates in a forward state that draws in outside air and a reverse state that is the opposite when the engine 11 is running, the radiator fan 44 located on one side of the vehicle body 1 is configured to execute the fan forward / reverse mode when it is facing an unworked area, and to always rotate in the forward direction without executing the fan forward / reverse mode when it is facing an already-worked area.

Description

Technical Field

[0001] The present invention relates to a riding lawn mower equipped with a lawn mowing device for performing lawn mowing work, and particularly relates to a structure for preventing the deposition of dust such as mowed grass around the engine.

Background Art

[0002] There is a known riding lawn mower that includes a radiator and a radiator fan, and by reversing the radiator fan at regular intervals, the dust clogged in the dust cover can be blown outwards (Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] According to the invention described in Patent Document 1 above, it is possible to remove the grass stuck to the filter by reversing the radiator fan, but there has been a case where the discharged grass is discharged to the already-worked area where the work has been performed.

[0005] An object of this invention is to provide a riding lawn mower that can easily collect the discharged grass by reversing the radiator fan.

Means for Solving the Problems

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

[0007] The invention described in claim 1 is a riding lawnmower equipped with a radiator 43 and a radiator fan 44 mounted on one side of the vehicle body 1, and having a fan forward / reverse mode in which the radiator fan 44 performs a forward rotation state in which outside air is drawn in and a reverse rotation state in which the opposite state is performed while the engine 11 is operating, wherein the radiator fan 44 located on one side of the vehicle body 1 is configured to perform the fan forward / reverse mode when it is facing an unworked area, and to always rotate in the forward direction without performing the fan forward / reverse mode when it is facing an already worked area.

[0008] The invention described in claim 2 is the invention described in claim 1, wherein a positioning device 60 is provided on the vehicle body 1, the controller C is configured to perform driving and turning control along a straight path 62 and a turning path 63 while confirming the vehicle body 1's own position, and the controller C is configured to determine whether the radiator fan 44 is facing an unworked area or a completed work area, and to execute or not execute the fan forward / reverse mode.

[0009] The invention described in claim 3 is the invention described in claim 1 or claim 2, further comprising a steering angle sensor 67 for detecting the steering angle of the rear wheel 3 as a turning steering wheel, and configured to perform a reverse rotation of the radiator fan 44 within a predetermined time or before moving a predetermined distance when transitioning from the turning path 63 to the straight path 62 based on the detection by the steering angle sensor 67. [Effects of the Invention]

[0010] According to the invention described in claims 1 and 2, during operation, it is determined whether the radiator fan 44 is facing an unworked area or an already-worked area, and the fan forward / reverse mode is executed. When the radiator fan 44 is facing an already-worked area, the radiator fan 44 rotates only in the forward direction. When the radiator fan 44 is facing an unworked area, the radiator fan 44 reverses to a predetermined direction to blow dust and grass into this unworked area, preventing clogging of the dust cover 50. The blown-away dust and grass are collected together with the grass that is cut in the unworked area.

[0011] According to the invention described in claim 3, in addition to the effects described in claim 1 or claim 2, the radiator fan 44 can be reversely rotated before the temperature of the radiator 43 rises by reversely rotating it within a predetermined time.

Brief Description of the Drawings

[0012] [Figure 1] It is a side view of a riding lawn mower according to an embodiment of the present invention. [Figure 2] It is a left rear oblique perspective view of a riding lawn mower with the collector removed. [Figure 3] It is a right rear oblique perspective view of the riding lawn mower in FIG. 2 with the bumper removed. [Figure 4] It is a rear view of a riding lawn mower. [Figure 5] It is a plan view of the vehicle body. [Figure 6] It is a perspective view of the radiator and its vicinity. [Figure 7] It is a control block diagram. [Figure 8] It is a flowchart. [Figure 9] (A) and (B) are schematic diagrams showing an example of a lawn mowing operation route. [Figure 10] It is a side view of another example of a riding lawn mower. [Figure 11] It is a plan view of another example of the vehicle body. [Figure 12] (A) is a perspective view of a lawn mowing device, and (B) is a schematic diagram of the transmission of a working motor. [Figure 13] It is a schematic diagram of the transmission of a front and rear wheel drive motor. [Figure 14] It is a perspective view of another example vehicle body with the collector and cover members removed. [Figure 15] (A), (B), (C), and (D) are side views showing the outline of the arrangement of an electric motor and a radiator - cooling fan.

Modes for Carrying Out the Invention

[0013] Hereinafter, embodiments of the present invention will be described in detail based on the drawings.

[0014] A side view of the riding lawn mower 1 of this embodiment is shown in FIG. 1.

[0015] The front part and the rear part of the traveling vehicle body 1 are respectively provided with front wheels 2, 2 and rear wheels 3, 3. Below the front part of the vehicle body 1 and in front of the front wheels 2, 2, a lawn mowing device 5 for mowing grass having a cutting blade 4 is provided, constituting a so-called front mower. On the floor 6 part above the front part of the vehicle body 1, a steering column 7 is erected, and a steering handle 8 is provided on the upper part of the column 7. Also, a driver's seat 9 is provided behind the handle 8.

[0016] Regarding the frame structure of the vehicle body 1 in detail, from the front side, there are a floor frame 10 that supports the floor 6, the driver's seat 9, etc., a transmission case 12 that houses a transmission system that receives the power of the engine 11 and drives a traveling transmission device (for example, HST) and a lawn mowing device 5, a safety guard frame 13 fixed to the upper part of the transmission case 12, and a pair of left and right side frames 14L, 14R that are connected to the lower end of the transmission case 12 and support the engine 11, etc.

[0017] The floor frame 10 is formed in a U shape in plan view on the front side, supports the column 7 at the front part, and is provided at the rear part to support the driver's seat 9 and an operation box for various levers, etc. The left and right rear ends are connected to the left and right side surfaces 13L, 13R of the safety guard frame 13 in a superimposed state. The left and right side surfaces 13L, 13R of the safety guard frame 13 are configured to connect the left and right support column parts 15L, 15R of the safety guard 15, and the upper ends of these left and right support column parts 15L, 15R are connected by a head frame 15H. L-shaped case connection parts 13aL, 13aR are provided on the lower left and right sides of the safety guard frame 13, and each is fixedly connected to the upper surface and the rear surface of the transmission case 12 to obtain a strong rigid structure.

[0018] The transmission case 12 is a part that constitutes the frame structure of the vehicle body 1 as described above, and traveling transmission cases 12aL, 12aR that house transmission endless belts and gears to the front wheels 2, 2 are mounted on the left and right ends of the transmission case 12 in a transmissible manner.

[0019] The left and right side frames 14L and 14R are connected and fixed to the lower part of the transmission case 12. The side frames 14L and 14R extend to the rear, and an engine mounting base plate 14E is formed in the middle of the front and rear sections, providing vibration-damping support for the engine 11. A rear axle case 16 is provided above the rear ends of the side frames 14L and 14R. The rear axle case 16 houses the rear wheel differential mechanism, left and right axles, reduction gear mechanism, etc. The rear ends of the side frames 14L and 14R are connected and fixed to each other by left and right connecting members 14S.

[0020] An upper frame 17 is positioned slightly higher than the height of the engine 11. The upper frame 17 is shaped like a U in plan view, with the curved portion facing rear and its left and right front ends connected to nearby frames. More specifically, the front ends are connected and fixed to a horizontal frame 19 that connects a pair of left and right vertical frames 18L and 18R, whose lower ends are fixed to the safety guard frame 13 and which are erected vertically.

[0021] Next, the rear section of the frame structure of the vehicle body 1 will be described. Two reinforcing vertical supports 20L and 20R are provided between the rear ends of the left and right side frames 14L and 14R and the upper frame 17. By fixing an appropriate number of horizontal bars 20H and 20H between the upper and lower sections of these vertical supports 20L and 20R, a ladder-like reinforcement is achieved.

[0022] A bumper 21 is attached to a horizontal bar 20H positioned slightly higher than the vertical center of the aforementioned vertical supports 20L and 20R. An air cleaner 31 is also positioned on the inside of the rear of the vehicle body 1.

[0023] As shown in Figure 1, a collector 32 for collecting cut grass is provided behind the safety guard 15 and above the upper frame 17 via a lifting mechanism. The lifting mechanism comprises a parallel link lifting arm 33 and a lifting cylinder mechanism 34. One end is connected to the safety guard frames 13L and 13R that support the safety guard 15, and the other end is connected to a collector frame 35 on which the collector 32 can be mounted. The cut grass from the lawn mowing device 5 is blown by a blower (not shown) and collected in the collector 32 via a bellows hose 36 and a duct 37. The duct 37 faces the receiving inlet of the collector 32, and is configured so that the outlet of the duct 37 and the receiving inlet of the collector 32 coincide when the collector 32 is lowered, and the duct 37 can easily separate from the receiving inlet of the collector 32 when the collector 32 is raised, so as not to interfere with the lifting operation of the collector 32.

[0024] A rear cover 41 is provided on the rear side of the vehicle body 1 so as to cover the area above the central sheet metal material 22 of the bumper 21. A battery case 42 for housing the battery is located on the left side of the vehicle body 1, and a radiator 43 is located on the right side of the vehicle body 1.

[0025] Next, the radiator 43 and its surrounding structure will be described based on Figure 6. The radiator 43 and radiator fan 44 are installed on the front side of the engine 11, which has a crankshaft (not shown) positioned in the front-rear direction of the vehicle body 1, on the side of the vehicle body 1 (right side in the illustrated example), with the fan shaft 45 axis perpendicular to the crankshaft. The bracket 46 supporting the radiator 43 body is formed in a U shape to surround the left and right sides (front and rear sides relative to the vehicle body 1) and the bottom, and is rigidly constructed with an upper bracket 47 that connects the left and right bracket sections 46L and 46R at the top. The brackets 46 of the left and right bracket sections 46L and 46R and the bottom bracket section 46B are directly or indirectly connected to the side frame 14R and the upper frame 17 to support the radiator 43. The shroud 44a of the radiator fan 44 is attached to the bracket 46, and a reversible electric motor 48 is connected to the fan shaft 45. This electric motor 48 is fixed by a support arm 49 that protrudes from the radiator body 43.

[0026] Outside the radiator 43, a dust cover 50 is positioned, which is made of perforated metal or mesh formed into a box shape with small holes, using the bracket 46 and upper bracket 47 as a base. The radiator fan 44 also rotates forward as the electric motor 48 rotates, drawing in outside air. The outside air passes through the dust cover 50 and the radiator 43 before being introduced into the engine 11 inside the vehicle body 1.

[0027] Since the electric motor 48 is provided to be reversible, the radiator fan 44 can be reversed to blow away dust accumulated in the dust cover 50. The reversal time tr is set to be very short so that even if the intake of outside air by the radiator fan 44 is interrupted, there will be no problem with the cooling of the radiator water. The reversal of the radiator fan 44 is set to be repeated at predetermined intervals after the engine 11 is started, as shown in the flowchart in Figure 8, for example. The controller C receives operation signals from various switches and levers, detection signals from sensors, and is also configured to periodically receive detection signals from a water temperature sensor 55 that detects the radiator water temperature (Figure 7). In Figure 8, when the engine 11 of the riding lawnmower is started, the electric motor 48 starts to rotate forward and the radiator fan 44 rotates forward (S101, S102). Next, it is determined whether the fan forward / reverse mode is selected. If this fan forward / reverse mode is selected by turning on the mode setting switch (not shown) or the like (S103), the controller C starts counting a preset forward rotation time ts (e.g., 15 minutes) (S104). After the forward rotation time ts has elapsed (S105), the controller C compares the detected coolant temperature T by the water temperature sensor 55 with a preset set water temperature T1 (e.g., 95°C). If the detected coolant temperature T > set water temperature T1 (S106), the radiator fan 44 is controlled to stop (S107). The controller C outputs a reverse switching signal to the electric motor 48, and the radiator fan 44 also reverses (S108). The controller C starts counting a preset reverse rotation time tr (e.g., 2 seconds) (S109). After the forward rotation time ts has elapsed, the controller C outputs a stop signal to the electric motor 48, and the radiator fan stops (S111). Subsequently, the radiator fan 44 repeatedly rotates forward for ts time and reverses for tr time (S113). By reversing the radiator fan 44 at regular intervals in this way, dust accumulated in the dust cover 50 can be blown outwards. The aforementioned reversal time tr is set to be very short so as not to interfere with radiator water cooling.

[0028] The example of selecting the fan forward / reverse mode from the flowchart described above will now be explained. First, there is the setting using the mode selection switch 56. If the operator determines that it is necessary to reverse the radiator fan 44 before starting work, they can turn on this mode selection switch 56 to reverse the radiator fan 44 to a predetermined position, thereby blowing away and removing the dust accumulated in the dust cover 50.

[0029] Incidentally, as mentioned above, if the radiator 43 and radiator fan 44 are installed on one side of the vehicle body 1 (the right side in the illustrated example), the dust from the dust cover 50 will be blown to the ground when the radiator fan 44 is reversed. In particular, if the dust is discharged after mowing the grass, it will accumulate in the neatly mowed area, requiring further collection work and spoiling the aesthetics.

[0030] Therefore, the radiator fan 44 is located on one side of the vehicle body 1 (the right side in the illustrated example) and is configured to execute a fan forward / reverse mode when it is facing (desired to be facing) an unworked area, and not to execute a fan forward / reverse mode when it is facing (desired to be facing) an already-worked area. For this purpose, a fan position determination means is configured to determine whether the radiator fan 44 is facing an unworked area or an already-worked area during operation, and by executing the fan forward / reverse mode based on the determination result of this fan position determination means, when the radiator fan 44 is facing an already-worked area, the radiator fan 44 will only rotate in the forward direction, and when the radiator fan 44 is facing an unworked area, the radiator fan 44 will reverse to a predetermined direction to blow dust and grass into this unworked area to prevent clogging of the dust cover 50, and the blown-away dust and grass will be collected together with the grass that is cut in the unworked area.

[0031] Furthermore, the vehicle body 1 is equipped with a GPS device 60 as an example of a positioning device. The GPS device 60 can determine its own position by communicating with GPS satellites 61. In addition, the controller C of the vehicle body 1 transmits and receives information with the server S via a communication means, transmitting information about the location of the vehicle body 1 and information about the state of stopped driving, and receives instruction signals for the work area and work route within a predetermined work range from the server S. Therefore, work can be performed along the reciprocating lawn mowing work route shown in Figure 9. By inputting or storing the placement positions of the radiator 43 and radiator fan 44 on the vehicle body 1 in advance, it is possible to determine whether the radiator fan 44 of the vehicle body 1 is facing an unworked area or an already-worked area based on the placement position information and work route information. Therefore, when performing work along the reciprocating lawn mowing work route shown in Figure 9, it is possible to determine whether the radiator fan 44 is facing an unworked area or an already-worked area, and at the same time, it is possible to determine whether or not to execute the fan forward / reverse mode.

[0032] In Figure 9, the server S calculates and processes a straight path 62 and a turning path 63 for mowing a predetermined rectangular work area A, and transmits them to the controller C of the vehicle body 1. The controller C is configured to control the vehicle body 1's movement and turning so that it follows the straight path 62 and the turning path 63 while confirming its own position. When the vehicle body 1 is in Figure 9(A), the radiator 43 and radiator fan 44 located on the right side of the vehicle body 1 face the already worked area (the area shown by hatching in Figure 9) 64, so the execution of the fan forward / reverse mode is restricted. When the vehicle body 1 is in Figure 9(B), the right side of the vehicle body 1 faces the unworked area 65, so the fan forward / reverse mode is executed.

[0033] As shown in Figure 9(B), when the fan forward / reverse mode is executed, the vehicle body 1 is equipped with a work load sensor 66, and the controller C is configured to make a decision to prompt the execution of the fan forward / reverse mode within a predetermined time after detecting that the work load is above a predetermined value after transitioning from the turning path 63 to the next straight path 62. With this configuration, by reversing within a predetermined time, the radiator fan 44 can be reversed before the radiator 43 temperature rises. Furthermore, if the right side of the vehicle body 1 faces the already completed work area and the execution of the fan forward / reverse mode is refused, the timing of the radiator fan 44 reversal in the next straight path 62 can be applied.

[0034] Furthermore, the vehicle body 1 is equipped with a steering angle sensor 67 that detects the steering angle of the rear wheels 3, which act as steering wheels. Based on the detection by the steering angle sensor 67, it is determined that the vehicle has transitioned from a turning path 63 to a straight path 62, and the radiator fan 44 is reversed within a predetermined time or before moving a predetermined distance, thereby avoiding the radiator fan 44 reversing when the radiator water temperature 43 is high.

[0035] In Figure 5, the engine 11 receives power and transmits it to the HST 51, which acts as a drive transmission. The output rotation of the HST 51 can be changed to high or low by controlling the rotation of the trunnion shaft (not shown). The power of the HST 51 is transmitted to the front wheels 2,2 and the rear wheels 3,3, enabling the vehicle body 1 to be driven. A cooling fan 52 is positioned between the HST 51 and the engine 11, rotating due to the driving force of the engine 11 and providing air cooling for the engine 11. The radiator 43 is positioned to the side of this cooling fan 52.

[0036] The engine 11 is located behind an exhaust gas retreatment device 53 connected to the exhaust manifold. The exhaust gas retreatment device 53 in the illustrated example has a known configuration in which a filter (DPF) that filters out and reduces particulate matter (PM) in the exhaust gas of the diesel engine is installed in the exhaust passage, and the purified exhaust gas is discharged outside the vehicle body 1 through the tailpipe 54.

[0037] Next, we will describe the motor cooling means for a lawnmower that uses electric motors as the drive motor and the motor for the work equipment.

[0038] As shown in Figures 10 to 12, gear cases 121L and 121R are provided on the upper left and right sides of the mower deck 120 of the lawn mowing device (mower) 105, and the left and right cutting blade shafts 123L and 123R, each mounted with a cutting blade 104 for cutting grass, are vertically supported in these gear cases. The transmission mechanisms inside these left and right gear cases 121L and 121R are connected by a transmission shaft 124, and the left and right cutting blade shafts 123L and 123R are driven by a work motor 125, which will be described later and is linked to the transmission mechanism inside the left gear case 121L.

[0039] The driving force of the work motor 125 is transmitted to the left cutting blade shaft 123L, which is pivotally supported vertically downward in the left gear case 121L, and further transmitted from the left gear case 121L via the transmission shaft 124 to the right cutting blade shaft 123R, which is pivotally supported vertically downward in the right gear case 121R, thereby driving it.

[0040] Side frames 114L and 114R are attached to the vehicle body 101, a battery 112 is placed on top of them, and a motor control unit 113 housed in a casing is mounted on top of that. Electrodes for the motor are provided on the top surface of the battery 112 and covered by the motor control unit 113, with the cords extending from the side of the motor control unit 113 and routed through it. The cords from the battery 112 and the motor control unit 113 to the work motor 125 are routed along the outer surface of the chute 136.

[0041] Figure 13 shows the power transmission system for the left and right front wheels 102L, 102R and rear wheels 103L, 103R, which serve as drive wheels. Power is transmitted from the front wheel drive motor 140, which is a driving motor with its output shaft facing forward, to the left and right front wheels 102L, 102R via the front differential mechanism 141 and left and right reduction mechanisms 142L, 142R. Power is transmitted from the rear wheel drive motor 143, which is a driving motor with its output shaft facing rear, to the left and right rear wheels 103L, 103R via the rear differential mechanism 144 and left and right reduction mechanisms 145L, 145R. The rotation of the front wheel drive motor 140 is detected by the front axle rotation sensor 146F, and the rotation of the rear wheel drive motor 143 is detected by the rear axle rotation sensor 146R.

[0042] In the above embodiment, a three-motor configuration was used, consisting of a work motor 125, a front-wheel drive motor 140, and a rear-wheel drive motor 143. However, by configuring power transmission means to each part as shown in the engine 11 in Figure 5, it is also possible to use a single electric motor 150. The position of this single electric motor 150 can be designed as appropriate, but in the illustrated example, it is positioned near the location of the front-wheel drive motor 140 (Figure 14).

[0043] Furthermore, a radiator 151 and a cooling fan 152 are provided to cool the electric motor 150. For example, the radiator 151 and cooling fan 152 may be placed above the electric motor 150 (Figure 15(A)) or below the electric motor 150 (Figure 15(B)). With this configuration, efficient cooling is possible using cooling air from the upper or lower part of the vehicle body and the airflow while driving. In addition, by integrating the radiator 151 and the cooling fan 152, the head of the cooling water is reduced, and the load on the water pump (not shown) is reduced.

[0044] Furthermore, it can also be positioned on the side of the electric motor 150 (Figure 15(C)). This allows for the same arrangement as the radiator 43 and radiator fan 44 configuration of the engine 11 specification shown in Figure 1, improving commonality and reducing costs. It can also be positioned between the electric motor 150 and the seat 109 (rear of the fender) (Figure 15(D)). This allows for air cooling of the electric motor 150 and removal of hot air and dust around the seat 109.

[0045] Incidentally, the electric motor 150 can also be composed of a work motor and a drive motor, arranged in parallel. In this case as well, the respective effects can be expected based on the arrangements shown in Figures 15(A) to (D). [Explanation of Symbols]

[0046] 1. Vehicle body 3. Rear wheels (steering wheels) 11 Engine 43 Radiator 44 Radiator fan 60 Positioning device 62 Straight Routes 63 Turning Path 67. Steering Angle Sensor C Controller

Claims

1. A riding lawnmower equipped with a radiator (43) and a radiator fan (44) on one side of the vehicle body (1), and having a fan forward / reverse mode that allows the radiator fan (44) to rotate in a forward state that draws in outside air and in a reverse state that is the opposite, while the engine (11) is running, is characterized in that the fan forward / reverse mode is executed when the radiator fan (44) on one side of the vehicle body (1) is facing an unworked area, and when it is facing an already worked area, the fan forward / reverse mode is not executed and the radiator fan (44) always rotates in the forward direction.

2. The riding lawnmower according to claim 1, wherein a positioning device (60) is provided on the vehicle body (1), the controller (C) is configured to perform driving and turning control so as to follow a straight path (62) and a turning path (63) while confirming the vehicle body (1)'s own position, and the controller determines whether the radiator fan (44) is facing an unworked area or a completed work area, and is configured to execute or not execute a fan forward / reverse mode.

3. A riding lawnmower according to claim 1 or claim 2, comprising a steering angle sensor (67) for detecting the steering angle of the turning steering wheel (3), and configured to transition from a turning path (63) to a straight path (62) based on the detection by the steering angle sensor (67) and to reverse the radiator fan (44) within a predetermined time or before moving a predetermined distance.

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