Work vehicle

By positioning the battery and inverter devices separately and optimizing motor shaft orientations, the work vehicle prevents controller malfunctions from electromagnetic noise, improving efficiency and performance.

JP2026003004APending Publication Date: 2026-01-08ISEKI & CO LTD
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Patent Information

Application Number
JP2025179852
Authority / Receiving Office
JP · JP
Patent Type
Applications
Current Assignee / Owner
Filing Date
2025-10-24
Publication Date
2026-01-08

AI Technical Summary

Technical Problem

The controller of a work vehicle is prone to malfunction due to electromagnetic noise generated by the inverter driving the rear wheels and work equipment, as it is located near the steering control unit.

Method used

The work vehicle is designed with a battery in the bonnet section, separate inverter devices for the rear wheels and work implement in an electrical box, and a controller positioned away from the electrical box to prevent interference, along with optimized motor shaft orientations and transmission paths to enhance efficiency and reduce noise impact.

Benefits of technology

The controller is protected from electromagnetic interference, transmission mechanisms are streamlined, and the vehicle operates with improved efficiency and cutting performance, reducing the risk of malfunction and enhancing overall vehicle performance.

✦ Generated by Eureka AI based on patent content.

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Abstract

To provide a working vehicle in which a controller of the working vehicle is prevented from malfunctioning due to noise such as electromagnetic waves generated in an inverter.SOLUTION: The battery (50) is provided in the hood portion (5), the electric component box (70) is provided between the operator's seat (60) and the chute (46), the first inverter device (81) that drives the first electric motor (30) and the second inverter device (82) that drives the second electric motor (40) are provided in the electric component box (70), the controller (77) that controls the electronic devices mounted on the traveling vehicle body (1) is provided at a position separated from the electric component box (70), and the controller (77) is provided in the hood portion (5).SELECTED DRAWING: Figure 25
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Description

[Technical Field]

[0001] The present invention relates to a work vehicle equipped with a work implement that is driven through a park or the like to cut grass or the like planted in the park. [Background technology]

[0002] A known technology involves providing a pair of rear wheel electric motors at the rear of a work vehicle's traveling body to drive the pair of rear wheels, providing a work machine electric motor between the rear wheel electric motors to start the work machine, and providing a battery at the front of the work vehicle's traveling body to store electricity to be supplied to the rear wheel and work machine electric motors (Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-218951 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the method of Patent Document 1, an inverter that drives the electric motors for the rear wheels and the work equipment is located near a controller that performs steering control of the work vehicle, so there is a risk that the controller of the work vehicle may malfunction due to noise such as electromagnetic waves generated by the inverter.

[0005] SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a work vehicle in which the controller of the work vehicle is prevented from malfunctioning due to noise such as electromagnetic waves generated by the inverter. [Means for solving the problem]

[0006] The present invention, which has solved the above problems, is as follows.

[0007] That is, the invention described in claim 1 is a work vehicle having a pair of left and right front wheels (2) at the front of a traveling body (1), a pair of left and right rear wheels (3) at the rear of the traveling body (1), a work implement (4) for cutting weeds between the front wheels (2) and the rear wheels (3) of the traveling body (1), a bonnet section (5) having a predetermined space at the front of the traveling body (1), a control section (6) on which a driver sits at the rear of the bonnet section (5), and a grass collection container (8) for storing weeds cut by the work implement (4) at the rear of the control section (6), A battery (50) is provided in the bonnet section (5), a first electric motor (30) for driving the rear wheels (3) and a second electric motor (40) for driving a work implement (4) are provided in the rear of the traveling vehicle body (1), an electrical box (70) is provided between a driver's seat (60) of the control section (6) and a chute (46) for connecting the discharge opening of the work implement (4) and the discharge opening of the grass collection container (8) in side view, a first inverter device (81) for driving the first electric motor (30) and a second inverter device (82) for driving the second electric motor (40) are provided in the electrical box (70), and a controller (77) for controlling electronic devices mounted on the traveling vehicle body (1) is provided at a position separated from the electrical box (70). The controller (77) is provided in the bonnet (5). This is a work vehicle characterized by the above.

[0008] The invention described in claim 2 is 2. The work vehicle according to claim 1, wherein a first output shaft (30A) of the first electric motor (30) is provided along a left-right direction, and a second output shaft (40A) of the second electric motor (40) is provided along a front-rear direction. is.

[0009] The invention described in claim 3 is 3. The work vehicle according to claim 2, wherein a gear box (31) for reducing the output rotation speed of the first output shaft (30A) and switching the rotation direction is provided on one side of the first electric motor (30), the rear wheels (3) and the gear box (31) are connected by a drive shaft (33) extending in the left-right direction, and the first electric motor (30) is provided above the second electric motor (40) and the second output shaft (40A) is provided above the drive shaft (33) in rear view. is.

[0010] The invention described in claim 4 is 4. The work vehicle according to claim 2 or 3, wherein, in rear view, the first electric motor (30) and the second electric motor (40) are provided offset to one side in the left-right direction, and the chute (46) and the grass collection container (8) are provided on the other side in the left-right direction. is. [Effects of the Invention]

[0011] According to the invention described in claim 1, a battery (50) is provided in the bonnet section (5), a first electric motor (30) for driving the rear wheels (3) and a second electric motor (40) for driving the work implement (4) are provided in the rear of the traveling body (1), an electrical box (70) is provided between the driver's seat (60) of the control section (6) and the chute (46) connecting the discharge outlet of the work implement (4) and the discharge inlet of the grass collection container (8) in a side view, a first inverter device (81) for driving the first electric motor (30) and a second inverter device (82) for driving the second electric motor (40) are provided in the electrical box (70), and a controller (77) for controlling the electronic devices mounted on the traveling body (1) is provided at a position separated from the electrical box (70), thereby preventing the controller (77) from malfunctioning due to noise such as electromagnetic waves generated by the first inverter device (81) and the second inverter device (82). Furthermore, since the controller (77) is provided inside the bonnet (5), it is possible to further prevent the controller (77) from malfunctioning.

[0012] According to the invention of claim 2, in addition to the effects of the invention of claim 1, Since the first output shaft (30A) of the first electric motor (30) is provided along the left-right direction and the second output shaft (40A) of the second electric motor (40) is provided along the front-rear direction, it is possible to reduce the number of parts in the transmission mechanism between the first electric motor (30) and the rear wheels (3) and the transmission mechanism between the second electric motor (40) and the work machine (4).

[0013] According to the invention of claim 3, in addition to the effects of the invention of claim 2, A gearbox (31) that reduces the speed of the output rotation of the first output shaft (30A) and switches the direction of rotation is provided on one side of the first electric motor (30), and the rear wheels (3) and the gearbox (31) are connected by a drive shaft (33) that extends in the left-right direction. When viewed from behind, the first electric motor (30) is provided above the second electric motor (40), and the second output shaft (40A) is provided above the drive shaft (33). As a result, the lengths of the transmission path between the first electric motor (30) and the rear wheels (3) and the transmission path between the second electric motor (40) and the work machine (4) can be shortened, thereby improving transmission efficiency.

[0014] According to the invention of claim 4, in addition to the effects of the invention of claim 2 or 3, When viewed from the rear, the first electric motor (30) and the second electric motor (40) are offset to one side in the left-right direction, and the chute (46) and the grass collection container (8) are provided on the other side in the left-right direction, so that a large chute (46) and grass collection container (8) can be provided on the opposite side of the first electric motor (30) and the second electric motor (40), thereby improving cutting efficiency. [Brief explanation of the drawings]

[0015] [Figure 1] FIG. [Figure 2] FIG. 2 is a left side view of the work vehicle with the bonnet cover in an open position. [Figure 3] FIG. 2 is a perspective view of a main part of a work vehicle with a part cut away. [Figure 4] FIG. [Figure 5] FIG. 2 is a plan view of the rear wheels and the main parts of the work machine. [Figure 6] FIG. 2 is a left side view of the rear wheel and the main part of the work machine. [Figure 7] FIG. 2 is a left side view of the electric motor for the rear wheels and the electric motor for the work machine. [Figure 8] FIG. 2 is a perspective view of a speed change lever for increasing or decreasing the rotation speed of the cutting blade of the work machine. [Figure 9] FIG. [Figure 10] FIG. [Figure 11] FIG. 2 is a perspective view of the battery and the steering post. [Figure 12] FIG. 2 is a plan view of the work vehicle excluding the hood cover and the driver's seat. [Figure 13] FIG. 2 is a perspective view of a battery and a battery bracket. [Figure 14] FIG. [Figure 15] FIG. 2 is a front view of the front wheel, the battery, and the battery bracket. [Figure 16] FIG. [Figure 17] FIG. 2 is an explanatory diagram of a protected space formed by a protective frame and a safety frame. [Figure 18] FIG. [Figure 19] FIG. [Figure 20] FIG. 2 is a perspective view of the housing with the cover removed. [Figure 21] FIG. 2 is a plan view of the housing with the cover removed. [Figure 22] 1 is a longitudinal cross section of the main body in the front-to-rear direction. [Figure 23] FIG. [Figure 24] FIG. 10 is a plan view of an electrical component according to another embodiment. [Figure 25] FIG. 2 is a right side view of a controller for a work vehicle provided in a bonnet portion. [Figure 26] FIG. 2 is a perspective view of the storage case with the lid portion open. [Figure 27] FIG. 2 is a perspective view of the storage case with the lid closed. [Figure 28]FIG. 2 is a perspective view of a front body portion and a rear body portion that form the body portion of the storage case. [Figure 29] FIG. 10 is a left side view of the biasing member that connects the main body and the lid. [Figure 30] FIG. 2 is a perspective view of a charging cable. DETAILED DESCRIPTION OF THE INVENTION

[0016] As shown in Figure 1, a riding lawnmower or other work vehicle has a pair of left and right front wheels 2 at the front of its body 1, a pair of left and right rear wheels 3 at the rear of its body 1, and a work implement 4 for cutting grass or the like between the front wheels 2 and rear wheels 3 on the underside of the body 1. A bonnet 5 is provided at the front of the upper part of the body 1, and a control unit 6 on which an operator rides is provided behind the bonnet 5. A safety frame (ROPS) 7 for protecting the operator is provided behind the control unit 6, and a grass collection container 8 for collecting grass or the like cut by the work implement 4 is provided below the safety frame 7.

[0017] 2 and 3, a battery 50 that stores electricity to be supplied to an electric motor (referred to as a "first electric motor" in the claims) 30 that drives the rear wheels 3 and an electric motor (referred to as a "second electric motor" in the claims) 40 that drives the work equipment 4 is provided in the bonnet section 5, and the battery 50 is covered by a bonnet cover 5A. The bonnet cover 5A is supported by a support shaft (not shown) that extends in the left-right direction and is provided at the front of the traveling body 1. This makes it possible to effectively utilize the space formed in the bonnet section 5 and also to suppress differences in the weight balance in the front-to-rear direction of the work vehicle.

[0018] A pilot's seat 60 is provided at the rear of the control unit 6, and a steering wheel 62 is provided in front of the pilot's seat 60. The steering wheel 62 is supported on the upper part of a steering shaft 63 that extends in the vertical direction, and the steering shaft 63 is supported by the steering post 11.

[0019] On the left fender 64L on the left side of the operator's seat 60, there is provided a cleaner lever 65 for operating a cleaner (not shown) that forcibly conveys grass clippings remaining in a chute 46 that conveys grass clippings cut by the work implement 4 to the grass collection bin 8, and a storage case 90 behind the cleaner lever 65 that stores a charging cable 95 used to charge the battery 50. As a result, when the charge level of the battery 50 falls below a predetermined level, the work vehicle can be moved to a nearby warehouse or the like without having to be moved to a charging station, and the battery 50 can be charged by connecting the charger 73 to a household outlet provided in the warehouse or the like with the charging cable 95. The input voltage of the charger 73 is configured to correspond to AC voltages of 100 to 240V. On the right fender 64R of the operator's seat 60, there is provided a lifting lever 66 that controls the elevation and lowering of the work implement 4.

[0020] A brake pedal 68 is provided on the left side of the steering post 11 on the floor 67 of the control unit 6, and forward and reverse accelerator pedals 69 are provided on the right side.

[0021] Electrical components 61 are provided below the cockpit 60 of the control section 6. This allows the space formed below the cockpit 60 to be used effectively.

[0022] The safety frame 7 is formed from a left support pillar 7L extending in the vertical direction, a right support pillar 7R extending in the vertical direction, and an inverted U-shaped connecting portion 7A connecting the upper parts of the left support pillar 7L and the right support pillar 7R.

[0023] 4 to 7, an electric motor 30, such as a synchronous motor or an induction motor, which is operated with a three-phase AC voltage waveform and drives the rear wheels 3, is provided below the electrical components 61. An output shaft (referred to as the "first output shaft" in the claims) 30A formed to extend in the left-right direction of the electric motor 30 is connected to the upper part of a gearbox 31 which reduces the speed of the output rotation transmitted from the output shaft 30A to increase the output torque or reverse the direction of rotation. The electric motor 30 is provided at a position offset from the center in the left-right direction towards the left rear wheel 3L.

[0024] The output rotation increased or decreased by the gearbox 31 is transmitted to a drive shaft 33 extending in the left-right direction via a differential gear 32 formed by a differential gear or the like, which is provided below the gearbox 31. The output rotation transmitted to the drive shaft 33 is transmitted to a left rear wheel 3L and a right rear wheel 3R supported at both ends of the drive shaft 33.

[0025] An electric motor 40, such as a synchronous motor or induction motor, is provided below the electric motor 30 and is operated with a three-phase AC voltage waveform to drive the work machine 4. An output shaft (referred to as the "second output shaft" in the claims) 40A extending in the front-rear direction of the electric motor 40 is connected to the rear of a universal joint 41 also extending in the front-rear direction. The output shaft 40A is provided above the drive shaft 33 and perpendicular to the drive shaft 33. This allows the space below the electric motor 30 to be effectively utilized. Furthermore, the transmission path between the electric motor 40 and the work machine 4 can be shortened, allowing the output rotation of the electric motor 40 to be efficiently transmitted to the work machine 4. The electric motor 40 is provided in a position offset toward the left rear wheel 3L from the center in the left-right direction.

[0026] The front portion of the universal joint 41 is connected to a gearbox 42 that reduces the speed of the output rotation transmitted from the universal joint 41 and increases the output torque. The output rotation transmitted to the gearbox 42 is transmitted to a left cutting blade (not shown) provided in the left discharge passage 45L of the work implement 4 via an output shaft formed to extend in the vertical direction of the gearbox 42.

[0027] A connecting member 43 extending in the left-right direction is connected to the right part of the gearbox 42, and the right part of the connecting member 43 is connected to the gearbox 44. The output rotation transmitted to the gearbox 44 is transmitted to a right cutting blade (not shown) provided in the right discharge passage 45R of the work implement 4 via an output shaft formed to extend in the up-down direction of the gearbox 44. The output rotations of the output shafts of the gearbox 42 and gearbox 44 rotate at the same rotational speed but in opposite directions; that is, in a plan view, the output shaft of the gearbox 42 rotates clockwise and the output shaft of the gearbox 44 rotates counterclockwise.

[0028] As shown in FIG. 8 , the rotational speeds of the left and right cutting blades can be increased or decreased by operating the gearshift lever 47 provided on the left side of the steering wheel 62. When the gearshift lever 47 is in the neutral position, the output rotation of the electric motor 40 is zero, and the rotational speeds of the left and right cutting blades are also zero. When the gearshift lever 47 is moved from the neutral position to the forward tilt position, the output rotation of the electric motor 40 is increased or decreased in accordance with the magnitude of the tilt angle of the forward tilt position, and the rotational speeds of the left and right cutting blades are also increased or decreased. When the gearshift lever 47 is moved from the neutral position to the rearward tilt position, the output rotation of the electric motor 40 is increased or decreased in accordance with the magnitude of the tilt angle of the rearward tilt position, and the rotational direction of the output rotation of the electric motor 40 is reversed, and the rotational speeds of the left and right cutting blades are also increased or decreased, and the rotational directions of the left and right cutting blades are reversed.

[0029] The discharge outlets of the left discharge passage 45L and the right discharge passage 45R are connected to the inlet of a chute 46 that transports cut grass and the like to the grass collection container 8. The discharge outlet of the chute 46 is connected to the inlet of the grass collection container 8.

[0030] In a plan view, the front of the chute 46 is provided to the right of the universal joint 41, and the rear of the chute 46 is provided to the right of the gearbox 31, and in a rear view, the chute 46 and grass collection container 8 are provided between the gearbox 31 and the right rear wheel 3R. This allows a large chute 46 to be provided in the space formed to the right of the universal joint 41 and gearbox 31, and grass and the like cut by the work implement 4 can be efficiently transported to the grass collection container 8.

[0031] In a side view, the upper wall of the chute 46 is formed with an upward slope toward the rear, and the rear portion of the chute 46 is provided extending downward below the electrical component 61. This makes the rear portion of the chute 46 larger, making it possible to prevent the inside of the chute 46 from becoming clogged with grass or the like.

[0032] As shown in FIGS. 9 and 10, the vehicle body 1 is formed of a vehicle body main body 10 that supports the front wheels 2 and the rear wheels 3, and a steering post 11 that supports the steering shaft 63.

[0033] The vehicle body 10 is formed with a left front-rear frame 10L and a right front-rear frame 10R extending in the fore-and-aft direction, and the lower part of the steering post 11 is formed with a left connecting portion 11L and a right connecting portion 11R extending forward.

[0034] The left connecting portion 11L is fixed to the left front and rear frame 10L by fastening means such as bolts, and the right connecting portion 11R is fixed to the right front and rear frame 10R by fastening means such as bolts, and these are integrated to form the traveling vehicle body 1.

[0035] A left support member 12L is provided at the front of the left front-rear frame 10L, and the connecting portion of the left support member 12L is inclined upward to the left. Also, a right support member 12R is provided at the front of the right front-rear frame 10R, and the connecting portion of the right support member 12R is inclined upward to the right. The left support member 12L and the right support member 12R are made of channel steel.

[0036] A left support member 13L is provided in front of the left connecting portion 11L, and the connecting portion of the left support member 13L is formed with an upward slope to the left. Also, a right support member 13R is provided in front of the right connecting portion 11R, and the connecting portion of the right support member 12R is formed with an upward slope to the right. The left support member 13L and the right support member 13R are made of channel steel.

[0037] At the bottom of the steering post 11, protrusions 14 are formed that protrude forward at a predetermined interval in the left-right direction, and a buffer member 15 made of a rubber material or the like is provided at the tip of the protrusions 14.

[0038] A left upper and lower frame 20L extending upward is provided at the rear of the left front and rear frame 10L, and a right upper and lower frame 20R extending upward is provided at the rear of the right front and rear frame 10R, and the upper parts of the left upper and lower frame 20L and the right upper and lower frame 20R are connected to a left and right frame 21 extending in the left-right direction.

[0039] A left connecting portion 22L is provided on the left part of the left / right frame 21, which supports the lower part of the left support portion 7L of the safety frame 7, and a right connecting portion 22R is provided on the right part of the left / right frame 21, which supports the lower part of the right support portion 7R of the safety frame 7.

[0040] As shown in FIGS. 11 and 12 , the hood section 5 is provided with a battery 50 that stores power supplied to the electric motor 30 that drives the rear wheels 3 and the electric motor 40 that drives the work implement 4, and a battery 55 that stores power supplied to a work vehicle controller 77 that controls the electronic devices mounted on the traveling vehicle body 1. The controller 77 controls the electronic devices of the entire work vehicle by outputting a signal to control the electric motor 30 via an inverter device 81 in response to operation input of the accelerator pedal 69, and by outputting a signal to control the electric motor 40 via an inverter device 82 in response to operation input of the gear shift lever 47. In this embodiment, the battery 50 is formed of a lithium-ion battery with high energy density, and the battery 55 is formed of a lead battery. FIGS. 11 and 12 also show a right battery 50R that forms the battery 50, and a configuration in which a spacer 56 is provided to the left of the right battery 50R in place of the left battery 50L.

[0041] The spacer 56 and right battery 50R are fixed to the vehicle body 10 and steering post 11 via the battery bracket 52. The battery 55 is mounted on the upper surface of a support member 57 that extends forward from the front of the left and right front frames 52A of the battery bracket 52. This allows for efficient maintenance and inspection of the batteries 50 and 55, and also prevents rainwater from splashing on the batteries 50 and 55.

[0042] A protective frame 25 is provided in the middle of the spacer 56 and the right battery 50R in the fore-and-aft direction, extending along the outer periphery of the spacer 56 and the right battery 50R. This prevents the battery 50 from being damaged when the work vehicle tips over.

[0043] As shown in FIG. 13, the battery 50 provided in the hood section 5 is composed of a left battery 50L provided on the left side and a right battery 50R provided on the right side. The left battery 50L and the right battery 50R are formed by connecting multiple high-energy-density lithium-ion batteries in series and parallel, and are formed with the same shape and capacity. This allows the left battery 50L and the right battery 50R to be provided in the hood section 5 and connected in parallel, allowing the work vehicle to be driven for long periods of time to mow grass in a large park, etc. Furthermore, when mowing grass in a small park, either the left battery 50L or the right battery 50R can be removed from the hood section 5 and used as a replacement battery.

[0044] When the left battery 50L and the right battery 50R are connected in parallel, the upper front portions of the left battery 50L and the right battery 50R are connected by a front connecting plate 51A, and the upper rear portions of the left battery 50L and the right battery 50R are connected by a rear connecting plate 51B. This firmly connects the upper portions of the left battery 50L and the right battery 50R via the front connecting plate 51A and the rear connecting plate 51B, preventing breakage of cables connecting the terminals of the left battery 50L and the right battery 50R. Furthermore, the lower portions of the left battery 50L and the right battery 50R are fitted within the inner periphery of the battery bracket 52. This allows the space formed in the hood portion 5 to be effectively utilized.

[0045] 11 and 12, when the left battery 50L is removed and only the right battery 50R is used, a spacer 56 is provided to the left of the right battery 50R, which has the same shape and weight as the left battery 50L in a plan view. This prevents the center of gravity of the work vehicle from shifting significantly, preventing any discomfort that may occur when operating the vehicle.

[0046] 14, the battery bracket 52 is formed of a left front-rear frame 52L and a right front-rear frame 52R extending in the front-rear direction, a front left-right frame 52A connecting the front portions of the left front-rear frame 52L and the right front-rear frame 52R, and a rear left-right frame 52B connecting the rear portions of the left front-rear frame 52L and the right front-rear frame 52R. The left front-rear frame 52L and the right front-rear frame 52R are formed from angle steel, and the front left-right frames 52A and the rear left-right frames 52B are formed from channel steel.

[0047] The connecting portion of the left front and rear frame 52L is inclined upward to the left, and the connecting portion of the right front and rear frame 52R is inclined upward to the right. In rear view, the connecting portions of the left support member 13L, the left support member 12L, and the left front and rear frame 52L are inclined upward to the left at the same inclination angle, and the connecting portions of the right support member 12R, the right support member 12R, and the right front and rear frame 52R are inclined upward to the right at the same inclination angle.

[0048] A round left vibration-damping member 53L is provided on the underside of the connecting portion of the left front-rear frame 52L at a predetermined distance in the front-rear direction, and a round right vibration-damping member 53R is provided on the underside of the connecting portion of the right front-rear frame 52R at a predetermined distance in the front-rear direction.

[0049] The left front and rear frame 52L is connected to the left support member 12L of the left front and rear frame 10L and the left support member 13L of the left connecting portion 11L via a left vibration isolating member 53L, and the right front and rear frame 52R is connected to the right support member 12R of the right front and rear frame 10R and the right support member 13R of the right connecting portion 11R via a right vibration isolating member 53R. This prevents vibrations of the traveling vehicle body 10 that occur when the work vehicle is traveling from being transmitted to the battery 50, thereby preventing damage to the battery 50.

[0050] As shown in Figure 15, the connecting portion of the left front and rear frame 52L has a slope that slopes upward to the left, perpendicular to a left imaginary line 54L that connects the center of the left vibration-isolating member 53L and the center of the left front wheel 2L on the left side. The connecting portion of the right front and rear frame 52R has a slope that slopes upward to the right, perpendicular to a right imaginary line 54R that connects the center of the right vibration-isolating member 53R and the center of the right front wheel 2R on the right side. This makes it possible to suppress large vibrations caused by unevenness in the road surface via the front wheels 2 and rear wheels 3, thereby preventing damage to the battery 50. Reference numeral 35 denotes a front wheel support frame that supports the left and right front wheels 2, and reference numeral 36 denotes a connecting portion between the front wheel support frame and the vehicle body 10, and indicates the swing axis of the front wheel support frame.

[0051] Additionally, the tip of the buffer member 15 of the steering post 11 is pressed against the rear surfaces of the left and right rear frames 52B of the battery bracket 52. This prevents the battery 50 from moving rearward when the work vehicle starts, thereby preventing damage to the battery 50.

[0052] As shown in FIG. 16, the protective frame 25 is formed by upper and lower protective frames 26 extending in the vertical direction, and front and rear protective frames 27 extending rearward from the vertical middle of the upper and lower protective frames 26.

[0053] The upper and lower protective frames 26 are formed from a left upper and lower frame 26L extending upward from the left front and rear frame 10L, a right upper and lower frame 26R extending upward from the right front and rear frame 10R, and an inverted U-shaped connecting portion 26A connecting the upper parts of the left upper and lower frame 26L and the right upper and lower frame 26R.

[0054] The left upper and lower frame 26L is provided on the left side of the left face of the left battery 50L, the right upper and lower frame 26R is provided on the right side of the right face of the right battery 50R, and the connecting portion 26A is provided on the upper side of the top faces of the left battery 50L and the right battery 50R. The left upper and lower frame 26L, the right upper and lower frame 26R, and the connecting portion 26A are formed from square pipes.

[0055] The front and rear protective frame 27 is formed of a left front and rear frame 27L extending rearward from a vertically intermediate portion of the left upper and lower frame 26L, a right front and rear frame 27R extending rearward from a vertically intermediate portion of the right upper and lower frame 26R, and a connecting portion 27A extending in the left-right direction connecting the rear portions of the left front and rear frame 27L and the right front and rear frame 27R. The connecting portion 27A is detachably fixed to the lower portion of the steering post 11 with fastening means such as bolts. This increases the rigidity of the protective frame 25, suppresses deformation of the protective frame 25 when the work vehicle overturns, and further prevents damage to the battery 50. Note that in this embodiment, the protective frame 27 is fixed to the lower portion of the steering post 11 via the connecting portion 27A, but the rear portions of the left front and rear frame 27L and the right front and rear frame 27R can also be fixed to the lower portion of the steering post 11 without providing the connecting portion 27A.

[0056] The left front and rear frame 27L is provided on the left side of the left face of the left battery 50L, the right front and rear frame 27R is provided on the right side of the right face of the right battery 50R, and the connecting portion 27A is provided on the rear side of the rear faces of the left battery 50L and the right battery 50R. The left front and rear frame 27L and the right front and rear frame 27R are formed from square pipes, and the connecting portion 27A is formed from channel steel.

[0057] 17, in a side view, an imaginary line 28 connecting the top of the connecting portion 26A of the upper and lower protective frames 26 and the base of the connecting portion 7A of the safety frame 7 is formed so as to be positioned above the steering wheel 62. This forms a large protective space below the imaginary line 28, preventing the worker from colliding with external tree branches, etc. while the work vehicle is traveling, thereby improving work safety.

[0058] 18 and 19, the electrical component 61 is made up of an electrical box 70 in which an inverter device (referred to as the "first inverter device" in the claims) 81 to which high-voltage power is supplied is provided, and a charger 73 used when charging the battery 50, which is provided below the electrical box 70. In a side view, the front of the electrical box 70 is provided further forward than the front of the driver's seat 60, and the front of the charger 73 is provided further forward than the front of the electrical box 70. This forms a large space behind the electrical box 70 and the charger 73, and by providing an upper wall of the chute 46 that is sloped upward at the rear in this space, the vertical cross-sectional area of ​​the chute 46 in the left-right direction can be made large, and clogging of the interior of the chute 46 with grass clippings can be prevented.

[0059] The electrical box 70 is made up of a main body 70A that houses the inverter device 81 and other components, and a lid 70B. The lid 70B is swingably supported on a support shaft 70C that extends in the left-right direction and is provided at the front of the main body 70A. In addition, in a side view, the top surface of the lid 70B is formed with an upward slope toward the rear. This prevents rainwater from accumulating on the top surface of the lid 70B.

[0060] The main body 70A is attached to support members 16A extending in the front-to-rear direction and provided on both sides of left and right frames 16 extending in the left-to-right direction at the rear of the traveling vehicle body 10, via grommets 71 provided at the four corners of the underside of the main body 70A. This prevents vibrations of the traveling vehicle body 10 that occur when the work vehicle is traveling from being transmitted to the inverter device 81, etc., thereby preventing damage to the inverter device 81, etc.

[0061] The charger 73 is attached to support members 18 that extend in the left-right direction and have a predetermined length in the front-to-rear direction and are provided on left and right frames 17 that are provided in front of the left and right frames 16 of the traveling vehicle body 10, via grommets 74 provided at the four corners of the underside of the charger 73. This prevents vibrations of the traveling vehicle body 10 that occur when the work vehicle is traveling from being transmitted to the charger 73, preventing damage to the charger 73.

[0062] The middle part of support member 18 in the front-to-rear direction is formed to protrude downward further than the front and rear parts of support member 18, and ventilation holes 18A for ventilating outside air are formed in the middle part, and a fan 75 for forcibly ventilating outside air is provided on the top surface of charger 73. This prevents charger 73 from becoming excessively hot during use, and prevents damage to the electrical components that make up charger 73.

[0063] 20 to 22, a left terminal block 80L and a right terminal block 80R are provided on the left front portion of the bottom wall of the main body 70A, an inverter device 81 that generates a three-phase AC voltage waveform to operate the electric motor 30 and an inverter device (referred to as a "second inverter device" in the claims) 82 that generates a three-phase AC voltage waveform to operate the electric motor 40 are provided on the left rear portion of the bottom wall of the main body 70A, and a converter device 83 that converts the 45V DC voltage supplied from the battery 50 to a 12V DC voltage supplied when charging the battery 55 is provided between the right terminal block 80R and the inverter device 82. This allows the inverter device 81 and other components heated by the bottom wall of the main body 70A, which is cooled by outside air, to be efficiently cooled. In this specification, the left terminal block 80L and the right terminal block 80R are collectively referred to as terminal blocks 80.

[0064] A data transfer device 84 such as an isolated CAN transceiver that transfers data between the controller 77 and the inverter devices 81, etc., is provided on the right side of the inverter device 82 on the bottom wall of the main body 70A. This can block noise such as electromagnetic waves generated by the inverter devices 81, etc., improving the reliability of data transfer. Furthermore, via the data transfer device 84, electrical signals can be communicated between the controller 77, which is powered by the 12V battery 55, and the inverter devices 81, etc., which are powered by the 45V battery 50.

[0065] Cable 85A connecting battery 50 and terminal block 80 and cable 85B connecting controller 77 and data transfer device 84 are routed through inner peripheries of grommets provided in an opening in the front wall of electrical box 70, while cable 86A connecting electric motor 30 and inverter device 81 and cable 86B connecting electric motor 40 and inverter device 82 are routed through inner peripheries of grommets provided in an opening in the rear wall of electrical box 70. This improves the airtightness of electrical box 70 and prevents rainwater and dust from entering electrical box 70. Furthermore, as shown in FIG. 23 , electric motors 30 and 40 are provided below inverter devices 81 and 82 provided in the left rear portion of main body 70A. This allows the lengths of cables 86A and 86B to be shortened, facilitating the routing of cables 86A and 86B.

[0066] The left terminal block 80L and the right terminal block 80R are connected to the inverter device 81, the left terminal block 80L and the right terminal block 80R are connected to the inverter device 82, and the inverter device 81 is connected to the inverter device 82 by a metal plate-shaped bus bar 87. This allows efficient routing of the left terminal block 80L and the inverter device 81, etc.

[0067] <Electrical components according to other embodiments> An electrical component according to another embodiment is shown in Fig. 24. Note that the same members as those in the electrical component 61 described above are given the same reference numerals and the description thereof will be omitted.

[0068] In another embodiment, electrical component 61 houses a charger 73 in electrical box 70. A left terminal block 80L and a right terminal block 80R are provided on the left front portion of the bottom wall of main body 70A of electrical box 70, and charger 73 is provided behind left terminal block 80L. This eliminates the need for a support member 18 or the like for supporting charger 73, allowing the number of parts to be reduced. In addition, a converter device 83 is provided behind right terminal block 80R, a data transfer device 84 is provided to the right of converter device 83, and inverter devices 81 and 82 are provided behind data transfer device 84.

[0069] As shown in Fig. 25, a rectangular support member 76 extending in the front-to-rear direction is provided on the upper right and lower frames 26R of the upper and lower protective frames 26 provided on the bonnet portion 5. A controller 77 for the work vehicle is provided on the rear part of the right surface of the support member 76, and a relay 78 and a fuse 79 are provided on the front part. Note that 12V DC power is supplied to the controller 77, relay 78, and fuse 79 from the battery 55. This allows the controller 77 to be provided at a distance from the inverter devices 81, 82, making it possible to prevent malfunctions caused by noise such as electromagnetic waves generated by the inverter devices 81, 82.

[0070] As shown in FIGS. 26 and 27, the storage case 90 is formed of a rectangular parallelepiped main body 91 that stores a charging cable 95, and a lid 92 provided on the top of the main body 91.

[0071] As shown in FIG. 28 , the main body 91 is formed from a front main body 91A that forms the front, left, right, and bottom walls of the main body 91, and a rear main body 91B that forms the rear, left, right, and bottom walls of the main body 91. The front main body 91A and the bottom wall of the rear main body 91B are fastened together with fastening means such as bolts. This allows the main body 91 to be easily assembled by fastening the front main body 91A and the rear main body 91B together. In addition, an edge 91C extending toward the outer periphery is formed on the upper part of the rear main body 91B. This allows the storage case 90 to be easily attached to the left fender 64L by inserting the storage case 90 from above the opening of the left fender 64L and engaging the edge 91C with the top surface of the left fender 64L.

[0072] As shown in Figure 29, the connecting portion 92A of the lid portion 92 is rotatably supported on a support shaft 91D extending in the left-right direction and provided at the top of the rear wall of the rear main body portion 91B. The front portion of the connecting portion 92A and a stay 91E erected facing rearward on the rear wall of the rear main body portion 91B are connected by a biasing member 93 such as a spring. This prevents the lid portion 92 from being left closed. When the lid portion 92 is opened by rotating it clockwise to the maximum extent as viewed from the axis of the support shaft 91D, the biasing member 93 can be moved beyond the dead point and maintained in the open position.

[0073] As shown in FIG. 30, a plug 95A for connecting to a household outlet is formed at one end of the charging cable 95, and a plug 95B for connecting to the connection terminal of the charger 73 is formed at the other end. [Explanation of symbols]

[0074] 1 Running vehicle 2 front wheels 3 rear wheels 4 Work equipment 5. Bonnet 6 Control Unit 8 Grass collection container 30 Electric motor (1st electric motor) 30A output shaft (first output shaft) 31 Gearbox 33 Drive shaft 40 Electric motor (second electric motor) 40A output shaft (second output shaft) 46 Shooter 50 Battery 60 cockpit 70 Electrical box 73 Charger 77 Controller 81 Inverter device (first inverter device) 82 Inverter device (second inverter device) 84 Data transfer device

Claims

1. A work vehicle having a pair of left and right front wheels (2) at the front of a traveling body (1), a pair of left and right rear wheels (3) at the rear of the traveling body (1), a work implement (4) for cutting weeds between the front wheels (2) and rear wheels (3) of the traveling body (1), a bonnet section (5) having a predetermined space at the front of the traveling body (1), a control section (6) for a driver to ride in at the rear of the bonnet section (5), and a grass collection container (8) for storing weeds cut by the work implement (4) at the rear of the control section (6), A battery (50) is provided in the bonnet portion (5), A first electric motor (30) for driving the rear wheels (3) and a second electric motor (40) for driving a working machine (4) are provided at the rear of the traveling vehicle body (1), In a side view, an electrical box (70) is provided between a driver's seat (60) of the control section (6) and a chute (46) that connects the discharge outlet of the work machine (4) with the inlet of the grass collection container (8), a first inverter device (81) for driving the first electric motor (30) and a second inverter device (82) for driving the second electric motor (40) are provided in the electrical equipment box (70); A controller (77) for controlling electronic devices mounted on the traveling vehicle body (1) is provided at a position separated from the electrical equipment box (70), A work vehicle characterized in that the controller (77) is provided inside a bonnet portion (5).

2. A work vehicle as described in claim 1, wherein a first output shaft (30A) of the first electric motor (30) is arranged along the left-right direction, and a second output shaft (40A) of the second electric motor (40) is arranged along the front-to-rear direction.

3. A gearbox (31) is provided on one side of the first electric motor (30) to decelerate the output rotation of the first output shaft (30A) and switch the rotation direction, The rear wheel (3) and the gearbox (31) are connected by a drive shaft (33) extending in the left-right direction, and the first electric motor (30) is provided above the second electric motor (40) in rear view; 3. The work vehicle according to claim 2, wherein the second output shaft (40A) is provided above the drive shaft (33).

4. A work vehicle as described in claim 2 or 3, wherein, when viewed from the rear, the first electric motor (30) and the second electric motor (40) are offset to one side in the left-right direction, and the chute (46) and grass collection container (8) are provided on the other side in the left-right direction.

Citation Information

Patent Citations

  • Electric working vehicle

    JP2011218951A