Electric roller

Abstract

To provide an electric roller capable of preventing a vehicle from making unintended movement while increasing the uptime of a battery by reducing electric power consumption.SOLUTION: An electric roller 1D includes: a rolling wheel electric motor; a rolling wheel inverter; a battery for supplying electric power; and a control unit 3D that outputs a signal to the rolling wheel inverter in accordance with inclination of a forward / reverse lever. The electric roller does not comprise any internal combustion engine, and uses only the battery as a power source of the rolling wheels. The control unit 3D has a standby mode in which the control unit 3D is activated but the rolling wheel inverter is not activated, and a ready mode in which the control unit 3D and the rolling wheel inverter are activated and the forward / reverse lever is positioned in a neutral position, thereby enabling the vehicle to travel. When a parking brake is released during the ready mode and the state in which the forward / reverse lever is in the neutral position continues for a predetermined time, the mode is switched to the standby mode.SELECTED DRAWING: Figure 30

Description

[Technical field]

[0001] The present invention relates to a motorized roller. [Background technology]

[0002] For example, Patent Document 1 discloses a rolling vehicle (roller) that compacts road surfaces. A conventional rolling roller includes a pair of rolling wheels, a vehicle body frame, an engine, a hydraulic pump, and a hydraulic motor for traveling. A conventional rolling roller travels by driving a hydraulic pump with the engine, and rotating the hydraulic motor for traveling with the hydraulic pressure. In addition, the oil discharge force is adjusted according to the input amount of a forward / reverse lever, thereby accelerating, decelerating, or stopping the vehicle. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2010-149784 A Summary of the Invention [Problem to be solved by the invention]

[0004] In recent years, efforts to realize a decarbonized society that aims to eliminate greenhouse gas emissions that cause global warming have been underway worldwide. However, conventional compaction rollers use engines, which consume fossil fuels and produce CO 2 They also emit greenhouse gases such as carbon dioxide and oxygen. In addition, the use of engines increases noise and heat emissions, which increases the burden on operators in confined spaces such as tunnels, and also has a negative impact on the work environment (people, structures, trees, etc.) at construction sites. Furthermore, conventional compaction rollers have problems with poor maintenance, such as hydraulic oil leaks and increased frequency of hydraulic oil changes.

[0005] Research is also underway to electrify compaction rollers. The electric motors of the electric rollers under research are silent, so there is a risk that the operator will not realize that the roller is ready to run, resulting in unnecessary consumption of battery power. In addition, while engine vehicles emit engine noise, making it clear that they are ready to run, electric rollers are silent, making it difficult to intuitively tell whether they are ready to run or in standby. Therefore, there is a risk that the vehicle will move unintentionally due to erroneous operation by an operator who assumes it is in standby.

[0006] Therefore, the objective of the present invention is to provide an electric roller that can prevent unintended movement of the vehicle, improve battery operating time by reducing power consumption, and easily control speed, thereby contributing to a carbon-free society, improving the working environment, and improving maintainability. [Means for solving the problem]

[0007] The electric roller of the present invention comprises a pair of rolling wheels respectively installed at the front and rear, a vehicle body frame rotatably supporting the rolling wheels, an electric motor for rolling wheels which drives the rolling wheels, a rolling wheel inverter which controls the rotation speed of the electric motor for rolling wheels, a battery which supplies power to the electric motor for rolling wheels and the inverter for rolling wheels, and a control unit which outputs a signal to the inverter for rolling wheels in accordance with the inclination of a forward / reverse lever, and does not comprise an internal combustion engine, the power source for the rolling wheels is the battery alone, and the control unit is activated to drive the inverter for rolling wheels. The vehicle has a standby mode in which the electric motor for the rolling wheels is not activated and the inverter is on standby; a ready mode in which the control unit and the inverter for the rolling wheels are activated and the forward / reverse lever is in the neutral position, thereby enabling the vehicle to run; and a run mode in which the electric motor for the rolling wheels is driven and the vehicle is running when the forward / reverse lever is in the forward or reverse position.When the parking brake is released during the ready mode and the forward / reverse lever remains in the neutral position for a predetermined period of time, the vehicle switches to the standby mode.

[0008] According to the present invention, fuel consumption and greenhouse gas emissions can be substantially eliminated by electrification. Furthermore, since noise can be reduced and greenhouse gas emissions can be substantially eliminated by electrification, the burden on the operator can be reduced and the working environment can be improved. Furthermore, there is no need to change hydraulic oil, and maintenance is excellent. Furthermore, the inclusion of an inverter for the rolling wheels makes it easy to control the speed. Furthermore, according to the present invention, the ready mode is automatically switched to the standby mode under predetermined conditions, so that the battery operating time can be improved by reducing power consumption. Furthermore, according to the present invention, the vehicle automatically switches to a standby mode in which the vehicle cannot be driven under specified conditions, thereby preventing the vehicle from moving unintentionally due to an operator's erroneous operation.

[0009] It is also preferable that the control section can arbitrarily set the predetermined time period.

[0010] According to the present invention, it is possible to set the predetermined time period according to the skill of the operator, and therefore it is possible to achieve both ease of operation and reduction in power consumption. Effect of the Invention

[0011] According to the present invention, it is possible to prevent unintended movement of the vehicle and improve the battery operating time by reducing power consumption, while also making it easy to control speed, thereby contributing to a carbon-free society, improving the working environment, and improving maintainability. [Brief description of the drawings]

[0012] [Figure 1] FIG. 2 is a side view of the electric roller according to the first embodiment of the present invention. [Diagram 2] FIG. 2 is a plan view of the electric roller according to the first embodiment. [Diagram 3] FIG. 2 is a rear view of the electric roller according to the first embodiment. [Figure 4] FIG. 2 is a block diagram showing a configuration of an electric roller according to the first embodiment. [Diagram 5] 5A to 5C are schematic diagrams illustrating the operation of the electric roller according to the first embodiment. [Figure 6] FIG. 2 is a block diagram showing a power supply system and a control system of the electric roller according to the first embodiment. [Figure 7] FIG. 2 is a rear view showing the dashboard of the electric roller according to the first embodiment. [Figure 8] FIG. 2 is a side view showing a dashboard of the electric roller according to the first embodiment. [Figure 9] FIG. 4 is a side view showing a brake pedal in the electric roller according to the first embodiment during forward movement. [Figure 10] FIG. 4 is a side view showing the electric roller according to the first embodiment when the brake pedal is depressed. [Figure 11] FIG. 2 is a partially see-through side view of the electric roller according to the first embodiment. [Figure 12] FIG. 2 is a partially transparent plan view of the electric roller according to the first embodiment. [Figure 13] FIG. 2 is a cross-sectional view showing a front wheel of the electric roller according to the first embodiment. [Figure 14] FIG. 2 is a plan view showing a first gear box of the electric roller according to the first embodiment. [Figure 15] 15 is a cross-sectional view taken along the line XV-XV of FIG. 14. [Figure 16] 16 is a cross-sectional view taken along line XVI-XVI of FIG. 14. [Figure 17] FIG. 2 is a cross-sectional view showing the periphery of a rear wheel of the electric roller according to the first embodiment. [Figure 18] 18 is a cross-sectional view taken along line XVIII-XVIII of FIG. 17. [Figure 19] FIG. 2 is a side view showing the steering system of the electric roller according to the first embodiment. [Figure 20] FIG. 2 is a plan view showing a steering system for the electric roller according to the first embodiment. [Figure 21] 11 is a graph showing the relationship between time and rotation speed at startup in a comparative example. [Figure 22] 11 is a graph showing the relationship between time and rotation speed in a comparative example when the engine is stopped. [Diagram 23] 10 is a graph showing the relationship between time and rotation speed of the driving command value of the electric motor for the rolling wheel in the comparative example and the embodiment. [Figure 24] 4 is a graph showing the relationship between time and rotation speed at start-up in an embodiment. [Diagram 25] 11 is a graph showing the relationship between time and rotation speed in an embodiment when the engine is stopped. [Figure 26] 13 is a graph showing a drive command value of an electric motor for a rolling wheel according to a modified example, relative to time and rotation speed. [Figure 27] FIG. 11 is a cross-sectional view showing a front wheel of an electric roller according to a fourth embodiment. [Figure 28] FIG. 13 is a block diagram showing a configuration of an electric roller according to a fourth embodiment. [Figure 29] FIG. 13 is a plan view showing the upper surface of a dashboard of an electric roller according to a fourth embodiment. [Diagram 30] FIG. 11 is a block diagram showing a power supply system and a control system of an electric roller according to a fourth embodiment. [Diagram 31] FIG. 13 is a flow diagram of a control unit of an electric roller according to a fourth embodiment, illustrating the flow of auto standby control. [Diagram 32] FIG. 13 is a flow diagram of a control unit of an electric roller according to a fourth embodiment, illustrating a flow of normal charging. [Diagram 33] FIG. 13 is a flow diagram of a control unit of an electric roller according to a fourth embodiment, illustrating a flow for starting a charging mode during travel. [Diagram 34] FIG. 13 is a flow diagram of a control unit of an electric roller according to a fourth embodiment, illustrating a flow of charging during travel. [Diagram 35] FIG. 13 is a flow diagram of a control unit of an electric roller according to a fourth embodiment, illustrating a flow for ending a charging mode during travel. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] [First embodiment] The electric roller of the present invention will be described in detail with reference to the drawings. The embodiments and modifications described below are merely examples, and each embodiment and modification can be used in appropriate combination. The up / down, left / right, front / rear directions shown in the drawings correspond to the moving direction of the electric roller.

[0014] <Overall outline structure> As shown in FIGS. 1 to 4, the electric roller 1 mainly includes a front wheel R1, a rear wheel R2, a body frame 2, an electric motor M (M1 to M4), an inverter J (J1 to J4), a battery K (K1 to K3), and a control unit 3.

[0015] The front wheel R1 is rotatably supported by a pair of front wheel side plates SP1, SP2 provided at the front of the body frame 2. The front wheel R1 is a rolling wheel that rolls the road surface, and in this embodiment is composed of an integrated iron wheel. The front wheel R1 may be composed of multiple tires or multiple iron wheels.

[0016] The rear wheels R2 are rotatably supported at the rear of the body frame 2. The rear wheels R2 are rolling wheels that roll the road surface, and in this embodiment are composed of four tires (R2A, R2B, R2C, R2D). The rear wheels R2 may be composed of a single or multiple iron wheels.

[0017] The vehicle body frame 2 is a vehicle body that rotatably supports the front wheels R1 and the rear wheels R2. The vehicle body frame 2 includes a front frame 11, a rear frame 12, a driver's seat 13, and a dashboard 14. The front frame 11 has front wheel side plates SP1, SP2 fixed to the front part. A front space 15 that houses an inverter J and a battery K is formed inside the front frame 11. The rear frame 12 includes the driver's seat 13 and the dashboard 14, and a rear space 16 that houses an electric motor M, an inverter J, a gear box, etc. is formed inside. The rear space 16 includes a first rear space 16a formed below the feet of the driver's seat 13, and a second rear space 16b formed below the driver's seat 13. The front frame 11 and the rear frame 12 are connected via joint pins that are parallel to the vertical direction. The electric roller 1 of this embodiment is an articulated type, but may be a rigid type.

[0018] 4, the front wheel electric motor M1 is an electric motor that drives the front wheels R1. The front wheel electric motor M1 drives in response to a drive command value input from the control unit 3 to the front wheel inverter J1. The right rear wheel electric motor M2 is an electric motor that drives the rear wheel R2. The right rear wheel electric motor M2 drives in response to a drive command value input from the control unit 3 to the right rear wheel inverter J2.

[0019] The left rear wheel electric motor M3 is an electric motor that drives the rear wheel R2. The left rear wheel electric motor M3 is driven in response to a drive command value input from the control unit 3 to the left rear wheel inverter J3. The front wheel electric motor M1, the right rear wheel electric motor M2, and the left rear wheel electric motor M3 are collectively referred to as the "rolling wheel electric motors." In addition, the front wheel inverter J1, the right rear wheel inverter J2, and the left rear wheel inverter J3 are collectively referred to as the "rolling wheel inverters."

[0020] 4, the vibration electric motor M4 is an electric motor that drives the vibration shaft 130. The vibration electric motor M4 is driven in response to a drive command value input from the control unit 3 to the vibration inverter J4.

[0021] As shown in FIG. 6, the battery K is a component that supplies power to each component such as the electric motor M and the inverter J. In this embodiment, the battery K includes a 48V battery K1, a 24V battery K2, and a 12V battery K3, and is stored in a battery case KA (see FIG. 11) arranged in the front space 15. The 48V battery K1 and the 24V battery K2 are lithium-ion secondary batteries. The 12V battery K3 is a lead-acid battery. In this embodiment, three types of batteries with different voltages are provided for the battery K, but any number of types may be provided, or the battery K may be configured with a single voltage. The battery management unit 71 uses, for example, a BMU (Battery Management Unit). The control unit 3 is a controller that controls each component. The control unit 3 uses, for example, a VCU (Vehicle Control Unit). The battery K, the battery management unit 71, and the control unit 3 are capable of cooperating with each other through CAN communication for transmitting battery information.

[0022] As shown in FIG. 5, in the electric roller 1, the control unit 3 outputs a drive command value to the inverter J (J1 to J3) according to the tilt angle of the forward / reverse lever 17 by the operator OP. The electric motors M (M1 to M3) rotate according to the drive command value input to each inverter J, causing the vehicle to travel forward or backward. Conventionally, fuel such as gasoline was burned to operate a hydraulic pump using an internal combustion engine (engine, etc.) to drive the rolling wheels, whereas the electric roller 1 of this embodiment is different in that it does not have an internal combustion engine and uses only a battery K as the power source for the rolling wheels. Also, conventionally, the acceleration / deceleration of the vehicle's traveling speed was adjusted by hydraulic control, whereas the electric roller 1 of this embodiment is different in that it is controlled by a drive command value output from the control unit 3 to the inverter J.

[0023] <Running system> Next, the traveling system will be described in detail. As shown in Fig. 1 and Fig. 2, the driver's seat 13 is a portion where an operator OP sits, and faces the dashboard 14. The dashboard 14 is a box-shaped body installed in front of the driver's seat 13, and is provided with a brake pedal BP protruding rearward, and a display 18 is disposed on the upper surface. The steering wheel 19 is a device that determines the traveling direction of the vehicle, and is provided on the upper surface of the dashboard 14. The steering wheel 19 is connected to an orbitroll (registered trademark, the same applies below; see Figs. 4 and 19) 51 provided inside the dashboard 14.

[0024] 1, the brake pedal BP is provided at the bottom rear of the dashboard 14, and is configured to apply the brakes when the operator OP steps on it. The forward / reverse levers 17, 17 are provided on both sides of the dashboard 14, and are levers that can be tilted to a neutral position, a forward position, and a reverse position. The forward / reverse lever 17 may be configured to be provided on only one side of the dashboard 14.

[0025] As shown in Fig. 7, the forward / reverse levers 17, 17 are connected to both ends of a shaft 21. The shaft 21 is disposed inside the dashboard 14 along the width direction of the vehicle. As shown in Fig. 8, the shaft 21 is provided with a plate-shaped base plate 22 that rotates in synchronization with the shaft 21 and is fixed perpendicular to the shaft 21.

[0026] As shown in Fig. 9, the brake pedal BP is configured to move in conjunction with a shaft 21. A first pin 22a and a second pin 22b that protrude in the width direction of the vehicle are formed on the base plate 22. The first pin 22a and the second pin 22b are disposed at approximately the same distance from the shaft 21. The brake pedal BP includes a main body plate 23, a pedal portion 24, a rotation fulcrum portion 25, and a connecting fulcrum portion 26.

[0027] The main body plate 23 is a plate-like member having a pedal portion 24 at the rear. The front end of the main body plate 23 is rotatably fixed via a bracket 27 fixed to the front wall of the dashboard 14. The rotation fulcrum portion 25 serves as the rotation center of the brake pedal BP. The connecting fulcrum portion 26 is formed on the upper portion of the main body plate 23.

[0028] The connecting fulcrum portion 26 is connected to the base plate 22 via a first brake pedal rod 28 and a second brake pedal rod 29. The first brake pedal rod 28 and the second brake pedal rod 29 are rod-shaped members. The lower ends of the first brake pedal rod 28 and the second brake pedal rod 29 are connected to the connecting fulcrum portion 26 by pin connection.

[0029] An elongated hole 28a into which the first pin 22a fits loosely is formed at the upper end of the first brake pedal rod 28. An elongated hole 29a into which the second pin 22b fits loosely is formed at the upper end of the second brake pedal rod 29. When viewed from the side, the first brake pedal rod 28 and the second brake pedal rod 29 are V-shaped in side view.

[0030] In the initial position (when the forward / reverse lever 17 is in the neutral position), the base plate 22 is generally horizontal. The first pin 22a and the second pin 22b are located slightly above the center in the height direction of the long holes 28a and 29a.

[0031] Fig. 9 is an action diagram around the base plate 22 when the forward / reverse lever 17 is tilted to the maximum in the forward direction. As shown in Fig. 9, when the forward / reverse lever 17 is tilted forward, the shaft 21 and the base plate 22 rotate counterclockwise around the shaft 21. At this time, the first pin 22a is located at the upper end of the long hole 28a of the first brake pedal rod 28. On the other hand, the second pin 22b is located slightly below the center in the height direction of the long hole 29a of the second brake pedal rod 29. Even if the forward / reverse lever 17 is tilted forward, the position of the brake pedal BP does not change because the first pin 22a and the second pin 22b move within the long holes 28a, 29a.

[0032] Although not specifically shown in the drawings, when the forward / reverse lever 17 is tilted rearward to move the vehicle backward, the base plate 22 rotates clockwise in synchronization with the shaft 21. In this case, as in the case of forward movement, even if the forward / reverse lever 17 is tilted rearward, the first pin 22a and the second pin 22b move within the long holes 28a, 29a, respectively, so that the position of the brake pedal BP does not change.

[0033] Fig. 10 is an action diagram around the base plate 22 when the brake pedal BP is depressed. As shown in Fig. 10, when the operator OP depresses the brake pedal BP, the brake pedal BP rotates downward around the rotation fulcrum 25. As a result, the first brake pedal rod 28 and the second brake pedal rod 29 are pulled downward, so that the first pin 22a and the second pin 22b are positioned at the upper ends of the long holes 28a and 29a, respectively, and the base plate 22 rotates at a predetermined angle and becomes approximately horizontal. In synchronization with this, the shaft 21 and the forward / reverse lever 17 also rotate and are positioned in the neutral position, so that the brake is activated and braking is performed.

[0034] As described above, the operator OP can return the forward / reverse lever 17 to the neutral position or depress the brake pedal BP, thereby positioning the forward / reverse lever 17 in the neutral position and braking the vehicle. Details of the brake system will be described later.

[0035] As shown in Figs. 4 and 7, a potentiometer 31 is installed inside the dashboard 14. The potentiometer 31 is a device that detects the tilt angle of the forward / reverse lever 17. The shaft 21 is provided with a connecting plate 34 that protrudes in a direction perpendicular to the axial direction. Meanwhile, the potentiometer 31 is provided with a connecting plate 35 that is connected to the potentiometer 31 and rotates in synchronization with the connecting plate 34. Also, a connecting rod 33 that connects the connecting plates 34, 35 together is provided. By using a link mechanism formed by the connecting plates 34, 35 and the connecting rod 33, when the forward / reverse lever 17 is tilted, the tilt angle can be detected by the potentiometer 31. The detection result of the potentiometer 31 is output to the control unit 3.

[0036] 7, a limit switch (neutral sensor) 32 is installed inside the dashboard 14 near the shaft 21. The limit switch 32 is a device that detects the neutral position of the forward / reverse lever 17. The detection result of the limit switch 32 is output to the control unit 3.

[0037] Moreover, the display 18 provided on the upper surface of the dashboard 14 displays various vehicle information held by the control unit 3, such as a speedometer, remaining charge of the battery K, mileage, an hour meter, alert information, etc. The display 18 may be configured to display a touch-type operation panel. The display 18 may also display information related to compaction, such as the compaction status of the construction site, map information of the compacted area, and location information.

[0038] As shown in Figs. 4 and 6, a driving H / L switch 36, a parking switch 37, a vibration switch 39, a lighting switch, an alarm switch, etc. are provided on the upper surface of the dashboard 14.

[0039] The travel H / L switch 36 is a switch that allows the selection of a high-speed travel mode or a low-speed travel mode. When the forward / reverse lever 17 is fully tilted (full throttle), for example, the high-speed travel mode is set to 10 km / h and the low-speed travel mode is set to 5 km / h. These speeds can be set as appropriate.

[0040] The parking switch 37 is a switch that can select whether to activate or release the parking brake. The vibration switch 39 is a switch that can select whether to turn on or off the vibration of the front wheel R1. A switch that can control the intensity (number of rotations) of the vibration in conjunction with the vibration switch 39 may be provided. The lighting switch is, for example, a switch that can select whether to turn on or off the hazard lights that flash when stopping. The alarm switch is, for example, a switch that can select whether to turn on or off the backup buzzer when backing up. The ON or OFF state of these function switches (buttons) may be displayed on the display 18.

[0041] 4, the inverter J includes a front wheel inverter J1, a right rear wheel inverter J2, a left rear wheel inverter J3, and a vibration inverter J4. The inverter J is a device that controls the frequency based on a drive instruction value output from the control unit 3 and changes the rotation speed of each electric motor M.

[0042] 4, the electric motors M include a front wheel electric motor M1, a right rear wheel electric motor M2, a left rear wheel electric motor M3, and a vibration electric motor M4. The type of electric motor M may be appropriately selected, but in this embodiment, induction motors are used for all of them.

[0043] <Front wheel R1 structure (vibration system)> As shown in Fig. 13, the front wheel R1 is equipped with a roll 111, and a front wheel electric motor M1 and a vibration electric motor M4 are installed at both ends in the width direction of the vehicle. The roll 111 has a hollow cylindrical shape, and a first mirror plate 112 and a second mirror plate 113 are provided on the inner surface of the roll 111 with a gap therebetween. A hollow cylindrical vibration exciter case 114 is fixed between the first mirror plate 112 and the second mirror plate 113. The inside of the vibration exciter case 114 is filled with lubricating oil. A first holder 115 is attached to the first mirror plate 112, and a second holder 116 is attached to the second mirror plate 113. The first holder 115 is supported by a cylindrical housing 118 via a bearing 117. The housing 118 hangs down from the left side surface of the body frame 2, and its lower end is attached to the front wheel side plate SP1 located inside the roll 111 via vibration isolating rubber 121 and a support member 122.

[0044] The second holder 116 is fixed to the second end plate 113. The front wheel electric motor M1 is attached via a motor mounting plate 124 to the front wheel side plate SP2 which hangs down from the right side of the body frame 2 and has its lower end located at the roll 111. A reduction gear mechanism 125 is provided on the output portion M1a of the front wheel electric motor M1. The output portion M1a is connected to the second end plate 113 via vibration isolating rubber 123 and a support member 126. A cover 127 which covers the right end portion is attached to the second holder 116.

[0045] As a result, when the front wheel electric motor M1 rotates, the rotational force is reduced in speed by the reduction gear mechanism 125 and transmitted to the support member 126 and the second end plate 113, and the roll 111 runs and rotates while the first holder 115 is supported by the housing 118.

[0046] On the other hand, the vibration electric motor M4 is attached via a motor attachment plate 128 connected to the front wheel side plate SP1. A joint member (for example, a constant velocity joint) 129 connects the output shaft of the vibration electric motor M4 and a vibration generating shaft 130.

[0047] The vibration generating shaft 130 is disposed within the vibration generating case 114 and extends in the vehicle width direction around an axis that is coaxial with the roll 111. The vibration generating shaft 130 includes a main body 131, support shafts 132 and 133 disposed on both ends of the main body 131, and an eccentric weight 134. The main body 131 is a shaft-shaped portion, and support shafts 132 and 133 having a smaller diameter than the main body 131 are disposed on both ends. The support shaft 132 is supported by the first holder 115 via a bearing 135. The support shaft 133 is supported by the second holder 116 via a bearing 136. The eccentric weight 134 is disposed on the outer circumferential surface of the main body 131.

[0048] As described above, when the vibration electric motor M4 rotates, the rotational force is transmitted to the vibration shaft 130 via the joint member 129, and the vibration shaft 130 rotates relative to the first holder 115 and the second holder 116. At that time, since the vibration shaft 130 is provided with the eccentric weight 134, the roll 111 vibrates.

[0049] When the operator OP operates the vibration switch 39 (see FIG. 4), a vibration signal is output from the control unit 3 to the vibration inverter J4, and the vibration electric motor M4 operates based on the drive instruction value of the vibration inverter J4. Note that a new operation switch may be provided to provide, for example, a high vibration mode or a low vibration mode. When the vibration electric motor M4 is rotated at high speed, the vibration becomes large, and when it is rotated at low speed, the vibration becomes small. Also, the rotation speed of the vibration electric motor M4 may be freely controlled according to the operation of the operator OP, so that the strength of the vibration can be adjusted.

[0050] In this embodiment, the vibration generating shaft 130 (vibration system) is provided only on the front wheel R1, but it may also be provided on the rear wheel R2, or may be provided only on the rear wheel R2.

[0051] <Deceleration mechanism> As shown in Figures 14 to 18, the rotational forces of the right rear wheel electric motor M2 and the left rear wheel electric motor M3 are transmitted to the rear wheel R2 via a reduction mechanism. The reduction mechanism is made up of a first gear box 200A and a second gear box 200B, and is provided from the second rear space 16b of the rear space 16 to the rear wheel R2. As shown in Figure 14, the right rear wheel electric motor M2 and the left rear wheel electric motor M3 are arranged so that their output shafts face each other and are parallel to the vehicle width direction.

[0052] The first gear box 200A includes a first gear 201, a second gear 204, a third gear 205, and a fourth gear 207. The first gear box 200A is a box-shaped body having a rectangular parallelepiped shape and is disposed inside the second rear space 16b. The first gear 201, the second gear 204, the third gear 205, and the fourth gear 207 are all disposed with their rotation axes parallel to the vehicle width direction. The inside of the first gear box 200A is filled with lubricating oil.

[0053] The first gear 201 includes a shaft portion 201a and a gear portion 201b provided on the shaft portion 201a. Both ends of the shaft portion 201a are connected to output shafts of the electric motor M2 for the right rear wheel and the electric motor M3 for the left rear wheel, respectively, and are supported by bearings 202, 202 provided in the first gear box 200A.

[0054] The second gear 204 includes a shaft portion 204a, and a large diameter gear 204b and a small diameter gear 204c provided on the shaft portion 204a. Both ends of the shaft portion 204a are supported by bearings 203, 203 provided in the first gear box 200A. The large diameter gear 204b is meshed with a gear portion 201b of the first gear 201 and a gear portion 205b of the third gear 205, respectively. The small diameter gear 204c is meshed with a large diameter gear 207b of the fourth gear 207.

[0055] The third gear 205 includes a shaft portion 205a and a gear portion 205b provided on the shaft portion 205a. The shaft portion 205a is supported by a bearing 206 provided in the first gear box 200A. A non-excitation brake (negative brake) 62 is connected to the tip of the shaft portion 205a. In other words, the non-excitation brake 62 is connected to the outside of the first gear box 200A via the shaft portion 205a.

[0056] The fourth gear 207 includes a shaft portion 207a, and a large diameter gear 207b and a small diameter gear 207c provided on the shaft portion 207a. The shaft portion 207a communicates with the first gear box 200A and the second gear box 200B, and is supported by bearings 209, 209 provided on the second gear box 200B. A seal member 208 is interposed between the first gear box 200A and the outer periphery of the shaft portion 207a. The large diameter gear 207b is disposed in the first gear box 200A, and is engaged with the small diameter gear 204c of the second gear 204. The small diameter gear 207c is disposed in the second gear box 200B.

[0057] As shown in Fig. 17, the second gear box 200B is arranged in parallel with the first gear box 200A, and is a vertically long box-shaped body arranged from the second rear space 16b to the rear wheel R2. The fifth gear 210 includes a shaft portion 210a and a gear portion 210b provided on the shaft portion 210a. The shaft portion 210a is supported by a bearing 211 provided on the second gear box 200B. The gear portion 210b is engaged with the small diameter gear 207c of the fourth gear 207 and the gear portion 213b of the sixth gear 213, respectively.

[0058] The sixth gear 213 includes a shaft portion 213a and a gear portion 213b provided on the shaft portion 213a. The shaft portion 213a is a shaft extending across the tires R2A to R2D of the rear wheel R2. Holders 218A, 218B are provided below the second gear box 200B, extending left and right in the vehicle width direction and supporting the shaft portion 213a via a bearing 214. The left end of the shaft portion 213a is fastened to a hub 216A via a fastening portion 217A. The hub 216A also supports disc wheels DWA, DWB arranged inside the tires R2A, R2B.

[0059] Similarly, the right end of the shaft portion 213a is fastened to a hub 216B via a fastening portion 217B. The hub 216B supports the disc wheels DWC, DWD that are disposed inside the tires R2C, R2D.

[0060] In the reduction gear mechanism configured as described above, the rotational forces of the right rear wheel electric motor M2 and the left rear wheel electric motor M3 are transmitted to the shaft 213a via the first gear 201, the second gear 204, the fourth gear 207, the fifth gear 210 and the sixth gear 213, and are also transmitted to the rear wheel R2 via the hubs 216A, 216B.

[0061] <Steering system> Next, the steering system will be described. As shown in Fig. 19, the steering system includes an orbit roll 51, an electric hydraulic pump 52, a filter 53, an accumulator 54, hydraulic cylinders 55, 55, and a pressure switch 56 (see Fig. 4). In the steering system, these components are connected by piping to form a hydraulic circuit.

[0062] The orbit roll 51 is connected to the steering 19 and is disposed inside the dashboard 14. The electric hydraulic pump 52 is electrically connected to the 24V battery K2 and is disposed in the first rear space 16a. The filter 53 is connected to a part of the piping and is a member that removes impurities such as dust and iron contained in the hydraulic oil. The accumulator 54 is connected to a part of the piping and is a device that stores and releases the fluid energy of the hydraulic oil. The filter 53 and the accumulator 54 are disposed in the second rear space 16b. As shown in FIG. 20, the hydraulic cylinders 55, 55 are cylinders that connect the front frame 11 and the rear frame 12, and are disposed in pairs on both sides in the vehicle width direction. The extension and contraction of the hydraulic cylinders 55, 55 enables the vehicle to turn left and right.

[0063] 4, the pressure switch 56 checks the pressure in the hydraulic circuit and determines whether to start or stop the electric hydraulic pump 52. When the control unit 3 receives a detection signal from the pressure switch 56 and the pressure in the hydraulic circuit drops below a predetermined value, it starts the electric hydraulic pump 52, and when the pressure is equal to or greater than the predetermined value, it stops the electric hydraulic pump 52. The pressure switch 56 can also detect pressure errors in the hydraulic circuit.

[0064] The steering system includes an electric hydraulic pump 52, hydraulic cylinders 55, 55 driven by pressure oil discharged from the electric hydraulic pump 52, and a steering valve (not shown) that controls the direction and flow rate of the pressure oil supplied from the electric hydraulic pump 52 to the hydraulic cylinders 55, 55. The steering valve is switched according to the direction and amount of rotation of the steering wheel 19 to drive and control the hydraulic cylinders 55, 55. The switching of the steering valve according to the direction and amount of rotation of the steering wheel 19 is performed by the orbit roll 51.

[0065] <Brake system> In this embodiment, the following brake systems (1) to (3) are provided. Note that the types of brakes are not limited to those listed below, and may be increased or decreased as appropriate. (1) Neutral brake The neutral brake is a brake that is activated when the forward / reverse lever 17 is placed in the neutral position by the operator OP, as shown in Fig. 4. During stopping operation, the vehicle is decelerated by applying regenerative motion and reverse braking of the electric motor for the rolling wheels, and is stopped electrically by the zero rotation speed holding brake (excitation brake 61). The excitation brake 61 is a brake that is activated when energized and released when de-energized.

[0066] When the forward / reverse lever 17 is in the neutral position, the limit switch 32 outputs a detection signal to the control unit 3. The control unit 3 outputs a drive command value to the front wheel inverter J1, the right rear wheel inverter J2, and the left rear wheel inverter J3 so that the front wheel electric motor M1, the right rear wheel electric motor M2, and the left rear wheel electric motor M3 are each at 0 rotations. The control unit 3 also outputs a brake signal to the excitation brake 61. After a predetermined time has elapsed since the control unit 3 outputted the drive command value (maintaining 0 rotations) to each inverter J, the control unit 3 releases the brake of the excitation brake 61 while activating the non-excitation brake 62 (FIGS. 4 and 14) by the activation relay. The predetermined time can be set as appropriate. The non-excitation brake 62 is controlled by an activation relay connected to the control unit 3.

[0067] (2) Foot brake (emergency stop) The foot brake is a brake that is activated by depressing the brake pedal BP, as shown in Figures 4 and 8. When the operator OP depresses the brake pedal BP, a foot brake signal is output to the control unit 3. The control unit 3 then cuts off the power to each electric motor M. Furthermore, when the brake pedal BP is depressed, the base plate 22, which has been tilted by the mechanism in Figures 9 and 10 as described above, returns to the horizontal position. In other words, the shaft 21 (forward / reverse lever 17) is located in the neutral position, and the neutral brake described above is activated.

[0068] (3) Parking brake The parking brake is a brake that is activated by pressing the parking switch 37, as shown in Fig. 4. When the operator OP presses the parking switch 37, a parking brake signal is output to the control unit 3. The control unit 3 activates the non-excitation brake 62.

[0069] As shown in FIG. 16, the non-excitation brake 62 is a mechanical disk brake that operates when not energized. The non-excitation brake 62 is electrically connected to a 24V battery K2. When energized, the non-excitation brake 62 allows a rotor 64 to rotate in synchronization with the shaft portion 205a of the third gear 205. This allows the third gear 205 to rotate and allows the vehicle to travel. On the other hand, when not energized, the rotor 64 is clamped to prevent the shaft portion 205a from rotating, and the brake operates. The non-excitation brake 62 is provided with a release lever 63. The operator OP or a worker can release the non-excitation brake 62 by operating the release lever 63.

[0070] <Electrical system> As shown in Fig. 6, the battery K of this embodiment includes a 48V battery K1, a 24V battery K2, and a 12V battery K3. The 48V battery K1 and the 24V battery K2 are lithium ion batteries. A battery management unit (BMU) 71 is a device that measures the voltage value, current value, temperature, etc. of each battery cell and monitors and controls the battery (lithium ion secondary battery) K. The battery management unit 71 also has a function of displaying measured data, a balancing function of keeping the voltage between each cell constant, and a function of detecting overcharging and overdischarging. The battery management unit 71 and the control unit 3 are capable of communicating battery information via CAN communication.

[0071] The 12V battery K3 is a lead-acid battery. The 12V battery K3 is electrically connected to a starter switch 38 that starts the electric roller 1. The 12V battery K3 is also electrically connected to electrical equipment including lighting devices (e.g., hazard lamps) 40 and annunciators (e.g., a backup buzzer and an alert buzzer) 41. The 12V battery K3 can supply electricity to start (restart) the electric roller 1 and to various electrical equipment, even when the control unit 3 experiences a system downtime, for example.

[0072] The 48V battery K1 is electrically connected to each inverter J and each electric motor M. A DCDC converter 42 is interposed between the 48V battery K1 and the 12V battery K3. The DCDC converter 42 is a device for stepping down the voltage in order to supply power from the 48V battery K1 to the 12V battery K3. The 24V battery K2 is electrically connected to the electric hydraulic pump 52 and the non-excitation brake 62.

[0073] The control unit (VCU) 3 is a device that judges the state of the vehicle that changes while it is running and controls each part to maintain the optimum state. The control unit 3 controls each part that influences each other, such as the electric motor M, inverter J, and battery K, while taking into account the influence on other parts.

[0074] The control unit 3 includes a calculation unit (CPU: Central Processing Unit), a storage unit, a communication unit, etc. The control unit 3 may be located anywhere, but in this embodiment, it is attached to the front of a battery case KA (see FIG. 11) of the battery K. The calculation unit is a part that reads out a program stored in the storage unit and makes it function as a functional unit. The storage unit includes a RAM (Random Access Memory), a ROM (Read only memory), a HDD (Hard Disk Drive), etc. The storage unit stores various programs and drive instruction values ​​for each inverter J relative to the tilt angle of the potentiometer 31 as a drive instruction value file. The communication unit is, for example, a CAN communication unit, and is capable of communicating with each component.

[0075] The control unit 3 may also be linked to a Global Navigation Satellite System (GNSS) to acquire and utilize driving records, location information, driving conditions, and the like. The control unit 3 may also be linked to a compaction management device equipped with a sensor that acquires road surface compaction information to acquire and utilize compaction information in real time. The control unit 3 may also be linked to an autonomous driving device to enable autonomous driving by remote control. The control unit 3 may also transmit vehicle operation information (driving time, abnormality information, battery status, and the like) to a technical center, leasing company, and the like, and accumulate and manage the information.

[0076] <About action and effect> When the operator OP tilts the forward / reverse lever 17 forward, the vehicle moves forward, and when the operator tilts the lever backward, the vehicle moves backward. When the forward / reverse lever 17 is tilted, the potentiometer 31 outputs the tilt angle to the control unit 3. The control unit 3 outputs drive command values ​​to the front wheel inverter J1, the right rear wheel inverter J2, and the left rear wheel inverter J3, and operates the electric motors for the rolling wheels based on the drive command values. Increasing the tilt angle of the forward / reverse lever 17 makes the vehicle travel faster, and decreasing the tilt angle makes the vehicle travel slower. When the forward / reverse lever 17 is returned to the neutral position, the neutral brake is activated and the electric roller 1 stops.

[0077] When the operator OP operates the vibration switch 39, a vibration signal is output to the control unit 3. The control unit 3 transmits a vibration instruction value to the vibration inverter J4, and operates the vibration electric motor M4 based on the vibration instruction value. This causes the vibration shaft 130 to rotate, and the front wheel R1 to vibrate.

[0078] According to the electric roller 1 according to the present embodiment described above, fuel consumption and greenhouse gas emissions can be substantially eliminated by electrification. Furthermore, since noise can be reduced and greenhouse gas emissions can be substantially eliminated by electrification, the burden on the operator OP can be reduced and the working environment can be improved. Furthermore, since no hydraulic pump or hydraulic circuit for traveling is used as in the past, there is no need to replace hydraulic oil, and maintenance is easy.

[0079] Also, according to this embodiment, multiple electric motors for the rolling wheels (front wheel electric motor M1, rear right wheel electric motor M2, and rear left wheel electric motor M3) are provided. Although only one electric motor for the rolling wheels may be provided, providing multiple electric motors makes it possible to increase the main torque while preventing the electric motor for the rolling wheels from becoming too large. This makes it possible to stop and start on a hill.

[0080] Furthermore, according to this embodiment, the potentiometer 31 is provided, which enables fine speed control according to the inclination of the forward / reverse lever 17. Furthermore, the limit switch 32 is provided, which allows the neutral position to be detected reliably. Although the neutral position can be detected using only the potentiometer 31, if an error occurs in the input from the potentiometer 31, there is a risk that the vehicle will start moving even when the forward / reverse lever 17 is in the neutral position. However, according to this embodiment, the limit switch 32 is provided, which allows the neutral position to be detected reliably.

[0081] Furthermore, according to this embodiment, the vehicle is equipped with electrical equipment including lighting devices 40 and alarm devices 41, and is equipped with a plurality of batteries K with different voltages that are electrically connected to the electric motor for the rolling wheels and the electrical equipment, respectively. This makes it possible to supply power according to the voltage of each component. Furthermore, the 48V battery K1 and the 24V battery K2 are lithium-ion batteries (storage batteries), and therefore can be charged and used repeatedly.

[0082] Furthermore, according to this embodiment, the battery K is installed in the front space 15 of the body frame 2, and thus the size can be reduced by effectively utilizing the space. In other words, the battery K can be installed in the area where the engine was previously installed. Furthermore, the battery K can be protected by storing the battery K in a battery case KA. The battery K may be installed only in the rear space 16, or in both the front space 15 and the rear space 16.

[0083] According to this embodiment, the electrical equipment including the lighting device 40 and the alarm device 41 are electrically connected to the 12V battery K3, which is a lead-acid battery. This allows the electrical equipment including the lighting device 40 to function when the control unit 3 goes down. Therefore, even if the system goes down, an alert can be issued to the surroundings, and the vehicle can be smoothly restarted or reactivated.

[0084] Furthermore, according to this embodiment, the speedometer can be displayed on the display 18 provided on the dashboard 14, and vehicle information held by the control unit 3 can be displayed on the display 18. This allows the operator OP to grasp not only the speed, but also vehicle information held by the control unit 3, such as whether the vehicle is moving forward or backward, the presence or absence of vibration, the charge amount, the time, and the total mileage.

[0085] In addition, a mechanism for vibrating the rolling wheels may be provided as necessary, but according to this embodiment, the vibration generating shaft 130 is operated by a vibration inverter J4 and a vibration electric motor M4. This makes it easy to control the vibration of the vibration generating shaft 130, and by electrifying the vibration generating shaft 130, fuel consumption and greenhouse gas emissions can be substantially eliminated. Furthermore, by electrifying the vibration generating shaft 130, noise can be reduced and greenhouse gas emissions can be substantially eliminated, reducing the burden on the operator OP and improving the working environment. Furthermore, since a hydraulic pump or hydraulic circuit for vibration is not used as in the conventional system, there is no need to replace hydraulic oil, and maintenance is easy.

[0086] Furthermore, according to this embodiment, the vibration electric motor M4 is disposed on the sprung part (above the vibration isolating rubber 121 (toward the vehicle body frame 2)), so that the vibration acting on the vibration electric motor M4 can be reduced. Furthermore, by providing a constant velocity joint that connects the vibration generating shaft 130 and the output shaft of the vibration electric motor M4, the drive of the vibration electric motor M4 can be transmitted to the vibration generating shaft 130 even when the operating angle is provided.

[0087] Furthermore, according to this embodiment, since the electric hydraulic pump 52 is used in the steering system, fuel consumption and greenhouse gas emissions can be substantially eliminated by electrification. Furthermore, since the noise can be reduced and greenhouse gas emissions can be substantially eliminated by electrification, the burden on the operator OP can be reduced and the working environment can be improved. Furthermore, according to this embodiment, since the hydraulic cylinder 55 is driven by the electric hydraulic pump 52, changes to the mechanism around the steering can be kept to a minimum when electrification is performed.

[0088] Furthermore, according to this embodiment, pressure can be accumulated in the accumulator 54, which makes it possible to prevent the electric hydraulic pump 52 from seizing due to continuous operation, and also to reduce energy consumption.

[0089] Furthermore, according to this embodiment, the electric hydraulic pump 52, piping, and accumulator 54 are installed in the rear space 16 of the body frame 2, so that the rear space 16 can be utilized effectively and the number of pipes etc. spanning between the front space 15 and the rear space 16 can be reduced.

[0090] Furthermore, according to this embodiment, the hydraulic cylinders 55 are installed on both the left and right sides of the body frame 2, so that the difference in the amount of oil discharged in the left and right directions during turning can be reduced or eliminated, thereby stabilizing the behavior during turning. The number of hydraulic cylinders 55 may be just one on the body frame 2. This allows the structure to be simplified and the number of parts to be reduced.

[0091] According to this embodiment, when the forward / reverse lever 17 is in the neutral position, the control unit 3 outputs a zero rotation signal to the roller wheel inverters (front wheel inverter J1, rear right wheel inverter J2, rear left wheel inverter J3) and activates the excitation brake 61. This allows the brake system to be easily configured, and the electrification of the brake system can substantially eliminate fuel consumption and greenhouse gas emissions. Furthermore, the electrification can reduce noise and substantially eliminate greenhouse gas emissions, reducing the burden on the operator OP and improving the work environment. Furthermore, since a hydraulic circuit is not used in the brake system as in the past, there is no need to replace hydraulic oil, and maintenance is excellent.

[0092] Furthermore, according to this embodiment, the control unit 3 activates the non-excited brake 62, which mechanically brakes the motor, after a predetermined time has elapsed since the activation of the excited brake 61. Activating the excited brake 61 results in continued consumption of power during a stop, but according to this embodiment, the control unit 3 switches to the non-excited brake 62 after a predetermined time has elapsed and the brake of the excited brake 61 is released, thereby reducing power consumption.

[0093] In addition, when the operator OP depresses the brake pedal BP or operates a switch (parking switch 37) provided on the dashboard 14 or the driver's seat 13, the control unit 3 activates a non-excited brake 62 that mechanically applies brakes via an operating relay. This allows the vehicle to be stopped in an emergency.

[0094] Furthermore, by providing a release lever 63 for releasing the non-excitation brake 62 around the driver's seat 13, the operation of releasing the non-excitation brake 62 can be easily performed.

[0095] [Second embodiment: Mechanism for preventing over-rotation of electric motor for rolling wheels] Next, a second embodiment of the present invention will be described. The electric roller 1 according to the second embodiment differs from the first embodiment in that it is equipped with an over-rotation prevention mechanism that prevents over-rotation of the front wheel electric motor M1, the right rear wheel electric motor M2, and the left rear wheel electric motor M3 (electric motor for rolling wheels). In the second embodiment, the differences from the first embodiment will be mainly described. Note that the drive instruction values ​​and times shown below are merely examples, and these numerical values ​​can be set as appropriate.

[0096] <Challenges> As described above, the tilt of the forward / reverse lever 17 of the electric roller 1 is input to the control unit 3, which outputs a drive command value for acceleration, deceleration, or stop to each inverter J. Each inverter J that receives the drive command value from the control unit 3 controls the running operation of the vehicle by outputting a drive command value for the number of rotations to the electric motor for the rolling wheels to accelerate or decelerate according to the input amount of the forward / reverse lever 17.

[0097] However, the above-described embodiment has a problem in that the vehicle behavior is unstable when accelerating, decelerating, or stopping. For example, when the forward / reverse lever 17 is operated at full throttle in the forward direction during acceleration, the drive command value input to the inverter J rises in one go from 0 rotations to the target drive command value. At this time, the output of the electric motor for the rolling wheels is small, so the inertial force generated during acceleration cannot be suppressed. As a result, the rotation speed of the electric motor for the rolling wheels exceeds the target drive command value due to the inertia that cannot be controlled.

[0098] On the other hand, when decelerating or stopping, the electric motor for the roller wheels is controlled to apply regenerative motion and reverse braking to decelerate. When the forward / reverse lever 17 is returned from full throttle to the neutral position when decelerating or stopping, the drive command value output to the electric motor for the roller wheels drops to 0 RPM in one go. The braking torque generated at this time cannot be fully controlled due to insufficient output from the electric motor for the roller wheels, so a return swing occurs for the amount of braking torque that cannot be fully controlled when the vehicle is stopped.

[0099] These problems will be described in more detail. Fig. 21 is a graph showing the relationship between time and rotation speed in a comparative example at start-up. As shown in Fig. 21, the thin line shows the input of the forward / reverse lever 17. The forward / reverse lever 17 is, for example, in a state where it is tilted to the maximum in the forward or reverse direction (full throttle state).

[0100] The dotted line indicates the drive command value of the electric motor for the roller wheels in the comparative example. In other words, it is the drive command value output from the control unit 3 to the inverter for the roller wheels. In the comparative example shown in FIG. 21, the target drive command value P1 is about 2200 rpm. The time when the forward / reverse lever 17 is input is set as the "acceleration side command start point W1", the point at which the drive command value of the electric motor for the roller wheels reaches the target drive command value P1 (the point reached in calculation) is set as the "acceleration side target rotation speed arrival point N1", and the line connecting the acceleration side command start point W1 and the acceleration side target rotation speed arrival point N1 is set as the "first stage acceleration Q1". In the comparative example, for example, it is set to reach from 0 rpm to 2200 rpm in about 3.0 seconds.

[0101] The thick line indicates the rotation speed (actual rotation speed) of the electric motor for the rolling wheels in the comparative example. The rotation speed of the electric motor for the rolling wheels in the comparative example is lower than the first stage acceleration Q1, which is the drive command value, immediately after the acceleration side command start point W1. On the other hand, after reaching the acceleration side target rotation speed arrival point N1, the inertial force generated during acceleration cannot be suppressed, so the rotation speed of the electric motor for the rolling wheels exceeds the target drive command value P1 for a certain time. Furthermore, after slightly falling below the target drive command value P1, the rotation speed of the electric motor for the rolling wheels and the target drive command value P1 match. That is, in this comparative example, after the acceleration side target rotation speed arrival point N1, the electric motor for the rolling wheels becomes in an overspeed state for a certain time, and the vehicle behavior becomes unstable.

[0102] FIG. 22 is a graph showing the relationship between time and the number of revolutions in the comparative example when the vehicle is stopped. As shown in FIG. 22, the target drive command value P2 is 0 rpm (0 revolutions) on the stopped side. The point at which the forward / reverse lever 17 is returned from the full throttle state to the neutral position is defined as the "deceleration side command start point W2", the point at which the drive command value of the electric motor for the rolling wheels reaches the target drive command value P2 (the point that is reached in calculation) is defined as the "deceleration side target revolutions arrival point N2", and the straight line connecting the deceleration side command start point W2 and the deceleration side target revolutions arrival point N2 is defined as the "first stage deceleration Q2". In the comparative example, for example, the setting is such that the speed is set to reach from 2200 rpm to 0 rpm in about 2.0 seconds.

[0103] The rotation speed of the electric motor for the compaction wheels in the comparative example exceeds the drive command value immediately after the deceleration side command start point W2. On the other hand, after the deceleration side target rotation speed reach point N2 is reached, the generated braking torque cannot be fully controlled due to insufficient output of the electric motor for the compaction wheels, so the rotation speed of the electric motor for the compaction wheels falls below the target drive command value P2 for a certain time. Thereafter, the rotation speed of the electric motor for the compaction wheels and the target drive command value P2 match. In other words, in this comparative example, the electric motor for the compaction wheels is in an overspeed state for a certain time after the deceleration side target rotation speed reach point N2, so the vehicle behavior becomes unstable (swing back movement when stopped).

[0104] <Configuration of the over-rotation prevention mechanism for the electric motor for rolling wheels - Starting side> 23 is a graph showing the drive command value of the electric motor for the rolling wheel of the comparative example and the embodiment as a relationship between time and the number of revolutions. The solid line shows the drive command value of the electric motor for the rolling wheel of the embodiment. The dotted line shows the drive command value of the electric motor for the rolling wheel of the comparative example.

[0105] As shown by the solid line in Fig. 23, at the start of the embodiment, the drive command value of the electric motor for the rolling wheels has an acceleration side shift point U1, and also has a first stage acceleration Q3 and a second stage acceleration Q4. The slope (acceleration) of the first stage acceleration Q3 is larger (steeper) than the slope (acceleration) of the first stage acceleration Q1 of the comparative example. On the other hand, the slope of the second stage acceleration Q4 is smaller (gentler) than the slope of the first stage acceleration Q1 of the comparative example.

[0106] Fig. 24 is a graph showing the relationship between time and rotation speed at start-up in an embodiment. In Fig. 24, the dotted line shows the drive command value of the electric motor for the rolling wheels in the embodiment. The solid line shows the rotation speed of the electric motor for the rolling wheels in the embodiment. In the embodiment as well, the drive command value of the electric motor for the rolling wheels is set so that the target drive command value P1 is 2200 rpm and the target drive command value P1 is reached 3.0 seconds after the input of the forward / reverse lever 17.

[0107] As shown in FIG. 24, at the start of the embodiment, the slope of the second stage acceleration Q4 when approaching the acceleration side target rotation speed reaching point N1 is smaller (gentler angle) than the slope of the first stage acceleration Q1 of the comparative example. More specifically, at the start of the embodiment, the slope of the first stage acceleration Q3 is larger than the slope of the first stage acceleration Q1 (see FIG. 23) of the comparative example, so the rotation speed of the electric motor for the rolling wheels rises more rapidly than in the comparative example. Thereafter, the target drive command value P1 is reached more gently in the second stage acceleration Q4 than in the comparative example. This allows the electric motor for the rolling wheels to reach the target drive command value P1 without over-rotating (or by reducing the over-rotation). Therefore, the vehicle behavior during acceleration can be stabilized.

[0108] <Configuration of the over-rotation prevention mechanism for the electric motor for rolling wheels - Stop side> As shown by the solid line in Fig. 23, on the stopping side of the embodiment, the drive command value of the electric motor for the rolling wheels is provided with a deceleration side shift point U2, and a first stage deceleration Q5 and a second stage deceleration Q6 are provided. The slope (deceleration) of the first stage deceleration Q5 is larger (steeper angle) than the slope (deceleration) of the first stage deceleration Q2 of the comparative example. On the other hand, the slope of the second stage deceleration Q6 is smaller (gentler angle) than the slope of the first stage deceleration Q2 of the comparative example.

[0109] Fig. 25 is a graph showing the relationship between time and rotation speed in an embodiment when stopped. In Fig. 25, the dotted line shows the drive command value of the electric motor for the rolling wheels in the embodiment. The solid line shows the rotation speed of the electric motor for the rolling wheels in the embodiment. In the embodiment, the target drive command value P2 is set to 0 rpm, and is set to reach the target drive command value P2 2.0 seconds after the forward / reverse lever 17 returns to the neutral position.

[0110] As shown in FIG. 25, when the vehicle is stopped in the embodiment, the slope of the second-stage deceleration Q6 when approaching the deceleration-side target rotation speed reaching point N2 is smaller (gentler angle) than the slope of the first-stage deceleration Q2 in the comparative example. More specifically, when the vehicle is stopped in the embodiment, the slope of the first-stage deceleration Q5 is larger than the slope of the first-stage deceleration Q2 (see FIG. 23) in the comparative example, so that the rotation speed of the electric motor for the rolling wheels drops more rapidly than in the comparative example. After that, the target drive command value P2 is reached more gently at the second-stage deceleration Q6. This allows the electric motor for the rolling wheels to reach the target drive command value P2 without over-rotating (or by reducing the over-rotation). This prevents swinging back during deceleration and stabilizes the vehicle behavior.

[0111] FIG. 26 is a graph showing the drive command value of the electric motor for the rolling wheel of the modified example in terms of time and rotation speed. As shown in FIG. 26, in the modified example, acceleration or deceleration is performed in three stages. As shown by the solid line in FIG. 26, the drive command value of the electric motor for the rolling wheel on the starting side according to the modified example includes shift points U3 and U4, as well as a first stage acceleration Q11, a second stage acceleration Q12, and a third stage acceleration Q13. The third stage acceleration Q13 faces the acceleration side target rotation speed arrival point N1. The slope of the third stage acceleration Q13 is smaller (gentler angle) than the first stage acceleration Q1 of the comparative example. This makes it possible to prevent over-rotation of the electric motor for the rolling wheel, as in the second embodiment.

[0112] As shown by the solid line in FIG. 26, the drive command value of the electric motor for the rolling wheel on the stop side according to the modified example includes shift points U5 and U6, as well as a first stage reduction Q14, a second stage reduction Q15, and a third stage reduction Q16. The third stage reduction Q16 faces the reduction side target rotation speed reaching point N2. The slope of the third stage reduction Q16 is smaller (gentler angle) than the first stage reduction Q2 of the comparative example. This makes it possible to prevent over-rotation of the electric motor for the rolling wheel, as in the second embodiment. As in the modified example, two or more shift points may be provided on the start side or the stop side.

[0113] As described above, the over-rotation prevention mechanism for the electric motor for the rolling wheels has at least one speed change point in the drive command value for the electric motor for the rolling wheels, and sets the gradient toward the acceleration side target speed reaching point N1 and the deceleration side target speed reaching point N2 to be smaller than the gradient in the comparative example. This allows signals to be output to the inverter for the rolling wheels in multiple stages of speed change ranges, making it possible to gradually reach the target speed of the electric motor for the rolling wheels.

[0114] In the overspeed prevention mechanism of the electric motor for the rolling wheel of this embodiment, when setting the inclination of the acceleration side target rotation speed arrival point N1 and the deceleration side target rotation speed arrival point N2 in the drive command value, a reference inclination (here, the inclination of the first stage acceleration Q1 and the first stage deceleration Q2 in the comparative example) is set from the acceleration side target rotation speed arrival point N1 and the deceleration side target rotation speed arrival point N2, and the inclination is set so as to be smaller (so as to have a gentler angle) than the inclination. The drive command value of the overspeed prevention mechanism of the electric motor for the rolling wheel may be set based on a drive command value file that is preset according to the tilt angle of the forward / reverse lever 17. The drive command value file is, for example, a data file in which a shift point is preset according to the tilt angle of the forward / reverse lever 17, the target drive command value, the arrival time, etc. The drive command value file is stored in the storage unit of the control unit 3. In addition, the drive command value of the overspeed prevention mechanism of the electric motor for the rolling wheel may be calculated by the control unit 3 from the detected tilt angle of the forward / reverse lever 17, and calculated appropriately.

[0115] [Third embodiment: Mechanism for preventing over-rotation of electric motor for vibration] Next, a third embodiment of the present invention will be described. The electric roller 1 according to the third embodiment differs from the first embodiment in that it is provided with an over-rotation prevention mechanism for the vibrating electric motor that prevents over-rotation of the vibrating electric motor M4 in the vibration system. In the third embodiment, the differences from the first embodiment will be mainly described.

[0116] <Challenges> As in the second embodiment, the vibration electric motor M4 also has an eccentric weight 134 on the vibration generating shaft 130, and therefore may over-revolve relative to the target drive command value when starting and stopping vibration. This causes the vehicle behavior to become unstable, giving the operator OP a sense of discomfort.

[0117] <Configuration of the over-rotation prevention mechanism for the vibration electric motor> The mechanism for preventing over-rotation of the vibration electric motor provides a speed change point in the drive command value output from the control unit 3 to the vibration inverter J4. The method of setting the speed change point is the same as in the second embodiment, so a detailed description will be omitted. The control unit 3 outputs a signal to the vibration inverter J4 in multiple stages of speed change ranges during vibration generation, so that the vibration electric motor M4 gradually reaches the target rotation speed. As a result, the vibration electric motor M4 gradually reaches the target rotation speed, and therefore unstable vibration behavior caused by over-rotation can be suppressed.

[0118] In addition, when vibration is stopped, the control unit 3 outputs a signal to the vibration inverter J4 in a multiple-stage speed range to stop the vibration gradually. This suppresses the swing-back phenomenon of the vibration excitation shaft 130, and allows the vibration excitation shaft 130 to be stopped stably.

[0119] [Fourth embodiment, front wheel dashboard] Next, an electric roller 1D according to a fourth embodiment of the present invention will be described. This embodiment differs from the first embodiment mainly in the structure of the front wheels R1D, the structure of the dashboard 14D, and the inclination management unit 301. In this embodiment, the differences from the first embodiment will be mainly described.

[0120] As shown in FIG. 27, the front wheel R1D is equipped with a roll 111D, and a front wheel electric motor M1 and a vibration electric motor M4 are installed at both ends of the width direction of the vehicle. The front wheel R1D has a longer roll 111D and a shorter vibration shaft 130 than the structure of the first embodiment described above. As a result, each part including the front wheel electric motor M1 and the vibration electric motor M4 is stored inside the roll 111D. Therefore, when performing a rolling operation, the roll 111D can be moved as close as possible to other structures, etc., thereby improving operability. Other structures of the front wheel R1D are generally the same as those of the first embodiment, and therefore the same reference numerals as those of the first embodiment are used and the description is omitted.

[0121] Furthermore, as shown in Figures 28 and 29, in addition to the structure of the first embodiment, the electric roller 1D is equipped with a water sprinkler switch 81 for sprinkling water, a liquid agent switch 82 for spraying liquid agent, a vibration H / L switch 83 for changing the vibration frequency, a speed change switch 84 for changing the vehicle speed, a hazard switch (light switch) 85, a buzzer switch (alarm switch) 86, and a headlight switch (light switch) 87.

[0122] As shown in FIG. 29, a water sprinkler switch 81, a liquid agent switch 82, a vibration H / L switch 83, a gear shift switch 84, a hazard switch 85, a buzzer switch 86, a headlight switch 87, a parking switch 37 and a vibration switch 39 are provided on the upper surface of the dashboard 14D around a display (e.g., an LCD display) 18.

[0123] The water sprinkling switch 81 is electrically connected to the control unit 3D and is a switch that controls the water sprinkling unit (not shown) to start or stop water sprinkling. When the water sprinkling switch 81 is turned ON, water is sprinkled onto the roll 111D via the control unit 3D and the water sprinkling unit (not shown), and when the water sprinkling switch 81 is turned OFF, water sprinkling stops.

[0124] The liquid agent switch 82 is electrically connected to the control unit 3D and is a switch that starts or stops the spraying of the liquid agent via a liquid agent spraying unit (not shown). When the liquid agent switch 82 is turned ON, the liquid agent is sprayed onto the roll 111D via the control unit 3D and the liquid agent spraying unit (not shown), and when the liquid agent switch 82 is turned OFF, the spraying of the liquid agent is stopped.

[0125] The vibration H / L switch 83 is electrically connected to the control unit 3D, operates in conjunction with the vibration switch 39, and is a switch for selecting a high-speed vibration mode or a low-speed vibration mode. The high-speed vibration mode is a mode in which the vibration electric motor M4 rotates at high speed to increase the vibratory force, and the low-speed vibration mode is a mode in which the vibration electric motor M4 rotates at low speed to decrease the vibratory force. When the vibration H / L switch 83 is set to the high-speed vibration mode side, a high-speed vibration mode signal is sent to the vibration inverter J4. On the other hand, when the vibration H / L switch 83 is set to the low-speed vibration mode side, a low-speed vibration mode signal is sent to the vibration inverter J4.

[0126] The speed change switch 84 is electrically connected to the control unit 3D and is a switch for changing the speed of the vehicle. In the first embodiment, two speeds could be selected with the traveling H / L switch 36, but in this embodiment, a multi-speed structure with three or more speeds is adopted.

[0127] The hazard switch 85 is a switch that turns the hazard warning lamps on or off. The buzzer switch 86 is a switch that turns the alarm 41 that outputs an alarm sound on or off. The headlight switch 87 is a switch that turns the headlights on or off. For the headlights, high beam or low beam can be selected. The hazard switch 85, buzzer switch 86, and headlight switch 87 are also electrically connected to the control unit 3D, and each operation can be controlled and managed.

[0128] The operating status of each switch may be displayed at any time on the display 18. In the first embodiment described above, the electric hydraulic pump 52 is powered by the 24V battery K2, but it may be powered by the 48V battery K1 as in this embodiment shown in Figs.

[0129] [Fourth embodiment control mode] Next, a control mode related to the running state of an electric roller 1D according to a fourth embodiment of the present invention will be described. As shown in Fig. 30, the electric roller 1D has a terminal 91 electrically connected to a 48V battery K1 and a 24V battery K2 (hereinafter also referred to as "batteries K1, K2"). In addition, a charging battery K4 is electrically connected to a terminal 92. The charging battery K4 is for charging the batteries K1, K2 by connecting the terminals 91, 92.

[0130] The electric roller 1D (control unit 3D) of this embodiment has five basic modes, namely, "switch off mode," "standby mode," "ready mode," "run mode," and "charging mode," as well as "torque up mode" and "charging while running mode," as control modes related to the running state of the electric roller 1D.

[0131] These modes can be switched by the operator OP through operation of a starter switch 38 (number of times, time, etc.) or a predetermined input operation (including operation of the starter switch 38). The starter switch 38 corresponds to a key cylinder that is operated by inserting an ignition key in a vehicle powered by an internal combustion engine, i.e., an engine vehicle. The control unit 3D can, for example, display these modes (excluding the switch-off mode) on the display 18. This allows the operator OP to understand the state (mode) of the vehicle.

[0132] <Switch off mode> The control unit 3D is in the switch-off mode when the starter switch 38 is in the switch-off state. The switch-off mode corresponds to a state in which the ignition key is removed from the key cylinder in an engine vehicle. In the switch-off mode, the power is turned off (the control unit (VCU) 3D is not started either), so the electric roller 1D is unable to run. The energy consumption in the switch-off mode (the power consumption of the 48V battery K1 and the 24V battery K2) is zero. In the switch-off mode, the forward / reverse lever 17 is set to the neutral position by the operation of the operator OP, and the parking switch 37 is set to ON by the operation of the operator OP (i.e., the parking brake is activated).

[0133] <Standby mode> The control unit 3D goes into the standby mode when the starter switch 38 is input from the switch-off mode. The standby mode is a mode in which the vehicle is in a standby state before traveling. The standby mode corresponds to a state in which the main switch is turned on and power can be supplied to electrical equipment (such as a display) in an engine vehicle by turning the ignition key one step while it is inserted in the key cylinder. In the standby mode, the control unit 3D is started by power being supplied from the 12V battery K3 (lead storage battery), but the control unit 3D does not start the inverter J (the inverter for the rolling wheels), so the electric roller 1D is in a state in which it cannot travel. The energy consumption in the standby mode (the power consumption of the 48V battery K1 and the 24V battery K2) is zero. Note that the ready mode described later may be designed to automatically switch to the standby mode under a predetermined condition (for example, when no operation is performed for a long time during the ready mode). Details of the specification will be described later.

[0134] <Ready mode> The control unit 3D goes from standby mode to ready mode by the operator OP operating the starter switch 38 (number of times, time, etc.) or by a specified input operation. The ready mode corresponds to a state in an engine vehicle where the engine is started by turning the ignition key one step further from the standby state. In other words, in the ready mode, the inverter J is started under the control of the control unit 3D (the forward / reverse lever 17 is in the neutral position), and the electric roller 1D is in a state where it can run. The amount of energy consumed in the ready mode (the amount of power consumed by the 48V battery K1 and the 24V battery K2) is very small.

[0135] <Run mode> The control unit 3D switches from the ready mode to the run mode when the forward / reverse lever 17 is operated and set to the forward position or the reverse position. In other words, the run mode is a mode that switches by tilting the forward / reverse lever 17 and puts the vehicle in a traveling state. The electric motor M is driven by tilting the forward / reverse lever 17, and when the torque of the electric motor M exceeds a predetermined value, the parking brake (non-excited brake 62) is automatically released and the electric roller 1D starts traveling. The energy consumption (power consumption of the 48V battery K1 and the 24V battery K2) in the run mode varies depending on the traveling speed, traveling distance, etc. Note that the electric roller 1D may start traveling by tilting the forward / reverse lever 17 after the operator OP manually releases the parking brake.

[0136] <Charging mode (normal charging mode)> The control unit 3D switches from the switch-off mode to the charging mode in response to a predetermined input operation by the operator OP (for example, connection of charging terminals 91, 92 (charging cables)) while in the switch-off mode. In the charging mode, the control unit 3D executes charging by allowing charging of the 48V battery K1 and the 24V battery K2 from the charging battery K4 as a charging power source. Here, the charging battery K4 may be an external power source or a battery that can be loaded on the electric roller 1D. Details of the charging mode (normal charging mode) will be described later.

[0137] <Torque up mode> When a predetermined input operation is performed in the ready mode, the control unit 3D switches from the ready mode to the torque-up mode. In the torque-up mode, the control unit 3D temporarily increases the torque output upper limit value of the inverter J (the inverter for the rolling wheels).

[0138] <Charging mode while driving> When a predetermined input operation is performed in the ready mode, the control unit 3D switches from the ready mode to the in-travel charging mode. In the in-travel charging mode, the control unit 3D allows charging of the 48V battery K1 and the 24V battery K2 from the charging battery K4 while the vehicle is traveling. Here, the charging battery K4 can be loaded on the electric roller 1D and does not interfere with the traveling of the electric roller 1D. In the in-travel charging mode, the control unit 3D can cause the vehicle to travel when the forward / reverse lever 17 is operated and set to the forward position or the reverse position. Also, in the in-travel charging mode, the control unit 3D drives the electric motor M to make the electric roller 1D in a travel-enabled state. When the charging rates of the 48V battery K1 and the 24V battery K2 in the charging mode during travel are equal to or higher than a predetermined charging rate (for example, full charge (SoC: 100%)) or when a predetermined input operation (disconnection of the charging terminals 91, 92 (charging cables)) is performed, the control unit 3D ends the charging mode during travel and switches from the charging mode during travel to a ready mode or a simple run mode. Here, the control unit 3D can obtain the charging rates of the 48V battery K1 and the 24V battery K2 detected and calculated by the BMU 71 and use them for the determination. Details of the charging mode during travel will be described later.

[0139] <Example of operation: Auto standby control> Next, the operation of the auto-standby control that automatically switches from the ready mode to the standby mode will be described. As shown in Fig. 31, in this operation example, the control unit 3D determines whether or not the vehicle is in the ready mode in step S41, and determines the state of the parking switch 37 (i.e., the state of the parking brake) in step S42. The control unit 3D also determines the state of the forward / reverse lever 17 in step S43, and determines whether a predetermined time has elapsed in the ready mode, with the parking switch 37 OFF (the parking brake released), and the forward / reverse lever 17 in the neutral position in step S44.

[0140] In the ready mode (Yes in step S41), when the parking switch 37 is OFF (Yes in step S42) and the forward / reverse lever 17 is in the neutral position (Yes in step S43) for a predetermined time (Yes in step S44), the control unit 3D switches from the ready mode to the standby mode (step S45). In addition, in the ready mode (Yes in step S41), when the parking switch 37 is OFF (Yes in step S42) and the forward / reverse lever 17 is operated to the forward position or reverse position (No in step S43) before the predetermined time has elapsed (No in step S44), the control unit 3D switches from the ready mode to the run mode (step S46).

[0141] This flow ends if, in the ready mode state (Yes in step S41), the parking switch 37 is OFF (Yes in step S42) and the forward / reverse lever 17 is in the neutral position (Yes in step S43) for a predetermined time (No in step S44), the ready mode is no longer set (No in step S41) or the parking switch 37 is turned ON (the parking brake is applied) (No in step S42).

[0142] <Example of operation: Normal charging> Next, the operation of normal charging will be described. As shown in Fig. 32, in this operation example, the control unit 3D determines whether the terminals 91, 92 are connected or not in step S51, and determines whether the switch-off mode is set or not in step S52. The control unit 3D also determines whether the charging rates of the batteries K1, K2 are equal to or higher than a predetermined value in step S55, and determines whether the terminals 91, 92 are connected or not in step S56.

[0143] When the control unit 3D detects a connection between the terminals 91, 92 (Yes in step S51) and is in the switch-off mode (Yes in step S52), it switches from the switch-off mode to the charging mode to permit charging and starts charging the batteries K1, K2 from the charging battery K4 (step S53). On the other hand, when the control unit 3D detects a connection between the terminals 91, 92 (Yes in step S51) but is not in the charging mode (and is not in the charging-while-driving mode) (No in step S52), it rejects charging and causes the alarm 41 to emit an error sound (step S54).

[0144] After step S53 is executed, if the charging rates (SoC: State of Charge) of the batteries K1, K2 are less than a predetermined value (e.g., 100%) (No in step S55) and the terminals 91, 92 are connected (No in step S56), the flow returns to step S55, and the control unit 3D continues charging the batteries K1, K2. On the other hand, after step S53 is executed, if the charging rates of the batteries K1, K2 are equal to or greater than a predetermined value (e.g., 100%) (Yes in step S55), the control unit 3D ends charging the batteries K1, K2 (step S57) and switches from the charging mode to the switch-off mode (step S58). Furthermore, after executing step S53, if the control unit 3D detects that the terminals 91, 92 have been disconnected (Yes in step S56) even if the charging rate of the batteries K1, K2 is less than a predetermined value (e.g., 100%) (No in step S55), it terminates charging the batteries K1, K2 (step S57) and switches from the charging mode to the switch-off mode (step S58).

[0145] <Example of operation: Starting charging mode while driving> The operation of the in-travel charging mode (at the start) will be described. As shown in Fig. 33, in this operation example, the control unit 3D determines whether or not the vehicle is in the ready mode in step S61, and determines whether or not a predetermined input operation has been performed in step S62. The control unit 3D also determines the state of the forward / reverse lever 17 in step S63, and determines the state of the parking switch 37 (i.e., the state of the parking brake) in step S64.

[0146] In the ready mode (Yes in step S61), when the control unit 3D detects that a specific input operation (e.g., a specific switch is turned ON) has been performed (Yes in step S62), the forward / reverse lever 17 is in the neutral position (Yes in step S63), and the parking switch 37 is ON (the parking brake is applied) (Yes in step S64), the control unit 3D switches from the ready mode to the charging mode while traveling (step S65). Next, the control unit 3D causes the display 18 to display that the charging mode is while traveling (step S66).

[0147] If the control unit 3D is not in ready mode (No in step S61), does not detect that a specified input operation has been performed (No in step S62), the forward / reverse lever 17 is in the forward or reverse position (No in step S63), or the parking switch 37 is OFF (the parking brake is released) (No in step S64), it does not switch to charging mode while driving and repeats the judgments of steps S61 to S64.

[0148] In addition, in the charging mode while traveling, the control unit 3D can drive the vehicle when the forward / reverse lever 17 is in the forward or reverse position. In the charging mode while traveling, the control unit 3D can stop the vehicle when the forward / reverse lever 17 is in the neutral position (and the parking switch 37 is ON (the parking brake is applied)).

[0149] <Example of operation: Charging while driving> The operation of the in-travel charging mode (charging while traveling) will be described. As shown in Fig. 34, in this operation example, the control unit 3D determines whether the terminals 91, 92 are connected or not in step S71, and determines whether the in-travel charging mode is in step S72. The control unit 3D also determines whether the charging rates of the batteries K1, K2 are equal to or higher than a predetermined value in step S75, and determines whether the terminals 91, 92 are connected or not in step S76.

[0150] When the control unit 3D detects a connection between the terminals 91, 92 (Yes in step S71) and is in the charging mode while traveling (Yes in step S72), it allows charging and starts charging the batteries K1, K2 from the charging battery K4 (step S73). On the other hand, when the control unit 3D detects a connection between the terminals 91, 92 (Yes in step S71) but is not in the charging mode while traveling (and is not in the charging mode) (No in step S72), it denies charging and causes the alarm 41 to emit an error sound (step S74).

[0151] After step S73 is executed, if the charging rate (SoC: State of Charge) of the batteries K1, K2 is less than a predetermined value (e.g., 100%) (No in step S75) and the terminals 91, 92 are connected (No in step S76), the flow returns to step S75, and the control unit 3D continues charging the batteries K1, K2. On the other hand, after step S73 is executed, if the charging rate of the batteries K1, K2 is equal to or greater than a predetermined value (e.g., 100%) (Yes in step S75), the control unit 3D ends the charging of the batteries K1, K2 (step S77). Also, after step S73 is executed, if the charging rate of the batteries K1, K2 is less than a predetermined value (e.g., 100%) (No in step S75) and the control unit 3D detects the disconnection of the terminals 91, 92 (Yes in step S76), the control unit 3D ends the charging of the batteries K1, K2 (step S77).

[0152] <Example of operation: Ending charging mode while driving> The operation of the in-travel charging mode (at the end) will now be described. As shown in Fig. 35, in this operation example, the control unit 3D determines in step S81 whether charging has ended, and determines in step S82 whether a predetermined continuous period of time has passed without charging after the connection of the terminals 91, 92. Furthermore, the control unit 3D determines the state of the forward / reverse lever 17 in step S83, and determines the state of the parking switch 37 (that is, the state of the parking brake) in step S84.

[0153] When charging is completed in the above-mentioned step S77 (Yes in step S81), if the forward / reverse lever 17 is in the neutral position (Yes in step S83) and the parking switch 37 is ON (the parking brake is applied) (Yes in step S84), the control unit 3D switches from the charging mode during travel to the ready mode (step S85). Even when charging is not completed (No in step S81), if the batteries K1 and K2 are not charged for a predetermined time (Yes in step S82), the control unit 3D switches from the charging mode during travel to the ready mode (step S85) if the forward / reverse lever 17 is in the neutral position (Yes in step S83) and the parking switch 37 is ON (the parking brake is applied) (Yes in step S84). After executing step S85, the control unit 3D stops displaying the charging mode during travel on the display 18 (step S87).

[0154] If the forward / reverse lever 17 is not in the neutral position (No in step S83), the control unit 3D switches from the charging mode during travel to the run mode (step S86). After executing step S86, the control unit 3D stops displaying on the display 18 that the charging mode is during travel (step S87).

[0155] According to the electric roller 1D of the present embodiment described above, fuel consumption and greenhouse gas emissions can be substantially eliminated by electrification. Furthermore, since noise can be reduced and greenhouse gas emissions can be substantially eliminated by electrification, the burden on the operator OP can be reduced and the working environment can be improved. Furthermore, there is no need to change hydraulic oil, and maintenance is excellent. Furthermore, the inclusion of an inverter for the rolling wheels allows for easy speed control.

[0156] Furthermore, according to this embodiment, if the parking brake is released during the ready mode and the forward / reverse lever 17 remains in the neutral position for a predetermined time, the mode automatically switches to the standby mode in which power consumption is zero, thereby reducing power consumption and improving the operating time of the battery K. Furthermore, according to this embodiment, the mode automatically switches to the standby mode in which driving is not possible under the above-mentioned predetermined conditions, thereby preventing the vehicle from moving unintentionally due to an erroneous operation by the operator OP.

[0157] Furthermore, according to the electric roller 1D of this embodiment, the predetermined time can be set according to the skill of the operator OP, so that it is possible to achieve both ease of operation and reduction in power consumption.

[0158] Although the embodiment of the present invention has been described above, appropriate design changes are possible without departing from the spirit of the present invention. [Explanation of symbols]

[0159] 1 Electric roller 2 Body frame 3. Control Unit (VCU) 11 Front Frame 12 Rear Frame 17 Forward / reverse lever 18 Display 19 Steering 51 Orbit Roll 52 Electric hydraulic pump 53 Filters 54 Accumulator 55 Hydraulic Cylinder 61 Electromagnetic Brake 62 Non-excitation brake 63 Release lever 71 Battery Management Unit (BMU) J Inverter K Battery K1 48V battery K2 24V battery K3 12V Battery K4 Rechargeable battery (charging power source) M Electric motor R1 Front wheel R2 rear wheel

Claims

1. A pair of rolling wheels are installed at the front and rear, A vehicle body frame that rotatably supports the rolling wheels; An electric motor for driving the rolling wheels; A roller wheel inverter that controls the rotation speed of the electric motor for the roller wheel; A battery that supplies power to the electric motor for rolling wheels and the inverter for rolling wheels; A control unit that outputs a signal to the inverter for the rolling wheels in accordance with the inclination of the forward / reverse lever, The vehicle does not have an internal combustion engine, and the power source of the rolling wheel is the battery alone; The control unit is a standby mode in which the control unit is activated and the inverter for the rolling wheels is not activated, a ready mode in which the control unit and the inverter for the rolling wheels are activated and the forward / reverse lever is in a neutral position, so that the vehicle can run; and a run mode in which the electric motor for the rolling wheels is driven and the vehicle can run because the forward / reverse lever is in a forward position or a reverse position, An electric roller characterized in that, when the parking brake is released during the ready mode and the forward / reverse lever is kept in a neutral position for a predetermined period of time, the electric roller switches to the standby mode.

2. 2. The electric roller according to claim 1, wherein the control unit is capable of arbitrarily setting the predetermined time.

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