JP2017109552A - Vehicular braking device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vehicular braking device capable of suitably outputting a braking start signal.SOLUTION: A dump truck 1 comprises an electric brake and a cooperation brake having higher braking characteristics than that of the electric brake. A contact possibility determination controller 34 which determines a possibility of contacting an obstacle determines whether to start braking by the electric brake on the basis of braking characteristics of the electric brake, and obstacle information and vehicle information, and outputs a first braking start signal when determining that the braking should be started. Further, the contact possibility determination controller 34 determines whether to start braking by the cooperation brake on the basis of the braking characteristics of the electric brake, and obstacle information and vehicle information, and outputs a second braking start signal when determining that the braking should be started. The contact possibility determination controller 34 makes signal output timing of outputting the first braking start signal earlier when a travel speed of the dump truck 1 is in a low speed range.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a vehicle braking device used for a vehicle such as a dump truck.

  In general, a dump truck as a representative example of a large transport vehicle is used to transport crushed stones or earth and sand mined in an open-pit mining site or mine. The dump truck employs, for example, an electric drive system in which wheels are driven by an electric motor for traveling as a driving system for traveling. In this case, the dump truck can apply, as a brake (braking mechanism) that applies a braking force, for example, an electric brake that uses a regenerative torque generated by power generation of a traveling electric motor as a braking force, and a braking force that is greater than that of the electric brake. A friction type mechanical brake (for example, a dry type single plate disc brake, a wet type multi plate disc brake) is mounted.

  For this reason, two brake pedals are provided in front of the driver's seat where the operator of the dump truck is seated, one on each of the left and right sides of the rotation axis of the steering wheel. For example, the first brake pedal disposed on the right side (between the rotation axis and the accelerator pedal) corresponds to a brake pedal for applying a braking force by an electric brake. The first brake pedal (electric brake brake pedal) is used, for example, to stop the vehicle at normal times (depressed).

  On the other hand, the second brake pedal arranged on the left side is a brake pedal for applying a braking force (a braking force of both the electric brake and the mechanical brake) by a cooperative brake in which the electric brake and the mechanical brake are coordinated. Correspond. The second brake pedal (brake pedal for cooperative braking) is used (depressed) when, for example, the vehicle is urgently stopped (emergency stop).

  Here, in the mechanical brake, the disk rotor and / or the friction pad, which are the friction engagement portions, are easily worn. For this reason, for example, when the operation of the cooperative brake is unnecessarily performed due to a delay in the operation timing of the electric brake (cooperative brake is frequently used), the cost increases due to the replacement of the disk rotor and / or the friction pad, There is a possibility of lowering the conveyance efficiency (operation efficiency).

  On the other hand, Patent Document 1 describes a technology of an automatic braking control device mounted on a vehicle such as a truck or a bus. This automatic braking control device is configured to provide an auxiliary brake prior to applying a large braking force when automatically applying a braking force to avoid contact (collision) with an object existing in the traveling direction of the vehicle. Is configured to apply a smaller braking force.

JP 2007-223582 A

  By the way, in order to avoid the vehicle from coming into contact with obstacles around the vehicle (for example, other vehicles, buildings, rocks, people, and other objects that should not be in contact with the vehicle) It is possible to do. That is, an obstacle in the traveling direction of the vehicle is detected, the possibility of contact with the obstacle is determined, and when it is determined that the possibility of contact is high, the operator is alerted and / or the automatic brake is controlled. It is conceivable to adopt a configuration for performing the above. At this time, in the case of a vehicle equipped with two brakes having different braking characteristics (braking performance, braking force, braking distance), for example, two types of brakes, that is, an electric brake and a cooperative brake, the braking of the electric brake should be started. It is conceivable that two commands, that is, a command (braking start command) and a command (braking start command) to start the braking of the cooperative brake are output.

  In this case, since the braking characteristics of the cooperative brake are higher than the braking characteristics of the electric brake (the braking performance is high), if the possibility of contact with an obstacle is determined from the braking characteristics of the two types of brakes, respectively, The braking start command for the electric brake is output prior to the braking start command. However, the difference between the braking characteristics of the two types of brakes is large in the high speed range, for example, but is small in the low speed range. For this reason, in the low speed range, there is a possibility that the time from when the braking start command for the electric brake is output until the braking start command for the cooperative brake is output may be shortened.

  For example, in the case of a configuration that issues an alarm to the operator (outputs a warning) by outputting a braking start command, an electric brake alarm is issued, and the operator depresses the brake pedal of the electric brake based on the alarm Immediately after, there is a possibility that a warning for cooperative braking is issued. At this time, the operator's operation of the brake pedal does not catch up with the alarm, and for example, the brake pedal depression operation may be delayed. On the other hand, in the case of a configuration in which automatic braking is controlled by outputting a braking start command, there is a possibility that braking of the cooperative brake is performed immediately after braking of the electric brake. As a result, coordinated braking is frequently used, which may lead to an increase in costs due to the replacement of the disk rotor and / or friction pad, and a decrease in conveying efficiency.

  An object of the present invention is to provide a vehicle braking device that can appropriately output a braking start command.

  The vehicle braking device according to the present invention has a first brake for applying a first braking force to the vehicle, a braking characteristic higher than that of the first brake, and applies a second braking force to the vehicle. A second brake, an obstacle information detecting device for detecting obstacle information including information on a distance between the obstacle present around the vehicle and the vehicle, and a vehicle including information on a traveling speed of the vehicle A vehicle information detecting device for detecting information; and when the vehicle is running, braking by the first brake is performed based on the braking characteristics of the first brake, the obstacle information, and the vehicle information. A first braking command output unit that determines whether or not to start and outputs a first braking start signal when it is determined that braking by the first brake should be started; and the vehicle travels. When the second brake is When it is determined whether braking by the second brake should be started based on dynamic characteristics, the obstacle information, and the vehicle information, and when it is determined that braking by the second brake should be started And a second braking command output unit for outputting a second braking start signal.

  In order to solve the above-described problem, a feature of the configuration adopted by the present invention is that the first braking command output unit outputs the first braking start signal when the traveling speed of the vehicle is in a low speed range. The configuration is such that the output timing of the output signal is made earlier.

  Further, in order to solve the above-described problem, a feature of the configuration adopted by the present invention is that the first braking command output unit is configured such that the first braking command output unit is configured such that the traveling speed of the vehicle is higher than the low speed range. The first braking start signal is not output when the traveling speed of the vehicle is in a low speed range, and the second braking command output unit is configured to output the entire traveling speed of the vehicle. In the region, the second braking start signal is output.

  The vehicle braking apparatus according to the present invention can appropriately output a braking start command (braking start signal).

The front view which shows the dump truck by which the vehicle braking device by embodiment is mounted. The whole block diagram which shows the dump truck in FIG. Sectional drawing seen from the arrow III-III direction in FIG. 1 which shows the rear-wheel and disc brake of a dump truck. The block diagram which shows the millimeter wave radar, obstruction detection apparatus, and vehicle body controller in FIG. The characteristic line figure which shows an example of the relationship between the speed of the vehicle by 1st Embodiment, and the braking distance of an electric brake and a cooperative brake. The characteristic diagram which shows an example of the relationship between the speed of the vehicle by the comparative example, and the braking distance of an electric brake and a cooperative brake. The characteristic line figure which shows an example of the relationship between the speed of the vehicle by 2nd Embodiment, and the braking distance of an electric brake and a cooperative brake. The characteristic line figure which shows an example of the relationship between the speed of the vehicle by 3rd Embodiment, and the braking distance of an electric brake and a cooperative brake. The characteristic line figure which shows an example of the relationship between the speed of the vehicle by 4th Embodiment, and the braking distance of an electric brake and a cooperative brake. The block diagram which shows the millimeter wave radar by 5th Embodiment, an obstruction detection apparatus, and a vehicle body controller.

  Hereinafter, a vehicle braking device according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings, taking as an example a case where the vehicle braking device is applied to a dump truck.

  1 to 5 show a first embodiment. In FIG. 1, a dump truck 1 which is a large vehicle (transportation vehicle) transports transported materials such as crushed stones or earth and sand mined in an open-pit mining site, a mine or the like. The dump truck 1 includes a front wheel 2 and a rear wheel 3 that are wheels, a vehicle body 4 that has a sturdy frame structure and can be driven by the front wheel 2 and the rear wheel 3, and a rear end side on the vehicle body 4 as a fulcrum. And a vessel 5 as a loading platform provided so as to be able to tilt (raise and lower).

  The left and right front wheels 2 are rotatably provided on the front side of the vehicle body 4. The front wheel 2 constitutes a steered wheel that is steered (steered) by an operator of the dump truck 1. As with the rear wheel 3, the front wheel 2 is formed with a tire diameter (outer diameter dimension) of, for example, 2 to 4 meters. Between the front part of the vehicle body 4 and the front wheel 2, a front suspension 6 made of, for example, a hydraulic shock absorber or the like is provided. The front suspension 6 suspends the front side of the vehicle body 4 from the front wheel 2.

  The left and right rear wheels 3 are rotatably provided on the rear side of the vehicle body 4. The rear wheel 3 constitutes a drive wheel of the dump truck 1 and is rotationally driven by an electric motor 14 for traveling described later. Between the rear wheel 3 and the rear part of the vehicle body 4, a rear suspension 7 made of, for example, a hydraulic shock absorber is provided. The rear suspension 7 suspends the rear side of the vehicle body 4 from the rear wheel 3.

  The vessel 5 is formed as a large container having a total length of 10 to 13 m (meters) in order to load a large amount of loads such as crushed stones or earth and sand (hereinafter referred to as earth and sand 8). The rear bottom portion of the vessel 5 is connected (supported) to the rear end side of the vehicle body 4 via a connecting pin 9 so as to be tiltable (rotatable). On the other hand, on the upper front side of the vessel 5, a flange portion 5 </ b> A that covers a cab 11 described later from above is integrally provided. The eaves part 5A has, for example, a function of protecting the cab 11 from stepping stones and a function of protecting the cab 11 when the vehicle (dump truck 1) falls.

  The front side of the vessel 5 (the flange portion 5A side) is connected to a connecting pin by extending or reducing a pair of left and right hoist cylinders 10 (only one shown) provided between the vessel 5 and the vehicle body 4 so as to be stretchable. 9 is moved up and down with the position of 9 as a fulcrum. Thereby, the vessel 5 is rotated between a transport position (traveling position) where the front side of the vessel 5 shown in FIG. 1 is lowered and a discharge position (not shown) where the front side of the vessel 5 is raised. The For example, at the discharge position, a large amount of earth and sand 8 loaded on the vessel 5 is discharged to a predetermined unloading site so as to slide down from the vessel 5 inclined backward.

  The cab 11 is provided on the front side of the vehicle body 4 so as to be located below the flange portion 5 </ b> A of the vessel 5. That is, the cab 11 is disposed on the deck portion 4 </ b> A that is located on the front side of the vehicle body 4 and is a flat floor plate. The cab 11 forms a driver's cab in which an operator (driver) of the dump truck 1 gets on and off, and a driver's seat, a start switch (start switch), an accelerator pedal, and an electric brake brake as a first brake pedal. A pedal, a brake pedal for cooperative braking as a second brake pedal, a parking brake switch, a steering wheel for steering, and a plurality of operation levers (all not shown) are provided.

  Here, for example, the brake pedal for electric brake is disposed on the right side of the rotation axis of the steering wheel in front of the driver's seat (more specifically, between the rotation axis and the accelerator pedal). The brake pedal for electric brake is depressed by an operator when applying braking force by the electric brake. The electric brake is a brake that uses the regenerative torque generated by the electric power generated by the traveling electric motor 14 as a braking force, and is used, for example, for stopping the vehicle at normal times.

  On the other hand, the brake pedal for cooperative brake is disposed, for example, on the left side of the rotation axis of the steering wheel in front of the driver's seat. The brake pedal for cooperative brake is stepped on by an operator when applying a braking force by a cooperative brake in which an electric brake and a mechanical brake are coordinated. The mechanical brake is a friction type brake that can apply a braking force larger than that of the electric brake, and can be constituted by, for example, a dry type disc brake and / or a wet multi-disc disc brake. In the embodiment, the mechanical brake is constituted by a disk brake 24 described later.

  The cooperative brake is a brake that applies both the braking force of the electric brake (braking force by the electric motor 14) and the mechanical brake (braking force by the disc brake 24), and for example, for stopping the vehicle in an emergency (emergency stop). Used. The disc brake 24, which is a mechanical brake, is used together with an electric brake as a cooperative brake, and is used alone, for example, for applying a parking brake. That is, when the parking brake switch is operated to the braking application side (ON side), the braking force by the mechanical brake (disc brake 24) is applied.

  The engine 12 is located on the lower side of the cab 11 and is provided on the vehicle body 4. The engine 12 is configured by, for example, a large diesel engine. As shown in FIG. 2, the engine 12 drives a generator (alternator) 13 to generate three-phase AC power (for example, about 1500 kW). Further, the engine 12 rotationally drives a hydraulic pump (not shown) serving as a hydraulic source. The hydraulic pump supplies pressure oil to the hoist cylinder 10 and a steering cylinder (not shown) for power steering.

  The left and right electric motors 14 are electric motors for traveling, and are provided below the rear part of the vehicle body 4. The electric motor 14 is configured by a large electric motor including, for example, a three-phase induction motor, a three-phase brushless DC motor, or the like. The electric motor 14 is rotationally driven by electric power supplied from the generator 13 via the motor control device 15. As shown in FIG. 2, the electric motor 14 is provided on each of the left and right sides of the vehicle body 4 to rotate the left and right rear wheels 3 independently of each other.

  The electric motor 14 is connected (coupled) to the rear wheel 3 via a speed reduction mechanism (not shown) such as a planetary gear speed reduction mechanism. The electric motors 14 are driven to rotate independently by the motor control device 15. The motor control device 15 is configured by a power distribution control panel or the like that is located on the side of the cab 11 and is erected on the deck portion 4A of the vehicle body 4. A control signal from the vehicle body controller 16 is input to the motor control device 15.

  The motor control device 15 makes the rotational speeds of the left and right rear wheels 3 the same, for example, when the vehicle goes straight, based on the control signal from the vehicle body controller 16, or the left and right rear wheels 3 according to the turning direction when turning. Controls such as changing the rotation speed. Further, when the electric brake brake pedal or the cooperative brake brake pedal is depressed, the motor control device 15 applies the regenerative torque generated by the electric motor 14 as a braking force based on a control signal from the vehicle body controller 16. To do. At this time, the generated power (regenerative power) is consumed as heat by a resistor (resistor) (not shown), for example.

  The vehicle body controller 16 includes a microcomputer or the like, and controls the operation of the vehicle (dump truck 1). For example, the vehicle body controller 16 controls the drive of the left and right electric motors 14 by controlling the motor control device 15 in accordance with the operation of an accelerator pedal, an electric brake brake pedal, and a cooperative brake brake pedal. As shown in FIG. 2, the input side of the vehicle body controller 16 is an accelerator operation sensor 17, an electric brake operation amount sensor 18, a cooperative brake operation switch 19, a wheel speed sensor 20, a steering sensor 21, a load sensor 22, and a gradient sensor 23. The output side is connected to the motor control device 15, an obstacle detection device 33 described later, and the like.

  The accelerator operation sensor 17 is provided on the accelerator pedal. The accelerator operation sensor 17 detects an operator's accelerator operation amount (pedal operation amount) and outputs a detection signal to the vehicle body controller 16. The electric brake operation amount sensor 18 is provided on an electric brake brake pedal. The electric brake operation amount sensor 18 detects an electric brake operation amount (pedal operation amount) of the operator and outputs a detection signal to the vehicle body controller 16. The cooperative brake operation switch 19 is provided on the brake pedal for cooperative brake. The cooperative brake operation switch 19 detects the presence or absence of the cooperative brake operation by the operator (ON / OFF of the pedal) and outputs a detection signal to the vehicle body controller 16.

  The wheel speed sensor 20 is provided in the vehicle body 4 in the vicinity of the front wheel 2 and / or the rear wheel 3. The wheel speed sensor 20 detects the rotation speed (wheel speed) of the front wheel 2 and / or the rear wheel 3 and outputs a detection signal to the vehicle body controller 16. The steering sensor 21 is provided in the vicinity of the front wheel 2 serving as a steering wheel or a steering wheel. The steering sensor 21 detects the rotation angle of the steering wheel or the steering angle of the front wheel 2 and outputs a detection signal to the vehicle body controller 16. The vehicle body controller 16 estimates (calculates) the steering direction of the dump truck from the rotation angle or the steering angle.

  The load sensor 22 is provided on the rear suspension 7, for example. The load sensor 22 detects the cylinder pressure of the rear suspension 7 and outputs a detection signal to the vehicle body controller 16. The vehicle body controller 16 estimates the weight of the load (loading amount, loading load) from the cylinder pressure. The gradient sensor 23 is provided, for example, on the vehicle body 4. The gradient sensor 23 is constituted by a gravity sensor (acceleration sensor), and outputs a detection signal to the vehicle body controller 16. The vehicle body controller 16 estimates the gradient of the road surface on which the dump truck 1 is stopped or traveling (the inclination of the vehicle body 4) from the detection value of the gravity sensor.

  The vehicle body controller 16 constitutes a vehicle information detection device that detects vehicle information (vehicle body information) including information on the traveling speed (corresponding to the wheel speed) of the vehicle (dump truck 1) together with the wheel speed sensor 20 and the like. . More specifically, the vehicle body controller 16, together with the electric brake operation amount sensor 18, the cooperative brake operation switch 19, the wheel speed sensor 20, the steering sensor 21, the load sensor 22, and the gradient sensor 23, information on vehicle braking (electric brake A vehicle information detection device for detecting vehicle operation information, cooperative brake operation information), wheel speed information, vehicle steering direction information, vehicle load (loading amount) information, and vehicle gradient information. It is composed.

  Next, the disc brake 24, which is a mechanical brake, will be described with reference to FIGS.

  As shown in FIG. 2, the disc brakes 24 are provided on the left and right front wheels 2 and the left and right rear wheels 3, respectively. The disc brake 24 includes a disc rotor 24A that rotates together with the front wheel 2 or the rear wheel 3 that is a wheel, and a cylinder (not shown) that is disposed across the outer periphery of the disc rotor 24A and that faces the disc rotor 24A. A caliper 24B, a piston (not shown) slidably inserted into a cylinder of the caliper 24B, and a pair of friction pads 24C (see FIG. 3) pressed against the disc rotor 24A by the pistons. It is comprised including.

  Here, the disc brake 24 on the rear wheel 3 side will be described with reference to FIG. As shown in FIG. 3, the rear wheel 3 includes a hub 3A, a rim 3B, and a tire 3C. The hub 3A is rotatably supported by a shaft 4B provided on the vehicle body 4 via a bearing 25. A cylindrical rim 3B is provided on the outer peripheral side of the hub 3A, and a tire 3C is attached to the outer peripheral side of the rim 3B.

  The traveling electric motor 14 is connected to the hub 3A via a reduction mechanism (not shown), and the hub 3A is rotationally driven by the electric motor 14. A disk rotor 24A is fixed to the hub 3A. On the other hand, a caliper 24B is fixed to the shaft 4B on the vehicle body 4 side via a brake support member 4C. When brake fluid pressure is supplied to the cylinder of the caliper 24B, the piston is slidably displaced in the cylinder toward the disc rotor 24A. As a result, the friction pad 24C is pressed against both surfaces of the disk rotor 24A, and braking force is applied to the wheels (front wheel 2, rear wheel 3) that rotate integrally with the disk rotor 24A.

  Next, the vehicle braking device 31 mounted on the dump truck 1 will be described with reference to FIG. 4 in addition to FIGS.

  The vehicle braking device 31 includes a millimeter wave radar 32, an obstacle detection, in addition to the electric motor 14 and the disc brake 24 that apply braking force to the vehicle (dump truck 1), and a vehicle information detection device that detects vehicle information. The apparatus 33 is comprised.

  The electric motor 14 corresponds to a first brake that applies a first braking force to the vehicle. Further, the electric motor 14 and the disc brake 24 constituting the cooperative brake correspond to a second brake that applies a second braking force to the vehicle. The second brake has a higher braking characteristic than the first brake. Specifically, the braking force (second braking force) by the second brake is larger than the braking force (first braking force) by the first brake (second braking force> first braking force). ). In other words, the braking distance (second braking distance) by the second brake is shorter than the braking distance (first braking distance) by the first brake (second braking distance <first braking distance). ).

  The vehicle information detection device detects vehicle information including information on the traveling speed of the vehicle (corresponding to wheel speed), and may be configured by, for example, a vehicle body controller 16 and various sensors connected to the vehicle body controller 16. it can. As various sensors, in addition to the wheel speed sensor 20, various state quantities (vehicle information) of the vehicle such as an electric brake operation amount sensor 18, a cooperative brake operation switch 19, a steering sensor 21, a load sensor 22, a gradient sensor 23, etc. A sensor (detector) to detect is mentioned. The vehicle body controller 16 is connected to the contact possibility determination controller 34 of the obstacle detection device 33. The vehicle body controller 16 includes information on the operation of the electric brake, information on whether or not the cooperative brake is operated, information on the wheel speed corresponding to the traveling speed of the vehicle, information on the steering direction of the vehicle, information on the load of the vehicle, and the vehicle is The gradient information is output as vehicle information (vehicle information) to the vehicle body determination unit 35 of the contact possibility determination controller 34.

  The millimeter wave radar 32 as an obstacle information detection device detects obstacle information including information on the distance between an obstacle present around the vehicle and the vehicle. The millimeter wave radar 32 serves as an external recognition sensor, and measures the position of an object around the vehicle, that is, the position of an obstacle that should not contact the vehicle, such as another vehicle, a building, a rock, or a person. is there. In addition to the millimeter wave radar 32, the external field recognition sensor is, for example, a radar such as a laser radar or an infrared radar (for example, a light emitting element such as a semiconductor laser and a light receiving element that receives the light), and / or a stereo camera, a single A camera such as a camera (for example, a digital camera) can be used.

  The millimeter wave radar 32 emits radio waves around the vehicle (for example, the traveling direction of the vehicle, the front of the vehicle), and detects the radio waves that are reflected and returned from obstacles existing around the vehicle. The millimeter wave radar detects an obstacle around the vehicle based on the reflected radio wave, attaches an ID (identification number) to the obstacle, and determines the distance between the obstacle and the vehicle. Measure (calculate) the relative speed between the obstacle and the vehicle. The millimeter wave radar 32 can handle information on a plurality of obstacles by attaching different IDs to the detected obstacles.

  The millimeter wave radar 32 is connected to a contact possibility determination controller 34 of the obstacle detection device 33. The millimeter wave radar 32 uses, for example, the information on the distance between the obstacle and the vehicle and the information on the relative speed between the obstacle and the vehicle along with the detected obstacle ID to the contact possibility determination controller 34. The information is output to the obstacle determination unit 36 as obstacle information.

  As shown in FIG. 4, the obstacle detection device 33 includes a contact possibility determination controller 34 made of a microcomputer or the like, and a monitor device 38 as a notification device. The obstacle detection device 33 determines the possibility of contact between the vehicle and the obstacle by the contact possibility determination controller 34. When the possibility of contact is determined to be high, the obstacle detection device 33 performs braking by the electric brake from the monitor device 38. A warning (electric brake warning) and / or a warning (cooperative brake warning) that triggers braking by the cooperative brake are issued.

  The contact possibility determination controller 34 determines the possibility of contact between the vehicle and the obstacle. The input side of the contact possibility determination controller 34 is connected to the millimeter wave radar 32 and the vehicle body controller 16, and the output side thereof is connected to the monitor device 38. When the vehicle is traveling, the contact possibility determination controller 34 starts braking by the electric brake based on the braking characteristics (braking performance) of the electric brake (first brake), the obstacle information, and the vehicle information. The first braking command output unit outputs a first braking start signal to the monitor device 38 when it is determined whether or not braking should be started by the electric brake. Further, the contact possibility determination controller 34 performs braking by the cooperative brake based on the braking characteristic (braking performance) of the cooperative brake (second brake), the obstacle information, and the vehicle information when the vehicle is traveling. And a second braking command output unit that outputs a second braking start signal to the monitoring device 38 when it is determined that braking by cooperative braking should be started. .

  For this reason, the contact possibility determination controller 34 includes a vehicle body determination unit 35, an obstacle determination unit 36, and a contact possibility determination unit 37. The vehicle body determination unit 35 is connected to the vehicle body controller 16. Vehicle information (vehicle information) is input from the vehicle controller 16 to the vehicle body determination unit 35. That is, the vehicle body determination unit 35 receives, for example, information on the operation of the electric brake (operation amount), information on the presence / absence of operation of the cooperative brake (ON / OFF), wheel speed information (rotation speed), Information on the steering direction of the vehicle (steering angle), information on the load of the vehicle (weight), and information on the gradient at which the vehicle is located (angle) are input. Information on the operation of the electric brake corresponds to the operation amount of the brake pedal for the electric brake. Information on the presence / absence of cooperative brake operation corresponds to the presence / absence (ON / OFF) of an electric brake brake pedal operation.

  The vehicle body determination unit 35 calculates (calculates) parameters necessary for determining the possibility of contact with an obstacle from the vehicle information. For example, the vehicle body determination unit 35 calculates a vehicle speed (vehicle body speed) that is a traveling speed (vehicle speed) of the vehicle from the wheel speed, and calculates a course of the vehicle from the wheel speed and the steering direction. In addition, the vehicle body determination unit 35 calculates the braking performance (braking distance) of the electric brake and the braking performance (braking distance) of the cooperative brake from the wheel speed, the load (loading amount, load) and the gradient. Specifically, braking performance (braking characteristics) serving as a reference that is set in advance, for example, braking performance (braking characteristics) of an electric brake when the load is maximum on a flat dry road surface (gradient 0), and braking of a cooperative brake The performance (braking characteristics) is adjusted (corrected) according to the load capacity and the gradient at that time, and the braking performance (braking distance) corresponding to the wheel speed (vehicle speed) at that time from the corrected braking performance (braking characteristics). ) Is calculated.

  The obstacle determination unit 36 is connected to the millimeter wave radar 32. Further, the obstacle determination unit 36 is connected to the vehicle body determination unit 35. Obstacle information is input from the millimeter wave radar 32 to the obstacle determination unit 36. That is, the obstacle determination unit 36 receives, for example, the ID of the detected obstacle (s) from the millimeter wave radar 32, the distance between the obstacle and the vehicle corresponding to the ID, and the obstacle. The relative speed between the vehicle and the vehicle is input. Further, the vehicle speed (vehicle speed) that is the traveling speed of the vehicle is input to the obstacle determination unit 36 from the vehicle body determination unit 35.

  The obstacle determination unit 36 converts the relative speed of the obstacle into a speed. Further, the obstacle determination unit 36 determines the possibility of contact such as the obstacle data determined as noise and the obstacle data with a low possibility of contact among the measurement data (obstacle information) of the millimeter wave radar 32. Data unnecessary for determination is removed (erased).

  The contact possibility determination unit 37 is connected to the vehicle body determination unit 35 and the obstacle determination unit 36. For example, the vehicle speed (vehicle speed), the course of the vehicle, the braking performance of the electric brake, and the braking performance of the cooperative brake are input to the contact possibility determination unit 37 from the vehicle body determination unit 35. The contact possibility determination unit 37 receives, for example, the obstacle ID and the obstacle speed from the obstacle determination unit 36.

  The contact possibility determination unit 37 determines whether or not an obstacle is contacted from the course of the vehicle, the possibility of contact with the obstacle when braking by the electric brake is started, and braking by the cooperative brake. Determine the possibility of contact with an obstacle when starting. The possibility of contact with an obstacle (contact possibility) is determined, for example, by taking into consideration the delay time of the system and the time delay related to the operation in addition to the limit time of contact avoidance based on the braking performance.

  If it is determined that the braking by the electric brake should be started by the determination of the contact possibility, the contact possibility determination unit 37 outputs a first braking start signal to the monitor device 38 (first braking start). Command flag rises). Further, when it is determined by the determination of contact possibility that braking by cooperative braking should be started, a second braking start signal is output from the contact possibility determination unit 37 to the monitor device 38 (second The brake start command flag rises). The first braking start signal is a command to issue an alarm (electric brake alarm) for alerting braking by the electric brake from the monitor device 38, that is, that the operator should start to depress the brake pedal for electric brake. It becomes a command for informing. The second braking start signal is a command to issue an alarm (electric brake alarm) for alerting braking by the cooperative brake from the monitor device 38, that is, the operator should start the depression operation of the brake pedal for the cooperative brake. It becomes a command for informing.

  The monitor device 38 is provided near the driver's seat in the cab 11. The monitor device 38 issues an alarm (electric brake alarm) that triggers braking by an electric brake and an alarm (cooperative brake alarm) that triggers braking by a cooperative brake. The monitor device 38 includes, for example, a monitor (display screen) that serves as a display device and an acoustic device that outputs sound. The monitor device 38 is connected to the contact possibility determination unit 37.

  When the first braking start signal is input from the contact possibility determination unit 37, the monitor device 38 issues an electric brake alarm. For example, the monitor device 38 outputs a buzzer, a sound or the like from the sound device and / or informs the display device of that in order to prompt the operator to start the depression operation of the brake pedal for electric brake. indicate. In addition, when the second braking start signal is input from the contact possibility determination unit 37, the monitoring device 38 issues a cooperative brake warning. For example, the monitor device 38 outputs a buzzer, a sound or the like from the acoustic device and / or informs the display device so as to prompt the operator to start the depression operation of the brake pedal for cooperative braking. indicate.

  When the electric brake alarm is issued from the monitoring device 38, the operator can step on the electric brake brake pedal and avoid contact between the dump truck 1 and the obstacle. Further, when the cooperative brake alarm is issued from the monitor device 38, the operator can step on the cooperative brake brake pedal and avoid contact between the dump truck 1 and the obstacle.

  FIG. 6 shows an example of braking characteristics (relationship between speed and braking distance) of the electric brake and the cooperative brake according to the comparative example. The braking characteristics of the electric brake and the cooperative brake shown in FIG. 6 correspond to the reference (standard) braking characteristics, that is, the actual (original) braking characteristics. For example, the braking characteristics in FIG. 6 correspond to the actual braking characteristics of the electric brake and the cooperative brake in a predetermined environment (standard environment, reference environment) set in advance. The predetermined environment is, for example, a reference environment, that is, a predetermined temperature (for example, standard temperature), a predetermined road surface (for example, a dry road surface, an unpaved road surface, a flat road surface), or a predetermined load (for example, maximum load). It can be. The actual braking characteristics of the electric brake and the cooperative brake in a predetermined environment vary depending on, for example, the type, specification, and model of the dump truck 1, but are constant if the dump truck 1 is the same type, specification, and model. It is determined as a (predetermined) characteristic.

  Here, consider a case in which the possibility of contact with an obstacle (determination as to whether or not to start braking) is determined based on the actual braking characteristics shown in FIG. In this case, as shown in FIG. 6, the cooperative brake has higher braking characteristics (shorter braking distance) than the electric brake. For this reason, when the obstacle is detected ahead by the millimeter wave radar 32 while the dump truck 1 is traveling at a constant speed, the electric brake alarm is issued from the monitor device 38 before the cooperative brake alarm. It is done. Then, after the electric brake alarm is issued, when the dump truck 1 further approaches an obstacle, a cooperative brake alarm is issued from the monitor device 38.

  However, in FIG. 6, the difference (braking distance difference) between the braking characteristic (braking distance) of the electric brake and the braking characteristic (braking distance) of the cooperative brake is large in the high speed range and small in the low speed range. For this reason, in the low speed range, there is a possibility that the time from when the electric brake warning is issued until the cooperative brake warning is issued may be shortened. That is, the timing at which the electric brake alarm is issued from the monitor device 38 (that is, the timing at which the first braking start signal is output from the contact possibility determination unit 37) is set as the first timing, and the cooperative brake alarm is issued from the monitor device 38. When the timing to be issued (that is, the timing at which the second braking start signal is output from the contact possibility determination unit 37) is the second timing, the first timing may be close to the second timing. There is.

  Thereby, in a low speed range, for example, an electric brake alarm is issued, and a cooperative brake alarm may be issued immediately after the operator attempts to depress the brake pedal of the electric brake based on the alarm. At this time, for example, if the interval between the electric brake alarm (first timing) and the cooperative brake alarm (second timing) is about 1 second (for example, 3 seconds or less), the operator's operation of the brake pedal is There is a possibility that the brake pedal depressing operation is delayed without catching up with the alarm.

  Therefore, in the first embodiment, the contact possibility determination controller 34 sets the signal output timing (first timing) for outputting the first braking start signal when the traveling speed of the dump truck 1 is in the low speed range. It is configured to be fast. That is, in the low speed range, the contact possibility determination controller 34 sets the signal output timing for outputting the first braking start signal to the original signal output timing (the signal based on the determination based on the actual braking characteristics shown in FIG. 6). Output timing).

  The contact possibility determination controller 34 determines whether or not braking by the electric brake should be started when the traveling speed of the dump truck 1 is in the low speed range in order to advance the signal output timing for outputting the first braking start signal. In this configuration, there is a margin in the braking characteristics of the electric brake used for the determination. That is, in the first embodiment, the contact possibility determination controller 34 is configured to output the signal output timing based on the braking characteristics shown in FIG.

  In FIG. 5, in order to provide a margin for the braking characteristics of the electric brake, the braking distance of the electric brake is compared with the actual (original) braking distance (the braking characteristics of the electric brake in FIG. 6, ie, FIG. 5) in the low speed range. Therefore, it is longer than the characteristic indicated by a broken line. In other words, in the first embodiment, the braking characteristic of the electric brake used in the contact possibility determination controller 34 is set to an offset with respect to the actual braking characteristic (actual braking characteristic in a predetermined environment shown in FIG. 6). It is added. That is, the braking characteristics of the electric brake are corrected so that the performance is lower than the actual braking characteristics.

  Here, in the low speed range, for example, the difference between the first timing and the second timing (braking distance difference) is equal to or less than a preset threshold, that is, the braking characteristics (braking performance) of the electric brake and the braking characteristics of the cooperative brake. It can be set as a speed range in which the difference (characteristic difference, performance difference) from (braking performance) is not more than a preset threshold value. For example, in the low speed range, the speed at which the interval between the electric brake alarm (first timing) and the cooperative brake alarm (second timing) is 3 seconds or less (more preferably 2 seconds or less, more preferably 1 second or less). Can be set as the low speed range.

  The extent to which the first timing is advanced, that is, the extent to which an offset (correction) is added to the actual braking characteristics (braking performance) (the extent to be longer than the actual braking distance in FIG. 6) is the brake of the operator. It is obtained in advance by experiment, simulation, calculation, or the like (preliminary setting) so that the operation of the pedal can be delayed. Thereby, in 1st Embodiment, it can avoid that the space | interval of a 1st timing and a 2nd timing becomes short in a low speed area. Furthermore, as the first timing is advanced, the operator can depress the brake pedal for electric brake with a margin, and the inertia force (deceleration) due to deceleration applied to the operator can be reduced.

  The vehicle braking device 31 according to the first embodiment has the above-described configuration, and the operation thereof will be described next.

  When an operator who has entered the cab 11 of the dump truck 1 starts the engine 12, power is generated by the generator 13, and a hydraulic pump serving as a hydraulic source is rotationally driven. When the dump truck 1 is traveling, electric power is supplied from the generator 13 to the electric motor 14 via the motor control device 15 according to the operation of the accelerator pedal by the operator, whereby the electric motor 14 rotates and the rear wheels 3 is rotationally driven.

  When the operator operates (depresses) an electric brake brake pedal, an electric brake as a first brake, that is, a braking force generated by power generation (regenerative torque) of the electric motor 14 is applied. When the operator operates (depresses) the brake pedal for cooperative brake, the cooperative brake as the second brake, that is, the braking force by the electric motor 14 and the braking force by the disc brake 24 are applied.

  When the dump truck 1 is traveling, the millimeter wave radar 32 always displays obstacle information including information on the distance between the obstacle existing around the dump truck 1 and the dump truck 1 (predetermined control). Detect). The millimeter wave radar 32 always outputs the detected obstacle information to the contact possibility determination controller 34 of the obstacle detection device 33 (with a predetermined control cycle). In addition, when the dump truck 1 is traveling, the vehicle body controller 16 uses the vehicle information including information on the traveling speed of the dump truck 1 (corresponding to wheel speed) to the contact possibility determination controller of the obstacle detection device 33. 34 is always output (with a predetermined control cycle).

  Whether or not the contact possibility determination controller 34 should start braking by the electric brake from the braking characteristics of the electric brake (braking characteristics of the electric brake in FIG. 5), the obstacle information, and the vehicle information while the dump truck 1 is traveling. Is always determined (with a predetermined control cycle). Further, the contact possibility determination controller 34 should start braking by the cooperative brake from the braking characteristic of the cooperative brake (the braking characteristic of the cooperative brake in FIG. 5), the obstacle information, and the vehicle information while the dump truck 1 is traveling. Is always determined (with a predetermined control cycle). In this case, the braking characteristics of the electric brake (braking characteristics of the electric brake in FIG. 5) and the braking characteristics of the cooperative brake (braking characteristics of the cooperative brake in FIG. 5) Adjustment (correction) according to the load capacity) and gradient.

  When the contact possibility determination controller 34 determines that braking by the electric brake should be started, the controller 34 outputs a first braking start signal to the monitor device 38. Further, when the contact possibility determination controller 34 determines that the braking by the cooperative brake should be started, it outputs a second braking start signal to the monitor device 38. The monitor device 38 issues an electric brake warning based on the first braking start signal, and issues a cooperative brake warning based on the second braking start signal. The operator touches the obstacle by operating (depressing) the brake pedal for electric brake with the electric brake alarm and / or operating (depressing) the brake pedal for electric brake with the cooperative brake alarm. Can be avoided.

  In this case, in the first embodiment, when the traveling speed of the dump truck 1 is in the low speed range, the contact possibility determination controller 34 increases the timing at which the first braking start signal is output. For this reason, when the traveling speed of the dump truck 1 is in a low speed region, it is possible to secure a time from when the first braking start signal is output until when the second braking start signal is output. Thereby, it can suppress that an electric brake warning and a cooperation brake warning are output for a short time. As a result, the brake operation of the operator can be prevented from being delayed as compared with the configuration in which the electric brake alarm and the cooperative brake alarm are output in a short time. In addition, since the timing for outputting the electric brake alarm is advanced, the deceleration due to the electric brake can be reduced.

  Further, in the first embodiment, the contact possibility determination controller 34 makes the electric brake when the traveling speed of the dump truck 1 is in the low speed range in order to advance the signal output timing for outputting the first braking start signal. The braking characteristic of the electric brake used for determining whether or not to start braking by the above is provided with a margin. That is, as shown in FIG. 5, the braking distance of the electric brake is made longer in the low speed range than the actual (original) braking distance shown in FIG. Increase safety factor). As a result, the timing for outputting the first braking start signal can be advanced with a simple configuration without requiring complicated calculations.

  Next, FIG. 7 shows a second embodiment. The feature of the second embodiment is that the second braking start signal is not output when the traveling speed of the vehicle is in a low speed range. Note that in the second embodiment, the same components as those in the first embodiment described above are denoted by the same reference numerals, and description thereof is omitted.

  FIG. 7 shows the braking characteristic of the electric brake (first brake) and the braking characteristic of the cooperative brake (second brake) used in the second embodiment. As shown by a solid line in FIG. 7, the braking characteristics of the cooperative brake are set at a traveling speed (high speed range) where the traveling speed of the dump truck 1 is higher than the low speed range, but not set at a low speed range (for example, In the low speed range, the braking distance is 0 m). The broken lines in FIG. 7 are shown for comparison with the braking characteristics of the actual electric brake and the cooperative brake (FIG. 6), and are not set in the second embodiment.

  In the second embodiment, the contact possibility determination controller 34 determines whether or not braking by the cooperative brake should be started, based on the braking characteristic of the cooperative brake shown in FIG. 7 (the braking set only in the high speed region higher than the low speed region). Characteristics). As a result, when the traveling speed of the dump truck 1 is in the high speed range, the contact possibility determination controller 34 outputs a second braking start signal (issues a cooperative brake warning), and the traveling speed of the dump truck 1 is low. When in the range, the second braking start signal is not output (the cooperative brake warning is not issued). In other words, the contact possibility determination controller 34 outputs the first braking start signal (issues an electric brake alarm) in the low speed range, but does not output the second braking start signal (cooperative brake alarm). Does not emit).

  The second embodiment does not output the second braking start signal when the traveling speed of the dump truck 1 is in the low speed region as described above. The basic operation of the second embodiment is the same as that of the first embodiment described above. There is no particular difference from the form.

  In particular, in the second embodiment, when the contact possibility determination controller 34 does not output the second braking start signal in the low speed range (does not output the cooperative brake warning), the timing at which the electric brake warning is output in the low speed range. And the timing at which the cooperative brake warning is output can be reliably avoided. Moreover, since the timing at which the electric brake alarm is output is early, the dump truck 1 can be stopped with a sufficient margin by braking the electric brake even if the cooperative brake alarm is not output.

  Next, FIG. 8 shows a third embodiment. A feature of the third embodiment is that the first braking start signal is not output when the traveling speed of the vehicle is in a low speed range. Note that in the third embodiment, the same components as those in the first embodiment described above are denoted by the same reference numerals, and description thereof is omitted.

  FIG. 8 shows the braking characteristics of the electric brake (first brake) and the braking characteristics of the cooperative brake (second brake) used in the third embodiment. As shown by a solid line in FIG. 8, the braking characteristics of the electric brake are set at a traveling speed (high speed region) where the traveling speed of the dump truck 1 is higher than the low speed region, but not set at a low speed region (for example, In the low speed range, the braking distance is 0 m). The broken line in FIG. 8 is shown for comparison with the actual braking characteristics of the electric brake (FIG. 6), and is not set in the third embodiment.

  In the third embodiment, the contact possibility determination controller 34 determines whether or not braking by the electric brake should be started, based on the braking characteristics of the electric brake shown in FIG. 8 (the braking set only in the high speed range higher than the low speed range). Characteristics). As a result, when the traveling speed of the dump truck 1 is in the high speed range, the contact possibility determination controller 34 outputs the first braking start signal (issues an electric brake alarm), and the traveling speed of the dump truck 1 is low. When in the range, the first braking start signal is not output (the electric brake alarm is not issued).

  On the other hand, the contact possibility determination controller 34 is configured to output a second braking start signal in the entire traveling region of the traveling speed of the dump truck 1. In summary, the contact possibility determination controller 34 outputs a second braking start signal (issues a cooperative brake alarm) when in a low speed range, but does not output a first braking start signal (outputs an electric brake alarm). Does not emit).

  The third embodiment does not output the first braking start signal when the traveling speed of the dump truck 1 is in the low speed region as described above. The basic operation of the third embodiment is the same as that of the first embodiment described above. There is no particular difference from the form.

  That is, in the third embodiment, when the contact possibility determination controller 34 does not output the second braking start signal in the low speed range (does not output the cooperative brake warning), the timing at which the electric brake warning is output in the low speed range. And the timing at which the cooperative brake warning is output can be reliably avoided. That is, since there is no electric brake warning, it is possible to suppress the delay of the pedal operation by the operator based on the cooperative brake warning.

  Next, FIG. 9 shows a fourth embodiment. A feature of the fourth embodiment is that the first braking start signal is not output when the vehicle traveling speed is in a low speed range, and the signal output timing for outputting the second braking start signal is advanced. It is in the configuration to do. Note that in the fourth embodiment, the same components as those in the first embodiment described above are denoted by the same reference numerals, and description thereof is omitted.

  FIG. 9 shows the braking characteristics of the electric brake (first brake) and the braking characteristics of the cooperative brake (second brake) used in the fourth embodiment. As shown in FIG. 9, the braking characteristics of the electric brake are set such that the traveling speed of the dump truck 1 is higher than the low speed range (high speed range), as in the third embodiment (represented by a solid line). Is not set in the low speed range (for example, the braking distance is 0 m in the low speed range). The broken lines in FIG. 9 are shown for comparison with the braking characteristics of the actual electric brake and the cooperative brake (FIG. 6), and are not set in the fourth embodiment.

  Furthermore, in the fourth embodiment, a margin is provided for the braking characteristics of the cooperative brake in the low speed range. That is, in the fourth embodiment, the braking distance of the electric brake is represented by the actual braking distance (the braking characteristic of the cooperative brake in FIG. 6, that is, the broken line in FIG. 9 for comparison in the low speed range. Longer than the characteristic). In other words, the braking characteristic of the cooperative brake is obtained by adding an offset to the actual braking characteristic (corrected so that the performance is lower than the actual braking characteristic).

  In the fourth embodiment, the contact possibility determination controller 34 determines whether or not the braking by the electric brake should be started, based on the braking characteristics of the electric brake shown in FIG. 9 (the braking set only in the high speed range higher than the low speed range). Characteristics) and whether to start braking by cooperative braking is determined using the braking characteristics (braking characteristics offset in the low speed range) of the cooperative brake shown in FIG. As a result, the contact possibility determination controller 34 outputs the first braking start signal (issues an electric brake alarm) when the traveling speed of the dump truck 1 is in the high speed range, as in the third embodiment. However, when the traveling speed of the dump truck 1 is in the low speed range, the first braking start signal is not output (the electric brake alarm is not issued).

  Furthermore, in the fourth embodiment, the contact possibility determination controller 34 uses the braking characteristics of the cooperative brake shown in FIG. 9 to output a second braking start signal when in the low speed range. It is the composition which speeds up. That is, in the low speed range, the contact possibility determination controller 34 sets the signal output timing for outputting the second braking start signal to the original signal output timing (the signal based on the determination based on the actual braking characteristics shown in FIG. 6). Output timing).

  In the fourth embodiment, as described above, when the traveling speed of the dump truck 1 is in the low speed range, the first brake start signal is not output, and the signal output timing at which the second brake start signal is output is set. The basic operation is not particularly different from those according to the first embodiment and the third embodiment described above.

  In particular, in the fourth embodiment, the contact possibility determination controller 34 makes the signal output timing for outputting the second braking start signal in the low speed range earlier, thereby stopping the dump truck 1 with a margin by the braking of the cooperative brake. be able to.

  Next, FIG. 10 shows a fifth embodiment. The feature of the fifth embodiment is that the electric brake is automatically applied by the output of the first braking start signal, and the cooperative brake is automatically applied by the output of the second braking start signal. is there. Note that in the fifth embodiment, the same components as those in the first embodiment described above are denoted by the same reference numerals, and description thereof is omitted.

  In the fifth embodiment, the obstacle detection device 41 includes only the contact possibility determination controller 34 (the monitor device 38 is omitted). In the fifth embodiment, the contact possibility determination unit 37 of the contact possibility determination controller 34 is connected to the vehicle body controller 16. More specifically, the contact possibility determination unit 37 is connected to the vehicle body control unit 42 of the vehicle body controller 16. The vehicle body control unit 42 receives the first braking start signal and the second braking start signal from the contact possibility determination unit 37.

  The vehicle body control unit 42 performs control to automatically apply the electric brake when the first braking start signal is input. That is, when the first braking start signal is input, the vehicle body control unit 42 outputs a torque signal corresponding to the braking force to be applied by the electric motor 14 to the electric motor 14. Thereby, the electric brake by the electric motor 14 can be provided automatically.

  The vehicle body control unit 42 performs control to automatically apply the cooperative brake when the second braking start signal is input. That is, when the second braking start signal is input, the vehicle body control unit 42 outputs a torque signal to the electric motor 14 and also outputs a brake operation signal serving as a command for supplying brake fluid pressure to the disc brake 24. . The brake operation signal is output, for example, to a brake hydraulic pressure supply device (not shown) connected to the cylinder of the caliper 24B of the disc brake 24 via a hydraulic line. Thereby, the cooperative brake by the electric motor 14 and the disc brake 24 can be automatically applied.

  For example, the braking characteristics shown in FIG. 5 can be used as the braking characteristics of the electric brake and the cooperative brake used in the contact possibility determination controller 34. However, the present invention is not limited to this. For example, the braking characteristics shown in FIG. 7, the braking characteristics shown in FIG. 8, or the braking characteristics shown in FIG. 9 may be used.

  In the fifth embodiment, as described above, the electric brake is automatically applied by the output of the first braking start signal, and the cooperative brake is automatically applied by the output of the second braking start signal. Regarding the basic action, there is no particular difference from that according to the first embodiment described above.

  In particular, in the fifth embodiment, the time from when the first braking start signal is output to when the second braking start signal is output can be secured, as in the first embodiment. Thereby, it can suppress that braking of a cooperation brake is used frequently. That is, replacement of the disk rotor 24A and / or the friction pad 24C of the disk brake 24 can be suppressed. As a result, the cost for replacement can be reduced, and the conveyance efficiency (operation efficiency) can be improved by reducing the replacement time.

  In the fifth embodiment, the case where the first braking start signal and the second braking start signal are configured to be output only to the vehicle body controller 16 (vehicle body control unit 42) has been described as an example. However, the present invention is not limited to this. For example, the first braking start signal and the second braking start signal may be output to both the monitor device and the vehicle body controller (vehicle body control unit). In this case, the timing at which the first braking start signal is output to the monitor device and the timing at which the first brake start signal is output to the vehicle body controller (vehicle body control unit) can be made different (for example, the timing to output to the monitor device is advanced). In addition, the timing at which the second braking start signal is output to the monitoring device and the timing at which the second braking start signal is output to the vehicle body controller (vehicle body control unit) can be made different (for example, the timing at which the second braking start signal is output to the monitoring device is advanced).

  In each of the embodiments, the case where the first braking start signal and the second braking start signal are output once has been described as an example. That is, the case where the electric brake alarm and the cooperative brake alarm are each output once has been described as an example. However, the present invention is not limited to this. For example, the first braking start signal and / or the second braking start signal may be output a plurality of times. For example, the first braking start signal output timing (electric brake alarm) may be performed twice (the degree of possibility of contact is divided into two stages and output at each stage).

  In each embodiment, the case where it was set as the structure which uses the dry-type disc brake 24 as a friction type mechanical brake was demonstrated as an example. However, the present invention is not limited to this. For example, the mechanical brake may be constituted by other types (types) of brakes such as a drum brake and a wet multi-disc brake, and the mechanical brake may be a dry disc, for example. You may comprise by both a brake and a wet multi-disc disc brake. That is, various brakes that can apply a braking force to the vehicle (wheel) can be used as the mechanical brake.

  In each embodiment, the first brake is an electric brake that applies braking force by the electric motor 14, and the second brake is cooperation that applies both braking force by the electric motor 14 and braking force by the disc brake 24. The case of using a brake (electric brake + mechanical brake) has been described as an example. However, the present invention is not limited to this. For example, the first brake may be an electric brake and the second brake may be a mechanical brake. The first brake may be a first mechanical brake, and the second brake may be a second mechanical brake having higher braking characteristics than the first mechanical brake. Further, the first brake may be a first electric brake, and the second brake may be a second electric brake having higher braking characteristics than the first electric brake. That is, the first brake can be selected from one or more of various brakes that can apply a braking force to the vehicle (wheel), and the second brake has a higher braking characteristic than the first brake ( One or a plurality of brakes can be selected from various brakes that can apply a braking force to the vehicle (wheel) so that the braking distance is short.

  In each embodiment, the detection signals of the accelerator operation sensor 17, the electric brake operation amount sensor 18, the cooperative brake operation switch 19, the wheel speed sensor 20, the steering sensor 21, the load sensor 22, and the gradient sensor 23 are sent to the vehicle body controller 16. In the above description, an example in which the obstacle is input to the obstacle detection device 33 (the contact possibility determination controller 34) is described as an example. However, the present invention is not limited to this, and detection signals relating to vehicle information necessary for determining the possibility of contact with an obstacle (determining whether or not to start braking) can be detected by, for example, each sensor and switch without using a vehicle body controller. It is good also as a structure which inputs into a direct contact possibility determination controller (a 1st braking command output part and a 2nd braking command output part) from the above.

  In the first embodiment and the second embodiment, in order to speed up the signal output timing for outputting the first braking start signal in the low speed range, the braking characteristics of the electric brake (first brake) are The case where the configuration has a margin with respect to the actual (original) braking characteristics has been described as an example. More specifically, the case where the braking distance of the electric brake in the low speed range is corrected to be longer than the actual braking distance has been described as an example.

  However, the present invention is not limited to this. For example, the first brake used for determining the possibility of contact with an obstacle (determining whether or not to start braking) is used, for example, in order to allow a sufficient braking characteristic of the first brake. A configuration may be adopted in which the braking force of the brake is corrected to be smaller than the braking force actually applied in the low speed range. Moreover, it is good also as a structure which correct | amends the vehicle speed used for determination of the possibility of a contact with an obstruction that a speed becomes large with respect to an actual vehicle degree. Furthermore, it is good also as a structure which correct | amends so that the distance between the obstacle used for determination of the possibility of a contact with an obstacle and a vehicle may become short with respect to an actual distance. In other words, in the low speed range, various values (state quantity, characteristic value, performance value) used for determining the possibility of contact with an obstacle are corrected to give a margin to the actual value (performance of the first brake). By performing the correction that lowers the signal, the signal output timing for outputting the first braking start signal can be advanced in the low speed region.

  In the fourth embodiment, since the signal output timing for outputting the second braking start signal is advanced in the low speed range, the braking characteristic of the cooperative brake (second brake) is set to the actual (original) braking in the low speed range. The case where the configuration has a margin for the characteristics has been described as an example. More specifically, the case has been described as an example in which the braking distance of the cooperative brake in the low speed range is corrected to be longer than the actual braking distance.

  However, the present invention is not limited to this. For example, in order to give a margin to the braking characteristics of the second brake, for example, the second brake used for determining the possibility of contact with an obstacle (determining whether braking should be started). A configuration may be adopted in which the braking force of the brake is corrected to be smaller than the braking force actually applied in the low speed range. Moreover, it is good also as a structure which correct | amends the vehicle speed used for determination of the possibility of a contact with an obstruction that a speed becomes large with respect to an actual vehicle degree. Furthermore, it is good also as a structure which correct | amends so that the distance between the obstacle used for determination of the possibility of a contact with an obstacle and a vehicle may become short with respect to an actual distance. In other words, in the low speed range, various values (state quantities, characteristic values, performance values) used for determining the possibility of contact with an obstacle are corrected to give a margin to the actual values (second brake performance). By performing the correction to reduce the signal, the signal output timing for outputting the second braking start signal can be advanced in the low speed region.

  In the second embodiment, the third embodiment, and the fourth embodiment, the braking characteristics of the electric brake or the cooperative brake are set so as not to output the braking start signal of the electric brake or the cooperative brake in the low speed range. In the above description, the case where is not set in the low speed range (the braking distance is set to 0 m in the low speed range) has been described as an example. However, the present invention is not limited to this. For example, by setting the braking characteristics of the electric brake or the cooperative brake in the entire speed range and determining whether the vehicle speed is in the low speed range, a braking start signal in the low speed range is determined. May not be output.

  In each embodiment, as vehicle information used for determination of the possibility of contact with an obstacle (determination of whether or not to start braking), information on operation of an electric brake, information on the presence or absence of operation of a cooperative brake, As an example, a case has been described where wheel speed information corresponding to travel speed, vehicle steering direction information, vehicle load information, and gradient information where the vehicle is located are used. However, the present invention is not limited to this, and the vehicle information may be, for example, only information on the traveling speed of the vehicle. Alternatively, for the vehicle information, in addition to the above information, for example, various types of information related to the vehicle state and the vehicle environment such as information on the road surface on which the vehicle travels can be used. That is, as the vehicle information, various types of information regarding the vehicle state and the traveling environment including information on the traveling speed of the vehicle can be used.

  In each embodiment, as the obstacle information used for the determination of the possibility of contact with the obstacle (determination of whether or not to start braking), information on the distance between the obstacle and the vehicle, The case where the configuration using the information on the relative speed is taken as an example. However, the present invention is not limited to this, and the obstacle information may be only the distance between the obstacle and the vehicle, for example. Alternatively, as the obstacle information, various types of information related to the obstacle such as information on the type of the obstacle and information on the temperature of the obstacle can be used in addition to the above information. That is, as the obstacle information, various types of information regarding the obstacle including information on the distance between the obstacle and the vehicle can be used.

  In each embodiment, the case where the configuration using the millimeter wave radar 32 is used as the sensor for detecting an obstacle (external field recognition sensor) has been described as an example. However, the present invention is not limited to this, in addition to millimeter wave radar, for example, radars such as laser radars and infrared radars (for example, light emitting elements such as semiconductor lasers and light receiving elements for receiving them), and / or stereo cameras and single cameras A camera such as a digital camera can be used.

  In each embodiment, the case where the vehicle braking device 31 is mounted on a dump truck has been described as an example. However, the present invention is not limited to this. For example, the invention can be widely applied to vehicles including a first brake (for example, an auxiliary brake) and a second brake (for example, a main brake) having different braking performances such as a truck and a bus. Is.

  According to the above embodiment, it is possible to appropriately output a braking start command (braking start signal).

  That is, according to the embodiment, the first braking command output unit advances the timing of outputting the first braking start signal when the traveling speed of the vehicle is in the low speed range. For this reason, it is possible to secure the time from when the first braking start signal is output until the second braking start signal is output. Thus, for example, in the case of a configuration that issues an alarm to the operator (outputs an alert) by outputting a braking start signal, the alarm based on the first braking start signal and the alarm based on the second braking start signal are short. As compared with the configuration output at, it is possible to suppress the delay of the brake operation by the operator. On the other hand, in the case of a configuration in which automatic brake control is performed by outputting a brake start signal, the second brake is compared with a configuration in which the first brake start signal and the second brake start signal are output in a short time. It is possible to suppress the frequent use of braking. Furthermore, since the timing for outputting the first braking start signal is advanced, the deceleration due to braking of the first brake can be reduced.

  According to the embodiment, the first braking command output unit accelerates the signal output timing for outputting the first braking start signal. Therefore, when the vehicle traveling speed is in the low speed range, braking by the first brake is performed. The braking characteristic of the first brake used for determining whether or not to start the operation is given a margin. In this case, by setting the braking characteristic of the first brake lower than the actual braking characteristic (for example, making the braking distance longer than the actual braking distance or making the braking force smaller than the actual braking force), It is possible to give a margin to the braking characteristics of the brake 1 (increase the safety factor). As a result, the timing for outputting the first braking start signal can be advanced with a simple configuration without requiring complicated calculations.

  According to the embodiment, the second braking command output unit does not output the second braking start signal when the traveling speed of the vehicle is in the low speed range. Thereby, it can be avoided reliably that the timing of the output of the first braking start signal and the timing of the output of the second braking start signal are close. In addition, since the timing at which the first braking start signal is output is advanced, the vehicle can be stopped with a margin by the braking of the first brake without outputting the second braking start signal.

  According to the embodiment, the first braking command output unit does not output the first braking start signal when the traveling speed of the vehicle is in the low speed range. For this reason, it can be reliably avoided that the timing of the output of the first braking start signal is close to the timing of the output of the second braking start signal. Thus, for example, in the case of a configuration that issues an alarm to the operator (outputs an alert) by outputting a braking start signal, there is no alarm based on the first braking start signal. It is possible to suppress the brake operation of the based operator from being delayed.

  According to the embodiment, the second braking command output unit advances the signal output timing for outputting the second braking start signal when the traveling speed of the vehicle is in the low speed range. As a result, even when the first braking start signal is not output when the vehicle is in the low speed range, the vehicle can be stopped with a margin by the braking of the second brake.

1 Dump truck (vehicle)
14 Electric motor (first brake, second brake)
16 Body controller (vehicle information detection device)
17 Accelerator operation sensor (vehicle information detection device)
18 Electric brake operation amount sensor (vehicle information detection device)
19 Cooperative brake operation switch (vehicle information detection device)
20 Wheel speed sensor (vehicle information detection device)
21 Steering sensor (vehicle information detection device)
22 Load sensor (vehicle information detection device)
23 Gradient sensor (vehicle information detection device)
24 Disc brake (second brake)
31 Vehicle braking device 32 Millimeter wave radar (obstacle information detection device)
34 Contact possibility determination controller (first braking command output unit, second braking command output unit)

Claims (5)

A first brake for applying a first braking force to the vehicle;
A second brake having a braking characteristic higher than that of the first brake and applying a second braking force to the vehicle;
An obstacle information detecting device for detecting obstacle information including information on a distance between an obstacle present around the vehicle and the vehicle;
A vehicle information detection device for detecting vehicle information including information on the traveling speed of the vehicle;
When the vehicle is running, based on the braking characteristics of the first brake, the obstacle information, and the vehicle information, determine whether to start braking by the first brake; and A first braking command output unit that outputs a first braking start signal when it is determined that braking by the first brake should be started;
When the vehicle is running, based on the braking characteristics of the second brake, the obstacle information, and the vehicle information, determine whether to start braking by the second brake; and A braking device for a vehicle comprising: a second braking command output unit that outputs a second braking start signal when it is determined that braking by the second brake should be started;
The first braking command output unit is configured to advance a signal output timing for outputting the first braking start signal when the traveling speed of the vehicle is in a low speed range. apparatus.   The first braking command output unit starts braking by the first brake when the vehicle traveling speed is in a low speed range in order to accelerate the signal output timing for outputting the first braking start signal. The vehicular braking apparatus according to claim 1, wherein a margin is provided for a braking characteristic of the first brake used for determining whether or not to perform.   The second braking command output unit outputs the second braking start signal when the traveling speed of the vehicle is higher than a low speed range, and outputs the second braking start signal when the traveling speed of the vehicle is in a low speed range. The vehicular braking apparatus according to claim 1 or 2, wherein the braking start signal is not output. A first brake for applying a first braking force to the vehicle;
A second brake having a braking characteristic higher than that of the first brake and applying a second braking force to the vehicle;
An obstacle information detecting device for detecting obstacle information including information on a distance between an obstacle present around the vehicle and the vehicle;
A vehicle information detection device for detecting vehicle information including information on the traveling speed of the vehicle;
When the vehicle is running, based on the braking characteristics of the first brake, the obstacle information, and the vehicle information, determine whether to start braking by the first brake; and A first braking command output unit that outputs a first braking start signal when it is determined that braking by the first brake should be started;
When the vehicle is running, based on the braking characteristics of the second brake, the obstacle information, and the vehicle information, determine whether to start braking by the second brake; and A braking device for a vehicle comprising: a second braking command output unit that outputs a second braking start signal when it is determined that braking by the second brake should be started;
The first braking command output unit outputs the first braking start signal when the traveling speed of the vehicle is higher than a low speed range, and outputs the first braking signal when the traveling speed of the vehicle is in a low speed range. 1 is configured not to output a braking start signal,
The vehicular braking apparatus, wherein the second braking command output unit outputs the second braking start signal in the entire traveling range of the traveling speed of the vehicle.   The vehicle-use vehicle according to claim 4, wherein the second braking command output unit is configured to advance a signal output timing for outputting the second braking start signal when the traveling speed of the vehicle is in a low speed range. Braking device.

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