JP2005343313A - Control device of industrial vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a control device of an industrial vehicle capable of ensuring the safety by adequately regulating the rocking of a suspension. <P>SOLUTION: The control device of the industrial vehicle comprises a first determination means to determine whether or not the traveling speed is not less than the preset reference traveling speed, a second determination means to determine whether or not the traveling acceleration is not less than the preset reference traveling acceleration, a third determination means to determine whether or not the steering angle is not less than the preset reference steering angle, a fourth determination means to determine whether or not the steering angular velocity is not less than the preset reference steering angular velocity, and a control means which determines whether or not a rocking regulating device is in an operational state or a non-operational state according to the result of determination of the first to fourth determination means, and controls the rocking regulating device to be changed to either state. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a control device that controls a swing restricting device in an industrial vehicle including a suspension device that suspends wheels and a swing restricting device that restricts swinging of the suspension device.

  Conventionally, in industrial vehicles, when a suspension device for suspending wheels is supported on a vehicle body so as to be swingable, for example, the suspension device swings during turning and the stability of the vehicle body is impaired. In view of this, for example, as shown in Patent Document 1, there has been proposed a technique for restricting the swing of the suspension device by the swing restricting device when each of the traveling speed and the steering angle is equal to or greater than a reference value. In addition, as shown in Patent Document 2, a technique has been proposed in which swing is restricted by a swing restriction device when each of the traveling speed and the rotational speed of the steering is equal to or higher than a reference value.

  In addition to the above, as shown in Patent Document 3, for example, an allowable value of the steering angle is obtained from the acceleration in the traveling direction, and when the actual steering angle is equal to or larger than the allowable value, the swing regulating device swings the suspension device. Technology has been proposed that regulates movement, obtains the allowable value of the running speed from the change rate of the rudder angle, and regulates the swing by the swing regulating device when the actual running speed is above this allowable value. Yes.

JP 58-214406 A JP 2001-163596 A JP 2000-177352 A

  There are several possible conditions for restricting the swinging of the suspension system. For example, if this condition is relatively easily satisfied in order to make the swinging easy to be controlled, it is not very safe. Although there is no problem, the swing is restricted, and as a result, the rider feels uncomfortable riding. For this reason, it is important not to restrict the swinging in order to avoid danger, but to regulate it under appropriate conditions. In addition, it is advantageous in terms of safety to determine whether or not the conditions for regulation are satisfied, so that it can be easily performed without complicated processing and without requiring a complicated configuration. It is convenient for implementation.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to ensure safety by appropriately regulating swinging of a suspension device.

  In order to achieve the above object, the present invention includes a suspension device provided with a drive wheel and a steering wheel on a vehicle body, and swingably provided on the vehicle body to suspend the drive wheel or the steering wheel, and the suspension device. In an industrial vehicle including a swing restricting device that restricts swinging of the suspension device, the swing restricting device is selectively controlled between an operating state in which swinging of the suspension device is restricted and a non-operating state in which the restriction is released And a speed deriving unit for deriving a traveling speed of the vehicle, an acceleration deriving unit for deriving a traveling acceleration of the vehicle, an angle deriving unit for deriving a steering angle of the steering wheel, and the steering wheel. An angular velocity deriving unit for deriving the steering angular velocity, a first determination unit for determining whether or not the traveling speed is equal to or higher than a preset reference traveling speed, and a reference for which the traveling acceleration is set in advance. More than running acceleration A second determination means for determining whether or not the steering angle, a third determination means for determining whether or not the steering angle is equal to or greater than a preset reference steering angle, and the steering angular velocity is preset. And a fourth determination means for determining whether or not the steering angular velocity is equal to or higher than a reference steering angular velocity, and further, depending on a determination result of the first to fourth determination means, the swing restriction device is operated in the operating state. Or a non-operating state, and a switching control means for performing control to switch the swing restricting device to either of the two states.

  According to the present invention as described above, it is determined whether the swing restricting device is to be activated or deactivated from the four parameters of traveling speed, traveling acceleration, steering angle, and steering angular speed. Judgment can be made under conditions. As a result, for example, during a sudden turning or acceleration / deceleration, the swing regulating device can be operated to regulate the swinging of the suspension device to ensure the safety of the vehicle. When traveling at a constant speed, the rocking restriction device is deactivated to release the rocking restriction, and the suspension device rocks according to the road surface condition or the like, so that a good riding comfort can be obtained. In addition, since both safety and riding comfort are ensured in this way, the driver can drive with peace of mind. In addition, what is necessary is just to set suitably each value of said reference | standard driving speed, a reference | standard driving acceleration, a reference | standard steering angle, and a reference | standard steering angular velocity according to the form of the industrial vehicle to which this invention is applied.

  In the present invention, the switching control means determines that the travel speed is greater than or equal to the reference travel speed by the first determination means, and the steering angle is greater than or equal to the reference steering angle by the third determination means. When it is determined that there is, the swing restricting device is determined to be in the operating state, and the first determination means determines that the travel speed is not equal to or higher than the reference travel speed, or the third determination. When it is determined by the means that the steering angle is not greater than or equal to the reference steering angle, the swing restricting device can be determined to be in the inoperative state.

  According to this, when the traveling speed is equal to or higher than the reference traveling speed and the steering angle is equal to or larger than the reference steering angle, it is considered that the vehicle body may become unstable. In this case, the required swing control can be performed. On the other hand, when the traveling speed is not equal to or higher than the reference traveling speed or the steering angle is not equal to or higher than the reference steering angle, it is considered that there is no possibility that the vehicle body becomes unstable. As a result, it is possible to prevent unnecessary oscillation from being restricted.

  In the present invention, the switching control means may determine that the travel acceleration is greater than or equal to the reference travel acceleration by the second determination means, or the steering angular velocity is determined to be the reference steering by the fourth determination means. When it is determined that the angular velocity is greater than or equal to the angular velocity, it is determined that the swing restricting device is in the operating state, the third determination unit determines that the travel acceleration is not greater than the reference travel acceleration, and When the fourth determining means determines that the steering angular velocity is not equal to or higher than the reference steering angular velocity, the swing restricting device may be determined to be in the inoperative state.

  According to this, it is considered that the vehicle body may become unstable when the travel acceleration is equal to or higher than the reference travel acceleration or the steering angular velocity is equal to or higher than the reference steering angular velocity. Regulation can be made. On the other hand, when the traveling acceleration is not equal to or higher than the reference traveling acceleration and the steering angular velocity is not equal to or higher than the reference steering angular velocity, it is considered that the vehicle body is not likely to be unstable, and therefore it is determined that the swing restriction device is in an inoperative state. As a result, it is possible to prevent unnecessary oscillation from being restricted.

  Further, in the present invention, the switching control means determines that the swing regulating device is in the operating state based on the determination results of the first determination means and the third determination means, or the second control means Based on the determination results of the determination means and the fourth determination means, when it is determined that the swing restricting device is in the operating state, control is performed to switch the swing restricting device to the operating state, and Based on the determination results of the first determination means and the third determination means, it is determined that the swing regulating device is in the non-operating state, and the determination results of the second determination means and the fourth determination means are On the basis of this, when it is determined that the rocking restriction device is in the non-operating state, a control for switching the rocking restriction device to the non-operating state can be performed.

  According to this, when the vehicle body may become unstable as viewed from the traveling speed and the steering angle, or the vehicle body may become unstable as viewed from the traveling acceleration and the steering angular velocity, The device is switched to the operating state, and swinging of the suspension device is restricted. On the other hand, when there is no possibility that the vehicle body becomes unstable as viewed from the traveling speed and the steering angle, and there is no possibility that the vehicle body becomes unstable as viewed from the traveling acceleration and the steering angular speed, the swing regulating device is not activated. The state is switched, and the restriction on the swing of the suspension device is released. Therefore, it is possible to prevent the suspension device from being restricted from being swung, and to restrict the suspension device from being swung only when it is really necessary.

  In the above-described configuration, the acceleration deriving unit can derive the traveling acceleration by performing a time differential operation on the traveling speed derived by the speed deriving unit. According to this, as long as the traveling speed is derived by the traveling speed deriving means, the traveling acceleration can be obtained from the derivation result by calculation processing. That is, for example, the traveling acceleration can be obtained by effectively utilizing the traveling speed deriving means provided for other purposes such as traveling control of the drive wheels, and the configuration can be simplified.

  In the above configuration, the steering angular velocity deriving unit can calculate the steering angular velocity by performing a time differential operation on the steering angle derived by the steering angle deriving unit. According to this, as long as the steering angle of the steered wheel is derived by the steering angle deriving means, the steering angular velocity can be obtained from the derivation result by calculation processing. That is, for example, the steering angle derivation means provided for other purposes such as steering control of the steered wheel can be effectively used to obtain the steering angular velocity, and the configuration can be simplified.

  As described above, according to the present invention, it is determined whether the swing regulating device is to be activated or deactivated from the four parameters of traveling speed, traveling acceleration, steering angle, and steering angular speed. The determination can be performed under more detailed conditions. As a result, safety can be ensured by appropriately controlling / releasing the swing of the suspension device, and the driver can operate with peace of mind.

  Hereinafter, an embodiment in which the present invention is applied to a counterbalance forklift will be described with reference to the drawings.

  As shown in FIG. 1, this counterbalance forklift is provided with a lift device 2 at the front of a vehicle body 1, a battery 3 is mounted at the center in the front-rear direction of the vehicle body 1, and a counterweight 4 at the rear of the vehicle body 1. Is provided. A front wheel 5 as a driving wheel is provided at the lower front part of the vehicle body 1, and a rear wheel 6 as a steering wheel is provided at the lower rear part of the vehicle body 1. As shown in FIG. 2, the rear wheel 6 is provided on the vehicle body 1 via a rear wheel suspension device 7, and the rear wheel suspension device 7 is supported to be swingable up and down with respect to the vehicle body 1. Further, the vehicle body 1 is equipped with a control device 8 between the battery 3 and the counterweight 4, and a travel motor 9 for driving the front wheel 5 as a drive wheel at a position slightly rearward of the front wheel 5. The control device 8 controls the traveling motor 9 and an electromagnetic control valve 14 described later. The travel motor 9 has a built-in rotation sensor 10 that outputs a signal according to the number of rotations, and an output signal from the rotation sensor 10 is transmitted to the control device 8.

  As shown in FIG. 1, a seat 11 on which a driver sits is provided above the battery 3, and a head guard 12 is provided so as to cover the seat 11 from above. A steering wheel 16 for steering operation and a lever (not shown) for operating the lift device 2 are disposed at the front position of the seat 11, and an accelerator pedal 17 and a brake pedal (see FIG. Not shown). Then, when the driver depresses the accelerator pedal 17, the traveling motor 9 rotates according to this operation and the front wheel 5 is driven to travel, and the handle 16 is rotated and operated according to this operation. A rod of a cylinder 72 which will be described later is actuated, and the rear wheel 6 is turned to steer.

  As shown in FIGS. 1 and 2, a suspension cylinder 13 made of a hydraulic cylinder is provided so as to expand and contract vertically between the vehicle body 1 and the rear wheel suspension device 7, and the head side and the bottom side of the suspension cylinder 13 are provided. The electromagnetic control valve 14 is interposed on the hydraulic circuit connecting the two. The head side and the bottom side of the suspension cylinder 13 and the electromagnetic control valve 14 are connected to each other by a pipe 15, and the head side and the bottom side are communicated with each other by opening the electromagnetic control valve 14. The cylinder 13 can be expanded and contracted, and when the electromagnetic control valve 14 is closed, the hydraulic circuit is shut off and the suspension cylinder 13 cannot be expanded and contracted. The opening / closing operation of the electromagnetic control valve 14 is controlled by the control device 8 as described later, and the suspension cylinder 13, the electromagnetic control valve 14, and the pipe 15 correspond to the swing regulating device of the present invention. In the following description, the operation of closing the electromagnetic control valve 14 to make the suspension cylinder 13 inextensible is “locking”, and the operation of the electromagnetic control valve 14 is opened to make the suspension cylinder 13 extendable and retractable. Also called “unlocking”.

  As shown in FIG. 2, the rear wheel suspension device 7 is mainly supported by a frame 70 that is swingably supported by the vehicle body 1, left and right axles 71 that are pivotally supported by the frame 70, and a frame 70. The cylinder 72 is made up of. The frame 70 can swing up and down with respect to the vehicle body 1 about a horizontal axis directed in the front-rear direction of the vehicle body 1, and a suspension cylinder 13 is provided between the frame 70 and the vehicle body 1. Each of the axles 71 can turn about a vertical axis directed in the vertical direction. The rear wheel 6 is rotatably attached to the axles 71, and the axle 71 and the rear wheel 6 turn together. The cylinder 72 includes a rod that can move in the left-right direction. The rod has a left end connected to the left axle 71 and a right end connected to the right axle 71, and the axle 71 turns as the rod moves. . As shown in FIG. 2, a steering angle sensor 73 is provided on the turning shaft of the left axle 71, and a signal corresponding to the angle at which the left axle 71 turns is output. To be told.

  As shown in FIG. 3, the control device 8 includes a travel speed calculation means 80, a travel acceleration calculation means 81, a steering angle calculation means 82, a steering angular speed calculation means 83, a storage means 84, and a determination means 85. And a drive control means 86. The traveling speed calculation unit 80 calculates the traveling speed A using the output signal from the rotation sensor 10 and the relational data between the output signal of the rotation sensor 10 and the traveling speed A stored in the storage unit 84 in advance. The travel acceleration calculating means 81 calculates the travel acceleration B by differentiating the travel speed A calculated by the travel speed calculating means 80 with respect to time. The steering angle calculation means 82 uses the output signal from the steering angle sensor 73 and the relationship data between the output signal of the steering angle sensor 73 and the steering angle C stored in advance in the storage means 84, so that the steering angle C (straight forward). The steering angular velocity calculation means 83 calculates the steering angular velocity D by time-differentiating the steering angle C calculated by the steering angle calculation means 82 from the state. . The storage means 84 stores the data used for the calculation process as described above, and the reference travel speed A0, the reference travel acceleration B0, the reference steering angle C0, and the reference steering angular speed D0 used for the determination process in the determination means 85. Is stored. Since the output signal of the rudder angle sensor 73 corresponds to the angle at which the left axle 71 turns, the steering angle C calculated by the steering angle calculation means 82 is the steering angle C of the left axle 71. However, as described above, since the axle 71 and the rear wheel 6 turn integrally, the steering angle C of the rear wheel 6 can be said.

  The determination means 85 first determines whether or not the calculated travel speed A is equal to or higher than the reference travel speed A0, and sets a determination flag VSF related to the travel speed A to 0 or 1 as the determination result. . Second, it is determined whether or not the calculated absolute value | B | of the travel acceleration B is equal to or greater than the reference travel acceleration B0, and the determination flag VKF related to the travel acceleration B is set to 0 or 1 as the determination result. . Third, it is determined whether or not the absolute value | C | of the calculated steering angle C is equal to or greater than the reference steering angle C0, and the determination flag SKF related to the steering angle C is set to 0 or 1 as the determination result. . Fourth, it is determined whether or not the calculated absolute value | D | of the steering angular velocity D is equal to or higher than the reference steering angular velocity D0, and a determination flag SVF related to the steering angular velocity D is set to 0 or 1 as the determination result. .

  The drive control means 86 determines whether or not to lock the swing of the rear wheel suspension device 7 based on the determination flags VSF, VKF, SKF, and SVF set by the determination means 85. When it is determined that the electromagnetic control valve 14 is closed and not locked, the electromagnetic control valve 14 is opened. When the drive control means 86 determines that the electromagnetic control valve 14 is already in the closed state when it is determined to be locked, the drive control means 86 maintains the closed state as it is, and when it is determined not to lock, the electromagnetic control valve 14 is already in the open state. If so, the closed state is maintained.

  Hereinafter, the flow of control by the control device 8 will be described in more detail with reference to FIGS. 4A and 4B.

  First, as shown in FIG. 4A, the control device 8 calculates the traveling speed A based on the output signal from the rotation sensor 10 (S1), and calculates the traveling acceleration B by differentiating the traveling speed A with time ( S2). Here, the processing in S1 is the traveling speed calculation means 80, and the processing in S2 is the traveling acceleration calculation means 81. The control device 8 calculates the steering angle C based on the output signal from the steering angle sensor 73 (S3), and calculates the steering angular velocity D by differentiating the steering angle C with respect to time (S4). Here, the processing in S3 is the steering angle calculation means 82, and the processing in S4 is the steering angular velocity calculation means 83.

  Subsequently, as shown in FIG. 4A, the control device 8 compares the traveling speed A with the reference traveling speed A0 (S5). If the traveling speed A is equal to or higher than the reference traveling speed A0, the determination flag VSF is set to 1. (S6), the determination flag VSF is set to 0 (S7). Next, the absolute value | B | of the travel acceleration B is compared with the reference travel acceleration B0 (S8). If the absolute value | B | is equal to or greater than the reference travel speed B0, the determination flag VKF is set to 1 (S9). The determination flag VKF is set to 0 (S10). Further, the absolute value | C | of the steering angle C is compared with the reference steering angle C0 (S11). If the absolute value | C | is equal to or larger than the reference steering angle C0, the determination flag SKF is set to 1 (S12). The flag SKF is set to 0 (S13). Further, as shown in FIG. 4B, the absolute value | D | of the steering angular velocity D is compared with the reference steering angular velocity D0 (S14), and if the absolute value | D | Is set to 1 (S15), and the determination flag SVF is set to 0 (S16). The process from S5 to S15 or S16 is the determination means 85.

  Subsequently, as shown in FIG. 4B, the control device 8 sets the determination flag XF using the determination flag VSF related to the traveling speed A and the determination flag SKF related to the steering angle C (S17). Here, the determination flag XF is 1 when both the determination flag VSF and the determination flag SKF are 1, and is 0 when at least one of them is 0. Further, the control device 8 sets the determination flag YF using the determination flag VKF related to the travel acceleration B and the determination flag SVF related to the steering angular velocity D (S18). Here, the determination flag YF is 1 when at least one of the determination flag VKF and the determination flag SVF is 1, and is 0 when both are 0. Further, the control device 8 sets a final determination flag ZF using the determination flag XF and the determination flag YF (S19). Here, the final determination flag ZF is set to 1 when at least one of the determination flag XF and the determination flag YF is 1, and is set to 0 when both are 0. Then, it is determined whether or not the final determination flag ZF is 1 (S20). If the final determination flag ZF is 1, the electromagnetic control valve 14 is switched so as to prevent the suspension cylinder 13 from expanding and contracting, and the rear wheel suspension device is switched. 7 is prevented (S21), and if the final determination flag ZF is 0, the electromagnetic control valve 14 is switched to release the lock so that the expansion and contraction of the suspension cylinder 13 is allowed, and the rear wheel suspension device 7 is swung. (S22). Such processing from S17 to S21 or S22 is the drive control means 86, which corresponds to the switching control means of the present invention.

  According to the present embodiment as described above, it is finally determined whether the suspension cylinder 13 is locked or unlocked from the four parameters of the traveling speed A, the traveling acceleration B, the steering angle C, and the steering angular speed D. Therefore, the determination can be made under more detailed conditions, and as a result, the rear wheel suspension device 7 can appropriately control the swinging to ensure the safety of the counterbalance type forklift. Can do. And since safety | security is ensured in this way, a driver | operator can drive in comfort. In addition, since each of the above parameters is obtained by a relatively simple process and whether or not to lock is determined, it can be easily implemented.

  Further, according to the present embodiment, when at least one rotation sensor 10 and steering angle sensor 73 are provided, the traveling speed A, the traveling acceleration B, the steering angle C, and the steering angular speed D are derived. Therefore, the number of sensors can be reduced and the configuration can be simplified. If the rotation sensor 10 is provided in advance for controlling the traveling motor 9 and the steering angle sensor 73 is provided in advance for controlling the cylinder 72, the present invention is implemented without adding a new sensor. can do.

  In the above-described embodiment, the rear wheel suspension device 7 that suspends the rear wheel 5 that is a steered wheel is configured to be swingable, and this swing is restricted / released. However, the present invention has been described. Is not limited to this. For example, the front wheel 4 which is a driving wheel is supported by the vehicle body 1 via the front wheel suspension device, the front wheel suspension device is supported so as to be able to swing up and down with respect to the vehicle body 1, and the front wheel suspension device is further swung. When a swing restricting device for restricting is provided, the swing restricting device can be controlled in the same manner as described above. Moreover, the wheel suspended by the suspension apparatus supported so that rocking | fluctuation is possible may serve as a driving wheel and a steering wheel.

It is a side view of the embodiment of the present invention. It is a rear view of the embodiment of the present invention. It is a functional block diagram of an embodiment of the present invention. It is a control flow figure concerning an embodiment of the present invention. It is a control flow figure concerning an embodiment of the present invention.

Explanation of symbols

1 Car body 5 Front wheel (drive wheel)
6 Rear wheels (steering wheels)
7 Rear wheel suspension device 73 Steering angle sensor 8 Control device 80 Traveling speed calculation means 81 Traveling acceleration calculation means 82 Steering angle calculation means 83 Steering angular velocity calculation means 84 Storage means 85 Determination means 86 Drive control means 9 Driving motor 10 Rotation sensor 13 Suspension cylinder 14 Electromagnetic control valve 15 Piping

Claims (4)

The vehicle body includes a drive wheel and a steering wheel, a suspension device that is swingably provided on the vehicle body and suspends the drive wheel or the steering wheel, and a swing restriction device that restricts swinging of the suspension device. In an industrial vehicle comprising: a control device that selectively controls the swing restriction device between an operation state in which the swing of the suspension device is restricted and a non-operation state in which the restriction is released,
Speed deriving means for deriving the traveling speed of the vehicle, acceleration deriving means for deriving the traveling acceleration of the vehicle, angle deriving means for deriving the steering angle of the steering wheel, and angular velocity for deriving the steering angular speed of the steering wheel A derivation means,
First determination means for determining whether or not the travel speed is equal to or higher than a preset reference travel speed, and second to determine whether or not the travel acceleration is equal to or greater than a preset reference travel acceleration Determining means; third determining means for determining whether the steering angle is equal to or greater than a preset reference steering angle; and determining whether the steering angular speed is equal to or greater than a preset reference steering angular speed And a fourth determination means for
Further, according to the determination results of the first to fourth determining means, it is determined whether the swing restricting device is in the operating state or the non-operating state. A control device for an industrial vehicle, comprising: a switching control unit that performs control to switch to any of the states. The switching control means determines that the travel speed is greater than or equal to the reference travel speed by the first determination means, and determines that the steering angle is greater than or equal to the reference steering angle by the third determination means. It is determined that the swing restricting device is in the operating state,
When the first determining means determines that the traveling speed is not equal to or higher than the reference traveling speed, or the third determining means determines that the steering angle is not equal to or greater than the reference steering angle, 2. The industrial vehicle control device according to claim 1, wherein the swing regulating device is determined to be in the non-operating state. The switching control means determines that the travel acceleration is greater than or equal to the reference travel acceleration by the second determination means, or determines that the steering angular speed is greater than or equal to the reference steering angular speed by the fourth determination means. When it is done, it is determined that the swing regulating device is in the operating state,
When the third determination means determines that the travel acceleration is not greater than or equal to the reference travel acceleration, and the fourth determination means determines that the steering angular velocity is not greater than or equal to the reference steering angular velocity, the swing restriction The industrial vehicle control device according to claim 1, wherein the device is determined to be in the non-operating state. The switching control unit determines whether the swing restricting device is in the operating state based on the determination results of the first determination unit and the third determination unit, or the second determination unit and the fourth determination unit. When it is determined that the swing restricting device is in the operating state based on the determination result of the determining means, control is performed to switch the swing restricting device to the operating state,
Based on the determination results of the first determination means and the third determination means, it is determined that the swing restricting device is in the non-operating state, and the determination of the second determination means and the fourth determination means 4. The control according to claim 1, wherein when the swing restricting device is determined to be in the non-operating state based on a result, control for switching the swing restricting device to the non-operating state is performed. 5. The control apparatus of the described industrial vehicle.

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