JPS6146760A - Driving controller for truck having power - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a drive control device for a motorized truck.

(Prior Art) Conventionally, various types of operating devices for powered trolleys have been put into practical use. These devices include those that use a joystick to control the speed and direction of the powered cart, and those that have an operating grip similar to the accelerator on a motorcycle and control the running speed by rotating it. etc.

(Problem to be solved by the invention) However, with conventional methods such as this, which use a joystick or rotate the operating grip, it requires considerable skill to operate, and anyone can operate it easily. The problem was that I couldn't do it.

(Means for Solving the Problems) Therefore, the present invention provides a measuring device for individually measuring the force applied to a cart by a worker at at least two positions, and each measurement value from this measuring device. A motorized bogie is constructed by a calculation device for individually calculating acceleration/deceleration according to the acceleration/deceleration based on the calculated values, and a drive device for individually driving two motors based on the respective calculation values from this calculation device. The present invention is characterized in that a drive control device is configured.

(Example) Hereinafter, the present invention will be specifically described based on an example shown in the drawings.

First, the first embodiment will be described. FIG. 2 shows the overall structure of the powered truck 1. As shown in FIG. In this example, the powered trolley 1 is formed into a rectangular parallelepiped shape, and a hand bar 2 is attached to a side surface 1a of the powered trolley 1 via a support rod 2a. On the other hand, two drive wheels 3 and 4 are provided at the rear of the lower surface of the powered truck 1.
, and one front wheel S is provided near the center of the front portion of the lower surface.

Next, the control circuit 25 for controlling the rotation of the drive wheels 3 and 4 will be explained based on FIG. First, the above-mentioned 2
Strain gauges 5, 5 are provided on the two support rods 2a, 2a, respectively. This consists of, for example, a resistance wire strain gauge, and is attached to the support rods 2a, 2a, respectively.

In this example, the support rods 2a, 2a are given some flexibility in order to generate sufficient strain on the strain gauge 5.5.

The signal from the strain gauge 5.5 is sent to an A/D converter 6.5.
7 to the CPtJ8. CPU
Reference numeral 8 denotes a normal 8-bit microcomputer, to which a RAM 9 and a ROM 10 are connected. The ROM 10 has a built-in control program for controlling the entire control circuit 25. Note that this control program will be described later.

Next, there are two D/D ports on the output side of the CPLJ8.
Al inverters 11 and 12 are connected, and one of the D/A converters 1 and 12, the D/A converter 1, is a drive control unit 13 for driving the drive motor 6.
The other D/A converter 2 is connected to a drive control device 15 for driving the drive motor 8.

The drive motor 6.18 is a normal DC type servo motor heater, and is driven and controlled by the output current from the drive control device 13.15.

On the other hand, the drive motors 16 and 18 each have a drive wheel 3.
, 4, brake 20.27, and speed sensor 17.19
and is provided.

The speed sensors 17 and 19 are each composed of a tacho generator or the like, and each outputs a voltage proportional to the rotational speed of the drive motor 16.18. and,
The output signals from these speed sensors 17 and 19 are A
The analog signal is converted into a digital signal by the /D converter 11.28 and then input to the CPtJ8.

The brakes 20, 27 are for stopping the rotation of the drive motor 16.degree. 18, and are controlled to be turned on or off by signals from the CPU 8 and the emergency stop switch 23.

Next, the start switch 21, stop switch 22, and emergency stop switch 23 will be explained. The start switch 21 is a switch for simultaneously supplying current to the 1lJt[1 circuit 25 and resetting the CPU, etc. When turned on, current is supplied to each circuit and CPtJ8 is reset. and a predetermined program is executed.

The stop switch 22 is for applying a brake to the powered truck 1, and when it is turned on, an interrupt is generated and the interrupt process shown in FIG. 7 is executed.

The emergency stop switch 23 is a switch for sending an emergency stop signal to the CPU 8, the drive control devices f13, 15, and the brakes 20 and 27. When this switch is turned on, it immediately turns off the drive control devices 13, 15. , brake 2
It has the function of operating 0.27 and holding CPtJ8. This emergency stop switch 23
Since the brake can be applied directly without going through the CPU 8, safety in the event of an emergency is increased.

Next, the action and effect will be explained. First, the basic control pattern in this example will be explained based on FIG.

First, as a first pattern, when the output from the strain gauge 5 is O, it is determined that it is a stop condition, and the acceleration and vehicle speed are set to O to stop the powered truck 1.

Next, as a second pattern, when the output from the strain gauge 5 is 10 (that is, when the hand bar 2 is pushed forward) and the rotational speed of the drive wheels 3 and 4 is 0, the start is started. It is determined that the condition is met and the acceleration instruction is set to 10. Therefore, the speed of the powered truck 1 will gradually increase from O.

As a third pattern, when the output from the strain gauge 5 becomes O while the powered truck 1 is traveling at a predetermined speed, a slight deceleration instruction is issued. This corresponds to the fact that, for example, if you release your hand while pushing a light trolley, the trolley will move forward while slowly decelerating.

As a fourth pattern, when the output from the strain gauge 5 becomes ten while the powered trolley 1 is running at a predetermined speed,
It determines that the acceleration condition is met and gives an acceleration instruction.

As the fifth pattern, when the output from the strain gauge 5 becomes negative while the powered trolley 1 is running at a predetermined speed (that is, when the hand bar 2 is pulled backward), deceleration occurs. It is determined that the condition is the condition f1, and deceleration is performed.

The above is the basic acceleration instruction pattern in this example.

However, since the backward movement control of the powered truck 1 is the same as the forward movement control described above, the explanation thereof will be omitted here.

Next, specific details of the control will be explained based on the flowchart shown in FIG.

First, when a power switch (not shown) of the control circuit 25 is turned on, the main routine shown in FIG. 4 written in the ROM10 starts.

When this routine starts, first, in step 100, the initial settings (initialization) of each part are performed, and the brakes 20 and 27 are turned on to prevent the motorized truck 1 from running carelessly. When this is completed, in step 101, the start switch 21 becomes input. When the start switch 21 is turned on here, the process proceeds to step 102, where the brakes 20 and 27 are turned off to enable driving, and the drive control device 13
．． Turn on 15.

When this is completed, the process proceeds to timer processing 103 and waits for a predetermined time. This step 103 is a timer routine for determining the cycle of the main routine, and
This makes it possible to set the sampling time for data from the strain gauge 5.5.

When the waiting time in step 103 ends, step 1
The process advances to step 04, where data is input from the strain gauges 5,5. The data input from this strain gauge 5.5 is converted from analog to digital by A/D converters 6 and 7, respectively, and then input to CPtJ8, where it is converted into stress based on a predetermined program (this step 105) is performed.

When the process in step 105 is completed, step 106
Then, the rotational speeds of the left and right driving wheels 3 and 4 are input from the speed sensors 17 and 19 of the left and right driving wheels 3 and 4, respectively. Then, when this input is completed, step 10
The process advances to step 7 to calculate acceleration. This step 1
In the calculation of acceleration in step 07, in this example, the velocity data sampled this time is subtracted from the velocity data sampled last time to find the change in acceleration per unit time.

Once this acceleration has been calculated, the process proceeds to step 108, where it is determined whether the rotational speeds of the drive wheels 3 and 4 are O or not.

Here, if both rotational speeds are O, the process proceeds to step 109, and if the rotational speeds are not O, the process proceeds to step 111.

In both step 109 and step 111, the strain gauge 5.
5, it is determined whether the detected stress is 0 or in the dead zone. Here, the dead zone is the fifth
As shown in the figure, within a range where the force applied to the strain gauge 5.5 is extremely small, the output from the strain gauge 5.5 is considered to be O.

If the determinations at step 109 and step 111 are No, the process advances to step 113 and the step 1
The acceleration/deceleration according to the stress found in 05 is ROMl
The drive motors 16 and 18 are each read out from the map set within 0 and based on this
It has become like this.

Here, to explain the map in the ROM 10 referred to in step 113, it is as shown in FIG.
When a stress exceeding a predetermined value is applied, an acceleration or deceleration approximately proportional to this stress is indicated. (In other words, data having such a predetermined correspondence relationship is written as data in the ROM 10.) On the other hand, if the determination at step 109 is YES, the process advances to step 110 and the drive is started. After the acceleration instruction for the motors 16 and 18 is set to 0, the process returns to step 103.

If the determination in step 111 is YES, the process advances to step 112 to read out the acceleration/deceleration corresponding to the current rotational speed of each of the drive motors 6 and 18 from the map set in the ROM 10. Based on this, the number of rotations of the drive motor 6.18 is set to IIIall.

Here, the map in the ROM 10 referred to in step 112 is as shown in FIG. 6, and is designed to indicate acceleration/deceleration approximately proportional to the rotational speed of the drive motor 6.18. However, the acceleration/deceleration instruction in step 112 corresponds to, for example, a case where the operator stops pushing the powered trolley 1 while the vehicle is running, so it is similar to the gradual deceleration of a lighter trolley. The deceleration is now very gradual. When the process at step 112 is completed, the process returns to step 103 and the same process as described above is repeated.

In this way, in this main routine, the drive motor 6
．． This means that 18 tiIIItl are performed.

Here, to explain the correspondence between the control pattern shown in FIG. 3 and the 70-chat shown in FIG. 4, in the stopped state shown in the first pattern, step 108, The process proceeds to step 109, step 110, and then returns to step 103.

At the start shown in the second pattern, the process proceeds to step 108, step 109, step 113, and then returns to step 103.

Next, in the running state shown in the third pattern, the process proceeds to step 108, step 111, step 112, and then returns to step 103. Next, the fourth
At the time of acceleration control shown in the second pattern, step 10
8, step 111, step 113, and then returns to step 103.

Further, during deceleration control shown in the fifth pattern, the process returns to step 103 from step 108, step 111, and step 113.

Subsequently, stop switch 22 or emergency stop switch 2
The control when 3 is turned on will be explained.

First, when the stop switch 22 is turned on, an interrupt occurs, and the control of the main routine shown in FIG. 4 is temporarily interrupted, and at the same time, the interrupt processing shown in FIG. 7 is started.

In this interrupt processing, first, in step 201, a timer is turned on. This is to prevent waiting time from occurring in step 202 when the first interrupt processing starts. When this step 201 is finished, step 2 is started immediately from step 202.
03, it is determined whether the rotational speeds of the drive wheels 3 and 4 are within the speed range at which the brakes can be applied.

To explain the determination at step 203 in detail, a map as shown in FIG. 8 is set in the ROM 10. In this map, when the rotational speeds of drive wheels 3 and 4 are both in the range of 1■1 to ■1, it is determined that the brake is at a speed that does not cause sudden braking even if the brake is applied at IJs 4, and the brake is set at 20.27. It is designed to apply the brakes by turning it on.

On the other hand, the rotational speed of drive wheels 3 and 4 is greater than or equal to ■1 or -■1
If the speed is below, it is determined that the speed is such that sudden braking will occur if the brakes are applied, and the system instructs acceleration or deceleration according to the rotational speed of the driving wheels 3 and 40. That is, for example, when the rotational speed of the drive wheels 3 or 4 is v2, a negative acceleration α2 is instructed.

The part explained above will be explained based on the flowchart shown in FIG. 7. If the judgment in step 203 is YES
In this case, the rotational speed is within the safe range even if the brake 20.27 is turned on, so proceed to step 205, turn off the drive control device 13.15, turn on the brake 20.27, and then turn on the brake 20.27. After resetting the timer in step 206, the process returns to the main routine shown in FIG.

On the other hand, if the determination in step 203 is No, that is, the driving wheel 3 or 40 rotation speed is the brake 20 or 2 rotation speed.
If the rotational speed is not within the speed range in which rotational speed 7 can be turned on, the acceleration/deceleration corresponding to the rotational speed is read out from the ROM 10 and instructed.

When the process in step 204 is completed, the process returns to step 202 and the same process is repeated until the rotational speed of the driving wheels 3 and 4 reaches a speed range where the brake can be turned on. Once the speed range is reached, step 205 and step 2 are performed as described above.
The program proceeds to 06, turns on the brakes 20 and 27, and then returns to the main routine.

Next, control when the emergency stop switch 23 is turned on will be explained. When this emergency stop switch 23 is turned on, this switch directly controls the drive control device 13.
．． 15 is turned off, brake 1-key 20, 27
is turned on, and the CPU 8 is placed in a hold state. Since the stop processing by the emergency stop switch 23 is directly performed by hardware without going through the CPU 8, safety in an emergency is enhanced.

Through the above-described control, in this example, the powered trolley 1 is moved while pushing the hand bar 2 with the hand in the same way as a normal trolley, resulting in a state similar to pushing a very light trolley. You can carry your luggage etc.

Next, a second embodiment shown in FIG. 9 will be described. In addition to the functions of the first embodiment described above, this second embodiment has a function of stopping the motorized cart 1 by the same process as when the stop switch 22 is turned on when the hand bar 2 is released. is added. Next, it will be explained in detail.

First, as shown in FIG. 9, a metal touch plate 24 is provided on the hand bar 2 of the powered trolley 1 so as to wrap around the side surface thereof. Therefore, this touch plate 24 is equipped with a C for amplifying the weak voltage from now on.
- Connected to CPtJ8 via a sense amplifier 26 made of MOS IC or the like. Note that the other configurations are the same as those in the first embodiment, so explanations will be omitted. (
In order to simplify the explanation, FIG. 9 only shows the part mainly including the sense amplifier 26, and other parts are omitted. ) Next, the operation and effect will be explained based on the flowchart shown in FIG. First, when the touch plate 24 is removed from the touch plate 24, the CPtJ8 detects the loss of the signal from the sense amplifier 26 and generates an interrupt. Then, the routine shown in FIG. 10 starts, and first, in step 300, an interrupt caused by turning on the touch plate 24 is permitted, and in step 301, a timer is turned on, and then the process proceeds to step 302.

Step 302 is a timer routine for determining the control cycle, and since the timer is initially turned on in step 301, the process immediately proceeds to step 303, and in this step 303, the current state of the drive wheels 3 and 4 is It is determined whether both rotational speeds are within a speed range in which the brakes 20.degree. 27 can be turned on. If the answer is YES, the process proceeds to step 305, and if the answer is no, the process proceeds to step 304, where the acceleration corresponding to the current rotational speed of the drive wheels 3 and 4 is output, and then the process returns to step 302.

The map referred to in steps 303 and 304 is the same map shown in FIG. 8 as used in the interrupt processing by the stop switch 22 described above.

On the other hand, if the determination in step 303 is YES, the process proceeds to step 305, where the interrupt routine caused by turning on the touch plate 24 is masked, and the process proceeds to step 306, where the drive control device 13.15 is turned off and the brake 20.27 is turned off.
is turned on, the timer is reset in step 307, and the process returns to step 100 of the main routine shown in FIG.

The above processing describes the interrupt processing when the hand is removed from the touch plate 24, but even if the hand is removed from the touch plate 24, the touch plate 24 is not grasped again before the motorized cart 1 stops. If so, you need to return to normal processing.

Therefore, in this example, in addition to the above-mentioned interrupt routine,
An interrupt routine is provided when the touch plate 24 is turned on as shown in the figure.

To explain this, when a hand touches the touch plate 24, an interrupt occurs and the routine shown in FIG. 11 starts. In this routine, in step 400, the interrupt routine is first masked so that no interrupt occurs due to the touch plate 24 being turned on during processing of this routine, and then in step 401, the timer is reset, and then the interrupt routine is masked as shown in FIG. Main routine step 103
It is now possible to proceed to That is, this is a network in which normal acceleration or deceleration processing is performed by moving the processing to step 103 of the main routine.

In this way, in this second embodiment, when the hand bar 2 is removed, the motorized cart 1 can be automatically stopped in the same way as by operating the stop switch 22 once.

Therefore, whenever the hand bar 2 is removed from the hand, the stop processing is performed, which further improves safety. Note that other processes are the same as those in the first embodiment, so explanations will be omitted.

Next, a third embodiment will be described. In the third embodiment, whereas in the first embodiment the accelerations of the drive wheels 3 and 4 were calculated from the rotational speeds of the drive wheels 3 and 4, (in the first embodiment, in step 107 of the main routine) , the acceleration is calculated from the difference between the previous speed and the current sampling speed) The acceleration of the drive wheels 3 and 4 is directly determined using the A/D converters 31 and 32, and predetermined control is performed based on this. ing.

Therefore, in this third embodiment, as shown in FIG.
/D converters 31 and 32 and accelerometers 29 and 30 are newly provided to the control circuit 25 (in FIG. (Only the CPU 8 is shown and other circuits are omitted.) Also, step 107 of the main routine shown in FIG.
The acceleration input is from converters 31 and 32.

In this way, in this third embodiment, since the acceleration is determined by hardware using the Δ/D converters 31 and 32, calculation time for determining the acceleration is not required, and therefore data with higher precision can be obtained faster. It has the characteristic of being able to increase the viscosity of control.

(Effects of the Invention) As detailed above, in the present invention, the force applied to the hand bar is measured and the drive motor is driven and controlled based on this applied force. It has the excellent feature of being able to be operated as if lightly pushing a light handcart, without the need for the hassle of driving a motorized trolley at all.

Therefore, it does not require any skill to operate, and anyone can operate it easily, and there are no problems such as the powered cart flying out or stopping suddenly due to unfamiliar operation.

Furthermore, the structure is such that the force applied to the powered cart by the worker is measured individually at at least two locations, and the acceleration/deceleration is determined from each measurement value to drive the separately provided drive source. A feature of this system is that it is extremely easy to steer the powered cart in the left and right directions.

[Brief explanation of the drawing]

The drawings show embodiments of the present invention; FIG. 1 is a block diagram showing a first embodiment of the control circuit, FIG. 2 is a perspective view of a powered truck, and FIG. An explanatory diagram showing the patterns of each running state of the powered trolley depending on the signal and the rotational speed of the drive wheels, Fig. 4 is a flowchart showing the first embodiment of the main routine set in the ROM, and Fig. 5 is a hand bar. Figure 6 is a diagram showing the relationship between the stress applied to the hand bar and the acceleration determined by the stress, and Figure 6 shows the acceleration at the speed of each drive wheel in order to gently stop the powered truck when the stress on the hand bar reaches O. Figure 7 is a flowchart of the interrupt routine when the stop switch is turned on, Figure 8 is a diagram showing the braking conditions when stopping the powered truck, and Figure 9 is a diagram showing the braking conditions for stopping the powered truck. J block diagram showing the main parts of the control circuit, Figure 10 is the second
FIG. 11 is a flowchart showing the interrupt routine when the touch plate is turned on in the embodiment; FIG. 11 is a flowchart showing the interrupt routine when the touch plate is turned off;
The figure is a block diagram showing the main parts of the control circuit in the third embodiment, and FIG. 13 is a flowchart showing changes in the main routine in the third embodiment. 1... Powered trolley 2... Hand bar 3.4... Drive wheel 5... Strain gauge 6゜7, 14.28, 31.32... AID converter 8... CPU 9...RAM 10...ROM 13.15...Drive control device 16.18...Drive motor 17.19...Speed sensor 20.27...Brake 21...Start switch 22. ... Stop switch 23 ... Emergency stop switch 24 ... Touch plate 25 ... Control circuit 26 - ... Sense amplifier 29.30 ... Accelerometer Applicant Toyota Industries Corporation Agent
Patent Attorney Oka 1) Hidehiko Figure 13 Figure 7 Figure 9II! 8th WJ 11 10th Cabinet

Claims (1)

[Claims] A drive control device for a powered trolley having at least two individual drive sources consisting of motors, the measuring device for individually measuring the force applied to the trolley by an operator at at least two positions. , an arithmetic device for individually calculating corresponding acceleration/deceleration based on each measured value from this measuring device, and an arithmetic device for individually driving each of the motors based on each calculated value from this arithmetic device. 1. A drive control device for a powered truck, comprising: a drive device for driving a motorized truck;