JP3222735B2 - Wheelbarrow - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wheelbarrow such as a serving truck or a transport cart.

[0002]

2. Description of the Related Art Conventionally, some wheelbarrows have a function of detecting that a person is not touching an operation handle and stopping the wheelbarrow or stopping the wheelbarrow (particularly). Japanese Patent Publication No. 5-65394). In this type of wheelbarrow, for example, when the wheelbarrow is stopped in the middle of a hill, the wheelbarrow starts moving unattended due to mischief of a child, or the operator releases the operating handle when the wheelbarrow runs. The danger caused by the above is prevented by the above function, and the safety of the wheelbarrow is secured.

For this reason, in this type of wheelbarrow, a touch plate is provided on the operation handle to determine whether or not a person is touching the operation handle of the wheelbarrow, and an output signal of the touch plate is extracted. A signal circuit is provided, and the determination is made based on an output signal value of the touch plate.

[0004]

By the way, even when a person is touching the operation handle, little force is sometimes applied to the operation handle. As such a state, a case in which a person tries to maintain the wheelbarrow in a stopped state and a case in which the person tries to maintain the wheelbarrow in a constant speed motion state are considered.

[0005] Further, since the power of a person has a certain degree of fluctuation, the fluctuation is enlarged in a wheelbarrow driven based on the force of the person applied to the operation handle. However, there is a problem that the above-mentioned handcart does not consider fluctuations in the force of a person applied to the operation handle. The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a highly safe wheelbarrow.

[0006]

According to a first aspect of the present invention, there is provided an operation handle provided on a vehicle body to achieve the above object.
An external force detector for detecting a force applied to the operation handle, a wheel provided on the vehicle body, a drive source for driving the wheel, and control for controlling the drive source based on a force detection value of the external force detector a device, e Bei a timer for counting a predetermined time set in advance, the control device, the timer scan
The operation hand by the external force detector after being started
Performs processing to detect the force applied to the
The timer was reset when the specified range was exceeded.
Later, the drive source is controlled in accordance with the detected force value to
Restart the imager and the force from the external force detector
If the detected value does not exceed the specified range, the timer starts.
The timer has timed out.
When the power is not up, the
After controlling the drive source, reduce the force applied to the operation handle.
The process returns to the detection process, and the timer has expired.
The driving source so to Rutoki brakes before Symbol wheel
Detecting the force applied to the operation handle after controlling
It is you shall and features a return to the process, the timer Thailand
When the operator is not
Drive source according to the force detection value regardless of whether
There are controlled, also when the operator releases the hand during run line
Indicates whether the force detection value is almost zero and does not exceed the specified range.
When the time measured by the timer exceeds the predetermined time,
That Te detects that you have not touched the hands of the people in operations handle by which the time is up, and stops automatically
Safety can be improved.

[0007] The invention of claim 2 is the invention according to claim 1.
Te, comprising a speed detector for detecting a vehicle traveling speed, before
The control device measures the predetermined time by the timer.
When the time is up, the speed detector detects
The moving speed does not become sudden braking even if the brake is applied.
Judge whether or not the moving speed is within the moving speed range.
When the vehicle is within the enclosure, the traveling speed becomes substantially zero.
Apply the brakes to lock the wheels, and
Adding torque to the drive moving direction opposite direction when not in囲内
Following their entry into the moving speed range Te, and characterized by controlling so as to apply the brakes for moving speed locks the wheel so as to be substantially zero, it is possible to prevent sudden braking.

According to a third aspect of the present invention, there is provided an operation handle provided on a vehicle body, an external force detector for detecting a propulsion direction force or a steering direction force applied to the operation handle, a wheel provided on the vehicle body, A drive source for driving wheels, a speed detector for detecting a moving speed of the vehicle body, a control device for controlling the drive source based on a force detection value from the external force detector, and timing of a predetermined time set in advance Bei example and a timer that,
The control device , after the timer is started, the
External force detector detects the force applied to the operation handle
The force detection value exceeds the preset specified range.
After resetting the timer, respond to the force detection value.
Control the drive source and restart the timer.
And the force detected by the external force detector is within the specified range.
If not, the timer has expired
Judge whether or not the timer has timed out
Sometimes after controlling the drive source according to the force detection value
Return to the process for detecting the force applied to the operation handle
When the timer has expired,
Judges whether the speed detected by the speed detector is positive or negative.
When the value is positive, the moving speed is maintained in the same direction as the moving direction
Operating the drive source after controlling the drive source to
Returns to the process of detecting the force applied to the
When the value is set, the moving speed is maintained in the same direction as the moving direction.
After controlling the drive source to
Return to the process of detecting the applied force.
Control the drive source to stop the wheel
Returns to the process of detecting the force applied to the operation handle
If the timer has not expired
The drive source is controlled according to the force detection value.
If the time is up, the speed detected by the speed detector
Since the driving torque is generated in response can be carried out maintaining the stopped state of the wheelbarrow, the constant speed running maintained easily.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to embodiments. Wheelbarrow according to the present embodiment (Embodiment 1), as shown in FIG. 1, a vehicle body 1
An operation handle 2 for hand pushing is mounted on the vehicle body 1. A front and a rear of the lower surface of the vehicle body 1 are respectively provided with free wheels 8 and 9 capable of changing directions. A pair of wheels 4 driven by a source 5 are provided.

This wheelbarrow has a configuration as shown in FIG.
When a person touches the operation handle 2 of the wheelbarrow, the force applied to the operation handle 2 is detected by the external force detector 3, and the control device 6 uses a predetermined driving force according to the detected force value detected by the external force detector 3. The drive source 5 is controlled so as to drive the wheels 4. Here, as shown in FIG. 3, the driving source 5 drives the wheels 4 with a larger driving force as the force detection value of the external force detector 3 is larger. In this manner, the wheelbarrow requires only a small force for a person to push the wheelbarrow (hereinafter, this control method is referred to as standard control). The handcart has a timer 7. The timer 7 measures the time, and the timer expires when a predetermined time elapses after the start of the time measurement.
The control device 6 controls the drive source 5 based on the time measured by the timer 7.

For this reason, when the wheelbarrow suddenly starts moving in a state where no human hand touches the operation handle 2 (that is, a state in which the force detection value of the external force detector 3 is substantially zero). When the time measured by the timer 7 elapses a predetermined time, the control device 6 controls the drive source 5 to automatically stop the handcart (safety function). That is, in the above configuration, the control device 6, as shown in FIG. 4, for a predetermined time Delta] t _1, external force detector force detection value from 3 0 ± f ₁
If it is less (substantially zero), at time t _2, it is determined that no touch is human operation handle 2, controls the driving source 5 so as to stop the wheels 4. In the present embodiment,
Have a specified range of 0 ± f ₁ with respect to the above-described force detection value
You.

Next, the operation of the control device 6 as the gist of the present invention will be described with reference to FIG. First, when the timer 7 is started (S1), the external force detector 3 detects the external force f applied to the operation handle 2 (S2),
F stop confirmation conditions limit the absolute value preset in the control device a force detection value of the external force detector 3 in 6 f (force f) ₁
Less than whether it is determined (S3), the timer 7 is reset by the instruction from the control unit 6 when not less than f ₁ (S
4) The control device 6 determines that a human hand is touching the operation handle 2 (S5), instructs the drive source 5 to perform standard control (S6), and then returns to S1 (timer 7 Restart).

On the other hand, if the absolute value of the force detection value f detected by the external force detector 3 is less than f ₁ (S3), the control device 6 determines whether the timer 7 has expired (S3).
7) When the time is up, the control device 6 determines that no person is touching the operation handle 2 (S8), and issues a stop (braking) command to the drive source 5 to stop the rotation of the wheels 4 (S8). S9), and then return to S2.

On the other hand, when the timer 7 has not timed out, it is not possible to judge whether or not a person is holding the operation handle 2, so that an instruction is given to perform standard control (S1).
0) Then, returning to S2, the above operation is repeated. By performing the above-described control, when the operator releases the hand from the operation handle 2 of the wheelbarrow, the wheelbarrow stops automatically after a predetermined time has elapsed, so that the safety is high.

[0015] In the roller (second embodiment), the barrow of the first embodiment, when more than a certain speed value leads to a rapid deceleration when braking for stopping the wheelbarrow (sudden braking) This may cause the load of the wheelbarrow to collapse. Therefore, as shown in FIG. 6, the wheelbarrow according to the present embodiment has a speed detector 11 for detecting the moving speed of the wheelbarrow on wheels 4 in the same basic configuration as FIG. 2 described in the first embodiment. It is provided with. The feature of this wheelbarrow is that the control device 6
However, control is performed such that a brake for locking the wheel 4, for example, an electromagnetic brake (hereinafter, abbreviated as “brake”) is applied after the moving speed of the handcart detected by the speed detector 11 becomes equal to or lower than a predetermined speed.

The operation which is the gist of the present invention will be described below. In view showing a condition in which braking when stopping the wheelbarrow shown in FIG. 7, the moving speed is the -v ₀ v
_{When it is in} the range of ₀ (the hatched area in FIG. 7), it is assumed that sudden braking does not occur even when the brake is applied. On the other hand, it is assumed that when the brake is applied in a region other than the hatched region, a sudden brake is applied. In this wheelbarrow, the control device 6 determines that the absolute value of the moving speed is v ₀
If greater, the direction of travel of the wheelbarrow (ie, wheel 4
The driving source 5 is controlled so as to apply a predetermined torque T ₀ in the opposite direction to the rotation direction of the wheels 4. Then, the speed detector 1
When the moving speed detected by 1 is reduced to v ₀ or less (the speed in the hatched area), the torque applied to the wheels 4 is controlled to zero and the wheels 4 are braked.

If it is determined that braking is required in the moving speed within the shaded area (the determination method is the same as in the first embodiment), the brake is applied at that time. The operation described above will be described with reference to FIG. When the stop command to the drive source 5 from the control device 6 is issued (S21), firstly, whether exceeds a predetermined velocity v ₀ which absolute value is preset speed v detected by the speed detector 11 is determined ( S22),
v ₀ if not exceeding the control device 6 controls so as to lock the brake (S23). On the other hand, the speed detector 11
If the absolute value of the speed v detected in step ( _{1) is} larger than v ₀ (S2
2) It is determined whether or not the speed v is a positive value (S24). If the speed v is a positive value (S24), the traveling direction of the wheelbarrow (that is, the rotating direction of the wheel 4) is applied to the wheels 4. The drive source 5 is controlled so as to apply a predetermined torque −T ₀ in the opposite direction (S2).
6) Return to S22. On the other hand, when the speed v is a negative value, and controls the drive source 5 to provide a predetermined torque T ₀ to the wheel 4 (S25), the flow returns to S22.

The higher the moving speed, the more dangerous. For this reason, when the moving speed is high, a larger torque may be applied as the moving speed is higher, as shown in FIG. 9, in order to increase the degree of deceleration. The operation at this time will be described below with reference to FIG. When a stop command is issued from the control device 6 to the drive source 5 (S31), first, it is determined whether or not the absolute value of the speed v detected by the speed detector 11 exceeds a predetermined speed v ₀ (step S31). S32), v when not exceeding ₀ the control unit 6 controls so as to lock the brake (S33). On the other hand, if the absolute value of the speed v detected by the speed detector 11 is larger than v ₀ (S32), it is determined whether or not the speed v is a positive value (S34), and if the speed v is a positive value (S34). S34), giving a predetermined torque −T ₀ −αv in the opposite direction to the traveling direction of the handcart (that is, the rotation direction of the wheel 4) to the wheels 4 (where α is the amount of increase in drive torque per unit speed, In other words, the driving source 5 is controlled so as to be the inclination of the straight line in FIG. 9) (S36), and the process returns to S32. On the other hand, when the speed v is a negative value, the driving source 5 is controlled so as to apply the predetermined torque T ₀ −αv to the wheels 4 (S3).
5) Return to S22.

By performing the control based on FIG. 8 or FIG. 10, it is possible to prevent sudden braking, and as a result, it is possible to prevent collapse of the load or the like. In addition,
In the present embodiment, the electromagnetic brake has been described as the lock brake for locking the wheels 4, but the lock brake is not limited to the electromagnetic brake, and may be, for example, a brake that applies a torque in a direction opposite to the traveling direction.

(Embodiment 3 ) The basic configuration of a handcart according to the present embodiment is the same as that of FIG. 6 described in Embodiment 2, and the feature of this handcart is that the operation handle 2 A state in which a person is not touching and a state in which the person has the operation handle 2 but hardly applies a force are distinguished. In the latter state, the person moves the wheelbarrow at a constant speed (stop, that is, zero speed). Is determined, and the driving source 5 is controlled so as to maintain the constant-velocity motion.

When a person has the operation handle 2 but does not apply any force, the force of the person fluctuates.
The time change of the force detection value has, for example, a waveform as shown in FIG. 11 and is not a weak vibration as shown in FIG. 4 of the first embodiment (f ₂ > f ₁ ). Therefore, a state in which a person does not hold the operation handle 2 due to a change in the amplitude width of the force detection value (f <f
₁ ) and a state in which a person has the operation handle 2 but does not apply force (f <f ₂ ) . What
In the first embodiment, the specified range is 0 ± f ₁ .
However, in the present embodiment , the specified range is 0 ± f ₂ .

In the case of the latter determination, the controller 6 controls the moving speed v so as not to change the current moving speed v as shown in FIG.
A driving torque command corresponding to the moving speed v as shown in FIG. Here, when the moving speed v is substantially zero, the driving torque command is zero. In other cases, the absolute value of the driving torque increases as the absolute value of the moving speed v increases.

By the way, the method of giving the driving torque is as follows.
As the moving speed v increases like the rolling resistance,
This is the case where the resistance increases. Therefore, when the resistance due to the moving speed v hardly changes or when it is not necessary to consider it, a constant driving torque may be applied as shown by the broken line in FIG. That is, a constant torque is applied in the same direction as the moving direction (when the moving speed v is substantially zero, the driving torque is also zero). Further, when the moving speed v is substantially zero, the wheels 4
Turn on the brake to lock the.

Next, the above operation will be described with reference to FIG. First, when the timer 7 is started (S20)
1) The external force f is detected by the external force detector 3 (S20).
2), the force detection value f of the external force detector 3 (that is, the external force f)
It is determined whether the absolute value of f is less than f ₂ (S203), and f
_If not less than ₂ (that is, not less than f ₂ ), the timer 7 is reset (S204), and standard control is performed (S205).
It returns to S201.

On the other hand, if the absolute value of the force detection value f is less than f ₂ (S203), it is determined whether or not the timer 7 has timed out (S206). It is determined that the current speed is maintained (S2
07). Next, if the current moving speed v is positive (that is, the wheel 4
Is determined to be a normal rotation) (S208).
If the value is not a positive value, it is determined whether the value is a negative value (that is, the wheel 4 is rotating in reverse) (S209). When the moving speed v is not a negative value (that is, when the moving speed v is substantially zero), the control device 6 issues a stop command to the drive source 5 (S21).
2) Then, the process returns to S202.

On the other hand, when the moving speed v is a positive value (S208), and commanded to generate the driving torque T ₁ in the same direction as the traveling direction to the drive source 5 (S210), then returns to S202 . On the other hand, when the moving speed v is a negative value (S209), the driving torque
₁ (S211), and then S2
Return to 02. Here, T ₁ is a value obtained from Figure 12.

On the other hand, when the timer 7 has not timed out (S206), it is not known whether or not a person is holding the operation handle 2 so that standard control is performed (S213), and thereafter, the process returns to S202. By performing the above-described control, it is possible to easily maintain the stopped state of the handcart and maintain the constant speed traveling.

[0028]

According to the first aspect of the present invention , there is provided an operation device provided on a vehicle body.
Handle for detecting the force applied to the handle and the operation handle.
A force detector, wheels provided on the vehicle body, and driving the wheels
Based on the drive source to be driven and the force detection value of the external force detector
A control device for controlling the drive source, and a preset predetermined time
A timer for measuring the time between the two .
The operation by the external force detector after the
Performs processing to detect the force applied to the handle and detects the force.
If the value exceeds the specified range, the timer is reset.
Control the drive source according to the detected force value
Restarting the timer, and the external force detector
If the force detection value does not exceed the specified range,
Determines whether the time has expired,
If the time is not up, respond to the force detection value.
After controlling the drive source,
The process returns to the process of detecting the force
The brakes on the wheels when
After controlling the drive source, reduce the force applied to the operation handle.
Since the process returns to the detection process, the timer has expired.
When the operator is not
The drive source is controlled according to the force detection value regardless of
If the operator releases the hand while traveling, the force detection
Since it becomes zero and does not exceed the specified range,
The time is up after the specified time has elapsed.
Detects that you have not touched the hand of man to the operation handle by Rukoto, can be stopped automatically, enhance safety
There is an effect that can be .

[0029] The invention of claim 2 is the invention according to claim 1.
Equipped with a speed detector for detecting the moving speed of the vehicle body,
The control device measures the predetermined time by the timer.
When the time is up, the speed detector detects
The moving speed does not become sudden braking even if the brake is applied.
Judge whether or not the moving speed is within the moving speed range.
When the vehicle is within the enclosure, the traveling speed becomes substantially zero.
Apply the brakes to lock the wheels, and
Adding torque to the drive moving direction opposite direction when not in囲内
Movement following their entry into the speed range, and controls so as to apply the brakes for moving speed locks the wheel so as to be substantially zero Te, there is an effect that it is possible to prevent sudden braking.

According to a third aspect of the present invention , there is provided an operation handle provided on a vehicle body.
Dollar and the force in the propulsion direction applied to the operation handle or
Is installed on the vehicle body with an external force detector that detects the force in the steering direction.
A gear wheel, a drive source for driving the wheel, and the vehicle body
A speed detector for detecting the moving speed of the external force detector;
Control device for controlling the drive source based on the detected force values
And a timer that measures a predetermined time set in advance,
The control device, after the timer is started, the
External force detector detects the force applied to the operation handle
The force detection value exceeds the preset specified range.
After resetting the timer, respond to the force detection value.
Control the drive source and restart the timer.
And the force detected by the external force detector is within the specified range.
If not, the timer has expired
Judge whether or not the timer has timed out
Sometimes after controlling the drive source according to the force detection value
Return to the process for detecting the force applied to the operation handle
When the timer has expired,
Judges whether the speed detected by the speed detector is positive or negative.
When the value is positive, the moving speed is maintained in the same direction as the moving direction
Operating the drive source after controlling the drive source to
Returns to the process of detecting the force applied to the
When the value is set, the moving speed is maintained in the same direction as the moving direction.
After controlling the drive source to
Return to the process of detecting the applied force.
Control the drive source to stop the wheel
Returns to the process of detecting the force applied to the operation handle
So if the timer has not timed out, force detection
The drive source is controlled according to the value, and the timer
Drive in accordance with the speed detected by the speed detector
Since the torque is generated, there is an effect that the stop state of the handcart and the maintenance of the constant speed running can be easily performed.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a first embodiment of the present invention.

FIG. 2 is a block diagram of Embodiment 1 of the present invention.

FIG. 3 is an explanatory diagram illustrating a relationship between a force detection value and a driving force command value.

FIG. 4 is a diagram illustrating an example of a temporal change of a force detection value.

FIG. 5 is an operation explanatory diagram of the first embodiment of the present invention.

FIG. 6 is a block diagram according to a second embodiment of the present invention.

FIG. 7 is a diagram showing conditions for applying a brake when stopping a handcart.

FIG. 8 is an operation explanatory diagram of Embodiment 2 of the present invention.

FIG. 9 is an explanatory diagram showing a relationship between a detected force value and a driving force command value.

FIG. 10 is an operation explanatory diagram according to the second embodiment of the present invention.

FIG. 11 is a diagram showing an example of a temporal change of a force detection value.

FIG. 12 is an explanatory diagram showing a relationship between a moving speed and a driving force torque.

FIG. 13 is an operation explanatory diagram of the third embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Body 2 Operation handle 3 Force detector 4 Wheel 5 Drive source 6 Control device 7 Timer 8 Free wheel 9 Free wheel

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-4-129872 (JP, A) JP-A-6-22157 (JP, U) JP-B-5-65394 (JP, B2) (58) Field (Int.Cl. ⁷ , DB name) B62B 3/00 B62B 5/04 B62B 5/06

Claims (3)

(57) [Claims] An operation handle provided on a vehicle body, an external force detector for detecting a force applied to the operation handle, a wheel provided on the vehicle body, a driving source for driving the wheel, and an external force detector e Bei a control device for controlling the drive source on the basis of the force detection value, a timer for counting a predetermined time set in advance, the control device, the timer is started
From the external force detector
Performs processing to detect the applied force, and makes the force detection value a preset rule.
If the specified range is exceeded, the force will be reset after resetting the timer.
The timer is restarted by controlling the driving source according to the detected value.
And the force detected by the external force detector is
If the value does not exceed the specified range, the timer expires.
The timer expires.
If not, the drive source is controlled according to the detected force value.
The force applied to the operating handle after the
When the timer has expired,
After controlling the driving source so brake the front SL wheels
Returns to the process of detecting the force applied to the operation handle
A wheelbarrow characterized by that . 2. A control device comprising a speed detector for detecting a moving speed of a vehicle body, wherein the control device controls the predetermined time by the timer.
When the time is up and the time is up, the speed detector
If the moving speed detected by the
Judge whether it is within the moving speed range where
When it is within the moving speed range, the moving speed will be almost zero
Apply the brakes to lock the wheels
Following their entry into the moving speed range by adding torque to the drive moving the opposite direction when not in movement speed range, so as to brake for moving speed locks the wheel so as to be substantially zero The wheelbarrow according to claim 1, wherein the wheelbarrow is controlled. 3. An operation handle provided on a vehicle body, an external force detector for detecting a force in a propulsion direction or a force in a steering direction applied to the operation handle, a wheel provided on the vehicle body, and a drive for driving the wheel a source, a speed detector for detecting a moving speed of the vehicle body, and a control device for controlling the drive source on the basis of the force detection value from the external force detector, preset
E Bei a timer for counting a predetermined time, said control device,
From the external force detector after the timer is started
Performing a process of detecting a force applied to the operation handle,
When the force detection value exceeds a predetermined range, the timer
After resetting the drive source according to the force detection value.
Control to restart the timer, and
If the force detection value by the detector does not exceed the specified range
Determine whether the timer has expired, and
When the timer has not timed out, the force is detected.
After controlling the drive source according to the value, the operation handle
The process returns to the process of detecting the force applied to the
Is detected by the speed detector
Judges whether the speed is positive or negative, and moves when the detected speed is a positive value
Drive to maintain the moving speed in the same direction as
Detects the force applied to the operating handle after controlling the source
Return to the processing of
Drive source so as to maintain the moving speed in the same direction as
Detecting the force applied to the operation handle after controlling
Return to processing, stop wheel if neither positive or negative
After controlling the drive source to
A wheelbarrow characterized by returning to a process for detecting an applied force .