JP3359022B2 - Cargo handling vehicle - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cargo handling vehicle that can be used in both a walking type and a riding type.

[0002]

2. Description of the Related Art There are cargo handling vehicles having both functions of a walking type in which an operator operates while walking and a riding type in which an operator gets on and operates. More specifically, the cargo handling vehicle is divided into a vehicle body and a lifting / lowering unit, and the vehicle body includes a steering mechanism, a traveling motor, steering drive wheels and the like driven by these, and the lifting / lowering unit is a front part of the vehicle body. And comprises a battery accommodating portion accommodating a battery and a mounting table located at the front of the battery accommodating portion.

[0003] The vehicle body is provided with an operation handle capable of swinging in the left-right direction and the up-down direction, and an accelerator, an up / down button, an alarm button, and the like are arranged at a top portion of the operation handle. The operation handle is capable of steering the steering drive wheel by swinging in the left and right directions, and performs braking and brake release by swinging in the up and down directions. The elevating button allows the elevating unit to be moved up and down.

[0004] A step is provided at the rear of the body of the cargo handling vehicle for selectively determining whether the operator walks or gets on the vehicle. The step is foldable, and at the time of storage, while taking a vertical posture toward the vehicle body side,
Take horizontal position when using. That is, when the step is stored, the step is used as a walking type, and the operator holds the operation handle and walks to operate the vehicle by pulling the vehicle with the step side as the forward direction. In addition, when the step is used, the vehicle is used as a riding type, and the operator drives the vehicle with the elevating unit side in the forward direction while riding on the step.

[0005] Focusing on the speed control of the cargo handling vehicle, the vehicle travels when the accelerator disposed on the operation handle top is rotated, and a traveling speed corresponding to the accelerator angle is set in advance. ing. That is, in the conventional speed control of the cargo handling vehicle, if the accelerator amount is the same regardless of whether the operator uses the walking type or the riding type, the traveling speed is in accordance with the accelerator amount. Is a single-stage traveling control that becomes one traveling speed curve with respect to the change of the vehicle speed.

[0006]

The above-described single-stage traveling control has the following problems. In other words, the cargo handling vehicle has two uses, a walking type and a boarding type. Considering the case where the vehicle is used as a riding type, a high-speed running to some extent is required in order to improve the movement efficiency of the vehicle and the efficiency of the cargo handling work. The maximum speed is set to be able to. When this is viewed in terms of the accelerator amount, the running speed becomes 0 without the accelerator amount, and the running speed becomes the maximum speed (for example, 7 km / h) when the accelerator amount is the highest. Thus, speed control suitable for traveling as a riding type can be realized.

However, if the speed control suitable for the riding type is used, there is a problem that when the cargo handling vehicle is used as a walking type, it does not match a human walking speed (for example, 4 to 5 km / h). . That is, when the operator drives the vehicle while walking, the operation is performed while pulling the vehicle with the operation handle. However, when the accelerator amount is erroneously increased, the speed of the vehicle is higher than the walking speed. Therefore, there is a danger that the vehicle approaches or hits the operator.

Therefore, the speed control of the cargo handling vehicle is speed control (for example, when the maximum speed is 4
Speed control set to 〜5 km / h) can be considered. However, in this case, a problem occurs when the vehicle is used as a riding type. In other words, if the vehicle is only at the walking speed of a human at the time of use as a riding type, the moving efficiency of the vehicle is deteriorated, and the efficiency of the cargo handling work is also deteriorated.

Accordingly, it is an object of the present invention to enable speed control suitable for a walking type and a riding type.

[0010]

In order to achieve the above object, the present invention provides a battery as a driving source, a driving wheel for rotation driven by electric power from the battery, and a traveling speed by the driving wheel. A speed control means for controlling, a cargo handling vehicle having a mounting table for loading the load, the vehicle is provided with a step for an operator to board,
And the speed control means includes accelerator means for controlling the traveling speed by the operation of the operator, and switching means for switching the traveling speed controlled by the accelerator means to a plurality of stages. Features.

Further, the switching means switches the maximum speed of the vehicle body controlled by the speed control means to a plurality of speeds.

The switching means has a detector for detecting the presence or absence of an operator on the step, and controls the speed control by the speed control means when the operator is not on the step based on the detection result of the detector. It is characterized by switching to a low speed side.

[0013] Further, the invention is characterized in that the step is provided so as to be able to move out and into the vehicle body.

Further, the switching means has a detector for detecting the exit of the step, and based on the detection result of the detector, when the step retreats to the vehicle body, the speed control by the speed control means. Is switched to a lower speed side.

In addition, the step is provided rotatably so as to take a horizontal posture and a vertical posture with respect to the vehicle body, and is urged to assume a vertical posture by urging means.
The switching means has a detector for detecting the turning in the step, and switches the speed control by the speed control means to a lower speed side when the step takes a vertical posture based on a detection result of the detector. There is a feature.

The switching means has a manual switching switch provided on the vehicle body, and switches the speed control by the speed control means based on a switching operation of the switch.

Further, the cargo handling vehicle is a low-lift truck using the drive source as a battery.

[0018]

Embodiments of the present invention will be described below. 1 to 8 show a first embodiment. Referring to FIG. 1, the cargo handling vehicle of the present invention is divided into a vehicle body 13 and a lifting unit 14. The vehicle body 13 includes a steering mechanism, a traveling motor 23, and steering drive wheels 3 driven by the steering mechanism and the traveling motor 23.
The elevating unit 14 is located at the front of the vehicle body 13 so as to be able to go up and down, and is located at the front of the battery housing 15 in which the battery is housed and the front of the battery housing 15 for loading a load. It is composed of a mounting table 5 for mounting. The traveling motor 2
Reference numeral 3 drives using the battery as a power source to rotate the steering drive wheel 3.

An operation handle 1 is mounted on the upper part of the vehicle body 13. On the top of the operation handle 1, an accelerator 16 and an elevating button (elevating button 17, elevating button 18) for elevating the elevating part 14 are provided. ), An operation mechanism such as an alarm button for emitting an alarm sound is centrally arranged (see FIG. 2). The operation handle 1 is capable of swinging in the left-right direction, and the steering drive wheel 3 is steered. In addition, the operation handle 1 is also capable of swinging up and down about the shaft 2 to perform brake and brake release.

At the rear of the vehicle body 13, a step 4 is rotatably supported. Reference numeral 10 denotes a stopper, the back surface of which contacts the end of the step 4 and the front surface of which
1 downward. Thereby, step 4 can take the horizontal posture B while having elasticity,
This realizes a good ride comfort even when traveling on an uneven road surface or the like. The step 4 has a shaft 7 serving as a rotation axis at the base, and is urged to always return to the vertical posture A by a spring 9 wound around the shaft 7.
Therefore, when the operator descends from Step 4, Step 4 returns to the vertical posture A by the force of the spring 9.
Note that the step 4 may be fixed in the horizontal posture B, and a fixing member and a release member for fixing the step 4 may be provided at appropriate positions.

Speed control is performed by changing the output voltage to the traveling motor 23 by chopper control, and the vehicle body 13 is provided with speed control means for that purpose. This speed control means is specifically a speed control circuit including an arithmetic processing unit, and includes a switching means for switching speed control. The switching means includes a switching circuit in the speed control means and an external sensor.

The external sensor is a limit switch 6 provided at the root of step 4 in this example (see FIG. 2). At the root of the step 4, a cam 8 for pressing or releasing the limit switch 6 is provided in a state fixed with respect to the step 4, and rotates together with the rotation of the step 4 about the shaft 7 as a rotation axis. It is movable. When the step 4 is in the vertical position A, the limit switch 6 is not pressed by the cam 8. When the step 4 is in the horizontal position B, the limit switch 6 is set by the cam 8. When pressed, an ON signal is transmitted, and the electric signal is taken into the speed control means.

Referring to FIG. 4, the relationship between the position of step 4 and the ON / OFF of the limit switch 6 is shown in FIG. The limit switch 6 is turned on in the rotation range of the positions C and B, and the limit switch 6 is turned on unless the step 4 becomes close to the horizontal posture B.
Does not. This is based on the idea of switching to the boarding-type speed control only when the operator is in a state where the operator can get on in step 4, and is for ensuring reliable safety. Of course, the relationship between the position of step 4 and ON / OFF of the limit switch 6 can be arbitrarily changed.

FIG. 5 is a block diagram of the speed control means of the traveling motor 23 without a speed feedback system according to the present invention. Reference numeral 21 denotes an output voltage command value calculation unit that calculates an output voltage command value of the traveling motor 23 based on the accelerator angle detected by the accelerator angle detection sensor 20. Reference numeral 22 denotes a command to the traveling motor 23 based on the command value. This is a traveling motor drive unit that controls the output voltage by chopper control.

When there is no ON signal from the limit switch 6, the speed control means sets a speed control suitable for using the vehicle as a walking type, that is, a walking type speed control. Is set to speed control suitable for using the vehicle as a riding type, that is, riding type speed control.

The graphs in FIGS. 6 to 8 show both the case where the limit switch 6 is OFF, ie, the walking type speed control, and the case where the limit switch 6 is ON, ie, the riding type speed control. It shows the characteristics. FIG. 6 shows both characteristics in the relationship between the accelerator angle and the output voltage. FIG. 7 shows the relationship between the accelerator angle and the chopper duty ratio. FIG. 8 shows the relationship between the accelerator angle and the traveling speed of the vehicle.

More specifically, referring to FIG. 6, in both the walking type and the boarding type speed control, as the accelerator angle increases, the output voltage to the traveling motor 23 also increases proportionally. Even at the same accelerator angle, the output voltage differs between the walking type and the riding type, and the riding type is larger than the walking type. And
The maximum output voltage is set higher in the riding type than in the walking type. 7 and 8, when the chopper duty ratio is changed from d2 to d1, for example, when the chopper output voltage is reduced from 24V to 16V, the output voltage output to the traveling motor 23 is reduced, and the maximum speed is also reduced. It decreases from V2 (for example, 7 km / h) to V1 (for example, 4 to 5 km / h).

Looking at a specific example of the running speed, in the walking speed control, the running speed increases in proportion to the accelerator angle, and reaches 5 km / h, which is the maximum speed in the walking speed control at the maximum accelerator angle. Reach. This is the riding type speed control.
Similarly, the running speed increases in proportion to the accelerator angle, but the increase is larger than that of the walking speed control. At the maximum accelerator angle, the maximum speed of the riding speed control is 7 km / km.
h.

The accelerator can be rotated from the neutral position to both one side and the other side, and the relationship between the accelerator angle to one side and the output voltage and the relationship between the accelerator angle to the other side and the output voltage. Have the relationship seen in the graphs of FIGS. 6, 7, and 8, only the rotation direction of the traveling motor 23 is different. Of course, the present invention is not limited to this, and the relationship between the accelerator angle and the output voltage may be different between one side and the other side. In this embodiment, when the accelerator rotates to the one side,
It is assumed that the vehicle travels in a riding type in which the vehicle travels with the mounting table side in front, and when the vehicle turns to the other side, the vehicle travels in a walking type in which the vehicle travels with the vehicle body side facing forward.

In the above embodiment, an example was shown in which the output voltage of the riding type was always higher than the output voltage of the walking type even at the same accelerator angle (see FIG. 6). And the riding type may partially overlap (see FIG. 9).

The operation of the above configuration will be described. First,
When the cargo handling vehicle is used as a walking type, step 4 is used with the vertical posture A. Since the step 4 is in the vertical posture A, O
No N signal is transmitted, and thus the speed control by the speed control means is the walking speed control. The operator grasps the top portion of the operation handle 1 and walks while pulling the vehicle while operating the accelerator. The accelerator operation at this time is rotated so that the accelerator angle is on the other side from the neutral position. By the accelerator operation, the traveling motor 23 rotates in the other direction, whereby the steering drive wheel 3 rotates in the other direction E (see FIG. 1), and the vehicle travels in the other direction X.

In the above-mentioned walking type traveling control, the vehicle reaches only a speed of 5 km / h at the maximum, and always travels within the traveling speed corresponding to the walking speed of the operator. Thus, it is possible to eliminate the danger that the vehicle becomes faster than the walking speed due to an incorrect accelerator operation and the vehicle hits the operator.

Next, when the cargo handling vehicle is to be used as a riding type, step 4 is set to the horizontal posture B, and the operator boards this step 4. At step 4 in which the horizontal posture B has been reached, an ON signal is transmitted from the limit switch 6, and the speed control by the speed control means becomes the above-described riding type speed control. The operator grips the top portion of the operation handle 1 while riding on step 4 and drives the vehicle while operating the accelerator. The accelerator operation at this time is rotated so that the accelerator angle is one side from the neutral position. The above operation of the accelerator causes the traveling motor 23 to rotate in one direction.
Rotates in one side direction F (see FIG. 1), and the vehicle moves in one side direction Y.
Travel to.

In the above-mentioned riding type traveling control, the vehicle is at most 7
The vehicle travels at a speed of up to km / h, thereby realizing high-speed traveling as compared with a case where the vehicle is used as a walking type. As a result, the moving efficiency of the vehicle is improved and the efficiency of the cargo handling work can be improved as compared with the case of use in a walking type.

Next, a second embodiment will be described. This embodiment differs from the first embodiment only in the speed control means.
Only the different speed control means will be described below. Referring to FIG. 10, the above-described speed control means is a speed control means having no speed feedback system, whereas the present modified example is a speed control means having a speed feedback system.

More specifically, reference numeral 24 denotes a speed command value calculating means for calculating a speed command value based on the accelerator angle detected by the accelerator angle detection sensor 20, and 26 receives a signal from a speed sensor 28 attached to the traveling motor 23. Speed calculating means for calculating a vehicle speed value; 25, a speed deviation calculating means for obtaining a speed deviation between the speed command value and the vehicle speed value; and 27, an output voltage command value to the traveling motor 23 such that the speed deviation becomes zero. The output voltage command value calculating means 22 for determining the output voltage is determined by the chopper control based on the output voltage command value.

Next, a third embodiment will be described. This embodiment differs from the first and second embodiments only in the switching means, and only this switching means will be described below. The switching means has a human detector (not shown) for detecting the presence or absence of an operator in step 4. This human detector
A micro switch that is turned on / off according to the weight of a person, a contactless switch using a piezoelectric element whose output voltage changes according to the weight of the person, or a switch that operates by detecting the capacitance when a person gets on a vehicle, It is composed of a contact type or non-contact type sensor.

When the human detector does not detect an operator on step 4, the speed control means switches the speed control to a walking speed control (for example, 4 to 5 km / h). When step 4 is set to the horizontal posture B shown in FIG. 4 and the rider rides on step 4 and intends to use the cargo handling vehicle as a riding type, the human detector detects an operator and the speed control by the speed control means is performed by the riding type. Switch to speed control (for example, speed of 7 km / h). Therefore, the cargo handling vehicle can be driven at a high speed, and the efficiency of the cargo handling work is improved.

Next, a fourth embodiment will be described. The switching means of this embodiment has a manual switch. FIG.
Referring to FIG. 5, the changeover switch is a walking switch 30.
And a boarding switch 31 and correspond to the step limit switch 6 of FIG. For details, see FIG. 5 and FIG.
In the case of running as a walking type, the walking switch 30 is pressed, and a signal thereof is input to the output command value calculating means 21. Next, the detection value detected by the accelerator angle detection sensor 20 is input to the output voltage command value calculation means 21. As a result, the output command value calculating means 21 outputs a command value based on the calculation for the walking speed control to the traveling motor driving means 22. Then, the traveling motor driving means 22 to which the command value is input
Outputs an output voltage to the traveling motor. As a result, the traveling motor is rotated at a rotation speed based on the walking speed control, and the vehicle travels at a speed corresponding to the walking speed.

On the other hand, when the vehicle is traveling for boarding, the boarding switch 31 is depressed, and the signal is input to the output command value calculating means 21. Next, the detection value detected by the accelerator angle detection sensor 20 is input to the output voltage command value calculation means 21. As a result, the output command value calculation means 21 outputs a command value based on the calculation for the boarding type speed control to the traveling motor drive means 22.
Then, the traveling motor driving means 2 to which the command value is input
2 outputs an output voltage to the traveling motor. As a result, the traveling motor rotates at a rotation speed based on the riding type speed control and travels.

In the fourth embodiment, the walking switch 30
A lamp may be attached beside each switch so that it is possible to confirm which of the switch 31 and the boarding switch 31 is being pressed, or a sound may be emitted. In addition, each switch may be separated from one for walking and one for riding each time the switch is pressed, instead of being separated.

By attaching the changeover switch, the speed control can be switched irrespective of step 4. That is, in the above-described first to third embodiments, the switching of the speed control is performed automatically using the detection means to determine whether or not the operator is riding on the step. For example, if there is a request to use a walking type but run at a high speed, or to use a riding type but not to have a high speed, it cannot respond to these requests. Therefore, by allowing the operator to arbitrarily switch the speed control as in the present embodiment, it is possible to perform traveling in accordance with the preference of the operator or the traveling environment.

[0043]

As described above, the cargo handling vehicle of the present invention can be set to the optimal speed control as a walking type cargo handling vehicle when the operator does not board the step. Can be set to optimal speed control as a riding type cargo handling vehicle. This makes it possible to run at a relatively low speed when used as a walking type, and obtains the safety of the operator, and when used as a riding type, it can run at a higher speed than when using as a walking type, The efficiency of cargo handling can be improved.

[Brief description of the drawings]

FIG. 1 is a side view of a cargo handling vehicle according to a first embodiment of the present invention.

FIG. 2 is a plan view of a top portion of the operation handle according to the first embodiment of the present invention.

FIG. 3 is a diagram showing a step base of the cargo handling vehicle according to the first embodiment of the present invention.

FIG. 4 is an explanatory view of the operation of the steps of the cargo handling vehicle according to the first embodiment of the present invention.

FIG. 5 is a block diagram of a speed control device according to the first embodiment of the present invention.

FIG. 6 is a graph showing a relationship between an accelerator angle and an output voltage of the cargo handling vehicle according to the first embodiment of the present invention.

FIG. 7 is a graph showing a relationship between an accelerator angle and a chopper duty of the cargo handling vehicle according to the first embodiment of the present invention.

FIG. 8 is a graph showing a relationship between an accelerator angle and a vehicle speed of the cargo handling vehicle according to the first embodiment of the present invention.

FIG. 9 is a block diagram of a speed control device according to a modification of the first embodiment of the present invention.

FIG. 10 is a block diagram of a speed control device according to a second embodiment of the present invention.

FIG. 11 is a diagram showing switching means according to a fourth embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Operation handle 2 axis 3 Steering drive wheel 4 Step 5 Mounting table 6 Limit switch 7 Shaft 8 Cam 9 Spring 10 Stopper 11 Coil spring 12 Body body

Claims (3)

(57) [Claims] 1. A battery as a driving source, a driving wheel for rotation driven by electric power from the battery, speed control means for controlling a traveling speed by the driving wheel, and a load for loading a load. A loading and unloading vehicle having a table and a handle operated by an operator, wherein the handle is operated in the up and down direction to brake and release the drive wheels. Is provided so as to be pivotable so as to take a horizontal posture and a vertical posture with respect to the vehicle body and is urged to take a vertical posture by urging means, and the speed control means controls the traveling speed by the operation of the operator. An accelerator means for controlling the vehicle, and a switching means for switching the traveling speed controlled by the accelerator means to a plurality of speeds. Has a detector for detecting the turning of the step, and switches the speed control by the speed control means to a lower speed side when the step takes a vertical posture based on a detection result of the detector. Cargo handling vehicle. 2. The apparatus according to claim 1, wherein said switching means switches the speed control by said speed control means to a high speed side when said step turns from a vertical posture to a position close to a horizontal posture. Cargo handling vehicle as described. 3. The vehicle according to claim 1, wherein the cargo handling vehicle is a low-lift truck using the drive source as a battery.
Or a cargo handling vehicle according to any of 2.