JP2002316799A - Reach type forklift truck - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a reach type forklift truck with high safety capable of being surely operated, particularly, only when an operator stands on an operator stand at a specified position. SOLUTION: In this reach type forklift truck, a mast 2 and a fork 3 are installed at the front part of a body 1, and an operation panel 6, an operation stand 7 for an operator to operate the operation panel 6 in standing posture, and an access port 11 opened to gain access to the operation stand 7 are installed at the rear of the body 1. A pair of brake switches 12 and 13 disposed apart from the access port 11 of the operation stand 7, detecting each of both feet of the operator who gains access to the operation stand 7, and prohibiting the operation of the body 1 when not detecting are installed in this forklift truck.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reach type forklift focusing on the safety of an operator during a driving operation.

[0002]

2. Description of the Related Art As shown in the perspective view of FIG.
The reach type forklift is provided with a mast 102 that can move forward and backward at a front portion of a vehicle body 101, and a fork 103 that can move up and down along the mast 102. A driver's cab 105 for operating the operation panel 104 in a standing posture is provided, and further, for example, an entrance 106 opened backward is opened for an operator to get on and off the driver's cab 105.

[0003] A foot-operated brake switch 107 is provided on the cab 105 at a position away from the entrance 106 of the cab 105 so that the operator can operate the vehicle while standing at a predetermined position on the cab 105. , Cab 1
05 on the brake switch 10
For example, the driving operation of the operation panel 104 is enabled only when the player 7 is stepping on the left foot.

[0004]

In this conventional reach-type forklift, the operator steps on the brake switch 107 on the cab 105 to ensure that the operator stands at the correct position on the cab 105. However, if the brake switch 107 is depressed with one foot, the operator on the cab 105 can perform a driving operation.

[0005] However, in this conventional reach-type forklift, even if the operator stands on the correct position of the cab 105 and steps on the brake switch 107 with one foot, the operator unconsciously touches the foot on which the brake switch 107 is not pressed. It has been noticed that there is a possibility that the vehicle body 101 may be operated to run out of the entrance 106.

If the operator retreats the vehicle body 101 in a state where one foot protrudes behind the cab 105 and hangs down, turns on the spot, or turns while retreating, the vehicle protrudes from the cab 105. The foot may come into contact with other things around or be caught between the cab 105 and other things around.

In order to solve this problem, the entrance 106 is extended to a position lower than the cab 105, and the portion of the cab 105 facing the entrance 106 is recessed inside the vehicle body 1 so as to operate the vehicle. There is a method in which the operator's foot protruding from the platform 105 is located in a position that can be protected by the vehicle body 101 in the entrance 106, but this method makes the cab 105 narrow and cramped, and furthermore, the rear portion of the vehicle body 1 There are problems such as complicated shapes and significant cost increases.

SUMMARY OF THE INVENTION An object of the present invention is to solve the problems of the prior art and to provide a highly safe reach-type forklift that prevents an operator from protruding both feet from a cab during driving operation of a vehicle body. Is what you do.

[0009]

In order to achieve this object, a reach type forklift according to the present invention is arranged at a position distant from the entrance of the above-mentioned cab, and separates both feet of an operator who gets on the cab. A technical means is adopted in which a pair of brake switches for detecting and detecting the non-detection and prohibiting the operation of the vehicle body are provided.

[0010] According to this, since the brake switch is arranged at a position away from the entrance, the foot which depresses the brake switch is placed at a position not protruding from the cab. If the operator's feet on the driver's cab are not located at the position where the brake switch that does not protrude from the driver's cab is depressed, the operator cannot operate the vehicle body. Can be obtained at a position not protruding from the cab.

In the present invention, the brake switch
It is not particularly limited as long as it is a foot-operated type.For example, a foot switch operated by a tread plate installed in a plane on the floor of the cab or a plane installed on the floor of the cab is used. A pressure-sensitive mat switch may be used, or an organ-operated or suspended pedal-type pedal provided on the driver's cab so as to be able to move up and down may be used.

As a method of prohibiting the operation of the vehicle body when either one of the brake switches is not operated,
For example, a method of stopping the supply of electric power for driving the control panel, a method of stopping the supply of electric power to a control circuit portion for controlling the operation of the vehicle body, and a supply of electric power for driving a driving device provided for the operation of the vehicle. A method of stopping the power supply and the like can be cited. In order to stop the supply of the power, there are a method of directly interposing a brake switch in a circuit for supplying the power and a method of using a relay switch.

It is preferable that both brake switches are disposed with a gap larger than at least the width of one foot in order to prevent simultaneous operation with one foot.

Further, in order to enhance operability, it is preferable to set the interval between the two brake switches to an interval between both feet which is naturally widened when the operator stands, for example, an interval equivalent to the shoulder width.

In order to achieve the above object, another reach-type forklift according to the present invention individually detects both feet of an operator riding on a cab arranged at a position distant from the entrance of the cab. It is characterized by comprising a pair of foot-operated brake switches, and alarm means for issuing an alarm when the driving operation panel is operated in a state where one or both of the pair of switches are not operated. Adopt technical means.

According to this, if the operator does not step on one or both brake switches, that is, if the operator's feet are protruding from the cab or are likely to protrude, an alarm is issued. ,
The effect is obtained that prompts the operator to correct the position of the foot.

The structure of the brake switch in the reach type forklift according to the present invention, its electrical or electronic connection, and the arrangement on the cab are the same as those of the reach type forklift according to the present invention described above. It may be configured as follows.

The alarm means of the present invention may be configured so as to issue an alarm to the operator. For example, a warning sound such as a bell sound, a buzzer sound, a chime sound, or an auditory sound such as a sound alarm is provided. Audible alarm means to generate an appealing alarm, turning on the warning light, blinking the warning light, turning the warning light, displaying warning texts and warning drawings, lighting or emitting light on the display surface displaying warning texts and warning drawings, etc. It is possible to use a visual alarm that issues an alarm that appeals to the sight, a tactile alarm that appeals to the operator's tactile sensation such as vibration, coldness, and warmth. Of course, in the present invention, a plurality of types of alarm means having different types of alarms such as an audible alarm means, a visual alarm means, and a tactile alarm means may be used in combination. Further, the present invention described above may be replaced with another present invention described later, or the present invention described above and another present invention described later may be both used.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A reach type forklift according to one embodiment of the present invention will be specifically described with reference to the drawings.
It is as follows.

FIG. 1 is a perspective view schematically showing a reach-type forklift according to an embodiment of the present invention as viewed from the left rear side. As shown in FIG. The vehicle includes a mast 2 that can move forward and backward and expand and contract in the vertical direction, and a fork 3 supported by the mast 2 so as to be able to move up and down along the mast 2 and to be able to undulate.

The mast 2 is extended and retracted by a lift cylinder 4 and advanced and retracted by an advance / retreat cylinder. The fork 3 is moved up and down by the lift cylinder 4 in conjunction with the extension and retraction of the mast 2, and is raised and lowered by a tilt cylinder. I try to make it.

At the rear of the vehicle body 1, there is provided a casing 5 for accommodating a traveling device, a control circuit and a battery as a power supply, and an operation control panel 6 is disposed on the upper surface of the casing 5.

The operation panel 6 includes a lift control lever 6a for controlling the lift cylinder 4, a tilt control lever 6b for controlling the tilt cylinder, an advance / retreat control lever 6c for controlling the advance / retreat cylinder, and a stop of the vehicle body 1. In addition to a traveling control lever 6d for controlling the traveling speed including the traveling speed and the traveling direction (forward, backward) of the vehicle body 1, a control panel 6e,
A headlight switch, a main switch, an emergency stop switch, and the like are arranged, and the control panel 6e incorporates an accelerator key, a speed switch key, an output switch key, a charge amount display unit, various alarm lamps, a speed display panel, and the like. I have.

Further, a driver's cab 7 is provided at the rear of the vehicle body 1 behind the driver's operation panel 6 for the operator to operate the operation panel 6 in a standing posture. The casing 5 extended to the left of 7
A steering wheel 8 is arranged above the portion of the vehicle body 1. By operating the steering wheel 8, a steering wheel 9 provided as a driving wheel provided at a rear left portion of the vehicle body 1 is turned.

At the right front, left front, and right rear of the vehicle body 1, supporting wheels 10 for supporting loads are rotatably supported around left and right axes.

In the rear part of the vehicle body 1, there is provided an entrance 11 which is open to the operator's cab 5 from behind the operator's body 1 for the operator to get on and off. A pair of left and right brake switches 12 and 13 operated by a stepped-on operator is provided.

Here, the pair of brake switches 1
It is necessary that the steps 2 and 13 be arranged at positions farther from the entrance 11 so that their feet do not protrude from the cab 7.

FIG. 2 is a plan view of the cab 7, and FIG.
FIG. 4 is a rear view of the cab 7, FIG. 4 is a right side view of the cab, and as shown in FIGS. 2 and 3, the left brake switch 12 is an organ pedal type, that is, one end ( The front end (here, the front end) has a pedal 12a rotatably connected to the casing 5 in front of the cab 7, and a switch main body 12b formed of, for example, a limit switch operated by the pedal 12a. The switch body 12b is turned on, and the pedal 12a
When the foot is released, the pedal 12a is raised by the urging means, and the switch body 12b is automatically turned off.

As shown in FIGS. 3 and 4, the brake switch 13 on the right side includes a switch body composed of a pressure-sensitive mat switch placed on the floor plate 14 of the driver's cab 7 so as to be planar. The upper side and four lateral sides of the switch body are covered, and the floor plate 1 of the driver's cab 7 is sandwiched by the switch body.
4 and a tread plate 13a which is placed in a plane on the
When the step board 13a is stepped on, the switch body is turned on, and when the foot is released from the step board 13a, the switch body is turned off.

These brake switches 12, 13 are
Although not particularly limited, the interval larger than the width of the work shoes worn by the operator, for example, about twice the width of the shoes, ie, 20c
By arranging the brake switches at intervals of about m, the operator is prevented from unconsciously stepping on the brake switches 12, 13 with one foot at the same time.

The brake switches 12, 13
The distance (center-to-center distance) is about the shoulder width, that is, 30 cm to 50 cm, so that the operator can operate the vehicle in a comfortable posture.
It is set to the degree.

FIG. 5 is a control system diagram of the forklift.

The control circuit body 15 shown in FIG. 5 is arranged in the case 5 and connected to a DC power supply 17 composed of a battery via a power supply circuit 16.

The control circuit body 15 includes a valve control unit, a traveling control unit 152, a turning control unit 153, an auxiliary control unit 154, a voltage divider 15
5 is provided.

The valve control unit controls an electromagnetic valve array for controlling the supply and discharge of pressure oil to the lift cylinder 4, the forward / backward cylinder, and the tilt cylinder. The travel control unit 152 drives the steered wheels 9 to travel. The traveling driving means 21 is controlled. Further, the steering control unit 153
Controls the turning drive unit 22 that drives the steering wheel 9 to turn, and the auxiliary control unit 154 controls various accessories such as the headlight 23.

The hydraulic unit that supplies pressure oil to the lift cylinder, the forward / backward cylinder, and the tilt cylinder via the above-described valve array has a built-in means for controlling the operation thereof, and is provided via a main switch 25 interposed in the power supply circuit 16. Directly connected to the DC power supply 17 in series.

In addition, the above-mentioned valve array, traveling drive means 2
1. Accessories such as the turning drive means 22 and the headlight 23 are also connected to the DC power supply 17 via the main switch 25, and are supplied with electric power from the DC power supply 17 based on a control signal given from a corresponding control unit. It works.

The valve control unit, the traveling control unit 152, the turning control unit 153, and the auxiliary control unit 154 are connected to the DC power supply 17 via the voltage divider 155 and the main switch 25 in series.
5 is activated with a DC voltage lower than the voltage of the DC power supply 17 supplied from the DC power supply 5.

By the way, a control unit drive wiring 156 for connecting the traveling control unit 152 to the voltage divider 155 and a control unit drive wiring 157 for connecting the turning control unit 153 to the voltage divider 115 are respectively connected to the relay switch r.
relay coils Ry1 and Ry for driving these relay switches ry1 and ry2.
2 is connected to the DC power supply 17 in series with the pair of brake switches 12, 13 and the voltage divider 155.

The control circuit body 15 includes the control panel 6e, sensors for control, for example, steering wheel turning angle detecting means for detecting the turning angle of the steering wheel 8, and the turning angle of the steering wheel 9. Steering wheel turning angle detecting means, body 1
Traveling speed sensor for detecting the traveling speed of the fork 3, forward / backward sensor for detecting the forward / backward position and forward / backward speed of the fork 3,
Sensors such as an up / down sensor for detecting the up / down angle and the up / down speed of the fork 3, an up / down sensor for detecting the up / down position and up / down speed of the fork 3, and an emergency stop switch 33 are connected, but these sensors are not directly related to the present invention. Therefore, the detailed description is omitted.

As described above, the relay coil Ry1 for driving the relay switch ry1 is connected in series with the brake switches 12, 13, so that the operator steps on both brake switches 12, 13 to turn on the brake switch. If not, the travel control unit 152 is deactivated, the control of the travel drive means 21 is stopped, and the vehicle 1 cannot travel. Similarly, the relay coil Ry2 for driving the relay switch ry2 is connected in series with the brake switches 12, 13, so that the operator steps on both brake switches 12, 13 at a position away from the entrance 11. If not, turn control unit 1
52 is deactivated, the control of the turning drive means 22 is stopped, and the steered wheels 9 cannot be turned.

That is, unless the operator steps on both brake switches 12 and 13 individually with both feet, the driving operation of the vehicle body 1 becomes impossible, and the operator steps on both brake switches 12 and 13 and both feet If the feet are moved so as not to protrude from the stand 7, the vehicle body 1 can be made to retreat, turn on the spot, or turn while retreating.

In this way, if the operator's feet are surely positioned so as not to protrude from the cab 7 during the driving operation of the vehicle body 1, the operator can unknowingly operate the cab 7 during the driving operation. Since it is prevented from dropping the foot outside, other things around may contact the foot dropped unintentionally outside the cab 7 or the foot may be caught between the cab 7 and other things around. Thus, there is no possibility that the reach-type forklift will be safe.

FIG. 6 is a plan view of a cab 7 of a reach type forklift according to another embodiment of the present invention, FIG. 7 is a rear view of the cab 7, and FIG. As shown in FIGS. 6 to 8, the brake switch 13 on the right side has a front end rotatably connected to the case 5, and the rear end thereof can be flipped higher than horizontal when opened. It has a pedal-type pedal 13b and a switch body 13c which is operated by the pedal 13b and is, for example, a limit switch.

When the pedal 13b is depressed, the switch body 13c is turned on. When the switch 13b is released, the pedal 13b is jumped higher than horizontal by the urging means, and the switch body 13c is automatically turned off.

The switch body 13c is directly operated by the pedal 13b. However, the switch body 13c is disposed under the floor of the cab 7 or in the case 5, and the switch body 13c is connected to the switch body 13c. A transmission means such as a link or a release wire may be interposed therebetween, and the switch body 13c may be operated by the pedal 13c via the transmission means. The same applies to the left brake switch 12.

The other constructions, operations and effects of this embodiment are the same as those of the previous example, so that detailed description thereof will be omitted to avoid duplication.

FIG. 9 is a control system diagram of a reach type forklift according to another embodiment of the present invention. In this embodiment, an alarm circuit 26 externally provided to the control circuit body 15 and an alarm control Unit 27, traveling operation detecting means 28 for detecting operation of the traveling control lever 6d, and steering operation detecting means 2 for detecting operation of the steering wheel 8
9 are provided.

The traveling operation detecting means 28 is activated by the direct current supplied from the voltage divider 155 of the control circuit body 15, continuously detects the position of the traveling control lever 6d, differentiates the detected value, When the absolute value of the differentiation result is not zero, a detection signal consisting of an ON signal (high value signal) is output,
When the differential result is zero, a non-detection signal consisting of an off signal (low value signal) is output.

The steering operation detecting means 29 is also activated by the direct current supplied from the voltage divider 155, continuously detects the turning angle of the steering handle 8 and differentiates the detected value. When the absolute value of the differentiation result is not zero, a detection signal consisting of an ON signal (high value signal) is output, and when the differentiation result is zero, a non-detection signal consisting of an OFF signal (low value signal) is output.

The alarm control unit 27 is connected to the voltage divider 155 of the control circuit body 15 via the control unit drive wiring 30 with the relay switch ry3 interposed therebetween, and activated by the DC supplied from the voltage divider 155. The detection signal of the traveling operation detecting means 28 and the steering operation detecting means 2
When one or both of the detection signals 9 are input, the alarm means 26 is activated.

The relay coil Ry3 for driving the relay switch ry3 is connected to the pair of brake switches 12,
13, both brake switches 12, 13
Are turned on, and when the relay coil Ry3 is energized, the relay switch ry3 is turned off. One or both of the brake switches 12, 13 are turned off. When the relay coil Ry3 is de-energized, the relay coil ry3 is turned off. Is turned on, and the alarm control unit 27 is activated.

The alarm means 26 preferably emits an alarm which can be easily recognized by an operator and can be easily recognized by others around the same. For example, a lamp such as a red rotating light, a yellow rotating light, etc. By using a flashing light such as a strobe flash lamp to give a visual stimulus to the operator or others around him, or to give an auditory stimulus to the operator or others around him by buzzer sound, bell sound, chime or voice, The travel operation lever 6d and the steering handle 8 may be vibrated to give a tactile stimulus to the operator.

In the state where the main switch 25 is turned on, the operator does not step on one or both of the brake switches 12 and 13 and, for example, drives the travel control lever 6d.
Is operated, a detection signal is input from the traveling operation detecting means 28 to the alarm control unit 27 in the active state, and the alarm means 2 is
6 is activated. This warning is continued until the operator corrects the foot position and turns on both brake switches 12 and 13 or stops driving.

When the alarm is given, the normal operator does not continue the driving operation with the alarm being given, but gives up the driving operation or changes the position of the foot while continuing the driving operation. Correction stops the alarm or interrupts the driving operation, corrects the position of the foot, stops the alarm, and restarts the driving operation.

That is, if the operator performs a driving operation in a state where the operator's feet are protruding from the cab 7 or may be protruding, an alarm is issued and the operator can perform the driving operation by correcting the position of the feet. In response to this warning, the operator does not move the foot out of the cab 7 in response to the alarm, that is, the two brake switches 12, 1
By adjusting the positions of the pedals 3 individually to the stepping positions, it is possible to prevent the feet from hanging down on the cab 7 during the driving operation.

The same applies when the steering control lever 6d is operated.

In particular, in this embodiment, as in the previous example, the traveling drive means 21 and the turning drive means 22 do not operate unless the operator puts both brake switches 12, 13 at the positions where the two feet are individually depressed. The body 1
The warning is issued in a state where there is no concern that the vehicle starts moving, and it is possible to more reliably prevent the operator from operating the vehicle by hanging his / her feet behind the cab 7 from the entrance / exit 11.

The other constructions, operations and functions of this embodiment are the same as those of the previous two examples, so that detailed description thereof will be omitted to avoid duplication.

[0060]

As described above, the reach type forklift of the present invention is arranged at a position distant from the entrance of the above-mentioned cab, detects both feet of the operator who gets on the cab individually, According to this, a pair of brake switches for inhibiting the operation of the vehicle body are provided, so that the operator steps on both brake switches individually with both feet, and the operator's both feet do not protrude from the cab. If it is not located, the operation of prohibiting the operation of the vehicle body can be obtained.

Accordingly, there is no danger that the vehicle body will be driven with the operator's feet protruding from the cab, and such driving may cause the feet to come into contact with other objects in the surroundings or to be pinched between the surrounding objects and the vehicle body. This makes it possible to obtain a highly safe reach-type forklift that is not likely to be dropped.

Further, another reach-type forklift according to the present invention is disposed at a position distant from the entrance of the above-mentioned cab, and a pair of brake switches for individually detecting both feet of the operator on the cab, According to this, it is provided with alarm means for issuing an alarm when an operator on the cab operates a driving operation panel while one or both of the pair of switches are not operated.
The operator steps on both brake switches individually with both feet,
When the operator operates the operation panel without both feet of the operator protruding from the cab, an alarm is issued.

Therefore, according to another reach-type forklift according to the present invention, the two brake switches, which do not stop the driving operation of the vehicle body and do not protrude from the cab, are set to the positions where the two feet are individually depressed. The operator is encouraged to take safety actions such as running out of the vehicle, and the operator takes these safety actions in response to the warning, so that there is no danger of the vehicle being driven with the operator's feet protruding from the cab. A highly safe reach-type forklift can be obtained in which there is no danger of the feet contacting the surrounding objects or being caught between the surrounding other objects and the vehicle body due to appropriate driving.

[Brief description of the drawings]

FIG. 1 is a perspective view of the present invention.

FIG. 2 is a plan view of the present invention.

FIG. 3 is a rear view of the present invention.

FIG. 4 is a right side view of the present invention.

FIG. 5 is a circuit block diagram of the present invention.

FIG. 6 is a plan view of the present invention.

FIG. 7 is a rear view of the present invention.

FIG. 8 is a right side view of the present invention.

FIG. 9 is a circuit block diagram of the present invention.

FIG. 10 is a perspective view of a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Body 2 Mast 3 Fork 6 Driving operation panel 7 Driving cab 11 Getting on and off 12 Brake switch 12a Pedal 13 Brake switch 13a Tread plate 13b Pedal

Claims (11)

[Claims] 1. A mast movable forward and backward at a front portion of a vehicle body,
A fork that can be raised and lowered along the mast is provided, and a driving operation panel and a driver's cab for operating the operation panel in an upright posture are provided at the rear of the vehicle body, and are opened for getting on and off the driver's cab. A reach-type forklift provided with a lift entrance and exit, which is disposed at a position distant from the entrance of the above-mentioned cab, individually detects both feet of the operator who gets on the cab, and prohibits the operation of the vehicle body when it is not detected A reach-type forklift comprising a pair of brake switches. 2. The reach-type forklift according to claim 1, wherein one or both of the pair of brake switches comprises a foot switch operated by a tread plate installed on a floor surface of the cab. 3. The reach-type forklift according to claim 1, wherein one or both of the pair of brake switches includes a pressure-sensitive mat switch that is installed in a plane on the floor of the cab. 4. The system according to claim 1, wherein one or both of the pair of brake switches are operated by an organ pedal type or a suspension pedal type pedal supported on the floor of the driver's cab so as to be able to move up and down. Reach type forklift. 5. A mast movable forward and backward at a front portion of a vehicle body,
A fork that can be raised and lowered along the mast is provided, and a driving operation panel and a driver's cab for operating the operation panel in an upright posture are provided at the rear of the vehicle body, and are opened for getting on and off the driver's cab. And a pair of brake switches, which are arranged at a position distant from the cab of the cab and individually detect both feet of an operator boarding the cab, and a pair of the above-mentioned pair of brake switches. Alarm means for issuing an alarm when an operator on the driver's cab operates the operation console while one or both of the switches are not operated. 6. The reach-type forklift according to claim 5, wherein one or both of the pair of brake switches comprises a foot switch operated by a tread plate installed on a floor surface of the cab. 7. The reach-type forklift according to claim 5, wherein one or both of the pair of brake switches comprises a pressure-sensitive mat switch that is provided in a plane on the floor of the driver's cab. 8. The system according to claim 5, wherein one or both of the pair of brake switches are operated by an organ pedal type or a suspension pedal type pedal supported on the floor of the driver's cab so as to be able to undulate. Reach type forklift. 9. The reach-type forklift according to claim 5, wherein the alarm means comprises an auditory alarm means that appeals to the hearing of the operator. 10. The reach type forklift according to claim 5, wherein said alarm means comprises a visual alarm means for issuing an alarm appealing to the visual sense of an operator. 11. The reach-type forklift according to claim 5, wherein the warning means comprises a tactile warning means that appeals to a tactile sensation of an operator.