JPH1149497A - Fork inclination notification device for forklift - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fork inclination notification device of a forklift which is capable of notifying a driver of inclination of a fork without lowering efficiency of a load work and narrowing a work visual field. SOLUTION: When a driver operates a tilt lever and tilts a mast, an electric resistance value between terminals A and B of an inclination detecting part 12 mounted on the outside face of the mast changes. When the driver turns on a switch 13 provided at the upper end of the tilt lever at this stage, current corresponding to the electric resistance value between the terminals A and B flows from a battery 11. A sound waveform of a frequency according to this current is formed by a waveform forming part 14 and sound is produced from a speaker 15. The driver recognizes inclination of a fork tilting together with the mast based on the frequency of sound produced from the speaker 15.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for informing a forklift of a forklift, and more particularly to an apparatus for informing a driver of a fork inclination by voice during a cargo handling operation.

[0002]

2. Description of the Related Art In a cargo handling operation using a forklift, it is necessary to level a fork when, for example, inserting and removing a fork from a hole of a pallet. Especially when the fork is located at a height different from the driver's viewpoint, it is difficult to position the fork.

Therefore, as shown in FIG. 11, an angle indicator 4 is provided on the rear surface of the mast 2 which is tilted in the front-rear direction by the tilt cylinder 1, that is, on the surface facing the driver's seat 3, and the inclination angle of the mast 2 is determined. A forklift designed to display on the angle display 4 has been developed. Fork 5
Is provided so as to be able to move up and down along the mast 2, and the inclination of the fork 5 is changed by tilting the mast 2.

[0004] As shown in FIG.
Has an L-shaped link 8 rotatably provided around a fixed shaft 7 in a case 6, and a weight 9 attached to one end of the link 8, and has a link oriented substantially horizontally. The other end of 8 is used as a pointer 10. As shown in FIG. 13, an opening 11 is formed on the front side of the case 6 facing the driver's seat 3, or this opening is formed of a transparent plate so that the hands 10 inside the case 6 can be seen from the driver's seat 3. A scale 12 indicating the neutral position (vertical position) of the mast 2 is formed at the center of the front of the case in the vertical direction.

[0005] The operation of the mast 2
Is tilted, the case 6 is also tilted.
Always hangs vertically downward, the link 8 rotates relative to the case 6, and as a result, the pointer 10
2 in the vertical direction. By directly viewing the relative position of the pointer 10 with respect to the scale 12 from the driver's seat 3, the inclination angle of the mast 2, that is, the inclination of the fork 5 can be grasped.

[0006]

However, when trying to grasp the inclination of the fork 5 during the cargo handling operation, the driver takes his / her eyes away from the load or fork 5 to be worked and displays the angle attached to the mast 2. There is a problem that the operator has to look at the pointer 10 of the container 4 and the work efficiency is reduced. In addition, since the angle display 4 needs to be mounted at a position that is easy for the driver in the driver's seat 3 to see, the work angle of the angle display 4 may reduce the working field of view and the degree of freedom in the layout of other functional parts may be reduced. There is. The present invention has been made to solve such a problem, and a forklift forklift can notify a driver of a fork inclination without reducing the efficiency of cargo handling work or narrowing a work field of view. It is an object to provide a notification device.

[0007]

According to the present invention, there is provided a fork lift informing device for a forklift, comprising: a tilt detecting section which indicates a different electric resistance value according to the tilt of the fork; The apparatus includes a waveform forming unit that forms a sound waveform, and a sound generating unit that generates sound toward a forklift driver based on the sound waveform formed by the waveform forming unit. As the inclination detecting unit, a movable contact of a variable resistor formed at one end of an arm that is swingably provided and a weight attached to the other end of the arm can be used.

According to another aspect of the present invention, there is provided a fork lift informing device for a forklift having a plurality of contact points and selecting one of the plurality of contact points in accordance with the fork inclination. A plurality of waveform forming sections connected to the plurality of contacts and forming audio waveforms having different contents indicating the inclination of the fork, and a waveform forming section connected to the contact selected by the inclination detecting section. And a sound generating unit that generates sound toward the driver of the forklift based on the sound waveform. As the tilt detector, a movable contact that selectively contacts one of a plurality of contacts at one end of an arm that is swingably provided, and a weight attached to the other end of the arm may be used. it can.

The tilt detecting section can be attached to a mast of a forklift provided to be tiltable.
Further, a transmission unit and a reception unit that perform wireless transmission may be further provided, and a wireless connection may be provided between the tilt detection unit and the sound generation unit.

[0010]

Embodiments of the present invention will be described below with reference to the accompanying drawings. Embodiment 1 FIG. FIG. 1 shows the configuration of a fork tilt notification device of a forklift according to Embodiment 1 of the present invention. A tilt detection unit 12, a switch 13, and a waveform forming unit 14 are connected in series between both ends of the battery 11, and a speaker 15 serving as a sound generating unit is connected to the waveform forming unit 14.

As shown in FIG. 2, the inclination detecting unit 12 includes a contact 17 mounted on an upper part in a case 16 and
Each of the right and left sides of the contact 17 has an electric resistor 18 attached in an arc shape, and a terminal A is drawn from the contact 17. A fixed shaft 19 is provided below the contact 17, and an arm 20 made of a conductor is attached to the fixed shaft 19 so as to be swingable. The arm 20 is formed to be thin so as to have elasticity, and the upper end of the arm 20 is always used as a contact 17 or an electric resistor 18 by utilizing the elasticity.
It is configured to be able to slide while maintaining the state of contact with the device. Another terminal B is drawn out from the arm 20 near the fixed shaft 19. The arm 20 has a weight 21 at its lower end for constantly holding the arm 20 in the vertical direction.
And a damper 22 for preventing excessive vibration of the arm 20 is connected.

Since the position of the upper end of the arm contacting the contact 17 or the electric resistor 18 changes according to the swing of the arm 20, the contact 17, the electric resistor 18 and the arm 20 are changed.
Thus, a variable resistor as shown in FIG. 3 is formed between the terminals A and B.

As shown in FIG. 4, such an inclination detecting unit 12 is attached to an outer surface of a mast 23 provided upright at a front part of a forklift. The mast 23 supports the fork 24 so as to be able to move up and down, and the tilt cylinder 25
Can be tilted back and forth by the action of
The tilt of the fork 24 changes with the tilt of the arm 20. When the fork 24 is horizontal,
The case 16 is attached to the outer surface of the mast 23 by adjusting the direction of the case 16 in advance so that the upper end of the case 16 contacts the contact 17.

A driver's seat 26 is disposed at the center of the forklift, and a steering wheel 2 is provided in front of the driver's seat 26.
7, a tilt lever 28, and a traveling lever (not shown)
A cargo handling lever and the like are provided. Further, a head guard 29 is provided above the driver's seat 26, and a speaker 15 is provided on the lower surface of the head guard 29 toward the driver's seat 26.
Is attached.

As shown in FIG. 5, a push button type switch 13 is provided at the upper end of the tilt lever 28. The battery 11 and the waveform forming unit 14 shown in FIG. 1 are mounted on the outer surface of the mast 23 together with the inclination detecting unit 12 or the head guard 2 together with the speaker 15.
9 or may be attached to the lower part of the instrument panel on which the tilt lever 28 and the like are provided.

Next, the operation of the fork tilt notification device according to the first embodiment will be described. When the driver in the driver's seat 26 operates the tilt lever 28, the plunger of the tilt cylinder 25 expands and contracts, and the mast 23 tilts in the front-rear direction of the vehicle. Along with this, the case 16 of the tilt detection unit 12 mounted on the outer surface of the mast 23 also tilts, but the arm 20 swingably attached to the case 16 via the fixed shaft 19 causes the gravity acting on the weight 21 to act on the weight 21. Therefore, the arm 20 swings relatively to the case 16 as shown by a dashed line in FIG. As a result, the upper end of the arm 20 is moved from the contact 17 to the electric resistor 18.
Moving upward, the value of the electric resistance between the terminals A and B changes.

Here, when the driver presses the switch 13 provided at the upper end of the tilt lever 28 to turn it on, a current corresponding to the electric resistance value between the terminals A and B flows from the battery 11, and according to this current, A sound waveform having the frequency is formed by the waveform forming unit 14, and sound is emitted from the speaker 15. The driver listens to the sound flowing from the overhead speaker 15 without taking his eyes off the load or the fork 24 to be worked, and grasps the inclination of the fork 24 that tilts with the mast 23 by the frequency, that is, the pitch. can do. Even if the mast 23 is tilted forward or backward from the vertical state, the pitch of the sound emitted from the speaker 15 similarly changes. When the user releases the switch 13 and turns it off, the sound generation from the speaker 15 is stopped.

As described above, since the driver does not need to look directly into the inclination detecting section 12, the degree of freedom in mounting the mast 23 at a large position is great, and the work field of view and the layout for mounting other functional parts are obstructed. No, easily mast 2
3 can be attached. Further, although a push button type switch is used as the switch 13, a snap type or slide type switch may be used.

As shown in FIG. 6, a headphone 30 can be connected to the waveform forming section 14 instead of the speaker 15 as a sound generating section. The driver can reliably grasp the inclination of the fork 25 by voice even in a work environment where there is noise or the like by working with the headphones 30 attached to the head.

Embodiment 2 FIG. 7 shows a configuration of a fork tilt notification device according to the second embodiment. This device has two circuits, a transmission side and a reception side. In the transmission side circuit, a tilt detection unit 12, a switch 31, and a transmission unit 32 are connected in series between both ends of a battery 11. on the other hand,
In the receiving circuit, the switch 1 is connected between both ends of the battery 33.
3, the receiving unit 34 and the waveform forming unit 14 are connected in series,
A speaker 15 is connected to the waveform forming section 14. The battery 11, the inclination detecting unit 12, the switch 13, the waveform forming unit 14, and the speaker 15 are the same as those used in the device of the first embodiment shown in FIG.

The transmitting circuit is mounted on the mast of the forklift, and the receiving circuit is mounted on the machine side of the forklift. When the switch 31 of the transmitting side circuit is turned on during the cargo handling operation, a current having a magnitude corresponding to the electric resistance value between the terminals A and B of the inclination detecting unit 12 flows through the transmitting unit 32, and the transmitting unit 32 The size is wirelessly transmitted to the receiving unit 34 of the receiving side circuit using radio waves, infrared rays, or the like. In the receiving side circuit, the driver can switch 1
3 is turned on, whereby the signal transmitted from the transmitting unit 32 is received by the receiving unit 34. With this receiving unit 34,
A current proportional to the magnitude of the current flowing to the transmitting unit 32 flows to the waveform forming unit 14, an audio waveform having a frequency corresponding to the current is formed, and a sound is emitted from the speaker 15.

By performing wireless transmission between the transmitting unit 32 and the receiving unit 34 in this manner, wiring between the mast and the machine is not required, and the degree of freedom in arranging various devices is increased. As a result, a layout that takes into account work efficiency can be realized.

Embodiment 3 FIG. FIG. 8 shows a configuration of a fork tilt notification device according to the third embodiment. The tilt detecting unit 35 is connected to the battery 11 via the switch 13, and two waveform forming units 36 and 37 are connected to the tilt detecting unit 35 in parallel. The waveform forming units 36 and 37 form audio waveforms having contents of “neutral” and “inclined”, respectively.
Are connected to a common speaker 15.

The inclination detecting section 35 has a contact 42 mounted on the upper part in the case 41, and contacts 43 and 44 disposed on both right and left sides of the contact 42, respectively. A fixed shaft 45 is provided below the central contact 42, and the fixed shaft 4
An arm 46 made of a conductive material is attached so as to be swingable around 5. The arm 46 is formed to be thin so as to have elasticity, and the upper end of the arm 46 can be slid while always maintaining the contact state with the contacts 42 to 44 by using the elasticity. At the lower end of the arm 46, a weight 47 for constantly holding the arm 46 in the vertical direction is attached. The waveform forming section 36 is connected to the contact 42, the waveform forming section 37 is connected to the contacts 43 and 44, and one end of the switch 13 is connected to the arm 46 near the fixed shaft 45.

As in the first embodiment, the tilt detecting section 35 is attached to a mast of a forklift,
Reference numeral 5 is attached to the head guard so that it faces downward. When the mast is oriented vertically and the fork is horizontal, the upper end of the arm 46 is in contact with the contact 42, and when the driver presses the switch 13 provided at the upper end of the tilt lever to turn it on, the battery 11 to arm 46
In addition, a current flows through the waveform forming unit 36 via the contact 42 and the speaker 15 emits a sound “neutral” in accordance with the sound waveform formed by the waveform forming unit 36. Also,
When the tilt detection unit 35 tilts with the mast, the arm 46
Swings relatively to the case 41 as shown by a chain line. As a result, when the upper end of the arm 46 comes into contact with the contact point 43 or 44 and the switch 13 is pressed, a current flows from the battery 11 to the waveform forming section 37, and the speaker follows the audio waveform formed by the waveform forming section 37. Fifteen
Sounds "tilting". For this reason, the driver can more reliably and easily grasp the inclination of the fork.

In the fork inclination notifying apparatus shown in FIG. 8, the waveform forming section 37 is commonly connected to the contacts 43 and 44 of the inclination detecting section 35. However, as shown in FIG. The different waveform forming units 38 and 39 may be connected to each other, and the speaker 15 may be commonly connected to the three waveform forming units 36, 38 and 39. The waveform forming sections 38 and 39 form audio waveforms having the contents of “tilting backward” and “tilting forward”, respectively.
When the mast is located in the vertical direction, the upper end of the arm 46 comes into contact with the contact point 42 and a sound "neutral" is emitted from the speaker 15 by the waveform forming portion 36, and the mast is tilted backward and the upper end of the arm 46 is tilted. When the contact comes in contact with the contact 43, the waveform forming unit 38 emits a sound of “tilting backward”, and when the mast leans forward and the upper end of the arm 46 contacts the contact 44, the waveform forming unit 39 “turns forward”. Yes! " Thereby, the driver can grasp the inclination of the fork in more detail.

Embodiment 4 FIG. 10 shows a configuration of a fork tilt notification device according to the fourth embodiment. This device is the device of the third embodiment shown in FIG. 8, in which the transmission between the tilt detection unit 35 and the speaker 15 is made wireless using a transmission unit and a reception unit that perform wireless transmission. In the transmission-side circuit, a switch 51, a tilt detection unit 35, and a transmission unit 52 are connected in series between both ends of the battery 11. On the other hand, in the receiving circuit, the switch 13, the waveform forming units 36 and 37, the receiving unit 54
Are connected in series, and the speaker 15 is connected to the waveform forming units 36 and 37. Battery 11, tilt detector 3
5, the switch 13, the waveform forming units 36 and 37, and the speaker 15 are the same as those used in the device of the third embodiment shown in FIG.

The transmitting circuit is mounted on the mast of the forklift, and the receiving circuit is mounted on the machine side of the forklift. When the switch 51 of the transmission side circuit is turned on during the cargo handling operation, a current flows through the transmission unit 52 via the contact 42 according to the inclination of the arm 46 of the inclination detection unit 35, or via one of the contacts 43 and 44. Transmitting section 5
2, a current flows. The transmitting section 52 wirelessly transmits the contact through which the current has flowed to the receiving section 54 of the receiving circuit using radio waves, infrared rays, or the like. In the receiving side circuit, the driver turns on the switch 13 as necessary, whereby the signal transmitted from the transmitting unit 52 is received by the receiving unit 54. When receiving the signal indicating that the current has flowed through the contact 42, the receiving unit 54 connects the waveform forming unit 36 to the battery 53, and as a result, is "neutral" according to the audio waveform formed by the waveform forming unit 36. Is emitted from the speaker 15. On the other hand, the receiving unit 54 is connected to the contact 43 or 4
When the signal indicating that the current has flowed is received via the control unit 4, the waveform forming unit 37 is connected to the battery 53, and as a result, the sound “tilted” according to the sound waveform formed by the waveform forming unit 37 is generated. Emitted from the speaker 15.

By performing wireless transmission between the transmitting unit 52 and the receiving unit 54 in this manner, wiring between the mast and the machine is not required, and the degree of freedom in arranging various devices is increased. As a result, a layout that takes into account work efficiency can be realized.

In the first to fourth embodiments, the tilt detector 12 or 35 is attached to the mast of the forklift, but may be directly attached to the fork. With this configuration, the present invention can be applied to a fork tilt type forklift in which only the fork is tilted without tilting the mast.

[0031]

As described above, according to the present invention, by distinguishing the frequency or content of the sound emitted from the sound generator, the inclination of the fork can be easily determined without the driver directly looking at the inclination detector. You can figure out. Therefore, the inclination of the fork can be grasped without lowering the efficiency of the cargo handling operation, and having a large degree of freedom in the arrangement position of the inclination detecting unit, and without hindering the work field of view and the layout for mounting other functional parts. Furthermore, if wireless communication is provided between the tilt detection unit and the sound generation unit, wiring between the mast and the machine base is not required, and the degree of freedom in arranging various devices is increased, and a layout that considers work efficiency more Becomes possible.

[Brief description of the drawings]

FIG. 1 is a circuit diagram illustrating a fork tilt notification device of a forklift according to Embodiment 1 of the present invention.

FIG. 2 is a front view showing a tilt detection unit of the fork tilt notification device according to the first embodiment.

FIG. 3 is a circuit diagram showing an equivalent circuit of a tilt detection unit of the fork tilt notification device according to the first embodiment.

FIG. 4 is a side view showing a forklift to which the fork tilt notification device according to the first embodiment is attached.

FIG. 5 is a perspective view showing a tilt lever provided with a switch.

FIG. 6 is a circuit diagram showing a fork tilt notification device according to a modification of the first embodiment.

FIG. 7 is a circuit diagram showing a fork tilt notification device according to a second embodiment.

FIG. 8 is a circuit diagram showing a fork tilt notification device according to a third embodiment.

FIG. 9 is a circuit diagram showing a fork tilt notification device according to a modification of the third embodiment.

FIG. 10 is a circuit diagram showing a fork tilt notification device according to a fourth embodiment.

FIG. 11 is a side view showing a forklift to which a conventional angle indicator is attached.

FIG. 12 is a side view showing a conventional angle indicator.

FIG. 13 is a front view showing a conventional angle display.

[Explanation of symbols]

 11, 33, 53 Battery 12, 35 Tilt detecting unit 13, 31, 51 Switch 14, 36 to 39 Waveform forming unit 15 Speaker 16, 41 Case 17, 42 to 44 Contact 18 Electric resistor 19, 45 Fixed shaft 20, 46 Arm 21, 47 Weight 23 Mast 24 Fork 25 Tilt cylinder 28 Tilt lever 29 Head guard 30 Headphone 32, 52 Transmitter 34, 54 Receiver

Claims (6)

[Claims] An inclination detecting section that shows a different electric resistance value according to the inclination of the fork; a waveform forming section that forms a sound waveform having a frequency corresponding to the electric resistance value of the inclination detecting section; A forklift informing device for a forklift, comprising: a sound generator for generating a sound toward a driver of the forklift based on the formed sound waveform. 2. The tilt detecting section includes: a variable resistor; an arm that is swingably provided and one end of which forms a movable contact of the variable resistor; and a weight attached to the other end of the arm. The device of claim 1 comprising: 3. A tilt detecting unit having a plurality of contacts and selecting one of the plurality of contacts according to the tilt of the fork, and a tilt detecting unit connected to the plurality of contacts of the tilt detecting unit and mutually tilting the fork. A plurality of waveform forming sections for forming different sound waveforms representing different contents, and for a forklift driver based on a sound waveform formed by the waveform forming section connected to the contact point selected by the inclination detecting section. And a sound generating unit for generating a sound. 4. An arm which is provided so as to be swingable and one end of which forms a movable contact that selectively contacts one of the plurality of contacts, and is attached to the other end of the arm. 4. The device of claim 3, comprising a weight. 5. The apparatus according to claim 1, wherein the tilt detector is attached to a mast of a forklift provided to be tiltable. 6. The apparatus according to claim 1, further comprising a transmission unit and a reception unit for performing wireless transmission, wherein a wireless connection is provided between the tilt detection unit and the audio generation unit.