JPH02193897A - Device for controlling throttle interlocked with cargo-handling - Google Patents

Abstract

PURPOSE:To securely control a valve by composing the device so that when a cargo-handling lever is operated, without operating an accelerator pedal, a throttle valve is opened or closed via a valve ink mechanism; on the other hand, when the accelerator pedal is operated, without moving the cargo-handling lever, the throttle valve is opened or closed via the valve link mechanism. CONSTITUTION:When a forklift is traveled, by operating an accelerator pedal, a valve link mechanism 4 is operated to open or close the throttle valve of an engine. In this case, a cargo-handling ink mechanism 3 is operated, and a cargo-handling lever is operated. As a result, an oil control valve 29 is not at all influenced by the operation of the accelerator pedal. Next, at the time of cargo-handling operation, both the cargo-handling link mechanism 3 and the accelerator rod and valve link mechanism 4 are operated for opening or closing the throttle valve. In this case, the accelerator pedal is not operated.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention is a forklift truck in which the throttle valve of the engine is operated by operating a cargo handling lever.

The present invention relates to a throttle control device that can automatically control opening and closing.

[Prior art]

Forklifts perform cargo handling work by driving a hydraulic pump with an engine and operating a cargo handling lever and an oil control valve to channel the hydraulic oil generated by the hydraulic pump. and.

The speed of this cargo handling operation, that is, the speed of lifting, lowering, forward tilting, and backward tilting of the load using the lift cylinder and tilt cylinder, is generally controlled by controlling the engine output with the accelerator pedal.
This is done by operating the cargo handling lever and oil control valve.

However, when carrying out cargo handling work while driving, the accelerator pedal is operated, which increases the number of revolutions of the hydraulic pump and increases the hydraulic pressure, so there is no problem with cargo handling work. However, when the car is not driving, the accelerator pedal 1 because you do not operate
Low hydraulic pressure (unable to carry out cargo handling work).

Therefore, conventionally, when the vehicle is not driving, the transmission is generally kept in the neutral state.

He depresses the accelerator pedal and increases the engine speed. However, such an operation requires the driver to be in the neutral state as described above, and to simultaneously operate the cargo handling lever while depressing the accelerator pedal, making the cargo handling work complicated and causing fatigue to the driver.

Therefore, in order to deal with such problems, the
-The cargo handling speed of the forklift shown in Publication No. 7900! An I control device has been proposed.

This device has an accelerator pedal 9 as shown in FIG.
5 to wire 951. In addition to the means for operating the throttle valve 93 via the throttle lever 931, the throttle valve 93 is provided with an auxiliary lever 932. Then, the auxiliary lever 932 is connected to the electromagnetic clutch 97 via the wire 923. The electromagnetic clutch 97
receives a signal from the detection switch 941 indicating that the transmission 94 is in the neutral position, and connects the wire 923 and the wire 92 interlocked with the lift lever 91.
Connect with 1. When not in the neutral position, both wires 923 and 921 are disconnected.

However, in this device, the transmission 9
When lift lever 91 is operated when lever 92.4 is in neutral, lever 92.4 is operated. Wire 921. Electromagnetic clutch 97. Wire 923. Throttle valve 93 opens via auxiliary lever 932. and.

As the engine output increases by five revolutions, the oil control pulp 961 operates and the lift cylinder 96 rises.

Further, among the cargo handling levers, the tilt lever is configured in the same manner, and the output speed of the engine is controlled in the same manner as described above during the tilt operation.

In this way, the above device can be used even when not traveling.

Even if the accelerator pedal 95 is not operated, the desired engine rotation speed, that is, the hydraulic pump rotation speed can be obtained by operating only the cargo handling lever.

[Problem to be solved]

However, in the above device, when the transmission is in a position other than the neutral position, the engine speed cannot be increased by operating the cargo handling lever even if the vehicle is stopped, which makes cargo handling operations inconvenient. For example, if you attempt to handle cargo on a slope with the transmission in gear, you must step on the brake, operate the accelerator pedal, and operate the cargo handling lever.

Furthermore, since a wire 923 is used between the auxiliary lever 932 of the throttle valve and the electromagnetic clutch 97, when the accelerator pedal 95 is depressed.

The wire 923 becomes greatly bent. Therefore,
A space for wire escape is required depending on the amount of wire.

In view of these conventional problems, the present invention provides a cargo-handling interlocking throttle control device that can automatically open and close a throttle valve by operating a cargo-handling lever using a link mechanism.

[Means for solving problems]

The present invention opens and closes the throttle valve to control engine output and rotation speed. A forklift includes a throttle control device for controlling the load, a cargo handling lever for operating cargo handling operations such as lift and tilt, and an oil control valve operated by the cargo handling lever, wherein the throttle control device includes a valve connected to the throttle valve. a cargo handling link mechanism, an accelerator pedal connected to the valve link mechanism, and a cargo handling link mechanism provided between the valve link mechanism and the cargo handling lever, the accelerator pedal being operated when the cargo handling lever is operated. A cargo-handling linked throttle characterized in that the throttle valve is opened and closed via the valve link mechanism without moving the throttle valve, and the throttle valve is opened and closed via the valve link mechanism without moving the cargo-handling lever when the accelerator pedal is operated. Located in the control device.

In the present invention, the cargo handling lever is an operating lever for performing cargo handling operations such as lift operation and tilt operation. The cargo handling lever is connected to an oil control valve and also to the cargo handling link mechanism.

To simultaneously perform cargo handling operation and opening/closing of a throttle valve.

The valve link mechanism is a mechanism that is operated by an accelerator pedal or a cargo handling lever to open and close a throttle valve. Therefore, an accelerator pedal and a cargo handling link mechanism are connected to the valve link mechanism (first
(see figure). The valve linkage is connected to a throttle valve.

When the cargo handling lever for lift, tilt, etc. is operated, the cargo handling link mechanism transmits the operating force to the valve link mechanism to open and close the throttle valve.On the other hand, when the accelerator pedal is operated, the cargo handling lever moves. It has a function to prevent

Further, the valve link mechanism has a rotatable shaft to which an accelerator link is fixed, one end of the accelerator rod of the cargo handling link mechanism is fixed to the shaft, and the other end of the accelerator link is a wire. Connected to the throttle valve via.

Further, the accelerator link may be configured to rotate together with the shaft when the accelerator pedal is pressed (see FIG. 1).

Further, in the cargo handling link mechanism, a plurality of cargo handling levers such as lift levers, tilt levers, etc. are connected to the accelerator rods so that they do not interfere with each other.

Also, the cargo handling lever does not operate when the accelerator pedal is operated (that is, the oil control valve is not operated).
It can also be a link mechanism.

(Function) In the throttle control device of the present invention, when the forklift is traveling, by operating the accelerator pedal, the valve link mechanism is activated to open and close the throttle valve of the engine.

The cargo handling link mechanism operates and the cargo handling lever does not move, so the oil control valve is not affected by the operation of the accelerator pedal.

Next, during cargo handling operation, the cargo handling lever is operated to operate the cargo handling link mechanism, the accelerator rod, and the valve link mechanism to open and close the throttle valve. At this time, the accelerator pedal does not move.

These effects occur even when the transmission is in neutral and not driving, when the transmission is in gear on a slope and stopped with the brakes pressed, or when the forklift is stopped as described above. The same applies even while driving.

Note that while the forklift is running, the throttle valve is opened and closed by operating the accelerator pedal, so the throttle valve is rarely opened and closed by the cargo handling lever as described above.

〔effect〕

As described above, in the second aspect of the present invention, the opening and closing of the throttle valve can be controlled by operating the cargo handling lever, regardless of whether the transmission is in the neutral state. Also, for opening and closing the throttle valve using the cargo handling lever.

Since a link mechanism is used, the wire does not become loose as in conventional wire operation, and the throttle valve can be controlled reliably.

Therefore, according to one aspect of the present invention, the cargo handling speed can be adjusted only by operating the cargo handling lever without operating the accelerator pedal during cargo handling, and the operation becomes easy.

Furthermore, driver fatigue is thereby reduced. Furthermore, since the engine speed is not increased more than necessary, fuel can be saved.

〔Example〕

First Embodiment A cargo handling interlocking throttle control device according to an embodiment of the present invention will be described with reference to FIGS. 1 to 10.

As shown in the overall conceptual diagram of FIG. 1, this example device includes a lift lever 11 and a tilt lever 21 as cargo handling levers, and a cargo handling link mechanism 3.

It has a valve link mechanism 4, an accelerator mechanism 5, and a throttle lever 481.

First, to outline the overall function, the lift lever 1
1 or the tilt lever 21, the oil control valve 29 is operated as in the conventional case, and a lift or tilt operation is performed.

At the same time, by operating both levers 11 and 21, the accelerator rod 3 is moved through the cargo handling link mechanism 3.
1,32 is drawn. Due to this.

The shaft 41 rotates together with the boss 42 of the valve link mechanism 4, and the accelerator link 44 also rotates.

Pull the wire 47. Therefore, the slot lever 481 connected to the tip of the wire 47 is pulled and the throttle valve of the engine 48 is opened.

Furthermore, when the accelerator pedal 51 (FIGS. 9 and 10) of the accelerator mechanism 5 is pushed downward in order to drive the forklift, the roller 53 is pushed and the boss 43 rotates via the rod 52. The rod 431 provided on the boss 43 rotates and pushes the accelerator link 44, so that the throttle valve is opened via the wire 47 as described above.

Therefore, in the above, the rod 5 of the accelerator link 5
2 is attached to the boss 43, which is rotatably pivoted to the shaft 41. Therefore.

Even if the shaft 41 is rotated by operating the lift lever 11 or the tilt lever 21, the rod 52 does not move.Conversely, even if the rod 52 is actuated by the accelerator link 5, the cargo handling system connected to the accelerator rod 32 does not move. The link mechanism 3 is connected to the lift lever 11. Since the tilt lever 21 is not moved, the oil control valve 29 does not operate at all.

In addition, in FIG. 1, numerals 411 and 412 are.

This is a bracket that supports the shaft 41. Also, 4
Reference numeral 5 denotes a plate for urging the accelerator rod 431 in the throttle valve closing direction by a spring 451.

Next, each mechanism will be explained in turn.

First, regarding the mechanism of lift operation system I, see Figures 2 and 4.
To explain using a diagram, the lift lever 11 includes a lift lever plate 1 pivotally connected to a cargo lever support shaft 10.
Attach it to the base of 2. The lower end I31 of the lift lever plate 12 is connected to the oil control valve 2.
9 (Fig. 4) is pivotally connected to the lift loft 13.

Also.

A rod 14 is connected to the tip end 121 of the lift lever plate 12 via a ball cylinder 142. The lower end of the rod 14 is connected to the tip of a link 151 of the main link 15 via a ball cylinder 141.

In addition, a ball cylinder 312 is installed at the tip of the main link 15.
The accelerator rod 31 is connected to the accelerator rod 31 via the axle rod 31, and the accelerator loft 32 is connected to the accelerator rod 31 via a ball cylinder 311. The tip of the accelerator rod 32 is fixed to a boss 42 fixed to the shaft 41 of the valve link mechanism 4, as shown in FIG. The base of the main link 15 is pivotally connected to the shaft 30 together with the base of a tilt-type main link 25 to be described later.

Next, the tilt operation system 2 will be explained using FIGS. 3 and 4. The tilt lever 21 is attached to the base of the tilt lever plate 22. As shown in FIG.

The tilt lever plate 22 is pivotally connected to the cargo handling lever support shaft 10 to which the lift lever plate 12 is pivotally connected. Further, a tilt rod 23 whose lower end 231 is connected to an oil control valve 29 (FIG. 4) is pivotally attached to a substantially central portion of the tilt lever plate 22. Further, a rod 24 is connected to the tip end 221 of the tilt lever plate 22 via a ball joint 243. The lower end of the rod 24 is connected to a link 26 provided inside the main link 25 via a ball cylinder 241.

Further, the base of the main link 25 is pivotally connected to a shaft 30 provided on a bracket 301 together with the main link 15 of the lift system. Also, bracket 3 near bracket 301
02, a small link 27 is pivotally connected by a shaft 271. The small link 27 has pins 272 and 273 (
(See Figure 8).

Further, the main link 25 is connected to the main link 1 of the accelerator system via a pin 251, as shown in FIG. 8, which will be described later.
5 to the connected ball joint 312. The ball joint 312 is connected to the accelerator rod 31. Therefore, when either the lift lever 11 or the tilt lever 21 is operated, the accelerator rod 31 is pulled upward and rotates the shaft 41 of the valve link mechanism 4 via the accelerator rod 32.
Pull the slot lever 481 to open the 1st throttle valve (
.

Next, regarding the cargo handling link mechanism, the above-mentioned lift operation system 1
Main link 15. and main link 25 of tilt operation system 2
This will be explained with reference to FIGS. 5 to 8.

5, 6, and 7 show the main link 15 when the lift lever 11 and tilt lever 21 are operated. It shows the movement of the main link 25 and these related links. Therefore, FIG. 5 shows the states of both links and related links when the lift of the forklift is lowered and when the tilt lever is tilted forward, and FIG.
This shows the state when the lift of the forklift is raised and the tilt lever is tilted backward. FIG. 7 shows the lift lever 11. The state of the link is shown when the tilt lever 21 is in the neutral state. These operations will be described later.

Further, the main links 15, 25, etc. are connected as shown in FIG. That is, the shaft 30 is horizontally installed in the brackets 301 and 302 provided on the base of the forklift as described above, and the main link 15 of the lift system is attached to the shaft 30. Link 151 and tilt main link 25
．． The link 26 is pivotally connected. Also 1 above bracket 302
A small link 27 is pivotally connected to. The pin 272 of the small link 27 faces the link 26, and the pin 273 faces the main link 25.

Next, the accelerator mechanism 5 will be explained using FIGS. 9 and 10. The accelerator mechanism 5 includes an accelerator pedal 5
1, a roller 53 disposed below it, and a rod 52 . L-shaped rod 4 provided via boss 43
It consists of 31 and more. The boss 43 is rotatably connected to the shaft 41 of the valve link mechanism 4. Further, the tip of the rod 431 is in contact with a plate 45 biased by a spring 451. Also, acid rod 43
1 faces the accelerator link 44 fixed to the shaft 41 with a slight gap (Fig.
0), a stopper 511 is provided on the lower surface of the accelerator pedal 51.

This example device is configured as described above.

Each mechanism has the following effects. Regarding the overall operation, please refer to 1 above as well.

First of all, regarding the lift operation system 1, see Figures 2 and 4~
As shown in FIG. 8, when raising the lift of a forklift, pull the lift lever 11 toward you (rightward in FIG. 2). This causes the lift lever plate 12 to rotate about the shaft 10, and the lift rod 13 and pull the lift spool (path shown) of the oil control valve 29, the fork provided on the lift begins to rise.

Then, by operating this lift lever 11.

At the same time, rod 14. link 15 of the cargo handling link mechanism 3;
The accelerator rods 31, 32 are pulled, the shaft 41 rotates in the R direction as described above, the throttle valve is opened, and the rotational speed of the engine 48 increases. That is, by the above operation of the lift lever 11, the link 151 of the main link 15 is pulled up by the rod 14, the nut 140 provided on the link 151 comes into contact with the main link 15, and the tip of the main link 15 is pulled up. accelerator rod 3132
is drawn (see Figure 7).

Next, when lowering the lift, lift lever 11
This causes the lift lever plate 121 to rotate and push down the lift rod 13, lowering the lift spool of the oil control valve 29 and lowering the fork. At this time, lift lever 11
The operating power is.

Since the main link 15 of the cargo handling link mechanism 3 does not rotate, the rotation is not transmitted to the accelerator rod 31, so the opening/closing state of the throttle valve does not change, and the rotational speed of the engine does not change.

That is, due to the rotation of the lift plate 12, the rod 1
4 is lowered, but the link 151 connected to the lower end of the rod 14 only rotates downward as shown in FIG. 5, and the main link 15 is in the same state as in the neutral state (FIG. 7). Therefore, the axel rods 31, 32 do not move.

Next, regarding the tilt operation system 2, as shown in FIGS. 3 to 8, when tilting the forklift mast backward, the tilt lever 21 is pulled toward you (to the right in FIG. 3). The lever plate 22 rotates about the shaft 10, pulls up the tilt rod 23, pulls the tilt spool of the oil control valve 29, and tilts the mast rearward. At the same time, the main link 25 of the cargo handling link mechanism 3. accelerator rod 31
．． A throttle valve is opened via 32.

Engine speed increases.

That is, by operating the tilt lever 21.

As shown in FIG. 3, when the rod 24 is pulled up, the link 26 rotates about the shaft 30, and as shown in FIG.
As shown in FIG. 8, the nut 242 of the link 26 hits the main link 25, and.

The main link 25 also rotates around the shaft 30.

The end of the bottle 2 is raised and attached to the main link 25.
51 lifts the main link 15 of the lift system. Therefore, as described above, the accelerator rods 31, 32 connected to the main link 15 are pulled.

Engine speed increases.

In addition, when tilting the mast forward, as shown in FIG. 3, when the tilt lever 21 is pushed (leftward in the figure), the tilt lever plate 22 rotates about the shaft 10, pushing down the tilt rod 23, and pushing down the oil control valve 29. Press the tilt spool to tilt the mast forward. At the same time, the throttle valve is opened via the main link 25 degree accelerator rod 31, 32 of the cargo handling link mechanism 3, and the engine speed increases.

That is, by operating the tilt lever 21.

As shown in FIG. 3, when the rod 24 is pushed down,
The link 26 rotates around the shaft 30. As a result, as shown in FIGS. 5 and 8.

The lower surface of the link 26 hits the bin 272 of the small link 27,
The small link 27 rotates around a shaft 271. Then, the pin 273 at the other end of the small link 27 is attached to the main link 25.
push up. Therefore, the bin 2 provided on the main link 25
51 pushes up the main link 15 of the lift system, and pulls up the accelerator rods 31 and 32 connected to the main link 15. As a result, the engine speed increases.

Next, via the accelerator mechanism 5, as shown in FIGS. 9, 10, and 1, when the accelerator pedal 51 is depressed to drive the forklift, the roller 53 is pushed, and the rod 52
rotates the boss 43 in the R direction (FIG. 1). Along with this, the rod 431 provided on the boss 43 moves against the spring 4.
51, rotates in the R direction and pushes the accelerator link 44. As a result, the accelerator link 44 rotates together with the shaft 41, pulls the wire 47, and opens the throttle valve. Increase engine speed.

In addition, in the above, the shaft 41 is the accelerator link 4
4, and pushes up the accelerator rod 32 and 31 (Fig. 1).Even if the accelerator rod 31 is pushed up, the main link 15 idles around the shaft 30 (the second ), therefore, the lift system rod 14. The tilt rod 24 does not lift up, and the lift lever 11. The tilt lever 12 does not move and has no effect on the oil control valve.

As described above, according to this example device, the cargo handling speed can be adjusted simply by operating the cargo handling lever without operating the accelerator pedal, and the forklift can be easily operated.

Furthermore, driver fatigue is thereby reduced. Furthermore, since the engine speed is not increased more than necessary, fuel can be saved.

Furthermore, in this example, unlike the prior art described above, the cargo handling link mechanism and the throttle valve lever are not connected by a wire, so no space is required for the wire to escape. Furthermore, the relationship between the cargo handling lever operation and the engine speed can be easily adjusted by changing the length between the ball joint and the rod.

Also, when the transmission is not in neutral.

Since the mechanism of the present invention can be operated, there is no need to return the shift lever to neutral during cargo handling.

In addition, the transmission link mechanism that transmits the operation of the cargo handling lever to the accelerator rod is compact because it is a link mechanism, and can be stored compactly between the front frame of the forklift and the cargo handling lot. Not become.

The appearance is also good.

Second Embodiment In this example, the throttle valve openings performed by the lift lever, tilt lever, and accelerator pedal are determined by the link ratio and link shape.
This is an example. This will be explained using FIGS. 11 to 13.

First, regarding the lift lever, as shown in Figure 11, there is no need to increase the engine (E/G) rotation speed when the lift is lowered (left side in the figure).

Even if the lift lever is moved in the downward direction, the accelerator rod 32 (FIG. 1) is not pulled.

On the other hand, when the lift is being raised, the engine speed is not increased near neutral so that it is easier to make small adjustments to the oil control valve during the lift operation.

Provide a play C part. This play can be adjusted by adjusting the lot 14 ball joint 142 (Fig. 2).

This is done by changing the distance between the lift lever plate and the main link.

Next, regarding the tilt lever, since the tilt speed is determined by the oil flow control valve in the cargo handling circuit and reaches its maximum when the engine speed is about 50% or higher, as shown in Figure 12, the Even when the tilt lever operation amount is 00%, the engine opening degree is suppressed to about 50% to prevent unnecessary fuel consumption.

Also, in the vicinity of neutrality, it is easy to perform fine tilt operations, similar to the case with the lift lever.

A play C portion is provided that does not increase the engine speed.

Next, regarding the accelerator pedal, as shown in FIG. 13, the accelerator pedal and throttle valve opening are set in the same way as in the conventional case.

[Brief explanation of the drawing]

Figures 1 to 10 show the throttle control device of the first embodiment, Figure 1 is an overall explanatory diagram, Figure 2 is a side view of the link mechanism of the lift operation system, and Figure 3 is the link mechanism of the tilt operation system. Figure 4 is a rear view of the lift and tilt system link mechanism, Figures 5, 6, and 7 show the operating status of each link in the cargo handling link mechanism, and Figure 5 is the lowering of the lift and before tilting. Figure 6 shows when the lift is raised and tilted backwards. FIG. 7 is a front view showing the lift-neutral and tilt-neutral states, respectively, and FIG. 8 is a rear view of the cargo handling link mechanism. Figures 9 and 10 are side views and plan views of the accelerator mechanism, Figures 11 to 13 are diagrams showing the relationship between the lift lever 3 tail lever, accelerator pedal, and throttle valve opening, and Figure 14 is FIG. 1 is an overall explanatory diagram of a conventional throttle control device. ■1. ．． Lift system. 11, Lift lever 12, Lift lever plate. 13°0. lift lot. 14.24. ,, Rod. 15.253. , main link 219. Tilt system. 21, Tilt lever 22, Tilt plate. 23,, tilt rod. 29. Oil control valve. 303. Link mechanism for cargo handling. 31.32. ,,Axelrod. 490. Link mechanism for valves. 4I...shaft. ４４、、、Accelerator link. 48, engine. 481, Throttle valve lever 5° accelerator mechanism. 51° accelerator pedal. 52° rod. Embedded by Toyoda Automatic Loom Works Co., Ltd.

Claims (1)

[Scope of Claims] A throttle control device that opens and closes a throttle valve to control engine output and rotation speed, a cargo handling lever that operates cargo handling operations such as lift and tilt, and an oil control valve that is operated by the cargo handling lever. In the forklift, the throttle control device includes a valve link mechanism connected to the throttle valve, an accelerator pedal connected to the valve link mechanism, and a cargo handling lever provided between the valve link mechanism and the cargo handling lever. It has a link mechanism, which opens and closes the throttle valve via the valve link mechanism without operating the accelerator pedal when the cargo handling lever is operated, and on the other hand, opens and closes the throttle valve via the valve link mechanism without moving the cargo handling lever when the accelerator pedal is operated. 1. A cargo handling interlocking throttle control device, characterized in that the throttle valve is opened and closed through the cargo handling interlocking throttle control device.