JPH0511745Y2 - - Google Patents

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to an industrial vehicle equipped with outriggers on the front and rear or left and right sides of the vehicle. Regarding equipment.

(Prior art) Generally, industrial vehicles equipped with outriggers to stably support the load applied to the vehicle when performing cargo handling work, civil engineering work, etc., forget to store the outriggers (raise the outrigger base) after work. If the vehicle is run without such conditions, there will be problems such as damage to the outriggers, collapse of cargo, and the vehicle falling over.

Therefore, conventionally, as a solution to the above problem, when the outriggers are lowered, an inching valve for shutting off the torque converter clutch is mechanically operated in response to the lowering operation of the outriggers, thereby preventing the vehicle from moving. A safety device has been proposed to
(see publication). Specifically, the actuation lever that operates the inching valve and the detection member that comes into contact with each other when the outrigger base rises are connected via a mechanical linkage member consisting of a wire, an intermediate link member, a rod member, etc. On the other hand, the inching valve is normally biased by a spring to the operating side (clutch shutoff side) via the operating lever, and when the outrigger base is lowered, the inching valve is operated via the operating lever by the biasing force of the spring. , which is designed to prevent the vehicle from running.

(Problem that the invention aims to solve) However, since the conventional safety device described above is a system that blocks the torque converter clutch and prevents the vehicle from moving, it is limited to vehicle models equipped with a torque converter. Therefore, it is inferior in versatility. In addition, since it is linked to the clutch, the clutch is used frequently,
This causes problems such as wear of the clutch plate, rise in oil temperature, and damage to seals.Moreover, as the outrigger rises, the inching valve is switched to the clutch connection side, but generally the torque converter clutch connection range is the shift lever. Since the operating angle is extremely small, the inching valve is likely to be in a half-clutched state due to stretching of the wire that is the mechanical linking means or errors in assembly, which may cause the inching valve to become misaligned in its operating position. If a half-clutch condition were to occur, problems such as clutch wear would occur in the same manner as described above.

Furthermore, in actual work, in addition to problems caused by driving with the outrigger base lowered, similar problems can also occur if the outriggers are accidentally lowered while the vehicle is moving. However, conventional safety devices have not been able to solve this problem.

Therefore, an object of the present invention is to provide a safety device for lowering an outrigger of an industrial vehicle, which can solve the above-mentioned conventional problems.

(Means for Solving the Problem) The present invention to solve the above problem is to provide a detector for detecting the shift lever position for driving and an outrigger operation in an industrial vehicle equipped with outriggers on the front and rear or left and right sides of the vehicle. An electromagnetic opening/closing valve is provided in the hydraulic circuit for the outrigger, and operates to keep the hydraulic circuit closed at all times and open the hydraulic circuit in response to a detection signal from the detector when the shift lever is in the neutral position. A detector is installed near the shift lever to detect the outrigger, and the shift lever is always operated, and when the outriggers are in a lowered state, the shift lever is locked in a neutral position by a signal from the detector that detects this. The gist of this invention is that the outrigger safety device is constructed with a shift lock mechanism that operates as expected.

(Function) Therefore, when the vehicle is stopped and the shift lever is operated in the neutral position, the electromagnetic on-off valve opens the hydraulic circuit based on the detection signal from the detector, allowing the outrigger to be lowered, but when the vehicle is running At times, the electromagnetic on-off valve closes the outrigger's hydraulic circuit, so in this state, even if the outrigger control lever is accidentally operated in the lowering direction, the outrigger will be prevented from lowering. On the other hand, when the outriggers are up, the shift lock mechanism releases the lock on the shift lever, allowing the vehicle to run; however, when the outriggers are down, the shift lock mechanism is activated by the detection signal from the detector, and the shift lever is activated. Since the vehicle is locked in the neutral position, the vehicle is prevented from running in such a state.

(Example) Hereinafter, an example of the present invention will be specifically described based on the drawings. This embodiment is applied to a side forklift truck shown in FIG. A movable mast device 2 is attached to the. 3 is a fork attached to the mast device via a lift bracket so that it can be raised and lowered; 4 is an outrigger attached to the vehicle body frame 1 on the side where the fork 3 enters and exits; and 5 is a lifting operation of the outrigger 4; These are constructed similarly to conventional side forklift trucks.

As shown in FIG. 1, the outrigger 4 is connected by a conduit 7 to a switching valve 6 which is manually operated by an operating lever, and an electromagnetic on-off valve 8 is incorporated in the conduit 7. Further, a limit switch 9 for position detection is installed on at least one of the outriggers 4, and this limit switch 9
is turned OFF when the outrigger 4 comes into contact with the outrigger base 5 during its upward movement. In addition,
In FIG. 1, 10 is a hydraulic pump, 11 is a tank, and 12 is a relief valve.

On the other hand, FIG. 2 shows a travel operating system for controlling a torque converter clutch (not shown) (forward/reverse control) and a shift lock mechanism for holding the operating system in a neutral position. As shown in the figure, the traveling operation system includes a shift lever shaft 13 arranged vertically and rotatable, and a shift lever 14 attached to the upper end of the shift lever shaft 13.
and a link mechanism 15 that connects the shift lever shaft 13 and a control valve (not shown) of the torque converter, and by rotating the shift lever 14 in the longitudinal direction, the control valve is switched to control forward and backward movement. It's becoming like that.

Further, the shift lock mechanism 16 includes a shift lock rod 17 which is disposed laterally and is rotatable in the vicinity of the shift lever shaft 13.
A lock lever 18 is fixed to one end of the shift lock rod 17, and a fan-shaped lock cam 19 is fixed to one end of the shift lever shaft 13.
, an electromagnetic solenoid 20 for rotating the shift lock rod 17 toward the lock side, and a release spring 21 for releasing the lock. Specifically, the lock lever 18 and the lock cam 19 are arranged in a corresponding positional relationship. As shown in FIG. 3, the shift lever 14 is locked in the neutral position by engaging the lock lever 18 in a lock groove 19a formed at the center of the outer circumference of the lock cam 19. In this embodiment, the electromagnetic solenoid 20 is connected to an interlocking lever 22 fixed to the other end of the shift lock rod 17 via a spring 23, but the spring 23 may be omitted and the connection may be made directly.

In addition, in FIG. 1, 24 is the shift lever 1.
It is a limit switch for detecting the neutral position of 4.
It is turned on when the cam 25 provided on the shift lever shaft 13 comes into contact with it. Reference numeral 26 denotes a limit switch for confirming the shift lock, and it is turned off when it comes into contact with a cam 27 provided on the shift lock rod 17.

Next, an electric circuit for controlling the electromagnetic on-off valve 8 and the electromagnetic solenoid 20 will be explained based on FIG. As shown in the figure, the electromagnetic on-off valve 8 is connected to a battery 30 via a key switch 28, a limit switch 24 for detecting the shift lever position, and a b contact of a first relay 29, and an electromagnetic solenoid 20 is connected to a second relay. It is connected to the battery 30 via the a contact point 31. Also, key switch 2
8 is connected to the coil of the second relay 31 via a limit switch 9 for outrigger position detection, and connected to the coil of the first relay 29 via the limit switch 9 for outrigger position detection and the limit switch 26 for shift lock confirmation in series. is connected to.

This embodiment is configured as described above,
The effect will be explained below.

Now, when the key switch 28 is in the ON state and the outrigger base 5 of the outrigger 4 is in the raised position, the limit switch 9 is turned OFF by the outrigger base 5, so the electromagnetic solenoid 20 is OFF in this state. The shift lock mechanism 16 is in the unlocked state. That is, the lock lever 18 is released from the lock groove 19a of the lock cam 19 by the release spring 21. Therefore, in this state, by rotating the shift lever 14 forward or backward, the torque converter clutch can be actuated to move the vehicle forward or backward.

Also, outrigger base 5 of outrigger 4
is in the lowered position, the limit switch 9 remote from the outrigger base 5 is turned on, the coil of the second relay 31 is energized, the a contact of the second relay 31 is turned on, and the electromagnetic solenoid 20 is turned on. Power is applied. Therefore, due to the operation of the electromagnetic solenoid 20, the shift lever 1 is moved together with the shift lock rod 17 against the release spring 21.
8 is rotated, and the lock groove 19a of the lock cam 19
As a result, the shift lever 14 is locked in the neutral position. That is, outrigger base 5
is in the lowered state, shift lock mechanism 1
6 makes it impossible to operate the shift lever 14, and the vehicle will not run with the outrigger base 5 lowered.

On the other hand, when the shift lever 14 is operated to the forward or reverse position and the vehicle is running, the limit switch 24 for detecting the shift position moves away from the cam 25 and turns OFF.
Regardless of whether the contact is in the ON or OFF state, the energization to the solenoid of the electromagnetic on-off valve 8 is cut off, and the electromagnetic on-off valve 8 is switched to the passage closing side. Therefore, since the outrigger 4 is locked in a circuit, the outrigger base 5 will not operate even if the driver accidentally operates the switching valve 6 while the vehicle is running.

Furthermore, when the vehicle is stopped and the shift lever 14 is operated to the neutral position, the shift lock mechanism 16 is locked as described above, but at this time, the limit switch 26 for lock confirmation is activated by the cam 27.
The coil of the first relay 29 is not energized, and the coil of the first relay 29 is turned off by contact with the
The ON state of the b contact is maintained. Furthermore, when the shift lever 14 is operated to the neutral position, the limit switch 24 for detecting the shift position is also turned on by contacting the cam 25, so that the solenoid of the electromagnetic on-off valve 8 is energized, and the electromagnetic on-off valve 8 is connected to the circuit. Switched to open side. Therefore, in this state, the outriggers 4 can be operated by switching the switching valve 6 to the downward direction.

According to this embodiment, when the shift lever 14 is not locked due to a failure of the shift lock mechanism 16 in the state where the shift lever 14 is operated to the neutral position after the vehicle has stopped, the limit switch 26 for lock confirmation is activated. The outrigger 4 is not lowered due to the action of the outrigger 4.
That is, when the shift lock mechanism 16 is not operated, the limit switch 26 for lock confirmation is activated.
is turned ON, and in this state, the outrigger base 5 moves downward and separates from the limit switch 9, and at the same time the limit switch 9 turns ON.
The coil of the first relay 29 is energized, and its b contact is switched off. As a result, the power supply to the solenoid of the electromagnetic on-off valve 8 is cut off, and the electromagnetic on-off valve 8 is switched to the passage closing side, so that the lowering of the outrigger base 5 is prevented.
This makes it possible to recognize malfunction of the shift lock mechanism 16.

Further, since the electromagnetic on-off valve 8 in this embodiment uses a normal OFF type, when a failure occurs in the electrical system of the electromagnetic on-off valve 8, the outrigger 4 becomes inoperable. Furthermore, since the shift lock mechanism 16 is released using a spring 21, even if the electric circuit breaks down, there is no problem in running the vehicle.

Although this embodiment uses a method in which the shift lever 14 is locked in a vehicle equipped with a torque converter, it is also implemented in a vehicle equipped with a foot-operated clutch in which the shift lever (change lever) is locked in the neutral position. It is possible to do so.

(Effects of the invention) As described in detail above, according to the invention, it is possible to prevent the vehicle from moving when the outriggers are in the lowered state, and it is also possible to prevent the vehicle from moving when the outriggers are in the lowered state, and to prevent the driver from accidentally levering the outriggers to the lowering side while driving. This can prevent damage to the outriggers, collapse of cargo, overturning of the vehicle, etc.

Moreover, the present invention prevents the vehicle from moving by locking the shift lever in the neutral position when the outriggers are in the lowered state. Unlike conventional methods, this method is highly versatile and can be applied not only to vehicles equipped with a torque converter but also to vehicles equipped with a foot-operated clutch, and it also avoids the drawbacks of conventional methods that disconnect the torque converter clutch. be,
Problems such as clutch plate wear, oil temperature rise, and seal damage can be solved.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention: Fig. 1 is a hydraulic circuit diagram of the outrigger, Fig. 2 is a perspective view showing the travel operation system and its shift lock mechanism, Fig. 3 is a detailed view of the shift lock part, and Fig. 4 is a hydraulic circuit diagram of the outrigger. An electric circuit diagram of the electromagnetic on-off valve and the electromagnetic solenoid, and FIG. 5 is an overall side view of the side forklift truck. 4...Outrigger, 5...Outrigger base, 6...Switching valve, 8...Solenoid on-off valve, 9...Limit switch, 13...Sit lever shaft,
14...Shift lever, 16...Shift lock mechanism, 18...Lock lever, 19...Lock cam, 20...Electromagnetic solenoid, 24...Limit switch, 26...Limit switch.

Claims (1)

[Scope of utility model registration request] In an industrial vehicle equipped with outriggers on the front and rear or left and right sides of the vehicle, a detector for detecting the position of the shift lever for driving and a hydraulic circuit for operating the outriggers are provided, and the hydraulic circuit is always kept in a closed state, and the above-mentioned An electromagnetic on-off valve that operates to open the hydraulic circuit based on a detection signal from a detector when the shift lever is in the neutral position, a detector that detects the position of the outriggers, and a detector that is installed near the shift lever and that is normally operated by the shift lever. and a shift lock mechanism that operates to lock a shift lever in a neutral position in response to a signal from a detector that detects the lowered state of the outriggers.