JPH0219011B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a hinge operation safety device that allows a cargo box to be completely tilted in each direction in a three-turn dump truck.

(Prior art) Conventionally, in a three-turn dump truck, hinges are provided at four locations on the front, rear, left, and right between the loading platform and the loading box, and the hinge is composed of a hinge shaft, a shaft receiving member, and a hook. The cargo box is rotated in accordance with the direction in which the cargo box is tilted, the corresponding hinge shaft is unlocked, and the hydraulic cylinder is extended using the cargo box tilting operation lever to tilt the cargo box in the desired direction. (For example, see Japanese Patent Application Laid-Open Nos. 56-50822 and 1982-103629).

(Problems to be Solved by the Invention) In the above-described structure, the hook is positioned in either the locked state or the released state, but this prevents dirt and sand from getting into the hinge part and damaging the body. When the cargo box is not in the completely laid down position due to deformation (warping, sagging), etc., that is, when the cargo box is not in the traveling position, the hooks are in a state between the secured state and the released state (i.e. If the hook is half-hung on the hinge and the cargo box is tilted using the cargo box tilting operation lever, there is a risk that the cargo box may fall from the undercarriage.

Therefore, the present invention has been developed to prevent the careless raising of the cargo box when the cargo box is not in a completely laid down position, that is, when it is not in the running position, and to safely perform the tilting operation of the cargo box. The purpose is to provide a hinge operation safety device for dump trucks.

(Means for Solving the Problems) In order to achieve the above object, the present invention provides hinge shafts at four locations on the front, rear, left and right sides of either the vehicle chassis or the bottom of the cargo box, and the hinge shafts at four locations on the front, rear, left and right of the other. In a three-turn dump truck, the hinge is constructed by providing a shaft receiving member and a hook, respectively, and the tilting operation of the cargo box is controlled by the cargo box tilting operation lever. a cargo box detection means for detecting whether or not the cargo box is completely laid down; a hinge switching actuator for selectively operating the hinge between a locked state and a released state; and the hinge switching actuator for selectively operating the hinge between a locked state and a released state. a selection switch for operating the cargo box tilting operation lever in accordance with each tilting direction, a detection device for detecting a fully locked state, a completely released state, and an incompletely locked state of the hinge switching actuating device; lashing means for securing the cargo box in the prone position, and when the cargo box detection means detects that the cargo box is not in the completely fallen position, the selection switch is disabled and the selection switch is activated. The present invention is characterized in that when the detection device detects that the hinge corresponding to the selected tilting direction is in an incompletely locked state, the lashing means is activated to disable the cargo box from tilting.

(Function) When the cargo box detection means detects that the cargo box is not in the completely laid down position, the selection switch is disabled. At the same time, when the detection device detects that the hinge corresponding to the tilting direction selected by the selection switch is in an incompletely locked state, it activates the lashing means to disable the tilting of the cargo box. .

(Embodiment) Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. In FIG. While the hinge shafts 3 in the directions are fixed, cross members 7 are provided at the front and rear of the chassis 4, and a shaft receiving member 5 is fixedly provided at the tip of the cross member 7 in correspondence with each hinge shaft 3. A hook 6 is rotatably supported on 5 (see FIG. 4), and hinges are provided at four locations between the bottom of the cargo box 1 and the chassis 4, front, rear, left, and right.

As shown in FIG. 2, a reed switch main body 9a is provided via a first bracket 8 to a cross member 7 having a closed section structure extending in the vehicle width direction of the vehicle chassis 4, while a cargo box 1 corresponding to the cross member 7 is provided. A magnet 9b is provided via a second bracket 11 to another cross member 10 having a closed cross-section structure extending in the vehicle width direction at the bottom. The reed switch main body 9a and the magnet 9b constitute a reed switch 9, which is a cargo box detection means for detecting whether the cargo box 1 is in a completely laid down position, that is, whether it is in a running posture. The reed switch 9 is turned on when the cargo box 1 is in a traveling position.

Reference numeral 12 denotes a cargo box tilting operation lever for controlling the tilting operation of the cargo box 1, and is provided in the driver's cab. As shown in detail in FIG. 3, this cargo box tilting operation lever 12 is rotatably mounted on a pivot shaft 13, and has a U-shaped engagement ring 14 and an L-shaped cross-sectional abutment in the middle. Members 15 are each fixedly provided.

By the way, a limit switch 18 for detecting the tilting state of the cargo box tilting operation lever 12 is attached to the upper part of the mounting plate 17 installed upright on the board 16 in the driver's cab, and the movable terminal 18a of the limit switch 18 is connected to the abutting member 1.
5 are now touching each other. When the cargo box tilting operation lever 12 is at the cargo box tilting position P1, the limit switch 18 is closed.

On the other hand, a lock lever 14 serving as a lashing means is pivotally attached to the lower part of the mounting plate 17 so that its base end can be rotated about a pivot shaft 19, and a lock portion 14a at the tip is connected to the cargo box tilting operation lever 12. When in the prone position P1, it is configured to engage with the engagement ring 14 and make the operating lever 12 inoperable.
Further, a locking piece 21 is protruded from the lock lever 14, and a spring 26 is interposed between the locking piece 21 and the base plate 16 (spring hook 22), so that the lock lever 20 is normally locked in a counterclockwise direction. The portion 20a is biased in the direction of separating from the engagement ring 14, and the lock lever 20 is pushed away from the engagement ring 14.
In the engaged state, it is biased clockwise. Furthermore, an elongated hole 20c is formed in the protrusion 20b near the base end of the lock lever 20, and an engagement pin 25 provided at the tip of the rod 24, which is retracted by excitation of the solenoid 23 as a driving means, is inserted into the elongated hole 20c. is loosely fitted. This solenoid 23
is attached to the mounting plate 17 at a position below the limit switch 18.

By the way, each of the above-mentioned hooks 6 is for locking the hinge shaft 3 to the shaft receiving member 5, and is always urged to the released state by a spring (not shown), and is rotatably supported on the shaft receiving member 5. The stopper 31 is held at the locking position P2.

This stopper 31 is linked to a hinge switching actuating device 33 via a rod member 32 inserted into the cross member 7, and this hinge switching actuating device 33 is connected to an electric motor M and a hinge switching actuating device 33 connected to the electric motor M. Although a detailed explanation will be omitted, rotational motion is converted into linear reciprocating motion in the reducer 34, and the rod member 32 is connected to the output shaft of the reducer 34. connected. As a result, the reciprocating movement of the rod member 32 by the hinge switching actuating device 33 allows the hook 6 to be rotated between the stop position P3, which holds the hook 6 at the locking position P2, and the release position P4, where the hook 6 is released from the lock. The stopper 31 is configured to rotate between the stopper 31 and the stopper release position P5.

Further, an operation panel 41 is provided in the driver's cab, and this operation panel 41 includes a rear dump push button PB ₁ and a left dump push button as selection switches for operating the hinge switching actuating device 33 in accordance with each tilting direction.
PB ₂ , a push button PB ₃ for dumping on the right side, a push button PB ₄ for lamp inspection, and a push button PB ₅ for reversing are built-in. Furthermore, a control box 42 for housing a control system and an alarm buzzer 43 are provided in the driver's cab.

Next, the control system of the above device will be explained with reference to FIGS. 6 and 7. SW1 is the engine key switch, and as mentioned above, the cargo box tilting operation lever 12 is in the cargo box tilting position P1. It is a limit switch that operates when F is a fuse, XR is a power relay, and has contacts xr. R ₁ , R ₂ ,
R ₃ is a relay, which connects the pushbuttons PB ₁ , PB ₂ and PB ₃
are connected in series to the relay contacts r ₁ , r ₂ , respectively.
It has r ₃ .

M ₁ , M ₂ , M ₃ , and M ₄ are electric motors of the hinge switching actuating device 33 described above, and are arranged according to the mounting positions shown in FIG. 7. and,
The electric motors M ₁ , M ₂ , M ₃ , M ₄ have movable terminals 55, 56, 57, 58, 59, and 60, 6 that rotate in conjunction with the rotation of these electric motors.
1 and 62, and each of these movable terminals has a contact that detects the open position at a phase of 180 degrees, a contact that detects the closed position, and a contact that detects an intermediate position other than these. ,
The current is maintained until switching from the open position or the closed position to the reverse position is completed. These movable terminals 55 and 56, 57 and 58, 59
and 60, 61 and 62 are motor circuits 5 and 60, 61 and 62, respectively.
1, 52, 53, and 54.

In addition, _{X 1 ,} X _{2 ,} X _{3 , X 4} , _{X 5} , X ₆ , X ₇ , X ₈ are relays, and the relay contacts
x ₇ , x ₈ and these relays X ₁ , X ₂ , X ₃ ,
Electric motor M ₁ by X ₄ , X ₅ , X ₆ , X ₇ , X ₈ ,
The rotation angles of the output shafts of M ₂ , M ₃ , and M ₄ are derived from each movable terminal of the motor circuits 51, 52, 53, and 54,
A detection device is constructed to detect which position the stopper 31 is at, among the stop position _P3 , the stop release position _P5 , or any other intermediate position where the stopper 31 is in an incompletely locked state.

In addition, _each relay that constitutes this detection device
The desired stopper 31 is at the stop position from the open/closed state of the relay contacts X ₂ , X ₃ , X ₄ , X ₅ , X ₆ , X ₇ , and X ₈
To detect if _there is _a disconnection _{in the} wiring to _each relay _{X 1 , X 2} , An abnormality detection circuit 63 is provided.

T ₁ and T ₂ are timer relays, each having relay contacts t ₁ and t ₂ , of which the timer relay T ₁ is energized when the abnormality detection circuit 63 is activated.

PL ₁ , PL ₂ , and PL ₃ are pilot lamps, and when the desired stopper 31 is at the regular stop position P ₃ and the stop release position P ₅ , that is, if we take a rear dump truck as an example, the rear left and right stoppers 31 is at the stop position _P3 and the front left and right stoppers 31 are at the stop open position _P5 , the pilot lamp _PL1 lights up, and similarly, if the desired stopper 31 is at the proper position in response to left dumping, the pilot lamp is turned on. If the desired stopper 31 is in the proper position corresponding to the right dump, the lamp PL ₂ will be moved to the pilot lamp.
It is designed to light up each PL ₃ .

As mentioned above, 23 and 24 are, respectively,
Solenoid and alarm buzzer.

Next, the operation of the above embodiment will be explained.
Motor circuits 51, 52, 53, 54 shown in FIG.
is the rear dump state, specifically, the movable terminals 55 and 56, 59 and 60 of the electric motors _M1 and _M3 constituting the hinge switching actuating device 33 are in the open position (stopper 3
1 is in the open stop position P ₅ ), while the movable terminals 57 and 58 and 61 and 62 of the electric motor M ₂
is in the closed position (stopper 31 is in stop position P ₃ ).

Here, when the engine key switch SW ₁ is turned on by inserting the engine key, the power supply relay XR is energized and the normally open contact (hereinafter referred to as the A contact) XR is closed, so that the power supply voltage acts on the control system.

If the cargo box 1 is not on the chassis 4, the cargo box 1 is not in the running position, so the reed switch 9 is opened and the dump pushbuttons PB ₁ , PB ₂ , PB ₃ are opened.
Unable to operate the pilot lamp PL ₁ ,
PL ₂ and PL ₃ also do not light up. Therefore, the tilting operation of the cargo box 1 becomes impossible.

On the other hand, if the cargo box 1 is on the chassis 4, the cargo box 1
is in the running position, the reed switch 9 is operated to close, and the cargo box tilting operation lever 12 is in the cargo box prone position.
_P1 , and the limit switch 18 is also closed.

Next, when push button switch PB1 for rear dump is pressed, relay _R1 is energized, and its a contact _R1
is closed. As a result, the front left and right stoppers 31
is the stop release position _P5 , so
Relays X ₁ , X ₄ , and X ₈ that constitute the above-mentioned detection device are in a demagnetized state, and relays X ₂ , X ₃ , X ₆ , and X ₇ are in an energized state, and are normally closed contacts (hereinafter referred to as b contacts).
Pilot lamp PL ₁ lights up to indicate that rear dumping is possible via x ₄ , x ₅ , x ₁ , and x ₈ .

After that, when the cargo box tilting operation lever 12 is operated to extend the dump cylinder (not shown), the front left and right hooks 6, 6 are subjected to a tensile force on the spring (not shown) as the hinge shafts 3, 3 move upward. , and the hinge shafts 3 are unlocked, so that the cargo box 1 is tilted rearward.

On the other hand, when returning the cargo box 1 from the tilted state, the cargo box tilting operation lever 7 is operated in the opposite direction to retract the dump cylinder and the cargo box is laid down. 3, 3 are in contact,
The hooks 6, 6 are rotated against the tensile force of the spring, and the hooks 6, 6 and the hinge shafts 3, 3 are brought into engagement, resulting in a running posture that allows safe running.

In addition, when dumping to the left, press the push button switch PB ₂ for left dump, and relay R ₂ will be activated.
is excited, and its a contact _r2 is closed. As a result, from the state shown in FIG.
4. Movable terminals 55, 56, and 61 that interlock with each other
and 62, the movable terminals 55 and ₅₆ of the motor circuit ₅₁ change from the open position to the closed position, while the movable terminals 61 and 62 of the motor circuit 54 change from the closed position to the open position. Switch to position.
In this case, electric motors M ₂ and M ₃ have movable terminals 57
Since 58, 59, and 60 are open, they are not rotated.

Therefore, the hinge switching actuating device 33 described above
As a result of this operation, the left front and rear stoppers 31 are positioned at the stop position _P3 , and the right front and rear stoppers 31 are positioned at the stop open position ₅ , respectively. and,
The relays X ₂ , X ₄ , X ₅ , and X ₇ are demagnetized from the open/close states of the motor circuits 51 , 52 , 53 , and 54 , and the pilot lamp is activated via their B contacts x ₂ , x ₄ , x ₅ , and x ₇ .
PL ₂ lights up to indicate that a left dump is possible.

Next, when the cargo box tilting operation lever 12 is operated, the dump cylinder (not shown) is extended, and the cargo box 1 is
tilts to the left.

When the unloading of the cargo is completed, the cargo box tilting operation lever 12 may be operated in the opposite direction to return the cargo box 1 to the running state.

Similarly, when performing a right dump after a left dump, press the right dump pushbutton switch.
If you press PB ₃ , each motor circuit 51, 52, 5
At 3 and 54, a switching operation is performed, and only the hinge shaft 3 at a predetermined location can be released, and accordingly, the pilot lamp PL ₃ lights up, indicating that right dumping is possible, and tilting operation is possible. Become.

By the way, when dumping is selected in any direction, if the front left stopper 31 is located between the stop position _P3 and the stop release position _P5 , the movable terminals 55 and 56 of the motor circuit 51 is in an intermediate position other than the open position and the closed position, relays X ₁ and X ₂ are energized simultaneously, and their a contacts x ₁ ,
An abnormal state is detected by the abnormality detection circuit 63 via _x2 , and the timer relay _T1 is energized. and,
If this abnormal condition continues for more than 2 seconds, the a contact t ₁
As a result, the alarm buzzer 43 sounds to notify the operator, and the solenoid 23 is energized, which causes the rod 24 to be pulled, the lock lever 20 to rotate clockwise, and the cargo box tilting operation lever to be closed. 1
2 and disables the tilting of cargo box 1 (3rd
(See the solid line in the figure).

Further, when the a contact t ₁ of the timer relay T ₁ remains closed for 2 seconds or more, the timer relay T ₂ is energized, the b contact t ₂ is opened, and the solenoid 23 is deenergized.

In this case, once the lock lever 20 is locked, the spring 26 is at a dead point beyond the pivot 19, so unless the operator pushes the release lever 64 to release the lock,
The locked state of the cargo box tilting operation lever 12 continues.

In addition, in the above abnormal condition, if a foreign object is caught in the stopper 31 in the stop release direction, press the reverse switch PB ₅ to energize the relays R ₄ and R ₅ , and also press the specified dump push button. When the buttons PB ₁ , PB ₂ , PB ₃ are pressed, a current flows through the hinge switching actuating device 33 in the reverse direction and the rotation is reversed, so the stopper 31 rotates and the foreign object can be removed.

In this way, since the dumping direction can be controlled electrically, switching the dumping direction becomes easy and accurate, and the dumping direction switching lever that was conventionally installed in the operator's cab can be omitted. The space inside the driver's cabin becomes larger, improving comfort.

In addition, pushbutton PB ₄ is attached to each pilot lamp.
This is to check whether PL ₁ , PL ₂ , and PL ₃ are operating normally.

In the above embodiment, the dump operation is performed only when the reed switch 9, which detects whether the cargo box is in the traveling position, and the limit switch 18, which detects the operating state of the cargo box tilting operation lever 12, are both in the closed state. I'm trying to do it.

(Effects of the Invention) As described above, the present invention disables the operation of the selection switch when the cargo box detection means detects that the cargo box is not in the completely laid down position.
When the detection device detects that the hinge corresponding to the tilting direction selected by the selection switch is in an incompletely locked state, it activates the lashing means to disable the tilting operation of the cargo box. tilting work can be performed safely.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, and FIG. 1 is a perspective view showing the overall configuration of a three-turn dump truck, FIG. 2 is an explanatory diagram of the cargo box detection means, and FIG. 3 is an illustration of the state near the cargo box tilting operation lever. FIG. 4 is an explanatory diagram showing the structure of the hinge, FIG. 5 is a front view of the operation panel, FIG. 6 is an electric circuit diagram of the control system, and FIG. 7 is an explanatory diagram of the positional relationship of the electric motor. . 1... Packing box, 3... Hinge shaft, 4... Car number, 5... Shaft receiving member, 6... Hook, 9...
... Reed switch, 12 ... Carton tilting operation lever, 20 ... Lock lever, 23 ... Solenoid, 31 ... Stopper, 33 ... Hinge switching actuator, PB ₁ , PB ₂ , PB ₃ ... Dump push button ,
X ₁ ~ X ₈ ...Relay.

Claims (1)

[Claims] 1 Front, rear, left and right sides of either the chassis or the bottom of the cargo box 4
A hinge is constructed by providing a hinge shaft at one location, and a shaft receiving member, a hook, etc. corresponding to the hinge shaft at four locations on the other front, rear, left, and right, respectively, and a cargo box tilting operation lever controls the tilting operation of the cargo box. In the three-turn dump truck, the cargo box detection means is interposed between the chassis and the bottom of the cargo box and detects whether the cargo box is in a completely laid down position, and the hinge is set in a locked state and a released state. A hinge switching actuating device that selectively operates, a selection switch that actuates the hinge switching actuating device corresponding to each tilting direction, and a fully locked state, a completely released state, and an incompletely locked state of the hinge switching actuating device. and a lashing means for securing the cargo box tilting operation lever to the cargo box lying position, and the cargo box detecting means detects that the cargo box is not in the completely fallen position. When the selection switch is disabled,
When the detection device detects that the hinge corresponding to the tilting direction selected by the selection switch is in an incompletely locked state, the lashing means is activated to disable the cargo box from tilting. Hinge operation safety device for three-turn dump trucks.