JPS6220739A - Cargo table attitude controller for transporter - Google Patents

Abstract

PURPOSE:To facilitate uniform spray work of loaded sand and the like by detecting a main frame, an upper frame, a sub-frame and a cargo table through sensors and performing position control then vibrating the cargo table up/down within a predetermined angular range. CONSTITUTION:The front end of a sub-frame 30 is pivoted to the front end of a main frame 10 between the main frame 10 and a cargo table 20 to make the rear section rotatable up/down against the main frame 10. The rear end of the cargo table 20 is pivoted to the rear end of the sub-frame 30 to make the front section rotatable up/down against the main frame 10. The rotary angle of the sub-frame 30 against the main frame 10, the rotary angle of on upper frame 40 against the sub-frame 30 and the absolute angle of the cargo table 20 against the horizontal surface are detected through sensors then on the basis of detected angles, the cargo table 20 is automatically controlled to vibrate up/down within predetermined angular range. Consequently, sand loaded on the cargo table 20 can be sprayed uniformly onto the ground face while traveling slowly.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention has a so-called dump function that is configured so that a loading platform can be tilted in the longitudinal direction with respect to a main frame equipped with traveling devices such as crawlers and wheels. The present invention relates to a loading platform posture control device for a transport vehicle.

[Prior art]

Transport vehicles equipped with platforms for transporting various heavy objects, such as agricultural and forestry transport vehicles used for transporting seedlings, fertilizers, harvested products, and shiitake mushrooms, are equipped with crawlers, wheels, etc. The so-called dump function allows the cargo loaded on the platform to fall from the rear of the platform by tilting the entire platform by lifting and rotating the front part of the platform relative to the main frame equipped with the traveling device. generally have.

[Problem that the invention seeks to solve]

By the way, in transportation vehicles for agriculture and forestry, powder-like objects loaded on the loading platform, such as earth, sand, fertilizer, and corroded materials, are transported over a wide area of the ground surface by moving the vehicle slowly and tilting the loading platform. It requires gradual dropping and dispersion. During such work, the carrier vehicle is moved slowly and the loading platform is finely vibrated to cause the soil, etc. loaded on the loading platform to fall in appropriate amounts from the loading platform.
In conventional transport vehicles, fine vibrations of the loading platform are controlled by an operator repeatedly manually operating the lift lever of the loading platform. Therefore, the operation is complicated, and the loading platform is vibrated excessively, making it impossible to uniformly spread the earth and sand loaded on the loading platform.

[Means for solving problems]

The present invention has been made in view of the above circumstances,
A sub-frame is provided between the main frame on the main body side and the loading platform,
For example, the front end of the sub-frame is pivoted near the front end of the main frame so that its rear part can move up and down relative to the main frame, and the rear part of the cargo platform is pivoted to the rear end of this sub-frame. The front part is configured to be movable up and down with respect to the sub frame, in other words, with respect to the main frame, and includes a first sensor for detecting a rotation angle of the sub frame with respect to the main frame, and an upper part with respect to the sub frame. Equipped with a second sensor for detecting the rotation angle of the frame and a third sensor for detecting the absolute angle of the loading platform with respect to the horizontal plane, the loading platform can be moved to a predetermined position based on the detection results of each of these sensors. It is an object of the present invention to provide a loading platform posture control device for a transport vehicle that solves the above-mentioned problems by automatically controlling the vehicle to bounce and vibrate up and down within an angular range.

The present invention provides a loading platform posture control device for a transport vehicle, which controls the posture of the loading platform by rotating the loading platform in the front and rear directions with respect to the main frame equipped with a traveling device. A sensor for detecting the rotation angle is provided, and an instruction to vibrate the loading platform up and down is given, so that according to the detection result of the sensor,
Only when the upper frame is rotated by a predetermined angle or more in a direction away from the main frame, the upper frame is moved between the angular position at the time the instruction was given and a predetermined angular position on the main frame side. It is characterized by being made to repeatedly move up and down between the two directions.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below based on drawings showing embodiments thereof.

FIG. 1 is a schematic perspective view of a transport vehicle equipped with a loading platform attitude control device according to the present invention, seen from the rear right side, FIG. 2 is a plan view showing the structure of the frame of the loading platform portion, and FIG. Figure I
It is a side sectional view seen in the direction of arrow -1.

In the figure, lO is the main frame of the transport vehicle, which is mounted on a chassis 12 to which left and right running rollers 11.11 are attached. The front side of this main frame IO is a roller 11 that runs.
The driver's seat 1 and the power section 14 are mounted and equipped above this extended portion.

A loading platform 2o is provided above the rear part of the main frame 10 so that it can be tilted (dumped) and raised and lowered in the front and rear direction. Sub-frame 3 in the near part
The sub frame 3 is rotatable in the vertical direction with respect to 0.
0 is attached to the main frame 1O at a portion near its front end so as to be freely rotatable in the vertical direction. By adopting such a configuration, the sub frame 30 rotates in the vertical direction with respect to the main frame IO with its front part as the center of rotation, and the upper frame 40 rotates with respect to the sub frame 30.
The loading platform 20 is configured to be able to tilt and move up and down both forward and backward with respect to the main frame 10 by vertically rotating around its rear part.

Incidentally, here, the tilting of the loading platform 200 in the front-rear direction refers to the rotational movement of the loading platform 20 with respect to the main body of the transport vehicle, with one of its front and rear ends as the center of rotation, and rising and lowering refers to the movement between the main body of the transport vehicle and the transport platform. This means that the loading platform 20 moves up and down with respect to the carrier body while maintaining the parallel state with the loading platform 20. In addition, there are two ways to tilt the loading platform 20: a forward raising direction in which the front end portion is rotated in a rising direction with the rear end portion of the loading platform 20 as the center of rotation relative to the transport vehicle body; There is a front-lowering method in which the rear end is rotated upward with the center of rotation at .

First, the main frame 10 has left and right running rollers 11°11.
Chassis 1 that supports the rotating shafts of the drive wheels, guide wheels, etc.
2 left and right shear 9 members 127! , 12r, and left and right main frame members 101 and 1Or are attached to the upper sides of the main frames 101 and 12r, respectively. These left and right main frame members 10j? , left and right brackets 161 are located slightly outside the rear part of the driver's seat 1 of the driver's seat 1 with their upper portions protruding upwards from each of the left and right main frame members 10Jfor.
, 16r are installed. A rotating shaft 17 is rotatably inserted between the left and right brackets) 16C16r, and the left and right brackets t-1 of this rotating shaft 17
Portions near the front ends of left and right sub-frame members 301.30r constituting the sub-frame 30 are fixed to the portion between 61 and 16r, respectively.

Also, the left and right brackets 161 and 16 of the main frame 10
Left and right main frame members 101°1 from slightly behind r
A square pipe beam 18 is fixed between 0r, and left and right sub-frame members 30 are located approximately in the middle of the sub-frame 30 and are located behind the fixed position of the beam 18.
j! , 30r is also fixed with a square pipe beam 31. A hydraulic cylinder 32 is supported by a trunnion at a position approximately in the center of the beam 17 in the left-right direction, and the hydraulic cylinder 32 moves the loading platform 20 forward and downward by the advancement of its piston rod 32R. The end is pivotally supported by a square pipe beam 31 fixed to the side of the sub frame 30. Therefore, by supplying and discharging pressure oil to the hydraulic cylinder 32, the sub frame 30 can move the part near its front end. The main frame 10 is rotated at a position slightly rearward of the driver's seat 1 as a center of rotation. Note that the rotation angle of the sub frame 30 with respect to the main frame 10 is in the range of 0° to 115° (when the piston rod 32R advances, the loading platform 20 tilts forward and downward).

The right bracket 16r attached to the right main frame member 10r is equipped with a front position sensor 51 using a potentiometer, and the detected value FO is the rotation angle of the rotation bracket 17 with respect to the right bracket 16r. By detecting , one angle of rotation of the sub frame 30 relative to the main frame 10 is represented.

At the rear end of the sub frame 30, left and right sub frame members 30
Left and right brackets 33j are placed on the outside of each of e and 30r! , 33r are fixed at the front upper part of each.

A rotation shaft 34 is rotatably inserted into a portion of each of the left and right brackets 33j1, 33r that protrudes rearward from the sub-frame 30. On the other hand, left and right brackets 411.41r are provided on the outside of a portion near the rear end of each of the left and right upper frame members 401.4Or constituting the upper frame 40, and are attached so as to protrude downward.
Left and right brackets 411.41r fixed to these left and right upper frame members 401°4Or are fixed to the above-mentioned rotation shaft 34.

In addition, the left and right brackets 331°33 of the sub frame 30
A square pipe beam 35 is fixed between the lower front end portions of r, while the left and right upper frame members are located approximately in the middle of the upper frame 40 and at approximately the same position as the beam 31 is fixed. Square pipe beam material 4 between 40j' and 40r
2 is fixed. At a position approximately in the center of the beam 35 in the left-right direction is a hydraulic cylinder 4 for raising the front, which raises the loading platform 20 forward by advancing its piston rod 43R.
3 is supported by a trunnion, and the rod end of a piston rod 43R of this hydraulic cylinder 43 is pivotally supported by a beam member 42 fixed to the upper frame 40 side. Therefore, by supplying and discharging pressure oil to and from the hydraulic cylinder 43, the upper frame 4° is rotated with a portion near its rear end as the rotation center at the position of the rear end of the sub frame 3o. In addition,
The rotation angle of the upper frame 40 with respect to the sub frame 3o is 0.
It is in the range of +60° (the piston rod 43R advances and the loading platform 20 rotates forward and upward).

Note that the right side bracket 33j+ attached to the right side sub frame member 30r is equipped with a rear position sensor 5 using a potentiometer, similar to the front position sensor 51 described above, and its detected value 1
? 0 represents the relative rotation angle of the upper frame 40 with respect to the sub-frame 3o by detecting the rotation angle of the rotation shaft 34 with respect to the right bracket 33r.

Further, two frame members 451.45r in the front and back direction are further outside each of the left and right upper frame members 401.4Or to which the above-mentioned beam 42 and left and right brackets 41/, 41r are attached to the upper frame 4o. , 46
1°46r, respectively, and these six longitudinal upper frame members 411.41r, 45
12゜45r, 461, 46r are upper frame 40
The beams 47b and 47f forming the front and rear end beams are assembled into a frame shape.

The loading platform 20 is placed and fixed on the upper surface of this frame-shaped upper frame 40.

In addition, a loading platform sensor 53 for detecting the absolute inclination angle of the upper frame 40, in other words, of the loading platform 20 with respect to the horizontal plane, is provided on a suitable member of the upper frame 40 at approximately the center in the front-rear direction. The detected value NO represents the absolute inclination angle of the loading platform 20 with respect to the horizontal plane, regardless of the inclination state of the main frame 10, the expansion/contraction state of the hydraulic cylinders 32, 43, etc.

Therefore, when the piston rod 32R of the hydraulic cylinder 32 for forward lowering moves forward, the loading platform 20 rotates around its front end in a direction in which the rear end rises, and becomes tilted forward. As the piston loft 43R of the raising hydraulic cylinder 43 advances, the front end rotates in the upward direction about the rear end, resulting in a forward-raising tilted state.

Furthermore, if both piston rods 32R and 43R advance or enter by the same amount (actually, alternately as described later) from a state in which the loading platform 20 is parallel to the transportation vehicle main body, the loading platform 20 is parallel to the transportation vehicle main body. Rise or descend while remaining parallel to the

FIG. 4 is a schematic diagram showing the postures that the loading platform 20 can take,
(al means that the main frame IO and the sub frame 3o are parallel (detection value FO of the front position sensor 51 - 0°), and the sub frame 30 and the upper frame 40 are parallel (
The case where the detected value of the rear position sensor 52 is RO-0°) is shown. (in Fig. 4) is the case where the upper frame 40 rotates to its limit in the direction away from the sub frame 30 from the state (al) (RO-+60', FO-0°
) is shown. FIG. 4(c) shows the case where the sub frame 30 further rotates to its limit in the direction away from the main frame 10 from the state of bl (1?o=60°).

FO--15°), and in this case, the angle of the loading platform 2o with respect to the horizontal plane, that is, the detected value NO of the loading platform sensor 53
becomes +45°. Fig. 4 1d) shows the case where the upper frame 40 is rotated from the state of 10) to its limit in the direction approaching the sub-frame 30 and the two are made parallel (RO
-0', FO--15°), and in this case, the angle of the loading platform 20 with respect to the horizontal plane, that is, the loading platform sensor 53
The detected value NO is -15°. Note that this fourth If
If the sub frame 30 is further rotated in the direction approaching the main frame 10 from the state of dl so that they are parallel, the state of the same (a) is restored. Fig. 4(e) shows the state of the same (al) From there, the upper frame 40 is rotated with respect to the sub-frame 30, and the sub-frame 30 is rotated with respect to the main frame 10 by approximately equal angles alternately, and the upper frame 40, that is, the loading platform 2 is rotated.
0 is raised to its upper limit while maintaining a state parallel to the main frame 10 (RO-15°, FO--
15°).

As shown in FIG. 1, the driver's seat 1 is equipped with a power section 14 equipped with an engine, a transmission, etc. on the left side, and a control circuit for the device of the present invention (see FIG. 7) etc. is installed in the center part. There is a control console in which a control box 2, a moving latch lever 3, etc. are arranged in the front-rear direction, and a seat 5 for the operator, a control lever 41.4r, etc. are provided on the right side. The clutch lever 3 is equipped with a clutch sensor 54 (see FIG. 7) that detects the operation of the clutch lever 3, in other words, the change from a running state to a stopped state or from a stopped state to a running state. ing.

By the way, on the surface of the control box 2, there is provided an operation panel 6 for the apparatus of the present invention as shown in FIG.

Mode switches 61 arranged on this operation panel 6
, loading platform switch 62, lift switch 63, cylinder speed changeover switch 64, and vibration switch 6
Let me briefly explain the function of 5.

First, the mode switch 61 is a three-position selectable type, and three modes can be selected: manual mode, automatic mode, and parallel mode. When the manual mode is selected by the mode switch 61, the operator can manually control the inclination of the loading platform 2o by operating the loading platform switch 62, and vibrate the loading platform 2o by turning on the vibration switch 65. It is also possible to do so. When the automatic mode is selected, automatic control is performed to maintain the loading platform 20 horizontally regardless of the inclination of the carrier body, but priority is given to controlling the inclination of the loading platform 20 by manual operation of the loading platform switch 62. Further, when the tilt control of the loading platform 20 by the loading platform switch 62 is stopped, the automatic mode is immediately returned. If parallel mode is selected, loading platform 2
0 and the transport vehicle body, specifically, the upper frame 40 and the sub-frame 30 are parallel (detected value RO-0° of the rear position sensor 52), and the sub-frame 30 and the main frame 10 are parallel (the front position sensor 51 Detected value FO-0°
), and the loading platform 20 becomes parallel to the carrier body at the position closest to the carrier body (the state shown in Fig. 4 1a)), and
In this state, by operating the lift switch 63, the loading platform 20 can be raised and lowered (lifted up and lifted down) while the parallel relationship between the loading platform 20 and the transport vehicle body is maintained.

The loading platform switch 62 is a switch that tilts (dumps) the loading platform 20, and when operated to the "up" position, the loading platform 20 tilts (dumps).
is in the forward-raised state (in the order of Fig. 4 (a) - mountain 1 - (e)), and when it is in the "down" position, the loading platform 2o is in the forward-lowered state (in the order of Fig. 4 (CI-(d) - (al)). Note that when this loading platform switch 62 is operated, priority is given to manual control for tilting the loading platform 20 by operating the loading platform switch 62, regardless of the mode selected by the mode switch 61 described above.

The lift switch 63 is a polynym type switch,
The loading platform 20 is raised and lowered to a height position corresponding to the rotational position while maintaining a parallel relationship with the carrier body (as shown in FIGS. 4(a) to 4(e)). The parallel mode is selected by the mode switch 61 and the loading platform 20
is at the lowest position relative to the transport vehicle body! ! ! (The sub-frame 3 of the upper frame 40 as shown in FIG. 4(a)
Rotation angle relative to 0 and main frame 10 of rigid frame 30
The operation is effective only when the rotation angles for both are 0''') and are operated from "low" to "high".

The cylinder speed changeover switch 64 is a mode switch.
This is a switch that selects the speed of tilting or raising and lowering the loading platform 20 (specifically, the rod driving speed of the hydraulic cylinder 32, 43) when the automatic mode is selected with the switch 61, and it can be adjusted relatively quickly in both directions. piston rod 32
Three speeds can be selected: "fast" in which R and 43R are driven, "slow" in which both piston rods 32R and 43R are driven relatively slowly, and "medium" between the two. As will be described later, the speed is automatically selected as "medium" in the manual mode, "medium" or "slow" in the parallel mode, and "slow" when the lift switch 63 is used to raise and lower the loading platform 20. In addition, immediately before the rotation of the sub frame 30 or the upper frame 40 is stopped, the cylinder speed is controlled relatively slowly, as will be described later.

The vibration silencing switch 65 is used to control the vibration of the loading platform 20, that is, the condition in which the loading platform 20 is tilted upward (see FIG. 4).
This is a control in which the loading platform 20 is rotated vertically by several degrees (5 degrees in this embodiment) in a state intermediate between a) and false),
For example, this is carried out when it is necessary to drop earth and sand loaded on the loading platform 20 while the main body is running.

FIG. 6 is a hydraulic circuit diagram of the main parts of a transport vehicle equipped with the device of the present invention.

In the figure, 32 and 43 are the aforementioned hydraulic cylinders, both of which are 4
Pressure oil is supplied and discharged by a boat 3-position switching type electromagnetic directional control valve V2. V
3 are the solenoids Su2. When Su3 is excited, the switching position Tu) is reached, and pressure oil is supplied to the oil chamber on the advancing side, which causes the piston rods 32R, 4
3R advances and the sub frame 30 separates from the main frame lO (detection value F of the front positive sensor 51)
O is 0° - 15°, the loading platform 20 is lowered forward), or the direction in which the upper frame 40 is separated from the rigid frame 3o (the detected value RQ of the rear position sensor 52 is 0° → +60°
, the loading platform 20 is rotated upward to the front-up position) and the inclination becomes large, and conversely, the solenoid Sd2. When Sd3 is energized, the switching position (d) is reached, and pressure oil is supplied to the oil chamber on the retracting and retracting side, which causes the piston rod 32R to
, 43R retract and the sub frame 30 approaches the main frame 10 (the detection value FO of the front position sensor 51 is -15° → 0°, the loading platform 20 is raised forward), or the upper frame 40 moves toward the sub frame 10. Direction approaching 30 (
The detection value RO of the rear position sensor 52 is +60' -
0', the loading platform 20 is rotated downward (frontward downward) and the inclination becomes small, and both solenoids Su2. Sd2 or Su3. If both Sd3 are not excited, the neutral position (
nl, the pressure oil in the oil chambers of both hydraulic cylinders 32, 43 is sealed, and both piston rods 32R, 43R are locked in their current positions.

In addition, both electromagnetic directional control valves V2. V3 is not directly supplied with pressure oil from the hydraulic pump P, but another electromagnetic directional control valve v1 is interposed between the two and the hydraulic pump P, and both electromagnetic directional control valves V2. Pressure oil supply to V3 is being switched. This switching electromagnetic directional control valve v
1 is a 4-port 2-position switching type, and its solenoid S
1 is demagnetized. In this case, the pressure oil discharged from the hydraulic pump P is supplied to the electromagnetic directional control valve v3 interposed between the forward lifting hydraulic cylinder 43 and the solenoid S.
1 is excited, the pressure oil discharged from the hydraulic pump P is supplied to the electromagnetic directional control valve v2 interposed between the hydraulic cylinder 32 for forward lowering.

Double electromagnetic directional control valve V2. Neutral position i for each V3
Even though there is n+, the electromagnetic directional control valve ν1
Both electromagnetic directional control valves v2. The reason why pressure oil is supplied to only one of the solenoid directional control valves V3 is that when the solenoid directional control valve v1 is not used, both the solenoid directional control valves V2. V
3 each solenoid Su2. Su3. Sd2. Sd
In order to control 3, 4 systems of signals are required. However, in the case of the configuration shown in FIG. 6, both electromagnetic directional control valves V2. Solenoids Su2 and Su3 of V3 are controlled by one system of signals, and solenoids Sd2 and Sd3 of V3 are controlled by one system of signals, and this and solenoid S of electromagnetic directional control valve v1 are controlled by one system of signals.
This is because by combining the signals for controlling the first and second hydraulic cylinders 32 and 43, it becomes possible to control both hydraulic cylinders 32 and 43 with three systems of signals.

FIG. 7 is a block diagram of the control circuit of the apparatus of the present invention.

71 in the diagram is C20, RO? It is a control unit using RAM, etc., and is an input port at ~ to which analog signals are input.
a4, input ports d to which digital signals are input, ~d8
and output ports) b+ to b3 from which digital signals are output. Note that aQ is a power supply terminal, and a power supply voltage is supplied from the battery 70 via the key switch 75.

The above-mentioned front position sensor 5 is connected to the input port a1.
1, that is, a sensor 5 that detects the relative inclination angle of the rigid frame 30 with respect to the main frame 10 (the forward lowering angle of the loading platform 20);
1 output (detected value FO) is given to a2, and the above-mentioned rear position sensor 52, that is, the sensor 52 that detects the relative inclination angle of the upper frame 40 with respect to the sub frame 30 (the forward lifting angle of the loading platform 20). The output (detected value RO) is given to a3, and the output (NO) of the aforementioned loading platform sensor 53 that detects the absolute angle of the loading platform 20 with respect to the horizontal plane is given as an analog electric signal. The detection range of each of these sensors 51 to 53 will be explained below.
For both sensors, the detected value when the loading platform 20 is in the forward-up position is +, and the detected value when the loading platform 20 is in the forward-down position is -. Therefore,
The detection range of the front position sensor 51 is ±06 to -
15°, detection range of rear position sensor 52 is ±0°
~+60°, and the detection range of the loading platform sensor 53 is ±15°.

A clutch sensor 54 is connected to the input port d1. This clutch sensor 54 inputs a high-level signal to the input port d when the clutch lever 3 comes into contact with it each time the clutch lever 3 is operated, in other words, each time the transport vehicle starts or stops. This prohibits operation immediately after the transport vehicle has started or stopped. In addition,
As the clutch sensor 54, for example, an optical sensor such as a photo ink clutch may be used.

(in capo) d2. ct are connected to two contacts 61M and 61A of the mode switch 61 of the operation panel 6, respectively. That is, when the manual mode is selected by the mode switch 61, the contact 61M is closed and a high level signal is input to the input capo-1-d2, and when the automatic mode is selected, the contact 61A is closed. When the parallel mode is selected, both contacts 61M and 61A are closed and a high level signal is input to the input port d2. d3, the control unit 74 recognizes the selected mode.

Two contacts 62u and 62d of the loading platform switch 62 of the operation panel 6 described above are connected to the input ports a, aS, respectively. That is, when the loading platform switch 62 is operated to the "up" side, the contact 62u is closed and a high level signal is input to the input port (di), and when it is operated to the "down" side, the contact 62d is closed. When the circuit is closed and a signal at the noise level is input to the input port ds, the control section 74 recognizes an instruction to raise or lower the loading platform 20.

Input capo) aS has a lift switch 63 on the operation panel 6.
An analog voltage signal representing the lift position (elevating height) of the loading platform 20 is provided.

Two contacts 64h and 64J of the cylinder speed changeover switch 64 of the operation panel 6 are connected to the input ports d6 and di, respectively. That is, as described above, when the automatic mode is selected by the mode switch 61, the operating speed of the hydraulic cylinder 43.32 for forward raising or lowering can be set by the cylinder speed changeover switch 64. As a result, when "speed" is selected, the contact 64h is closed and a high level signal is input.
s and if "slow" is selected, contact 64I
t is closed, a high level signal is input to the input port d7, and if "middle J" is selected, both contacts 64h and 6i
are both closed and a high level signal is re-input to port d6+
The control unit 74 recognizes the selected cylinder speed by inputting it to d7.

A vibration silencing switch 65 of the operation panel 6 is connected to the input port de, and when the vibration silencing switch 65 is turned on, a high-level signal is input to the input port aB to instruct vibration control of the loading platform 20. The control unit 74 recognizes this.

On the other hand, a switching transistor 72 in which a solenoid S1 of the electromagnetic directional control valve v1 described above is interposed between the battery 70 and the output port b is connected. Therefore, high level 1 from output port b
When the signal is output, the solenoid S1 is energized, and thereby the pressure oil discharged from the hydraulic pump P is sent to the electromagnetic directional control valve v2 connected to the front lowering hydraulic cylinder 32. Conversely, when the signal output from the output port b+ is at a low level, the solenoid S1 is demagnetized, and the pressure oil discharged from the hydraulic pump P is thereby directed in the electromagnetic direction connected to the forward lifting hydraulic cylinder 43. It is fed to the control valve v3 side.

The above-mentioned two electromagnetic directional control valves V2. Solenoid Su2 for V3's d-sode advance. A switching transistor 72 with Su3 interposed in parallel is connected. Therefore, output port b
When a high level signal is output from 2, both solenoids S
u2. Su3 is excited together. However, when the solenoid Sl' of the electromagnetic directional control valve Vl for hydraulic cylinder switching is not energized, only the energization of the solenoid Sa3 is actually effective, and conversely, when the solenoid S1 is energized, the solenoid Su2 Only the excitation of is effective.

The above-mentioned two electromagnetic directional control valves V2. V3 rod retraction solenoid Sd2. A switching transistor 73 with Sd3 interposed in parallel is connected. Therefore, output port b
When a high level signal is output from 3, both solenoids S
d2. Sd3 are both excited, but similarly to the above, the solenoid Sl of the electromagnetic directional control valve Vl for switching the hydraulic cylinder
When solenoid Sd3 is not excited, only the excitation of solenoid Sd3 is actually effective, and conversely, when solenoid S1 is excited, only #magnetism of solenoid Sd2 is effective.

The operation of the apparatus of the present invention configured as described above will be explained below.

FIG. 8 is a flowchart showing the main routine of the control processing contents of the control section 74, and an outline will first be explained according to the flowchart of FIG.

When the power is turned on, the control unit 74 first performs various initial settings or defines each input port and output port.
This initial setting includes, for example, each solenoid Su2 other than the hydraulic cylinder switching solenoid S1. Su3.
Sd2. One unit of on time T when exciting Sd3
On is set to 10m, and the actual excitation is performed by initializing the on time Ton to be 4 consecutive times ton (40ns), or by resetting all of the flags described below (・0).
This includes processing such as

Here, the solenoids Su other than the switching solenoid Sl
2. Sn2. Sd2. The drive control of Sd3 will be explained in accordance with the flowchart of FIG. 9 showing its contents.

Solenoid Su2. Sn2. Sd2. Excitation of Sd3 and the like is performed in units of on-time Ton (10 sa), and each time the on-time Ton elapses, interrupt processing is checked, etc.

And this is repeated 4 times, that is, the initial setting time to
When n(-TonX4) has elapsed, solenoid Su2. S
u3+Sd2. Sd3 etc. are demagnetized. After this, if the off time toff is set to 0, the next process is performed immediately (in most cases, the same solenoid 5 (12150
315d21Sd3 etc.) is performed for a time ton=TonX4, and the off time Loft is 0.
If not, check the interrupt processing, etc. until the time toff elapses, wait for the off time ton to elapse, and then perform the next process (in most cases, the same solenoid Su2. Sn2. Sd2. ' Process of exciting Sd3 etc. over time ton-TonX4) is performed.

Therefore, when the off time Loft is set to 0, solenoid Su2. Sn2. Sd2. When the excitation of Sd3 etc. is instructed, each of these solenoids is excited almost continuously, and the cylinder speed becomes the highest. In other words, when "speed" is selected by the cylinder speed changeover switch 64, the off time toff
is set to O. Conversely, when the off time toff is not 0, the solenoid Su2. Su3°Sd2.
When the excitation of Sd3 etc. is instructed, each solenoid will be intermittently excited, and the cylinder speed will change depending on the off time to
This is slower than when ff is 0. In other words, the greater the off time toff, the slower the cylinder speed. Specifically, when the cylinder speed "medium" is selected by the cylinder speed changeover switch 64, the off time toff is set to four times the on time Ton, and when the cylinder speed is selected "slow", the off time toff is set to four times the on time Ton. is the off time tof
f is set to 12 times the on-time Ton.

Therefore, solenoid Su2. Sn2. Sd2. S
d3 etc. are continuously excited when the cylinder speed is "fast", are intermittently excited by repeating excitation and demagnetization every 40 sa when the cylinder speed is "medium", and are excited intermittently when the cylinder speed is "slow". 40g
Excitation for 120 m and demagnetization for 120 m are repeated to intermittently excite.

When the initial settings as described above are completed, the control unit 74 checks the mode switch 61.
As a result of the check in step 1, if the automatic mode is selected, control is performed to maintain the loading platform 20 horizontally regardless of the inclination of the carrier body. That is, the control unit 74 checks the cylinder speed changeover switch 64 and sets the above-mentioned off time toff.
0 if the cylinder speed selected in is "speed"
In the case of "medium", the on-time Ton is 4 times, that is, 40
am, and in the case of "slow", it is set to 12 times the on time Ton, that is, 120 hours.

Next, the control unit 74 controls the detected value RO of the rear position sensor 52 which detects the relative inclination angle between the upper frame 40 to which the loading platform 20 is attached and the sub frame 30, and the detected value RO between the main frame 10 and the sub frame 30. The detection value FQ of the front position sensor 51, which detects the relative inclination angle between (RO≦0° means that the upper frame 40 and sub-frame 30 are parallel), or the detection value FO of the front position sensor 51 is FO≧0° (the front position sensor 51 Since the detection range of F is from 0° to -15°, F
O≧0° means that the sub frame 30 and the main frame lO are parallel) is automatically controlled so that the loading platform 20 is maintained parallel to the main body. Proceed to an automatic subroutine to do otherwise,
In other words, when the absolute values of both the detected values RO and FO of the rear position sensor 52 and the front position sensor 51 are larger than 0° (in the direction in which the upper frame 40 is separated from the sub frame 30, 30 are rotated in a direction away from the main frame IO), automatic control is not performed and the process returns to the step of checking the mode switch 61.

Therefore, in order to perform this automatic mode, it is necessary to manually set the rotation angle of either the upper frame 40 or the sub-frame 30 to Oo.

Now, if it is detected in the step of checking the mode switch 61 that the manual mode is selected, the control unit 74 checks the loading platform switch 62. Then, the loading platform switch 62 is set to "up" (or "down").
If the lift flag UD is set (υD-1), the manual lift subroutine (or manual lowering subroutine) is entered to move the loading platform 20 forward, that is, as shown in FIG. 4(a). The order of (b) - + (c) (also C, forward downwards, that is, Fig. 4 (c) - (d) - (al III))
After completing this subroutine, the lifting flag UD is reset ([0.0)] and the process returns to the step of checking the loading platform switch 62.

On the other hand, if the loading platform switch 62 is not operated in either "up" or "down" mode in the manual mode, the vibration switch 65 may be instructed to vibrate the loading platform 20, so the control unit 74 Check. That is, first, the control unit 74 checks the state of the pipe resilence flag V, which is set when vibration of the loading platform 20 is instructed, and if it is set (V-1), it immediately resets it (V-1). -0), the operation state of the mode switch 61 is checked, and then the process proceeds to a step of checking whether the pipe reciprocation switch 65 is turned on. This is done to give priority to the vibration operation of the loading platform 20 over the mode change by operating the mode switch 61. If the vibration switch 65 is not turned on, the process returns to the step of resetting the vibration run flag V and checking the mode switch 61, and the vibration switch 65 is turned on.
If it is turned on, the process proceeds to a vibration subroutine for controlling the vibration of the loading platform 20, and after the end of this subroutine, the process returns to the step of setting the vibration flag V and checking the loading platform switch 62.

Therefore, when in manual mode, the vibration switch 65
While the mode switch 61 is turned on, the mode switch 61 cannot be operated to switch to other automatic modes or parallel modes.

When the parallel mode is selected by the mode switch 61, the control unit 74 controls the upper frame 40 and the sub frame 30.
When the loading platform 20 is set parallel to the main body (Fig. 4 (al state)) with the rotation angles of both Oo, and in this state there is an instruction to raise the loading platform 20 (lift amplifier) by the lift switch 63. Then, the loading platform 20 is raised and lowered (as shown in FIG. 4 Cei).

First, the control unit 74 checks whether the lift switch 63 is in the off state. In order to prevent danger, load collapse, etc., the loading platform 20 is raised and lowered by setting the rotation angles of both the upper frame 40 and the sub-frame 30 to Oo so that the loading platform 20 is parallel to the main body (see Fig. 4). This is because the process is performed after the state a) is established.

If the lift switch 63 is off, the control unit 74 sets the rotation angles of both the upper frame 40 and the sub frame 30 to 0.
°, proceed to the parallel subroutine to make the loading platform 20 parallel to the main body, and after completing this subroutine, read the setting value of the lift switch 63 again, and then raise and lower the loading platform 20 in a state parallel to the main body. After the lift subroutine ends, the process returns to the step of checking the mode switch 61.

Next, automatic subroutines will be explained. As described above, this automatic subroutine is a subroutine for controlling the loading platform 2o so that it is always horizontal with respect to the main body, regardless of the inclination state of the main body, when the automatic mode is selected by the mode switch 61. be. FIG. 10 is a flowchart showing the contents of this automatic subroutine.

As described above, when the automatic mode is selected by the mode switch 61, the cylinder speed is set by the cylinder speed changeover switch 64, and the rear position sensor 52
Alternatively, the detected values RO and FO of either the front position sensor 51 are Oo, that is, the upper part 71/-m4 (L!:
If the III frame 30 or the sub frame 30 and the main frame IO are parallel, this automatic subroutine is executed.

First, the control unit 74 reads the detection value NO of the loading platform sensor 53, but if the clutch sensor 54 is on, that is, if the state of the transport vehicle changes from a running state to a stopped state or vice versa, Processing is not started until one second has passed after this clutch sensor 54 is turned off. Now, when the process is started by turning off the clutch sensor 54,
The control unit 74 performs control according to the detection value NO of the loading platform sensor 53. That is, when the detection value NO of the loading platform sensor 53 is in the range of ±1°, the loading platform 20 is horizontal, specifically, the main frame 10 and the sub frame 30 are parallel, and the secondary frame 30 and the upper frame 40 are parallel. is parallel (Fig. 4)
However, for example, the detected value NO of the loading platform sensor 53 is greater than +1° (the front of the loading platform 20 is higher than the rear, that is, the front is raised).
, and if the angle is greater than +4°, an automatic lowering subroutine is executed to automatically lower the front part of the loading platform 20 relatively quickly, and if the angle is greater than +1",
If the angle is 4° or less, a forward lowering speed limiting subroutine for lowering the front portion of the loading platform 20 relatively slowly is executed. Conversely, the detection value NO of the loading platform sensor 53 is smaller than 11° (the rear of the loading platform 20 is higher than the front, that is, the front is lowered)
, and if it is smaller than -4 degrees, an automatic raising subroutine is executed to automatically raise the front part of the loading platform 20 relatively quickly, and if it is smaller than -1 degrees, it is -4 degrees. If the temperature exceeds .degree., a forward raising speed limiting subroutine for relatively slowly raising the front portion of the loading platform 20 is executed.

FIG. 11 shows a flowchart of the automatic lowering subroutine, and FIG. 12 shows a flowchart of the automatic raising subroutine.

The automatic lowering routine is a process that is performed when the loading platform 20 is in a raised state with respect to a horizontal surface.

This automatic lowering subroutine starts by reading the detected values of the rear position sensor 52, and if the detected value RO of the rear position sensor 52 is not θ°,
That is, when the upper frame 40 is separated from the sub frame 30 in the forward upward direction, the solenoid Sd3 is energized and the piston rod 4 of the forward upward hydraulic cylinder 43 is activated.
3R is retracted and the upper frame 40 is rotated downward in the forward and downward direction with respect to the subframe 30, that is, in the direction in which it approaches the subframe 30, thereby bringing the two closer together, thereby moving the loading platform 20 in the forward and downward direction (more horizontally). (in the direction closer to). On the other hand, when the detected value RO of the rear position sensor 52 is 0°, the upper frame 40 as described above
Since it is impossible to control the solenoid 31. to rotate downward in the direction approaching the sub frame 30, the detected value FO of the front position sensor 51 is read, and if this is smaller than its rotation limit Oo, the solenoid 31. By energizing Su2 and advancing the piston loft 32R of the forward-lowering hydraulic cylinder 32, the sub frame 30 is rotated upward in the forward-down direction with respect to the main frame 10, and the two are separated, thereby moving the loading platform 20 forward. It rotates in the downward direction (toward the horizontal plane).

On the other hand, the automatic lift subroutine is a process that is performed when the loading platform 20 is in a forward downward position with respect to a horizontal plane. This automatic lift subroutine is started by first reading the detection value FO of the front position sensor 51, and the detection value FO of the front position sensor 51 is 0.
If not, that is, if the sub frame 30 is tilted forward and downward relative to the main frame 10, the loading platform 20 is tilted forward from the horizontal plane, and the detected value FO of the front position sensor 51 is -15 degrees, If the sub frame 30 is rotated further forward or downward relative to the main frame 10, there is a risk of the load collapsing, so no control is performed.However, the front position sensor 51
If the detected value FO is larger than 0° and 15° is not dripped, the solenoids S1 and Sd2 are energized and the piston loft 32R of the hydraulic cylinder 32 for forward lowering is retracted, thereby moving the sub frame 30 to the main frame. The loading platform 20 is rotated in the forward upward direction relative to the IO to bring the two closer together, and the loading platform 20 is rotated in the forward upward direction (to approach the horizontal plane). On the other hand, when the detected value FO of the front position sensor 51 is 0°, it is impossible to control the sub-frame 30 to approach the main frame IO as described above. This is +
If it is less than 30 degrees, the solenoid Su3 is energized to advance the piston rod 43R of the hydraulic cylinder 43 for forward lifting, and the upper frame 40 is rotated in the forward upward direction relative to the sub frame 30, thereby separating the two. This is to rotate the loading platform 20 in a forward upward direction (towards a horizontal plane). In addition, at this time, the rear position sensor 5
If the detected value RO of step 2 is greater than +30°, no control is performed because there is a risk of cargo collapse.

The forward raising speed limiting subroutine and the forward lowering speed limiting subroutine 1. When the loading platform 20 is tilted or raised or lowered, for example, the rotation limit of the rigid frame 30 to the main frame 10 m (detected value FO of the front position sensor 51) is used.
approaches 0° from a negative value) or upper frame 40
As the rotation speed toward the sub frame 30 approaches the limit (the detection value RO of the rear position sensor 52 approaches 0° from a positive value), the rotation speed (specifically, the hydraulic cylinder 3
2.43 (advancing/retracting speed of the piston lofts 32R, 43R) is performed relatively slowly, and the solenoid Su2. Sn2. Sd2
．． This is executed by increasing the off time toff during excitation of Sd3 and the like.

FIG. 13 is a flowchart showing the processing contents of the forward lowering speed limiting subroutine. In this subroutine, first, the state of the parallel flag sent in the parallel mode parallel subroutine to be described later is checked. Then, if the parallel flag is not set, the detection value NO of the loading platform sensor 53 is read, and if the parallel flag is set, the detection value RO of the rear position sensor 52 is read and this value is replaced with NO. 0 Next, check the cylinder speed changeover switch 64 and set the cylinder speed to "slow".
is selected, the off time toff is set to 12 times the on time Ton, and the cylinder speed is set to "medium".

When "speed" is selected, after setting the off time toff to four times the on time Ton, the detection value NO of the loading platform sensor 53 (or rear position sensor 52) is set.
, The above-mentioned automatic lowering subroutine continues until RO becomes 2 degrees or less when "slow" is selected as the cylinder speed, and until it reaches 3 degrees when "medium" or 1 "speed" is selected as the cylinder speed. Repeat the process.

In addition, when the cylinder speed is "R Medium" or "Speed", the off time t is set when the detected values No. and RO of the loading platform sensor 53 (or rear position sensor 52) are 3 degrees or less and up to 2 degrees, respectively.
Off is set to 12 times the on time Ton, resulting in a somewhat slow cylinder speed. Then, the detection values NO and RO of the loading platform sensor 53 (or rear position sensor 52) are 2.
When the cylinder speed is less than ', the off time Loff is set to 22 times the on time Ton, the cylinder speed is made relatively slow, and the automatic lowering subroutine is processed, regardless of the cylinder speed selection by the cylinder speed changeover switch 64.
The detection values NO and RO of the loading platform sensor 53 (or rear position sensor 52) are l.

The process ends when the number is below. Finally, if the parallel flag is set, the rear position sensor 52
NO is replaced as the detected value RO.

On the other hand, the flowchart shown in FIG. 14 shows the forward raising speed limiting subroutine, and this forward raising speed limiting subroutine is performed when the detected value NO of the loading platform sensor 53 (or rear position sensor 52) is the forward lowering speed mentioned above. In the limit subroutine, it approaches 0° from positive, whereas it approaches 0° from negative.
Except for approaching , the process is basically the same as the forward lowering speed limiting subroutine described above, so a description thereof will be omitted.

In this way, in the forward lowering speed limiting subroutine and the forward raising speed limiting subroutine, as the detection value NO of the loading platform sensor 53 approaches 0°, in other words, as the loading platform 20 becomes horizontal, each solenoid Su2. Sn2゜Sd2.
Off time toff with respect to on time Ton of Sd3 etc.
is set longer, the piston rods 32R, 43R of the hydraulic cylinders 32.43 are advanced and retracted more slowly, and therefore the loading platform 20 is rotated more slowly.

Next, control in manual mode will be explained.

If the manual mode is selected by the mode switch 61, the control unit 74 next checks the platform switch 62. At this time, if the loading platform switch 62 is operated to the "raise" side, the lifting flag UD is set and the manual lift subroutine is executed, whereby the lifting control of the loading platform 20 is performed and the loading platform switch 62 is set. If the operation is on the "down" side, the lift flag 110 is set and the manual lowering subroutine is processed, thereby controlling the lowering of the loading platform 20. After each subroutine is completed, the lift flag UD is set. will be reset.

FIG. 15 is a flowchart showing the processing contents of the manual ascending subroutine, and FIG. 16 is a flowchart showing the processing contents of the manual descending subroutine.

In the manual raising subroutine, the control unit 74 first reads the detected value RO of the rear position sensor 52, and this
In other words, the solenoid Su
3 excitation is performed. Thereafter, the control unit 74 reads the detected value FO of the front position sensor 51, and rotates the sub frame 30 upward and downward in the direction of moving away from the main frame 10 until it reaches -15°, which is the rotation limit. Naroma solenoid 51. Excite Su2.

In other words, when raising the loading platform 20 in manual mode, first raise the upper frame 40 to which the loading platform 20 is attached.
is rotated forward and upward to the rotation limit in the direction away from the sub frame 30 to an inclination angle of 60 degrees, and then the sub frame 30 is rotated in the direction away from the main frame IO to the rotation limit of -15 degrees. It is rotated forward and downward, and as a result, the loading platform is tilted at an angle of 45°.

On the other hand, in the manual lowering subroutine, the control unit 74 first reads the detection value RO of the rear position sensor 52, and waits until this value reaches 0°, that is, the upper frame 40 to which the cargo platform 20 is attached approaches the sub-frame 30. The solenoid Sd3 is rotated forward and downward in the direction shown in FIG. After that, the control unit 74 reads the detected value FO of the front position sensor 51, and until this becomes Oo, that is, the sub frame 30 is rotated forward and downward in the direction approaching the main frame 10, and both are parallel to each other. Energize solenoids SL and Sd2 until

In other words, when lowering the loading platform 20 in manual mode, first lower the upper frame 40 to which the loading platform 20 is attached.
is rotated in a forward downward direction until it approaches the sub frame 30 and becomes parallel to it, and then rotated in a forward upward direction until the sub frame 30, which has become parallel to the upper frame 40, approaches the main frame IO and becomes parallel to it. be done.

By the way, in the manual mode, by operating the vibration switch 65, it is possible to vibrate the loading platform 20, that is, to repeatedly move the loading platform 20 up and down. This operation is performed, for example, when scattering earth and sand placed on the loading platform 20 while moving the carrier vehicle slowly. The vibration subroutine processing when controlling the vibration of the loading platform 20 by the vibration switch 65 will be described below with reference to the flowchart shown in FIG. 17 showing its contents. In addition,
The vibration control of this loading platform 20 is carried out by a hydraulic cylinder 43 for raising the front.
This is executed by moving the upper frame 40 up and down with respect to the sub-frame 30.

First, the control unit 74 controls the detected value R of the rear position sensor 52.
O is read, and if this is less than +5°, the processing of this vibration subroutine is not performed. This means that the vibration of the loading platform 20 due to the vibration subroutine is
Since the operation is performed within a range of 5 degrees downward from the current position of 0, if the upper frame 40 has not been rotated by +5 degrees or more relative to the sub frame 30, the loading platform 20
This is because there is no room to move it up and down.

On the other hand, if the detection value FO of the rear position sensor 52 is 57 degrees or more, the vertical movement of the loading platform 20 is caused by the upper frame 40.
This is done within a range of 5° downward from +60°, which is the rotation limit with respect to the sub frame 30.

Now, the detected value RO of the rear position sensor 52 is +
If it is larger than 5° and smaller than +57°, the off time torf is first set to O, the solenoid Sd3 is energized, and the upper frame 40 is rotated forward and downward in the direction approaching the sub frame 30. Ru. During this time, the control unit 74 reads the detected value of the rear position sensor 52 and
1, and the solenoid Sd3 continues until the value RO-5, which is obtained by subtracting 5° from the detected value RO before excitation of the solenoid Sd3.
Continue excitation. In other words, the upper frame 40 has 5
° It is rotated forward and downward, that is, in a direction approaching the sub frame 30. However, the detection value R of the rear position sensor 52
1 becomes 0°, the solenoid Sd3 is demagnetized and the rotation of the loading platform 20 in the direction approaching the sub-frame 30 is stopped. Then, when the upper frame 40 to which the loading platform 20 is attached rotates downward toward the sub-frame 30 and approaches the sub-frame 30 by 5 degrees, the solenoid Sd3 is demagnetized, and then the solenoid Su3 is energized. This solenoid Su3
During the excitation, the control unit 74 reads the detected value of the rear position sensor 52 and sets it as R2. rear position sensor 52
The solenoid Su3 is excited, in other words, the upper frame 40 is rotated upward in the direction away from the sub-frame 30 until the detected value RO becomes equal to the detected value RO.

With the above control, the loading platform 20 is moved from the initial position to the 5th position.
This is one reciprocation between the position below, that is, 5 degrees close to the sub frame 30, and this control is repeated while the vibration switch 65 is operated.
vibration control is performed.

Next, control when the relative rotation angle between the upper frame 40 and the sub-frame 30 is +57° or more (however, +60° or less) will be described. In this case, first, the control unit 7
4 sets the off time toff to 0 and solenoid Sd3
is excited to rotate the upper frame 40 forward and downward in a direction approaching the sub-frame 30.

During this time, the control section 74 controls the rear position sensor 52.
Read the detected value and set it as R3, which is the solenoid Sd3.
Excitation of the solenoid Sd3 is continued until the value RO-5 obtained by subtracting 5 degrees from the detected value RO before excitation is reached. In other words,
The upper frame 40 is rotated downward by 5 degrees forward. Then, when the upper frame 40 to which the loading platform 20 is attached rotates downward toward the sub-frame 30 and approaches by 5 degrees, the control section 74 demagnetizes the solenoid Sd3 and then energizes the solenoid Su3. During the excitation of the solenoid Su3, the control unit 74 reads the detection value R4 of the rear position sensor 52, and the control unit 74 reads the detection value R4 of the rear position sensor 52, and the upper frame 40 rotates until the rotation angle with respect to the sub frame 30 reaches +60''. 1. In other words, the upper frame 40 is rotated upward in the direction away from the sub-frame 30.

Through the above control, the upper frame 40 to which the loading platform 20 is attached is rotated downward from the initial position in a direction approaching the sub-frame 30 by 5 m, and then the rotation angle with the sub-frame 30 is +60, which is the upper limit of rotation. Secondary frame 30 to the position of °
It is rotated upward in the direction away from the object. If the pipe reciprocating switch 65 continues to be operated, the upper frame 40 repeats between the position of the rotation angle of 60 degrees with respect to the sub frame 30 and the position closer to the sub frame 30 by 5 degrees. It moves up and down.

Next, the parallel mode and the lift control that can be operated in the parallel mode will be explained.

When the parallel mode is selected with the mode switch 61, even if the loading platform 20 is not parallel to the carrier body, the upper frame 40 and the sub-frame 30 are parallel to each other, and the sub-frame 30 and the main frame 10 are are parallel to each other, and the loading platform 20 becomes parallel when it is closest to the carrier body (the state shown in FIG. 4, 18). Then, when the lift switch 63 is operated, the loading platform 20 is raised and lowered relative to the transportation vehicle body while maintaining the parallel state of the loading platform 20 and the transportation vehicle body (the upper limit is the upper limit as shown in FIG. 4 (@)). The rotation angle of the frame 40 to the sub-frame 30 is +15 degrees, and the rotation angle of the sub-frame 30 to the main frame IO is 115 degrees. This operation is very effective, for example, when loading and unloading cargo with the loading platform of another truck or the like, because it allows the height positions of both loading platforms to be made the same.

Now, as described above, when the parallel mode is selected by the mode switch 61, the control section 74 checks whether the lift switch 63 is in the OFF state. If the lift switch 63 is in the OFF state, a parallel subroutine is executed to make the loading platform 20 parallel to the carrier body at the closest position. 3 is a flowchart showing the processing contents of this parallel subroutine.

When the processing of the parallel subroutine is started, the control section 74 first sets the parallel flag H (-0). The control unit 74
Next, the detected value FO of the front position sensor 51 and the detected value RO of the rear position sensor 52 are read, and the detected value FO of the front position sensor 51 is -l.

or more (but less than 0°), the front flag FF
Set (=l) L, also rear position sensor 52
When the detected value RO is below +1° (however, above 0°), the rear flag RF is set (-1).

The subsequent processing is performed when both flags PF and RF are set (-1''≦FO≦00 and 0°≦RO≦+l
°, that is, the absolute values of rain detection values FO and RO are both 1 or more),
When one flag FP or RF is in the cent state and the other is in the reset state (-1" ≦FO≦0° and RO>+1
', or FO<-1° and 0°≦RO≦+1'') or when both flags FF and RF are in the reset state (
This is executed in four cases: FO<-1" and RO>+1").

First, if both flags FF and RF are set (
-1°≦FO≦0° and 0°≦RO≦+1°), the upper frame 40 is considered to be parallel to the sub-frame 30 and the sub-frame 30 is parallel to the main frame 10, and the loading platform 20 is lifted from the main body. This control is not performed because the loading platform 20 and the main body are parallel to each other without being raised (the state shown in FIG. 4 (al)).

When the front flag FF is set and the rear flag RF is reset (-1°≦FO≦0°, RO>+1"), the subframe 30 is parallel to the main frame IO, so the loading platform 20 is not attached. It is sufficient to rotate only the upper frame 40, which is located in the upper frame 40, forward and downward in a direction approaching the sub-frame 30 so as to make it parallel to the sub-frame 30.

Therefore, if the detected value RO of the rear position sensor 52 is +4° or more, the control unit 74 directly excites the solenoid Sd3 until it reaches +4°, and relatively quickly moves forward in the direction approaching the upper frame 40 and the sub-frame 30. Rotate downward, and the detection m4IIRo of the rear position sensor 52 is +
If it is less than 4 degrees, a forward lowering speed limiting subroutine is executed and the front portion of the loading platform 20 is relatively slowly rotated downward in the forward lowering direction.

Conversely, the front flag FF is reset and the rear flag RF is reset.
is set (FO≦-1°, 0°≦RO≦+1
') Since the upper frame 40 is parallel to the sub frame 30, the sub frame 30 may be rotated in a direction approaching the main frame 10 to make it parallel to the main frame 10.
Therefore, the control section 74 controls the front position sensor 51.
If the detected value RO is less than 14°, the solenoids S1 and Sd2 are directly energized until the detected value RO reaches 14°.
0 relatively quickly in the direction approaching the main frame 1G, and the detected value RO of the front position sensor 51 is
If there is no drop at 14 degrees or more, the forward speed limit subroutine is processed and the sub frame 30 is changed to the main frame 10.
The front part of the loading platform 20 is rotated relatively slowly in the forward and upward direction.

When both flags FF and RF are in reset state (FO
1°, RO>+1°) is as shown in Fig. 18). Also in this case, if the absolute values of FO and RO are both greater than +4°, or both are less than +4°,
Processing is divided into four cases: one case is 4 degrees or less and the other case is greater than +4 degrees.

First, the detected value FO of the front position sensor 51 is 14.
° or more, the detection value RO of the rear position sensor 52 is +4
° or less, the process proceeds to the step shown in (18b) in FIG. After performing the steps once each, the process returns to the step of reading the detected values FO and RO of both body sensors 51 and 52. Therefore, the above process is repeated until either of the absolute values of the detection values RO and FO of both position sensors 51 and 52 becomes +4° or less (RO≧4° or FO≦4°), and the upper frame 40 Sub frame 3
0, and the sub frame 30 is relatively slowly rotated and lowered in the direction of approaching the main frame 10.

Detection of front position sensor 51 (iFO6<-
4° and the detection value R of the rear position sensor 52
If O is +4° or less, the control unit 74 first excites the solenoids S1 and Sd2 to rotate the subframe 30 until the relative rotation angle between the main frame 10 and the subframe 30 becomes +4° or less. After rotating downward in the direction approaching the main frame IO, the process proceeds to step (18b) described above.

The detection value FO car of the front position sensor 51 is smaller than 4°, and the detection value RO of the rear position sensor 52 is +
If the value is greater than 4°, the control grI section 74 first calculates the value of A of the detected value FO of the front position sensor 51, sets this value to Y, and repeats the process in other words until this value Y reaches 14°. If the detected value FO of the front position sensor 51 is 18
The sub frame 30 is rotated downward in the direction approaching the main frame 10 by energizing the solenoids S1 and Sd2 until the value Y is 14 degrees or more from the beginning (However, this process is omitted if the value Y is 14 degrees or more from the beginning. ). In this way, the value Y is 14°
(The detection value FO of the front position sensor 51 is 18 degrees.
), the value Y is replaced with the detection value NO of the loading platform sensor 53, and the process moves to the forward raising speed limiting subroutine. After the end of this front raising speed limiting subroutine, the control section 74 calculates the % value of the detection value RO of the rear position sensor 52, sets this value as Z, and maintains the rear position until this value Z reaches +4°. Detection value FO of sensor 52 is +8°
Excite the solenoid Sd3 until the upper frame 4
0 in the direction of approaching the sub-frame 30 (
However, if the value Z is +8° or less from the beginning, this process is omitted. In this way, when the value Z becomes less than +8° (the detected value RO of the rear position sensor 52 is +8°), the value Z is replaced with the detected value NO of the loading platform sensor 53, and the process shifts to the forward lowering speed limiting subroutine.

Through the above series of processes, both position sensors 51, 5
2 detected value FO, I? The absolute values of O are both +8° or less (FO≧−8°, +20≦+8°>).

Next, if the detected value FO of the front position sensor 51 is smaller than 14°, the control unit 74 excites the solenoids Sl and Sd2 until the detected value FO of the front position sensor 51 reaches 14°,
The main frame 10 is rotated downward in the direction of approaching the main frame 10, and then the forward speed limit subroutine is processed. Furthermore, if the detected value RO of the rear position sensor 52 is greater than +4°, the control unit 74 excites the solenoid Sd3 until the detected value RO of the rear position sensor 52 reaches +4°, and rotates the upper frame 40 downward in the direction of approaching the sub-frame 30. After that, the forward speed limit subroutine is processed.

Therefore, at the time when the processing of the parallel subroutine is started, the detected value RO of the rear position sensor 52 is +4°.
larger and the detection value F of the front position sensor 51
If O is less than 14 degrees, that is, if both of their absolute values are greater than 4 degrees, first adjust the upper frame 40 as necessary so that the absolute values of the rain detection values RO and FO are both 8 degrees. and the sub frame 30 is rotated downward, and then the rain detection values RO, F
The upper frame 40 and the sub-frame 30 are rotated downward as necessary so that the absolute values of O are both 4 degrees, and then the front raising speed limiting subroutine and the front lowering speed limiting subroutine are repeated to gradually lower the loading platform 20. is parallel to the carrier body.

Now, after the parallel subroutine has been processed as described above, by setting the height position of the loading platform 20 with respect to the main body using the lift switch 63, it is possible to control the lifting and lowering of the loading platform 20. The control contents of the lift subroutine for raising and lowering the loading platform 20 are shown in the flowchart of FIG.

First, the control unit 74 sets a flag [lRP, 1) PI? After resetting, the set value of the lift switch rotation 3 is read, and the detected value RO of the rear position sensor 52 and the detected value FO of the front position sensor 51 are read respectively. Then, the value D11 (= L-1
10), and the value D obtained by subtracting the detected value FO of the front position sensor 51 from the set value of the lift switch 63.
F (=L-FO) is calculated respectively.

Then, in the case of DR<OF and OF>1', the loading platform 2
Control for lifting up 0 is executed by energizing solenoids SL and Su2 and rotating the sub frame 30 upward in a direction away from the main frame IO (However, if I) F≦2° (The off-time toff is set to 22 times the on-time Ton and relatively slowly), and when OR<OF and OF<-1°, the control for lifting down the loading platform 20 excites the solenoids S1 and Su2 and lifts the subframe. 30 in the direction approaching the main frame IO and rotate the rear part of the loading platform 20 downward (However, in the case of OF2-2°, the off time Loff is set as 22 times the on time Ton for comparison. slowly) to return to [phase],
-1°≦OF≦l°, the solenoid excitation control is not performed and only the flag DFR is set, and if the flag DRP is set, it returns to [phase] and is reset. If so, the control is terminated.

On the other hand, if DR≧DF, the value OF is used in place of the value OR in the above process, so the solenoid Su3. Sd3 is excited and the upper frame 40 is rotated in a direction away from or toward the sub-frame 30 to raise and rotate the front part of the loading platform 20 to lift the loading platform 20 or lift the front part of the loading platform 20. Control is performed to lift down the loading platform 20 by rotating it downward. Then, the loading platform 20 passes horizontally and the value OF (or value DR
) becomes -1°, the flag DFR (or DI'R) is set and the process returns to [phase]. After this, the loading platform 20 is lifted up (or lifted down) by rotating the opposite side of the loading platform 20, and the loading platform 20 is lifted up (or lifted down) again.
0 passes the horizontal and the value OR (or the value OF> -1°
When this happens, the flag DFR (or [1PR) is set, so the process of this lift subroutine ends once. Then, when the loading platform 20 is lifted up to the height position set by the lift switch 63, I)
The process ends when R=O. Therefore, in this lift subroutine, the i1 rear part of the loading platform 20 is alternately raised by 1°, although it may be 2° at first, and the entire loading platform 20 is lifted up, or it is lowered to lift up the entire loading platform 20.
The whole thing lifts down.

〔effect〕

As detailed above, according to the present invention, it is possible to vibrate the loading platform of the transport vehicle by automatically moving it up and down within a predetermined angle range, so that the loading platform can be moved slowly while the transport vehicle is moving slowly. Work such as dispersing soil, etc. loaded on 8i on the ground surface is easily carried out, and since the vibration of the loading platform at that time is repeated within a predetermined angle range, it is difficult to spread soil, etc. evenly. It becomes possible.

[Brief explanation of the drawing]

The drawings show embodiments of the present invention, and FIG. 1 is a schematic perspective view of a transport vehicle equipped with the loading platform attitude device of the present invention,
The figure is a side sectional view seen from the right side, FIG. 3 is a plan view of FIG. 2, FIG. 4 is a schematic diagram showing each posture of the loading platform 20 of the carrier, and FIG. 5 is a schematic diagram of the operation panel. Fig. 6 is a hydraulic circuit diagram of the main parts of the transport vehicle, Fig. 7 is a block diagram of the control circuit of the device of the present invention, Fig. 8 is a flowchart of the main routine showing the processing contents of the control section, and Fig. 9 is a hydraulic cylinder drive Fig. 1θ is a flowchart of the automatic subroutine, Fig. 11 is a flowchart of the automatic lowering subroutine, Fig. 12 is a flowchart of the automatic raising subroutine, and Fig. 13 is a flowchart of the forward lowering speed limiting subroutine. Char1., Figure 14 is a flowchart of the forward raising speed limit subroutine, Figure 15 is a flowchart of the manual raise subroutine, Figure 16 is a flowchart of the manual lowering subroutine, Figure g417 is a flowchart of the vibration subroutine, and Figure 18 is the parallel subroutine. FIG. 19 is a flowchart of the foot subroutine. Sl, Su2. Su3. Sd2. Sd3...'Solenoid 3...Clutch lever 6...Operation panel I
O...Main frame 11...Crawler 12.
・・Shinaka-shi 20・・Loading platform 30・・Subframe 32・・Hydraulic cylinder 40・・Upper frame 43・・Hydraulic cylinder 51・・・Front position sensor 52・・・・Rear position sensor
53... Loading platform sensor 61... Mode switch
62...Loading platform switch 63...Lift switch 64...Cylinder speed selection switch 64
...Vibration switch 74...Applicant: Yanmar Agricultural Machinery Co., Ltd., patent attorney
Noboru Kono Domain 5 Calculation G Figure 11 Figure 12 Hand vt? Ili Positive IF (Method) November 15, 1985 Patent Application No. 160490 2, Name of Invention i! Loading platform posture of II transport vehicle - Control device 3, Relationship with the case of the person making the amendment, Patent applicant location 1-32 Chayamachi, Kita-ku, Osaka Name (6)
85) Yanmar Agricultural Machinery Co., Ltd. Representative Atsuo Yamaoka 4, Agent address 1-14 Shitennoji, Tennoji-ku, Osaka 0543
No. 22 Nisshin Building 207 Submission of appropriate drawings [Purity of planning! (No change in content)] 8. For one copy of the catalog correction drawing of the attached documents? Procedural amendment (voluntary) January 31, 1985 Patent Application No. 160490, filed in 1985 2, Name of the invention Transport vehicle cargo position control device 3, Relationship with the person making the amendment Patent applicant location Kita, Osaka City 1-32 Chayamachi Ward Name (685) Yanmar Agricultural Machinery Co., Ltd. Representative Yama
Atsushi Oka 4, Agent 543 Address 1-14-22 Shitennoji, Tennoji-ku, Osaka
Nisshin Building 207 Kono Patent Office (Tel: 06-779-3088) 6.
Contents of correction Figure 2, Figure 5, Figure 6, Figure 7, Figure 10, Figure 12, Figure 17, Figure 18 (a), 18th issue) and 19
The figures are corrected as shown in the attached corrected drawings. 7. List of attached documents + 11 corrected drawings 1 total drawing

Claims (1)

[Scope of Claims] 1. A loading platform posture control device for a transport vehicle configured to control the posture of the loading platform by rotating the loading platform in the front-rear direction with respect to a main frame equipped with a traveling device, comprising: A sensor is provided for detecting a rotation angle with respect to the main frame, and by receiving an instruction to vibrate the loading platform up and down, the upper frame moves in a predetermined direction away from the main frame according to the detection result of the sensor. The upper frame is repeatedly moved up and down between the angular position at the time the instruction is given and a predetermined angular position on the main frame side only when the upper frame is rotated by more than an angle. A loading platform posture control device for a transport vehicle, which is characterized by: