JPH0689534B2 - Automatic control snowplow - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatically controlled snow removing vehicle in which a part of snow removing work is automated, and is particularly suitable for high speed snow removing.

[0002]

2. Description of the Related Art In recent years, from the viewpoint of improving the efficiency of snow removal work, high-speed snow removal has become popular, in which snow removal is performed while running a snow removal vehicle at a high speed of 40 km / h or more.

However, in the conventional snow plow, the operator is required to perform various blade operations required during snow pruning work, such as adjusting the ground contact pressure of the blade, avoiding the blade from an obstacle, and reducing the width of the blade when approaching a narrow road. Since it had to be done by one person, the operation had to be performed in a shorter time as the speed of the snow removal vehicle increased, which caused an excessive burden and hindered safe driving. is there.

[0004]

SUMMARY OF THE INVENTION Therefore, the present invention provides a snow plow that reduces the burden on the operator by automating the blade operation during snow pruning work and enables safe and high-speed snow plucking. This is a technical issue.

[0005]

[Means for Solving the Problems] In the present invention,
Means adopted for solving the above problems will be described.

First, a plurality of split blades are slidably stacked to form a composite blade, and a shutter bracket that slides on a rail above the composite blade is provided with a shutter blade that can be raised and lowered through parallel links to remove snow. The detector detects the current snow removal width of the composite blade,
By calculating the position of the composite blade end with the shutter position controller from that value, and by adopting the means of sliding the bracket to the position corresponding to the calculated position of this blade end, the expansion and contraction of the blade due to the road width change We provided a snowplow that automates the shutter blade operation.

Further, a shutter blade is mounted on a bracket above the snow removing blade via a parallel link so that the shutter blade can move up and down, and a marker detector for the shutter detects a marker of a specific type installed on the road, and at this time, the shutter blade is detected. When the vehicle is in the raised position, the shutter opening / closing controller lowered the shutter to provide a snowplow that automatically stops snow throwing to the side at intersections and interchange branches.

Furthermore, the amount of exploration waves on the road is monitored by the oscillating element and the vibration receiving element, the snow condition of the road surface is estimated from the reflected wave amount, and the ground pressure of the blade is accordingly estimated. By adopting the means of adjusting
We have provided a snow plow that automatically selects the blade contact pressure that matches the snow conditions on the road surface.

Also, the engine speed, the amount of accelerator depression, the operation of the anti-locking brake system, and the operation of the limited slipping differential are monitored,
By adopting a means of weakening the blade ground contact pressure on the basis of these monitoring results, a snow removal vehicle that automatically selects the blade ground contact pressure according to the running state of the snow removal vehicle was provided.

Further, a rotatable tiltable blade is connected to a fluid pressure cylinder via a one-touch connection type separable joint made of male and female meshing materials, while a sensor monitors the fall of the blade due to the joint separation. Incidentally, when the sensor detects the tipping of the blade due to the separation of the joint, the controller extends the fluid pressure cylinder to connect the mating material of the joint, and then retracts the cylinder to return the blade to the original state. By adopting the means, a snow plow that automatically resets the blade after the operation of the blade safety mechanism is provided.

Further, when the blade is constructed so that it can be tilted to the left and right, and the temporary avoidance marker detector provided on the snow removing vehicle detects a specific type of marker previously installed on the road, the blade avoidance controller is activated. By adopting a means of raising only the right end of the blade to shift the blade to a temporary avoidance posture, a snow plow that automatically avoids the blade was provided.

[0012]

EXAMPLES The present invention will be described below based on examples.

On the lower surface of the chassis of the truck that employs the automatic transmission, there are fixedly mounted a pair of main brackets 16 and 16 arranged side by side in the front right and rear left directions. The first fluid pressure cylinders 14 and 14 are mounted on the brackets. It is pivotally installed. Also, this bracket has parallel links
The clearance cylinders 17 and 17 are connected to each other via 18, 18 ... And the rod end of the first fluid pressure cylinder 14 and 14 is also connected to the cylinders 17 and 17. When the fluid pressure cylinder expands and contracts, the cylinders 17 and 17 also move up and down. And, to this cylindrical body 17, 17, via the bracket, the pivot 15
・ 15 are arranged horizontally and in a one-way manner. Furthermore, this axis
The composite blade bracket 12 is pivotally mounted on the 15/15. This composite blade bracket 12 has a slide guide on the front surface, and two divided blades 11 and 11 having a slide guide on the rear surface are arranged in different steps in front of the divided blade located on the right side to form a composite blade. Constitute. In addition, the composite blade bracket 12 and the split blades 11 and 11
The second fluid pressure cylinders 13 and 13 are respectively installed between and, and when the second fluid pressure cylinders 13 and 13 extend, both split blades project laterally to widen the entire composite blade, On the contrary, when the second fluid pressure cylinders 13 and 13 are contracted, the divided blades 11 and 11 are closer to the center so that they overlap each other, and the width of the entire composite blade is narrowed.

Further, a triangle plate member 23 is provided on the upper rear surface of the composite blade bracket 12 pivotally mounted on the shaft 15.
The rod end of the third fluid pressure cylinder 24 is connected via a link constituted by the arc plate member 25 and a separable joint described later. Since the bottom end of this third fluid pressure cylinder 24 is pivotally supported by the frame carried out from the shaft,
When the third fluid pressure cylinder 24 extends, the entire composite blade falls forward and lies flat, and when the third fluid pressure cylinder 24 retracts, the entire composite blade rises. The separable joint is composed of a male mesh member 21 fixed to the composite blade bracket 12 and a female mesh member 22 fixed to a link pivotally provided at the rod end of the third fluid pressure cylinder 24. The composite blade bracket 12 and the link are connected by engaging the concave and convex portions of both the meshing members 21 and 22 with each other. This meshing is made by strip-shaped teeth extending parallel to the blade surface of the composite blade and extending in a direction perpendicular to the link when the blade is upright. Therefore, the engagement of the teeth is strong in the direction of separating the composite blade bracket 12 and the link. Further, since the link is pivotally provided not only on the fluid pressure cylinder but also on the shaft 15, even if the separable joint is separated into two, the female mesh member 22 is kept at a predetermined distance from the shaft 15. It is supposed to be. Therefore, after the separation of the separable joint, only by extending the third fluid pressure cylinder 24, the male meshing member 21 and the female meshing member 22 meet again and mesh with each other.

Above the composite blade, a frame 36 having rails is arranged. Then, the shutter bracket 34 is held on the rail in such a state that it can be moved back and forth by the expansion and contraction of the fifth fluid pressure cylinder 35. The bracket 34 is arranged so as to be taken out to the left end side of the blade, and the parallel links 33, 33 are attached to the taken out tip.
Is rotatably provided. Parallel links 33, 33 are 2 each
It has a shape that the rods of the book are reinforced with a cauldron,
The shutter blade 31 is supported at the end of the link opposite to the bracket, and the direction of the blade surface is expanded and contracted by the expansion and contraction of the fourth fluid pressure cylinders 32, 32 installed between the shutter bracket 34 and the shutter blade 31. Swings up and down while being kept constant.

The first to fifth fluid pressure cylinders described above have independent fluid supply pipes and fluid discharge pipes, and electromagnetic operating valves 6a, 6a, ... Are provided in the respective pipes. However, by opening and closing this solenoid operated valve, it is possible to expand and contract independently. Further, in the first fluid pressure cylinder, a pressure control valve 6b is also provided in the pipeline so that the pressure of the fluid in the cylinder can be maintained at a desired value.

The solenoid operated valve and the pressure control valve related to the expansion and contraction of these fluid pressure cylinders are operated by the snow removal controller 4 provided in the cab of the truck. The snow removal controller 4 employs a microcomputer, and appropriately operates a valve based on information input to the microcomputer to control expansion / contraction of a fluid pressure cylinder to perform a blade operation required for snow removal work.

The input device of this microcomputer includes
Eight types of push-button type switches (automatic mode switch 5a, forwarding mode switch 5b, work standby mode switch 5c, grounding mode switch 5d, pressing mode switch 5e, temporary avoidance mode switch 5f, side shutters arranged on the upper surface of the controller 4 Open switch 5g and side shutter close switch 5h), 3 types of slide type setting shots (pressing pressure setting shot 5i, left and right balance setting shot 5j, blade width setting shot 5k) and the lower part of the front of the track Two types of marker detectors (shutter marker detector 5l, temporary avoidance marker detector 5m), ultrasonic receiving elements 5n and 5n provided on the front lower surface and rear lower surface, one on the rear surface and one on the rear surface. Only one photoelectric receiving element 5o, blade sensor 5p arranged on the composite blade bracket 12
And a snow removal width detector 5q, a rotation speed detector 5r connected to an engine tachometer, a speed detector 5s connected to a speedometer, and a braking sensor 5 that outputs a signal in conjunction with a truck anti-locking brake system.
t, a grip sensor 5u that outputs a signal in conjunction with the limited slipping differential, and an accelerator sensor 5v that monitors the amount of depression of the accelerator. Further, the output device of the microcomputer, the electromagnetic operation valve 6a · 6a ·
..., in addition to the pressure control valve 6b, a work state indicator 6c arranged in the operator's cab, ultrasonic oscillating elements 6d and 6d provided on the front lower surface and rear lower surface of the truck, and a probe light oscillating element 6e on the rear lower surface of the truck. Is adopted.

Of the above-mentioned input devices, an automatic mode switch button, a forwarding mode switch button, a work standby mode switch button, a grounding mode switch button, a pressing mode switch button, a temporary avoidance mode switch button, etc. are pressed, When a signal is input to the microcomputer, the microcomputer operates the blade according to the switch. Hereinafter, this blade operation will be described in detail.

First, a brief description will be given of various blade operations that are most basically performed when the mode switch is selected. In this mode, the blades are moved up and down, pressed and the left and right balances are adjusted, rotated, and the width is expanded and contracted. Each operation of raising and lowering the shutter blade is executed. Of these operations,
Raising and lowering of the blade is performed by expansion and contraction of the first fluid pressure cylinder, and pressing of the blade reduces the fluid pressure in the first fluid pressure cylinder with the first fluid pressure cylinder extended and the blade lowered. It is carried out by maintaining a predetermined value. At the time of this pressing, the left and right balance of the blade pressing is adjusted depending on whether the two first fluid pressure cylinders have the same fluid pressure or the two fluid pressures are left and right separately.

Further, the microcomputer realizes the work modes of the five kinds of composite blades by the above blade operation. The first working mode is the forwarding mode,
This is accomplished by retracting the first fluid cylinder of the book together and extending the third fluid pressure cylinder to lay down the blades and float the entire surface off the road. The second work mode is a work standby mode and is achieved by retracting the two first fluid cylinders together and retracting the third fluid pressure cylinder so that the edge is lifted from the road surface while the blade is standing upright. To be done. The third working mode is the grounding mode, in which the two first fluid pressure cylinders are extended to a predetermined length and the third fluid pressure cylinders are retracted so that the blade is raised and the edge is slid on the road surface. Achieved by keeping in. The fourth work mode is the pressing mode, in which the third fluid pressure cylinder is retracted,
This is achieved by applying a predetermined fluid pressure to the inside of each of the two first fluid pressure cylinders to extend the cylinders, and pressing the edge of the blade against the road surface with a predetermined ground pressure. At this time, if the fluid pressures inside the two first fluid pressure cylinders are changed, the pressing state in which the ground pressure is different between the left and right is achieved. Finally, the fifth work mode is the temporary avoidance mode, in which the third fluid pressure cylinder is retracted and the two first work modes are used.
From the state in which the predetermined fluid pressure is applied to each inside of the fluid pressure cylinder and the fluid pressure cylinder is extended, only the first fluid pressure cylinder on the right side is retracted by a predetermined amount, and the left end of the blade is grounded,
This is accomplished by slightly lifting the right edge of the blade above the ground.

The realization of these five work modes is selected according to which of the six work mode selection switches is selected.

First, when selecting the automatic mode switch,
Based on the information from other input devices, the microcomputer selects the most suitable mode from the above-mentioned five working modes, namely, the pressing mode, the grounding mode, and the temporary avoidance mode, and realizes that mode. The information that serves as the basis for this selection is detection information for temporary avoidance markers, truck speed information, engine speed information, accelerator depression information, anti-locking brake system operation information, limited slipping differential operation information. , Road surface state information, ground pressure setting value information, and left / right balance setting value information.

Among these pieces of information, the detection information of the temporary avoidance marker has the highest priority as a judgment criterion, and when the temporary avoidance marker is detected, the blade is temporarily moved to the avoidance state. . This temporary avoidance marker detection information is, for example, by the temporary avoidance marker detector detecting the temporary avoidance marker previously buried in front of the place where there is an obstacle caught on the blade such as a bridge joint. Provided. The temporary avoidance marker needs to be, for example, an oscillator that oscillates an electromagnetic wave of a specific frequency in order to distinguish it from other types of markers. Alternatively, a marker is constructed by embedding a ferrite magnetic material in a specific pattern such as a bar code that is identified by its width and number, and the marker detector is composed of an electromagnetic coil and a ferrite sensor. A method of recognizing that the road surface is magnetized by the ferrite sensor may be adopted. In addition, the microcomputer is set in advance for the time required to pass a location with an obstacle from the standard traveling speed of the snowplow, and after the temporary avoidance marker is detected and the temporary avoidance mode is entered, After waiting for the passage of the required time, the snow removal mode is always restored.

The track speed information, the engine speed information and the accelerator depression amount information, the anti-locking brake system operation information, and the limited slipping differential operation information are the temporary avoidance marker detection information. Next, the priority as a criterion is high. These pieces of information are input to the microcomputer from the speed detector, the rotation speed detector and the accelerator sensor, the braking sensor, and the grip sensor, respectively. And
The microcomputer shifts the blade to the ground mode when the speed of the track input from the speed detector is equal to or lower than a predetermined value. Efficient snow removal requires a certain amount of speed, and a state where the speed is below a certain value is a transient state that is either trying to stop or accelerating from now on. If so, pressing the blade against the road surface is a major obstacle to acceleration. Further, the microcomputer reduces the ground pressure of the blade when the engine speed input from the rotation speed detector is equal to or lower than a predetermined value and the depression amount input from the accelerator sensor is equal to or higher than the predetermined value. . In order to accelerate by depressing the accelerator while pressing the blade against the road surface, a considerable amount of engine torque is required, and when acceleration is required but the engine speed drops below a certain value, the engine load is lightened. This is because it is necessary to increase the number of rotations. The accelerator sensor detects the amount of depression by monitoring the amount of movement of the wire end connected to the accelerator. Furthermore, when the detection information of the operation of the anti-locking brake system is input from the braking sensor, the microcomputer reduces the ground pressure of the blade by a predetermined amount. The operation of the anti-locking brake system generally occurs when the tire is about to slip during sudden braking, and in such a case, the contact pressure of the one-sided blade is relaxed to increase the grip force of the tire and also from the road surface. This is because it is necessary to prevent the track from skidding due to the force applied to the blade. Further, when the limited slipping differential is activated, the microcomputer reduces the ground pressure of the blade by a predetermined amount. This is because the operation of the limited slipping differential is caused by the slip of the tire, and in such a case, it is necessary to reduce the ground contact pressure of the blade to enhance the grip force of the tire. It should be noted that the sum of the pressing pressure of the blade and the load applied to each tire is approximately equal to the weight of the entire snow removing vehicle. Therefore, if the pressing pressure is reduced, the load applied to the tire increases and the grip force increases.

The road surface state information is used as a criterion for determining the working mode, such as temporary avoidance marker detection information, truck speed information, engine speed information and accelerator depression amount information, anti-locking brake system operation information, and limiteds. It is inferior to the operation information of the ripping differential. Then, only when the blade operation condition based on the priority information is not satisfied, the blade operation determination criterion is obtained. The road surface state information has priority over the ground pressure setting value information and the left-right balance setting value information, but like the ground pressure setting value information and the left-right balance setting value information, keeps the blade in the snow removal mode. This road surface state information will be described in detail. This information can be obtained from the ultrasonic wave receiving element and the photoelectric receiving element on the lower surface of the track. The ultrasonic wave receiving element receives the ultrasonic waves emitted by the ultrasonic wave oscillating element whose output is controlled by the microcomputer, which is reflected on the snow surface or the road surface and returns, and outputs an electric signal corresponding to the energy amount. Input to microcomputer. The energy amount of the reflected wave is proportional to the amount of ultrasonic waves reflected from the snow surface on the road surface. As a result of the test, it was found that the greater the amount of snow, the more the ultrasonic waves are absorbed by the snow than the amount of the ultrasonic waves reflected on the snow surface. It is known that the ultrasonic reflectance increases, so by comparing with the conventional data,
The state of snow on the road surface before snow removal can be known from the amount of energy of reflected waves captured by the vibration receiving element on the front side of the truck. Further, it is possible to monitor whether the road surface is exposed by completely removing snow behind the blade from the amount of energy of the reflected wave captured by the vibration receiving element on the rear side of the track.
Then, when the amount of ultrasonic waves reflected from the road surface before snow removal is less than a predetermined threshold value and the state of snow is larger than the predetermined condition or the snow surface is hard, the microcomputer determines that the blade Increase the ground pressure above the current value. Also, when the amount of ultrasonic waves reflected behind the blade is lower than the threshold value for sufficient snow removal, and when it can be determined that the snow has been completely removed and the road surface is not exposed, the ground pressure of the blade is also set. increase. Actually, when the snowplow travels, the chassis of the truck vibrates, and the distance of the oscillation element or the vibration receiving element from the road surface changes. Therefore, in order to determine the snow accumulation state before snow removal and the road surface exposure after snow removal, it is necessary to temporally average the amounts of energy of the reflected waves obtained by the vibration receiving element before making the determination. However, depending on the road surface condition, the vibration of the chassis may become so large that it may be difficult to make a judgment even if time averaging is performed.
In this case, only the road surface condition after snow removal is determined by the photoelectric type vibration receiving element provided at the rear of the truck. Since the paved road surface has a lower light reflectance than the snow surface, it can be judged that snow can be completely removed and the road surface is exposed only when the amount of reflected energy of the exploratory light emitted by the oscillation element falls below a specified value. . When it is determined that the road surface is not exposed, the microcomputer increases the ground contact pressure of the blade.

Temporary avoidance marker detection information, truck speed information, engine speed information and accelerator depression amount information, anti-locking brake system operation information,
When the priority information such as the operation information of the limited slipping differential is out of the condition for blade operation determined by the microcomputer, the microcomputer shifts the blade to the snow removal mode. At this time, the ground pressure of the blade follows the ground pressure setting value information and the left-right balance setting value information. The ground pressure setting value information is input by pressing pressure setting shooting, and the left and right balance setting value information is input by left and right balance setting shooting. The microcomputer corrects the ground pressure setting value information based on the left-right balance setting information, loads predetermined fluid pressures inside the left and right first fluid pressure cylinders, and presses the blades according to the shooting settings. Of.

Further, the microcomputer selects any of five kinds of work mode selection switches (forwarding mode switch, work standby mode switch, grounding mode switch, pressing mode switch, temporary avoidance mode switch) other than the automatic mode switch. If so, the blade is moved to a work mode corresponding to each switch. After this selection, the same work mode is maintained until one of the other work mode switches including the automatic mode switch is selected.

In addition, the microcomputer has the current blade regardless of which of the five modes the blade is in, and which of the six operation mode selection switches is selected. According to width
Controls the sliding of the shutter bracket. First, a snow removal width detector that employs a rotary encoder measures the current amount of overhang of the divided blades, and the microcomputer calculates the current blade width. At the same time,
The microcomputer calculates the position of the left end of the blade, and when the shutter blade is closed, the shutter bracket is slid so that the shutter blade is slightly left of the left end position of the blade.

The width of the blade is basically irrespective of which of the six working mode selection switches is selected and which of the five modes the blade is in. Width setting The microcomputer expands and contracts according to the width set by shooting. Therefore, when the blade width setting shot is moved, the blade width and the shutter position change simultaneously.

Further, in principle, the shutter blade is opened and closed by the microcomputer when the side shutter open switch and the side shutter close switch are selected. However, when the automatic mode switch is selected and a marker is detected by the shutter marker detector, the shutter blade is opened and closed. This shutter marker can have a structure similar to that of the temporary avoidance marker, and must be placed at both ends of a section where snowfall should be stopped, such as an intersection. When the snow removal vehicle approaches this section with the shutter blade open, the shutter marker detector detects the first shutter marker, the microcomputer closes the shutter blade, and the snow removal vehicle concerned. When passing the section, the shutter marker detector detects the second shutter marker, and the microcomputer closes the shutter blade.

Further, the microcomputer adopts the proximity switch when the edge of the blade is caught by an obstacle and flips over, regardless of which of the six work mode selection switches is selected. The blade sensor detects this, and after a sufficient time has passed for the blade to pass over the obstacle, the third fluid pressure cylinder is extended and retracted to return the blade to the standing state.

Further, the microcomputer, regardless of which of the six work mode selection switches is selected, displays the current blade mode and the reflected wave detected by the vibration receiving element on the work status indicator in the cab. By displaying the snow cover information before snow removal based on the amount of energy, the presence or absence of road surface exposure after snow removal, and the opening or closing of the shutter blades, the operator can directly check the blade status without directly observing the blades at the rear from the driver's seat. To confirm the blade operation.

[0034]

INDUSTRIAL APPLICABILITY As described above, the snow plow of the present invention reduces the burden on the operator by automating the blade operation during snow pruning work and realizes safe and high-speed snow pruning. high.

[Brief description of drawings]

FIG. 1 is a side view of an embodiment.

FIG. 2 is a plan view of the embodiment.

FIG. 3 is a side view of the embodiment with the shutter blade omitted.

FIG. 4 is a plan view of the embodiment with the shutter blade omitted.

FIG. 5 is a plan view of a composite blade (standing state) in the example.

FIG. 6 is a side view of the composite blade in the example.

FIG. 7 is a rear view of the composite blade in the embodiment in which the first fluid pressure cylinder and the third fluid pressure cylinder are omitted.

FIG. 8 is a cross-sectional view of the composite blade (standing state) in the embodiment, with the upper part omitted.

FIG. 9 is a cross-sectional view of the composite blade (with the joints separated) in the embodiment, with the upper part omitted.

FIG. 10 is a sectional view of a separable joint (connected state) in the example.

FIG. 11 is a cross-sectional view of a separable joint (transitional state) in the example.

FIG. 12 is a sectional view of a separable joint (separated state) in the example.

FIG. 13 is a rear view of the shutter blade in the embodiment.

FIG. 14 is a plan view of the shutter blade in the embodiment.

FIG. 15 is a plan view of the snow removal controller in the embodiment.

FIG. 16 is a block diagram illustrating the operation of the microcomputer in the embodiment.

FIG. 17 is a side view illustrating the temporary avoidance mode of the blade in the embodiment with the shutter blade omitted.

[Explanation of symbols]

 11 Split blade 31 Shutter blade

Front page continuation (72) Inventor Shigeo Iwasaki 1-35 Bunkyo, Fukui City, Fukui Prefecture Iwasaki Industrial Co., Ltd. (72) Inventor Ken Kai Kai Ishimoricho, Fukui City 30-7

Claims (9)

[Claims] 1. A composite blade that changes the snow removal width of the entire blade by stacking a plurality of divided blades in a laterally slidable manner and sliding the two divided blades, and a current snow removal width of the composite blade. A snow removal width detector for detecting, a shutter bracket that moves forward and backward from the frame toward the end of the composite blade by sliding on a rail horizontally arranged in the frame provided above the composite blade, and a parallel link. The shutter blade mounted vertically on the bracket and the current value of the snow removal width detector calculate the position of the composite blade end, and slide the shutter bracket to the position corresponding to the calculated position of this blade end. An automatic control snowplow having a shutter position controller for controlling. 2. A shutter bracket provided above the snow removing blade, a shutter blade mounted on the bracket so as to be able to move up and down via a parallel link, and a shutter marker for detecting a specific type of marker installed on a road. An automatic control snowplow having a detector and a shutter opening / closing controller that lowers the shutter when the shutter marker detector detects a marker when the shutter blade is in the raised position. 3. The shutter opening / closing controller is configured to raise the shutter blade when the shutter marker detector detects a marker when the shutter blade is in the lowered position. The automatic control snow removal vehicle according to claim 2. 4. A blade that moves up and down due to expansion and contraction of a fluid pressure cylinder and is pressed against a road surface, an oscillating element that is provided on the lower surface of a snow plow and emits an exploration wave toward the road surface, and a reflected wave generated when the exploration wave is reflected by the road. From the amount of energy of the reflected wave received by the receiving element and the receiving element that detects
An automatic control snow removal vehicle, comprising: a snow cover determiner that estimates the state of snow on the road surface that reflects the exploration wave and that operates a fluid pressure cylinder to adjust the pressing pressure based on the estimation result. 5. A rotation speed detector for measuring a rotation speed of an engine per unit time, an accelerator sensor for detecting an accelerator depression amount, a blade capable of adjusting a ground pressure by a fluid pressure cylinder, and a rotation speed detector. When the detected engine speed is equal to or lower than a predetermined value, and the accelerator pedal depression amount detected by the accelerator sensor is equal to or higher than a predetermined value, a ground pressure controller for reducing the ground pressure of the blade is provided. Automatically controlled snowplow. 6. A braking sensor for detecting the operation of the anti-locking brake system, a blade whose ground pressure can be adjusted by a fluid pressure cylinder, and a grounding of the blade when the operation of the anti-locking brake system is detected by the braking sensor. An automatic control snowplow having a ground pressure controller for reducing pressure. 7. A grip sensor for detecting the operation of the limited slipping differential, and a ground pressure controller for reducing the ground pressure of the blade when the operation of the limited slipping differential is detected by the grip sensor. An automatic control snowplow featuring. 8. A retractable blade pivotally supported on a horizontal shaft at a lower portion of a vehicle, and a male mesh member and a female mesh member in which at least one mesh member is biased toward another mesh member. , A separable joint meshing with each other, a link member connected to the upper part of the rear surface of the collapsible blade via the separable joint, a fluid pressure cylinder connected to the link member, and both separable joints A blade sensor that detects that the material has separated and the collapsible blade has fallen down, and when the collapsible blade has fallen detected by the blade sensor, after a certain period of time, the fluid pressure cylinder is extended by a predetermined amount and both of the separable joints are separated. An automatic control snow removal vehicle, comprising: a blade return controller that restores the retractable blade to the snow removal state by retracting the fluid pressure cylinder to the original length after the engagement material is engaged again. 9. A pair of left and right fluid pressure cylinders, which are diagonally arranged to the front right and left rear of the vehicle, and are independently hung from the pair of fluid pressure cylinders via a clearance mechanism. Blades arranged so that the left and right ends can be individually raised and lowered, a temporary avoidance marker detector that detects a specific type of marker installed on the road, and a predetermined fluid pressure inside the left and right fluid pressure cylinders. Is added, when the blade is pressed against the ground, when the temporary avoidance marker detector detects a marker, the right fluid pressure cylinder is retracted by a predetermined amount to put the blade in a temporary avoidance posture. An automatic control snowplow having a blade avoidance controller for shifting.