JPS6156728B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an automatic speed control device for operating a rotary snowplow at an optimal snow-throwing speed.

[Conventional technology]

FIG. 6 is a schematic diagram showing the structure of a well-known rotary snowplow, in which 1 is a rotary snowplow, 2 is a driving engine for driving the rotary snowplow 1, 3 is an impeller for throwing snow, and 4 is an impeller. 3 (hereinafter referred to as a snow-throwing engine) is a raking blade that scrapes up snow, and 6 is a cylinder that opens and closes the raking blade 5.

As the rotary snowplow 1 advances, snow 8 on the travel path 7 and its vicinity is collected by the raking blades 5, and is thrown to the outside of the travel path 7 by the impeller 3 as shown by an arrow 9 to complete the snow removal work. It is done.

[Problem that the invention seeks to solve]

The snow removal capacity of the rotary snowplow is limited by the output of the snow-throwing engine 4 or the snow-throwing volume determined from the volume and rotational speed of the impeller 3, whichever is smaller, and cannot throw more snow. On the other hand, the amount of snow shoveled by the rotary snowplow 1 is closely related to the running speed and the amount of snow, and the rotary snowplow 1 needs to drive while shoveling an amount of snow commensurate with its snow throwing ability. If more snow is shoveled than the snow throwing capacity, the path from the shoveling blades 5 to the snow throwing mouth becomes clogged and the snow throwing engine 4 becomes under load, which not only reduces the snow throwing capacity but also leads to derailment, which is the worst situation. There were problems such as the risk of causing The present invention aims to avoid such a situation and to obtain an automatic speed control device that calculates the optimum traveling speed in order to perform snow removal work as effectively as possible.

[Means for solving problems]

The automatic speed control device for a rotary snowplow according to the present invention includes a load state detection means for detecting the load state of a snow-throwing engine, and a load factor calculation means for calculating a load factor based on the load state detected by the detection means. , the smaller of the capacity limit due to the output of the snow-throwing engine and the capacity limit from the snow-throwing volume as a rotary snowplow is the snow-throwing capacity limit of the snow-throwing engine, and the load factor corresponding to this snow-throwing capacity is determined. A reference load factor data memory means for storing in memory as a snow throwing ability limit reference value, a speed detecting means for detecting the actual speed of the rotary snowplow, the load factor, arithmetic means, a reference load factor data memory means, and a speed detecting means. and an optimal snow-throwing speed calculation means for calculating the optimal snow-throwing speed based on the.

[Effect]

The result of taking the ratio of the load factor corresponding to the load state of the snow throwing engine calculated by the load factor calculation means and the reference load factor stored in the reference load factor data memory means, and correcting the actual vehicle speed. By setting this as the optimum snow throwing speed and setting this as the target speed, speed control is performed to achieve optimal snow throwing.

〔Example〕

Referring to the figures below, the relationship between various factors of the basic idea for constructing this invention will be specifically described. The rotary snowplow has the same structure as the conventional one.

Factors that control snow throwing ability include: (a) Limit of snow throwing ability due to horsepower of snow throwing engine 4.

(b) Limits on snow throwing capacity from snow throwing volume.

There are two. The relationship between (a) and (b) can be easily understood by comparing a snowplow to a water tank and a pump.

That is, in FIG. 2, the limit of the drainage capacity of the pump 101 is the limit of the snow-throwing capacity due to the horsepower of the snow-throwing engine 4, and the system surrounded by the broken line in FIG. The fact that the water tank 104 with the mouth 102 and the water supply port 103 cannot be drained in time for the water supply and the water tank 104 overflows can be said to be the limit of the snow throwing capacity based on the snow throwing volume. These will be explained below.

(a) Snow-throwing capacity based on horsepower of the snow-throwing engine 4 In order to throw snow, the snow-throwing engine 4 needs to give kinetic energy to the snow. The kinetic energy given to snow is expressed by the following equation (1).

75・P・ηa=1/2・W/g・V ² −(1) Formula P: Snow throwing engine horsepower (PS) ηa: Efficiency W: Snow processed per second (Kg) g: Gravity Acceleration (m/sec ² ) V: Initial speed of snow throwing (m/sec) Furthermore, W (snow processed in 1 second) in equation (1) is expressed by the following equation.

W = 1/3.6γVe - (2) γ: Specific gravity of snow (ton/m ³ ) Ve: Snow processed in 1 hour (m ³ /h) Also, V in equation (1) (initial speed of snow throwing ) is expressed by the following formula.

V=πθ/60・n - Equation (3) n: Impeller rotation speed (rpm) θ: Impeller average diameter (m) n (impeller rotation speed) in equation (3) is Since the impeller is rotated by a fluid coupling, it is given as the following formula.

n=K ₁ en ₀ − (4) formula K ₁ : Efficiency e: Fluid coupling output rotation speed ratio when driven via fluid coupling (=output n ₂ /input n ₁ ) no: rotation of snow throwing engine By substituting equations (2), (3), and (4) into equation (1), we obtain the following equation.

γVe=K ₂ P・ηa/e ²・n ₀ ² − (5) Formula γVe: Amount of snow treated in 1 hour (ton/h) (K ₂ = 75・7.2・g・1/K ₁ ²・(60/πθ) ²
= constant) The amount of snow processed in one hour (γVe) is calculated as follows: When rotary snowplow 1 travels at speed Vb (Km/h),
If the snow removal cross section of the rotary snowplow 1 is A (m ² ), it is assumed that γAVb×10 ³ (ton) of snow enters the rotary snowplow in one hour and all of it is processed, and γVe = γAVb×10 ³ −(6) Therefore, by substituting equation (6) into equation (5), the following relational expression is established.

γAVb=K ₃・P・ηa/e ²・n ₀ ² −Equation (7) (K ₃ = 1/10 ³・K ² = constant) Equation (7) is the engine speed and engine torque output of the diesel engine. Varies based on characteristics. This output characteristic of engine speed and engine torque is already known as shown in Figure 3 (February 10, 1970, Koyusha, "Overview of Diesel Locomotives"), and according to this, equation (7) can be expressed as Draw the characteristics as shown in Figure A. _N1 to _N5 indicate differences in notches. In FIG. 4, the vertical axis is the amount of snow removed, and the horizontal axis is the engine speed. From equation (7), ideally the characteristic should be a hyperbola that is inversely proportional to the rotational speed, but as shown in Figure 3, the change in torque is smaller than the change in rotational speed at low rotational speeds. The characteristics are as shown in Figure A. (P is proportional to torque).

(b) Snow-throwing capacity from the snow-throwing volume As mentioned above, the point at which the water in the tank spills in the system surrounded by the broken line in Figure 2 is the snow-throwing capacity from the snow-throwing volume. The snow-throwing capacity from this snow-throwing volume depends on the snow filling rate (snow quality), the effective volume of the impeller (equivalent to the volume of the water tank in Figure 2), the effective rotation speed of the impeller (the drain opening in Figure 2), (equivalent to the drainage capacity of) etc.

That is, the snow throw volume Vc is expressed as follows.

Vc = Vf・η ₂・60n (m ³ /h) − (8) formula η ₂ : Impeller volumetric efficiency (snow filling rate) Vf: Impeller effective volume (m ³ )... Eigenvalue n: Impeller Rotation speed (rpm) The rotation speed of the impeller is expressed as n=K ₁ en ₀ from equation (4), so by substituting this into equation (8), we obtain the following relationship as shown in equation (9).

Vc＝K ₄・Vf・η ₂・e・n ₀ (m ³ /h) − Equation (9) (K ₄ = 60K ₁ ) Expressing the volume of thrown snow in terms of weight, it becomes as shown in Equation (10) γVc =K ₄・Vf・η ₂・γ・e・n ₀ (ton/h)
-Equation (10) γVc is the amount of snow processed in one hour,
As mentioned above, the rotary snowplow 1 has a speed of Vb.
(Km/h) and the snow removal cross section of rotary snowplow 1 is A (m ² ), γAVb×10 ³ per hour
(ton) of snow enters the rotary snowplow and is all processed, γVc = γAVb×10 ³ −(11) Therefore, from equations (11) and (10), the following relational expression can be obtained.

γAVb＝K ₅・η ₂・γ・e・n ₀ (ton/h)
-(12) formula (K ₅ =1/10 ³ ·K ₄ ·Vf) (12) formula gives a characteristic diagram as shown in FIG. 4B. From equation (12), the rotation speed (n ₀ ) of the snow-throwing engine is proportional to the amount of snow removed γAVb, and the straight line slopes upward to the right. However, since the rotation speed of the snow-throwing engine has a certain output characteristic ( 2
(See figure) It will look like Figure 4B.

In addition, _η2・γ is defined as snow throwing information, and “η
In _other words, it is the value obtained by multiplying the degree of snow clogging in the drum by the specific gravity "γ", so the product multiplied by the drum volume (effective volume of the impeller) can be accommodated in the drum of a rotary snowplow at once. It refers to the possible weight of snow, and there is a relationship where η ₂・γ = constant.In other words, when snow specific gravity γ is small, volumetric efficiency η ₂ increases due to smooth snow, and conversely, when snow specific gravity γ is large Volumetric efficiency η ₂ decreases because of the snow.
The value of η ₂ ·γ can be changed depending on the opening/closing angle of the raking blades 5, the shape of the snow-throwing impeller 3, etc. In Fig. 4, B and C are obtained by changing η ₂ and γ to K ₁₀ and K ₂₀ , respectively, and K ₁₀ > K ₂₀
It is.

Based on the relationships described above, rotary snowplow 1
The limit of snow-throwing capacity is the lower of ``the limit of snow-throwing capacity based on the horsepower of the snow-throwing engine'' and ``the limit of snow-throwing capacity based on the snow-throwing volume'', that is, the intersection point in Figure 4. a to e (when η ₂ · γ = K ₁₀ ) and a' to e' (when η ₂ · γ = K ₂₀ ).

However, for only the _N5 notch with η ₂・γ = K ₁₆ , the snow throwing volume is larger than the snow throwing capacity of the snow throwing engine horsepower, so a is the rated load of the snow throwing engine horsepower. This point is the limit of the snow throwing ability of a rotary vehicle.

In this way, the limit of the snow throwing ability of the rotary snowplow 1 is not necessarily determined only by the horsepower of the snow throwing ability. For this reason, the intersection points a to e or a' to e' of the snow throwing capacity limits are converted into the load factor of the snow throwing engine 4, and the data is preset in the data memory means as the standard load factor _S0 , and the snow throwing operation is carried out. Compare with the actual load rate S of the snow throwing engine inside, calculate the amount of speed increase or deceleration,
Command the optimal snow throwing speed. FIG. 5 shows the relationship between the optimum snow throwing speed and the amount of snow removed. FIG. 1 is a block diagram showing an embodiment of the present invention.
is a load state detection device that detects the snow throwing load state of the snow throwing engine 4 of the rotary snowplow 1 by detecting the displacement of the easy scale proportional to the fuel injection state of the snow throwing engine 4 of the rotary snow blower 1. , 11 is the notch command information of the snow-throwing engine, 12 is the snow-throwing information that changes the standard load factor such as η ₂ and γ, 13 is the speed generator which is a speed detection means for detecting the current vehicle speed, and 14 is the load state A load factor calculating means for calculating the load factor S based on the output of the detection device 10, and a data memory 15 for storing the snow throwing ability limit reference value based on the notch command information 11 and the snow throwing information 12 as the standard load factor _S0 . Means 16 is a ratio calculation circuit for calculating the ratio (S/S ₀ ) between the actual load factor S and the reference load ratio S ₀ , and 17 is a ratio calculation circuit that calculates the optimum snow throwing speed Vs from the output of the ratio calculation circuit 16 and the output of the speed generator 13 Optimal snow throwing speed calculation means for calculating
18 is a detection means for detecting the difference between the optimum speed Vs which is the output of the optimum snow throwing speed calculating means 17 and the output of the speed generator 13; 19 is a means for outputting power running and braking commands based on the output of this detection means 18. It is a power running and brake control device.

The automatic speed control device configured as described above calculates the optimum snow throwing speed based on the input information from the load state detection means 10 to the speed generator 13, but it is possible to calculate the optimum snow throwing speed by using the input information from the load state detection means 10 to the speed generator 13. It is converted into the load factor of the engine, and the value is set in advance in the data memory means ₁₅ as the reference load factor S0. The load condition detected by the load condition detection means 10 is converted into a load factor S by the load factor calculation means 14, S ₀ /S is calculated by the ratio calculation circuit 16, and this output and the output of the speed generator 13 are optimally set. Enter the snow speed and select S ₀ /S・
The optimum snow throwing speed calculation circuit 17 calculates Va and calculates the optimum snow throwing speed Vs. This optimal snow throwing speed Vs
is compared with the actual speed which is the output from the speed generator 13, and the output difference is detected. This output difference is input to the power running and brake control device 19 to control the speed of the rotary snowplow 1.

〔effect〕

As described above, this invention detects the load condition of the snow-throwing engine, and further uses the actual speed of the rotary snowplow as input information to output the optimum snow-throwing speed and perform speed control. The speed of the snowplow can be controlled more accurately than before, improving the operability and maneuverability of the snowplow.

[Brief explanation of the drawing]

Fig. 1 is a block diagram of an automatic speed control device that is an embodiment of the present invention, Fig. 2 is an explanatory diagram of snow-throwing engine horsepower and snow-throwing volume, and Fig. 3 is an illustration of diesel engine engine speed and engine speed. Figure 4 is a characteristic diagram showing the snow throwing capacity limit of a rotary snowplow, Figure 5 is a diagram showing the relationship between optimal snow removal speed and snow removal amount, and Figure 6 is a diagram showing the relationship between the optimum snow removal speed and snow removal amount. FIG. 1 is a schematic configuration diagram of a car. In the figure, 10 is a load state detection means, 13 is a speed detection means, 14 is a load factor calculation means, 15 is a data memory means, and 17 is an optimum snow-throwing speed calculation means. In each figure, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Claims] 1 Load state detection means for detecting the load state of the snow throwing engine of the rotary snowplow; load factor calculation means for calculating the load factor based on the load state detected by the detection means; The smaller of the capacity limit based on the output and the capacity limit based on the snow throwing volume as a rotary snowplow is the snow throwing capacity limit of the snow throwing engine, and the load factor corresponding to this snow throwing capacity is the snow throwing capacity limit standard. Based on the outputs of the reference load factor data memory means for storing the reference load factor data memory means in the memory as a value, the speed detection means for detecting the actual speed of the rotary snowplow, the load factor calculation means, the reference load factor data memory means and the speed detection means. An automatic speed control device for a rotary snowplow, comprising: an optimum snow throwing speed calculating means for calculating an optimum snow throwing speed, and performing speed control using the output of the optimum snow throwing speed calculating means as a target speed.