JPH0427914B2 - - Google Patents

Description

Detailed Description of the Invention (Industrial Application Field) The present invention is an improvement of a spray amount control device for a liquid spray vehicle that automatically sprays water, anti-freezing chemicals, etc. onto roads using a spray pump. Regarding.

(Prior art) Generally, when this type of liquid spray vehicle automatically sprays water, antifreeze chemicals, etc. onto a road, the amount of liquid sprayed from the spray pump is a predetermined amount per unit area anywhere on the road. Road cleaning to be uniform,
Desirable for accident prevention. In other words, the amount of liquid sprayed from the liquid spray pump is synchronized with the vehicle speed, and the amount of liquid sprayed increases at high vehicle speeds where the spray area per unit time becomes wider, while at low vehicle speeds where the spray area per unit time becomes smaller. Preferably, the amount is reduced.

However, when the liquid spray pump is simply connected directly to the vehicle's driving engine, the rotational speed of the driving engine (that is, the amount of liquid sprayed) does not correspond to the vehicle speed, and the relationship is selected by the driver. Since it differs depending on the gear position of the transmission, the amount of liquid sprayed per unit area changes depending on the gear position of the transmission even at the same engine speed.

Therefore, conventionally, for example, in the method disclosed in Japanese Patent Application Laid-Open No. 57-113861, a liquid spraying engine is provided separately from the driving engine of the vehicle, and a liquid spraying pump is driven by the liquid spraying engine. At the same time, by controlling the rotational speed of the liquid spraying engine so that its rotation speed is synchronized with the vehicle speed, the amount of liquid sprayed from the liquid spray pump is synchronized with the vehicle speed, and the amount of liquid sprayed per unit area is maintained at a predetermined value. It is made to be.

(Problems to be Solved by the Invention) However, in the above-mentioned conventional system, two engines are mounted on one vehicle due to the addition of a liquid spraying engine to a driving engine. The disadvantages were that the quietness and fuel efficiency of the system decreased, and the overall size of the device increased. Moreover, the range in which the rotation speed of the liquid spraying engine should be controlled is wide-ranging and corresponds to the range of changes in vehicle speed. When setting various vehicle speed synchronization characteristics of the rotation speed of the liquid spraying engine so that it can be increased and changed depending on the difference in the liquid spray width, etc., the rotation speed control range to be expanded is The rotational speed variable range may be exceeded, and as a result, the degree of freedom for various settings of vehicle speed tuning characteristics is small, and the liquid dispersion performance cannot be effectively exhibited.

The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to directly drive the above-mentioned liquid spray pump at a predetermined gear ratio by a driving engine, and to change the speed for driving the liquid spray pump. By controlling the ratio so that the pump rotation speed is synchronized with the vehicle speed, the amount of liquid sprayed can be synchronized with the vehicle speed without requiring a liquid spraying engine as described above.
In addition to improving vehicle quietness and fuel efficiency and making the equipment more compact, the amount of liquid sprayed from the spray pump basically increases or decreases depending on changes in vehicle speed, so The object of the present invention is to make it possible to reduce the control range of the gear ratio with respect to the rotational speed of the pump, and to make it possible to set various vehicle speed synchronization characteristics with a large degree of freedom.

(Means for Solving the Problems) In order to achieve the above object, as shown in FIG. , a hydraulic transmission mechanism 14 having a set of liquid circulation circuits 18 consisting of a variable displacement hydraulic pump 15 and a hydraulic motor 17; and a hydraulic transmission mechanism 14 that is drivingly connected to the hydraulic transmission mechanism 14 and discharges a predetermined liquid onto the road. A vehicle speed detecting means 20 detecting the vehicle speed, a pump rotation speed detecting means 21 detecting the rotation speed of the liquid spray pump 3, and detection signals of both the detecting means 20, 21. In response to this, the present invention is configured to include a control means 22 for controlling the discharge amount of the variable displacement hydraulic pump 15 of the hydraulic transmission mechanism 14 so that the rotational speed of the liquid spray pump is synchronized with the vehicle speed with predetermined characteristics. .

(Function) As described above, in the present invention, while the liquid spray pump 3 is directly rotationally driven by the driving engine 10, the liquid spray pump 3 is driven by the driving engine 10.
By changing the speed of the rotary drive in synchronization with the vehicle speed by the hydraulic transmission mechanism 14, the amount of liquid sprayed is synchronized with the vehicle speed without the need for a conventional liquid spraying engine, and the amount of liquid sprayed per unit area is increased. The amount is maintained at a predetermined amount regardless of vehicle speed. Moreover, the liquid spray pump 3 is powered by the traveling engine 10.
Basically, the amount of liquid sprayed follows the change in vehicle speed due to the direct drive of the hydraulic transmission mechanism 14.
Since the shift control range of the hydraulic transmission mechanism 14 is expanded within the variable shift range to set various vehicle speed synchronization characteristics, it is possible to easily expand the shift control range of the hydraulic transmission mechanism 14 to set various vehicle speed synchronization characteristics. The degree of freedom increases.

(Example) Hereinafter, an example of the present invention will be described in detail based on the drawings from FIG. 2 onwards.

FIG. 2 shows an embodiment in which the present invention is applied to a water sprinkler vehicle. In the water sprinkler truck A shown in the figure, 1 is a chassis, 2 is a water tank that is placed and fixed on the chassis 1 and stores water for watering inside, and 3 is a water outlet provided at the lower front end of the water tank 2. The turbine pump serves as a sprinkler pump that pumps and discharges water supplied from 2a via a water pipe 4, and the turbine pump 3 has a water spray nozzle 6 provided on the side of the vehicle chassis 1 via a water pipe 5. The water in the water tank 2 is discharged and sprayed onto the road from the water spray nozzle 6 by the rotational drive of the turbine pump 3.

Next, FIG. 3 shows the overall configuration of a drive control system for the turbine pump 3 for adjusting the amount of water sprayed from the water spray nozzle 6. In the figure, reference numeral 10 denotes a driving engine mounted on the water sprinkler A shown in FIG. It is connected to the.

Reference numeral 14 denotes a hydraulic transmission mechanism which is important in the configuration of the present invention and is drivingly connected to the driving engine 10, and the hydraulic transmission mechanism 14 is a variable displacement type transmission mechanism which is drivingly connected to the driving engine 10. A hydraulic pump 15 and two liquid pipes 1 to the hydraulic pump 15.
It has a set of liquid circulation circuits 18 including a hydraulic motor 17 connected to the liquid circulation circuits 6 and 16 so as to be able to circulate the liquid. The variable displacement hydraulic pump 15
has a swash plate 15a that is positioned in a neutral state when not in operation, and a discharge amount control section 15b that controls the inclination of the swash plate 15a to an angle according to the magnitude of an input signal from a controller 22, which will be described later. .
Further, the turbine pump 3 is drivingly connected to the hydraulic motor 17, and the liquid discharge amount is increased or decreased by controlling the inclination of the swash plate 15a of the variable displacement hydraulic pump 15, that is, by controlling the discharge amount. By controlling the rotation speed of the motor 17, the rotation speed of the turbine pump 3, that is, the amount of water sprayed from the water spray nozzle 6, is increased or decreased.

Furthermore, a vehicle speed sensor 20 serves as vehicle speed detection means for detecting vehicle speed based on the rotational speed of the propulsion shaft 12;
Reference numeral 1 denotes a pump rotation speed sensor as pump rotation speed detection means for detecting the rotation speed of the turbine pump 3 based on the rotation speed of the output shaft 17a of the hydraulic motor 17, and the output signals of the sensors 20 and 21 are controlled respectively. A control signal is input to a control unit 22 as a means, and the control unit 22 inputs a control signal to the discharge amount control section 15b of the variable displacement hydraulic pump 15, thereby controlling the tilt of the swash plate 15a.

Next, the operation of the control unit 22 will be explained with reference to FIG. 25 is an F/V converter that converts the vehicle speed signal from the vehicle speed sensor 20 into frequency-voltage; 26 is the vehicle speed signal V from the F/V converter 25;
and a watering start vehicle speed _V0 signal from a watering start vehicle speed adjustment knob 27, and zero-adjusts the vehicle speed signal V to a signal V' with the watering start vehicle speed _V0 as a reference (zero point); is a first map that stores in advance a total of six types of target rotational speed N characteristics of the turbine pump 3 relative to the vehicle speed V, according to the road width to be watered, that is, one lane and two lanes, and according to the solvent mixed in the water in the water tank 2. In response to the vehicle speed V' signal from the watering start vehicle speed setting circuit 26, and the vehicle speed V', the one-lane signal or the two-lane signal from the lane selection switch 29, and the solvent selection signal from the solvent selection switch 30, The target rotation speed N of the turbine pump 3 is calculated. Also, 3
1 receives the target rotation speed N signal from the first map 28 and the minimum rotation speed N _MIN signal of the turbine pump 3 from the pump minimum rotation speed adjustment knob 32, and determines that N<
Set the target rotation speed N to the minimum rotation speed N _MIN within the range of N _MIN
A minimum rotation speed regulation circuit 33 compares the target rotation speed N from the minimum rotation speed regulation circuit 31 with the maximum rotation speed N _MAX from the maximum rotation speed adjustment knob 34, and determines the range of N>N _MAX . Target rotation speed N within
This is a maximum rotation speed regulation circuit that replaces N MAX with the maximum rotation speed N _MAX .

Further, 35 is a control handle for manually setting the rotation speed of the turbine pump 3, that is, the water sprinkling amount, and 36 is the control handle 3.
The manual target rotation speed setting circuit 36 is a manual target rotation speed setting circuit that sets the target rotation speed N' of the turbine pump 3 according to the manual operation amount of step 5, and the manual target rotation speed setting circuit 36 includes a minimum rotation speed regulation circuit 37 similar to the above. and a maximum rotation speed regulation circuit 38 are attached.

Furthermore, 40 is an automatic/manual changeover switch for manually selecting between automatic and manual setting of watering amount, and when switching to the automatic side, the maximum rotation speed regulation circuit 3
Select the target rotation speed N from 3, and when switching to the manual side, select the target rotation speed of the manual target rotation speed setting circuit 36.
It is provided to select N′. Automatic/
A feedback control circuit 42 for feedback controlling the rotation speed of the turbine pump 3 is connected to the manual changeover switch 40 via a delay circuit 41 of, for example, 1 second. receives the turbine pump rotational speed N _T signal from the F/V converter 43, and compares the turbine pump rotational speed N _T with the target rotational speed N or N' from the automatic/manual changeover switch 40. , its deviation N _T −N or N _T −
Integral value I (0.5 to 10 seconds) and proportional value P (0.1 to 10) as control gain value of feedback control according to N'
is calculated, and the rotation speed N _T of the turbine pump 3 is feedback-controlled based on the respective control gain values I and P. The output signal from the feedback control circuit 42 is input to the discharge amount control section 15b of the variable displacement hydraulic pump 15 via the current control amplifier 44 which converts the signal into a current value according to the magnitude of the output signal. The swash plate 15a is positioned at an inclination angle corresponding to the target rotational speed N or N' to control the discharge amount. still,
In FIG. 4, 50 connects the target rotational speed N or N' signal from the automatic/manual changeover switch 40 and the turbine pump rotational speed N _T signal from the pump rotational speed sensor 21 via a delay circuit 51 of 0.5 to 5 seconds. The deviation abnormality stop circuit outputs a forced stop signal when the deviation between both signals is equal to or greater than a predetermined value corresponding to an abnormality, and the forced stop signal causes the current control amplifier 44 to output a forced stop signal to the variable displacement hydraulic pump 15. A relay 52 interposed in the signal input circuit to the discharge amount control section 15b of
By opening the swash plate 15a, the input of the signal to the variable displacement hydraulic pump 15 is forcibly stopped, and the swash plate 15a is positioned approximately in the neutral position. Further, 53 is a pump high-speed rotation alarm circuit that outputs an acoustic signal and sounds a buzzer 54 when the pump rotation speed N _T from the pump rotation speed sensor 21 reaches a predetermined high rotation speed, and 55 is a turbine pump 3 is a tachometer that digitally displays the pump rotation speed N _T every 10 rpm, 56 is a control handle 35
Handle operation detection switch that opens when in neutral position,
57 is a manual control indicator light that lights up when the handle operation detection switch 56 is closed. Furthermore, 58
Reference numeral 59 denotes an on-vehicle battery, and 59 a voltage regulator that adjusts the voltage supplied from the on-vehicle battery 58 to the control unit 22 to a predetermined value.

Therefore, in the above embodiment, at the same time as the driving engine 10 rotationally drives the drive wheels 13 and the water truck A runs, the power of the driving engine 10 is transmitted to the turbine pump 3 via the hydraulic transmission mechanism 14. As a result, the turbine pump 3 is rotationally driven, and the water in the water tank 2 is discharged and sprayed onto the road from the water spray nozzle 6.

At this time, when the automatic/manual changeover switch 40 is switched to the automatic side, the target rotation speed N of the turbine pump 3 is determined in the first map 28 according to the vehicle speed signal from the vehicle speed sensor 20 in the control unit 22, and this target rotation speed When the pump rotation speed N _T from the pump rotation speed sensor 21 is higher than the number N, the variable displacement hydraulic pump 1 of the hydraulic transmission mechanism 14
As the swash plate 15a of No. 5 is feedback-controlled to the neutral side and the pump rotation speed N _T falls, the amount of water sprayed from the water nozzle 6 decreases, but when the pump rotation speed N _T is lower than the target rotation speed N. ,
Conversely, as the swash plate 15a of the variable displacement hydraulic pump 15 is greatly tilted and the pump rotation speed N _T increases, the amount of water sprayed from the water nozzle 6 increases repeatedly, and the amount of water sprayed reaches the target rotation. It converges to a predetermined value depending on the number N. By repeating the above operation every time the vehicle speed changes, the amount of water sprayed from the water nozzle 6 synchronizes with the vehicle speed due to the characteristics of the first map 28, and increases at high vehicle speeds when the spray area becomes wider. On the other hand, it decreases at low vehicle speeds when the spray area becomes narrower, and as a result, the spray amount per unit area is maintained at a predetermined value. Then,
Since the amount of water sprinkled per unit area can be maintained at a predetermined value without requiring a conventional liquid spraying engine, it is possible to improve the quietness of the vehicle, improve fuel efficiency, and make the device more compact.

Moreover, by directly driving the turbine pump 3 by the driving engine, the amount of water sprayed from the water nozzle 6 basically increases or decreases according to changes in vehicle speed, and the variable capacity of the hydraulic transmission mechanism 14 increases or decreases accordingly. The tilt control range of the swash plate 15a of the hydraulic pump 15 can be small. As a result, the tilt control range of the swash plate 15a has a margin with respect to the variable control range of the swash plate 15a, so even when the vehicle speed synchronization characteristics are variously set as shown in the first map 28, the tilt control range of the swash plate 15a is This can be easily expanded within the variable control range and can be performed with a large degree of freedom, thereby improving water sprinkling performance.

Incidentally, in the above embodiment, a case where the present invention is applied to a water sprinkler vehicle has been described, but the present invention is not limited thereto, and it goes without saying that it can be similarly applied to a liquid spraying vehicle that sprays anti-freeze chemical liquid or the like.

(Effects of the Invention) As explained above, according to the present invention, the liquid spray pump is directly driven by the driving engine via the hydraulic transmission mechanism, and the hydraulic transmission mechanism is controlled by the hydraulic transmission mechanism. By controlling the rotation speed to synchronize with the vehicle speed, it is possible to synchronize the liquid spray amount with the vehicle speed without requiring a separate engine for liquid spraying and while ensuring a large degree of freedom in vehicle speed synchronization characteristics. It is possible to improve the quietness and fuel efficiency of the system, make the device more compact, and also improve the liquid spraying performance.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the configuration of the present invention. Figures 2 to 5 show embodiments of the present invention, Figure 2 is a side view showing a schematic configuration of a water sprinkler truck, Figure 3 is a diagram showing the overall configuration of a water sprinkler amount control system, and Figure 4 is a control system. Block diagram showing the operation flow of the unit, No. 5
The figure is a specific electrical circuit diagram showing the internal configuration of the control unit. 3... Turbine pump, 6... Water nozzle, 1
0...Travel engine, 14...Hydraulic pressure transmission mechanism, 15...Variable displacement hydraulic pump, 17...Hydraulic pressure motor, 18...Liquid circulation circuit, 20...Vehicle speed sensor, 21...Pump rotation Several sensors, 22... control unit.

Claims (1)

[Claims] 1 A hydraulic transmission mechanism 14 having a driving engine 10 mounted on a vehicle and a set of liquid circulation circuits 18 driven by the driving engine 10 and consisting of a variable displacement hydraulic pump 15 and a hydraulic motor 17.
and a liquid spray pump 3 which is drivingly connected to the hydraulic transmission mechanism 14 and discharges and sprays a predetermined liquid onto the road, and a vehicle speed detecting means 2 which detects the vehicle speed.
0, a pump rotation speed detection means 21 for detecting the rotation speed of the liquid dispersion pump 3, and both detection means 20, 2.
1, the control means 22 controls the discharge amount of the variable displacement hydraulic pump 15 of the hydraulic transmission mechanism 14 so that the rotational speed of the liquid spray pump is synchronized with the vehicle speed according to a predetermined characteristic. A spray amount control device for a liquid spray vehicle featuring: