JP3099172B2 - Liquid sprayer liquid spraying device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a liquid spraying device for a liquid spraying vehicle which sprays water or an antifreeze liquid on a road.

[0002]

2. Description of the Related Art In a liquid spraying device for a liquid spraying vehicle, the amount of sprayed liquid is automatically controlled so as to be synchronized with the running speed of the liquid spraying vehicle, so that the unit area is independent of the running speed of the liquid spraying vehicle. A device in which the amount of liquid sprayed per unit is made substantially constant is well known in the prior art (Japanese Utility Model Publication No. 2-2726).
No., Japanese Utility Model Publication No. 4-47217).

[0003]

In this type of liquid spraying device for a liquid spraying vehicle, the rotation speed and the vehicle speed of the spraying pump are detected, and the oil of the variable displacement hydraulic pump is detected based on the detected values. The discharge amount is steplessly increased / decreased, whereby the amount of liquid sprayed by the liquid spray pump is controlled to be synchronized with the vehicle speed via a constant displacement hydraulic motor.

In the above-mentioned conventional apparatus, the number of rotations of the watering pump is controlled by a command value calculated from the vehicle speed, and the number of rotations of the watering pump is detected and feedback-controlled, thereby accommodating fluctuations in the engine speed. Since the fluctuation of the number of rotations of the watering pump is prevented and the amount of watering per unit area is kept almost constant, there is a slight response delay in controlling the number of rotations of the watering pump due to the fluctuation of the engine rotation. There is a problem, and there is another problem that it becomes necessary to specially provide a rotation speed detecting means of the watering pump in addition to the vehicle speed detecting means, which increases the cost.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a novel liquid spraying device for a liquid spraying vehicle which solves the above-mentioned problems.

[0006]

Means for Solving the Problems] For the purpose achieved, coupled claimed according to the invention of claim 1, a variable displacement hydraulic pump and to be driven via the power take-off by run-row engine A hydraulic drive unit comprising a driven hydraulic motor; a liquid spray pump rotationally driven by the hydraulic motor; a vehicle speed detecting unit for detecting a traveling speed of the liquid spraying vehicle; and a rotation speed of a traveling engine of the liquid spraying vehicle. Based on the detected engine speed detecting means and the detection signals of the vehicle speed detecting means and the engine speed detecting means, the amount of liquid sprayed per unit area is made substantially constant regardless of the running speed of the liquid spraying vehicle. A control device for controlling the flow rate control means, wherein the control apparatus sends a control command value to be input to the flow rate control means to each detection signal of the vehicle speed detection means and the engine speed detection means. And a plurality of characteristic data respectively corresponding to a plurality of different virtual input / output characteristics of the flow control unit. 3. The storage apparatus according to claim 2 , further comprising: a storage unit; and a data switching unit that selectively uses any one of the plurality of characteristic data stored in the storage unit for calculation by the calculation unit. , in addition to the above structure of the invention of claim 1, wherein the hydraulic pump is more variable capacity swash plate type axial piston pumps pump discharge amount by the inclination angle change of the pump swash plate is changed, also the hydraulic motor fixed displacement Each of which comprises a swash plate type axial plunger motor, and wherein the flow rate control means further comprises a swash plate for angularly displacing the pump swash plate to a swash plate angle corresponding to a control command value input to the means. Composed of a corner control device.

[0007]

According to the above construction of the first aspect of the present invention , based on each detection signal of the vehicle speed detecting means and the engine speed detecting means,
And per unit area regardless of the running speed of the liquid sprayer
The flow rate control means so that the amount of sprayed liquid is almost constant
Therefore, it is possible to directly detect the rotation fluctuation of the driving engine, particularly in the low rotation range where the fluctuation width is large, and further, it is not necessary to perform the feedback control by detecting the rotation speed of the conventional liquid spray pump. The responsiveness of the liquid pump control can be greatly improved.

[0008] On of their, even if there are variations in the output characteristics of the flow control means incorporated in the actual vehicle, optionally with the data switching means, corresponding to approximate the actual input-output characteristic property storage Since data can be selected from the storage unit and used for the control command value calculation of the calculation means,
An error in the amount of spraying caused by a variation in the input / output characteristics of the individual flow control means is suppressed as much as possible, and the error can be kept within a predetermined allowable error range.

[0009]

EXAMPLES Hereinafter, proposed by the present inventor with reference to Figures 1-7
The liquid sprayer will be described. Figure 1 is a whole schematic side view of a liquid body spraying vehicles, FIG. 2 is an overall schematic configuration diagram of a liquid spraying device, in these figures, the water on the road, a liquid for spraying a chemical solution or the like for antifreeze Spreader V is its chassis F
A liquid tank T is mounted thereon, and an operator's cab C is provided in front of a chassis F. A traveling engine 1 is suspended from a chassis F below a cab C. An output shaft 3 extends rearward from a transmission 2 at a rear end of the engine 1, and the output shaft 3 is connected to a parking brake 4 and a joint 5.
The rear end of the propeller shaft 6 is connected to the left and right rear wheels 8 via a differential device 7, and the left and right rear wheels 8 are driven by the operation of the engine 1 as usual. The liquid sprayer V runs.

A spray pump Pf for spraying the liquid stored in the liquid tank T on the road is driven and controlled by the traveling engine 1 via a hydraulic drive unit Do described later. A power take-off device (flywheel PTO) 9 is provided on the flywheel of the traveling engine 1.
Is connected. The output end of the power take-off device 9 is connected to the input end of the hydraulic drive means Do via a joint 25, a transmission shaft 26 having a spline expansion / contraction part, and another joint 27, and the output end of the hydraulic drive means Do Is connected to the pump shaft of the spray pump Pf.

The hydraulic drive means Do is constituted by a combination of a variable displacement hydraulic pump Po and a constant displacement hydraulic motor Mo. The hydraulic pump Po is a variable displacement swash plate type axial plunger pump, The hydraulic motor Mo is a constant displacement swash plate type axial plunger motor, and the oil discharge amount is steplessly increased and decreased by controlling the inclination angle of the swash plate 10 of the hydraulic pump Po. Are continuously and continuously controlled. As the hydraulic pump Do and the hydraulic drive means Do composed of the hydraulic motor Mo, conventionally known ones are employed, and detailed description thereof will be omitted.

The suction side of the spray pump Pf is a suction circuit 1
1 and connected to the outlet of the liquid tank T, and the discharge side thereof is connected to the liquid spray circuit 12. The liquid spray circuit 12 extends along the front-rear direction of the chassis F, and an appropriate liquid spray nozzle 13 is connected thereto. And the spray pump Pf
According to the drive of, the stored liquid such as water in the liquid tank T can be sprayed on the road from the spray nozzle 13.

The number of revolutions of the spraying pump Pf is automatically controlled to increase or decrease according to the running speed of the liquid spraying vehicle V, and the spraying amount of the liquid spraying vehicle V is synchronized with the running speed to spray the liquid per unit area. The amount can be controlled to be substantially constant, and the control system will be described below.

The traveling drive system of the liquid sprinkling vehicle V is provided with vehicle speed detecting means Dv for detecting the vehicle speed.
Next, the vehicle speed detecting means Dv will be described with reference to FIGS. 2 and 3 and 4. FIG. 3 is an enlarged view of a portion 3 in FIG. 1, and FIG. 4 is a line 4-4 in FIG. FIG. In these drawings, wherein the outer surface of the rotary unit 4 ₁ of the parking brake 4, detector 15 made of a magnetic material such as a steel plate is bolted 16. Detector 15 ₁ of the detector 15 extends in a radial direction of the rotary unit 4 _1, The detector 15 _1, the proximity switch 17 is oppositely arranged with a predetermined gap therebetween (5 to 10 mm) . This proximity switch 1
Reference numeral 7 denotes a rotating member 4 of the parking brake 4 which is supported by a cross member 18 of a chassis F via a bracket 19.
The rotation of ₁ causes the detection body 15 to move its proximity switch 17
Each time the detection object 1 is detected, a change in the electric resonance is detected and converted into an electric pulse signal, and the speed of the liquid spraying vehicle V can be detected by the pulse signal.
5 and the proximity switch 17 constitute a vehicle speed detecting means Dv.

On the other hand, a power take-out system connecting the power take-out device 9 and the hydraulic pump Po is provided with an engine speed detecting means Dr for detecting the speed of the traveling engine 1.

The structure of the detecting means Dr will be described below with reference to FIG.
5 will be described with reference to FIGS. 5 and 6. FIG.
6 is a partial view along line 6-6 in FIG. 5. In these figures, a catch plate 28 is provided at a connecting portion between the transmission shaft 26 and the input end of the hydraulic pump Po. A detection body 29 made of a magnetic material such as an iron plate is fixed to the catch plate 28. This detector 2
Reference numeral 9 extends in the radial direction of the catch plate 28, and a proximity switch 30 is provided opposite to the detection body 29 at a predetermined interval (5 to 10 mm). This proximity switch 3
Numeral 0 is supported by a stay 31 fixed to the chassis F via a bracket 32. The rotation of the catch plate 28 causes the detector 29 to detect a change in electrical resonance each time the detector 29 faces the proximity switch 30. This is converted into an electric pulse signal, and the number of revolutions of the traveling engine 1 can be detected based on the pulse signal.
Is configured.

FIG. 7 is a block diagram showing a sprinkling control system. In this figure, the detection signals from the vehicle speed detecting means Dv and the engine speed detecting means Dr are all provided by the sprinkling control means provided in the cab C. Sent to Cr. In the sprinkling control means Cr, the two detection values are compared and calculated in the arithmetic processing circuit 21, and the output signal from the arithmetic processing circuit 21 is transmitted to the flow control means Cf of the hydraulic pump Po via the command output circuit 22. The control signal is a hydraulic motor to change control the inclination angle of the swash plate 10 by operating the swash plate operating mechanism 10 ₁ of the hydraulic pump Po Mo from the flow control means Cf
The number of revolutions of the sprayer P is steplessly increased and decreased, whereby the discharge amount of the spray pump Pf can be increased and decreased. Specifically, the speed of the liquid spraying vehicle V increases and the spraying amount per unit area decreases. If there is a tendency, the hydraulic pump Mo is controlled by controlling the hydraulic pump Po while taking into account the rotational speed of the traveling engine 1 at that time.
The number of revolutions of the spraying pump Pf is automatically increased, and if the speed of the liquid spraying vehicle V decreases and the amount of spraying per unit area tends to increase, the traveling engine at that time is increased. By controlling the hydraulic pump Po while considering the number of rotations of 1, the number of rotations of the hydraulic motor Mo can be reduced, and the spray flow rate of the spray pump Pf can be automatically reduced.

[0018] Then the real施例of the present invention will be described with reference to FIG. The basic structure of the liquid spray vehicles the actual施例is Figure
It is the same as the liquid spray vehicles described by 1-7, not described, in the following description only configuration of the pump displacement control system which is a feature of the actual施例(Note, using 8 each The reference numerals of the components have been described with reference to FIGS.
The reference numerals of the corresponding components of the liquid sprayer are used as they are).

[0019] Thus to this real施例is the discharge rate of the hydraulic pump Po as a flow rate control means for variably controlling a known electric swash plate angle control unit EDC is used. The control device EDC includes, for example, a pilot valve that outputs a pilot pressure proportional to a command electric signal (hereinafter, referred to as a control command value i) input to the device, and a swash plate angle of a double spool structure that responds to the pilot pressure. The control command value i (input) is provided by interlocking the swash plate angle control valve with the pump swash plate 10 via a link mechanism.
The pump swash plate 10 can be accurately angularly displaced to an inclination angle θ (output) corresponding to the above.

In this embodiment, the sprinkling control means Cr comprises:
A function as a control device according to the invention of claim 2, wherein the flow rate control means (that is, the swash plate angle control device EDC) is controlled so that the amount of liquid sprayed per unit area is substantially constant regardless of the traveling speed of the liquid spraying vehicle V. The vehicle speed detecting means D
v and input means I for inputting each detection signal from the engine speed detection means Dr, and arithmetic means A for calculating the control command value i based on each of the detection signals input to the input means I. An output means O for outputting the control command value i to the swash plate angle control device EDC based on the calculation result of the calculation means A, and a swash plate angle control device EDC to be taken into account in the calculation in the calculation means A. Storage means M for preliminarily storing characteristic data corresponding to the input / output characteristics. For example, a microcomputer is used as the sprinkling control means Cr, and its central processing unit (CP)
U) is used as the arithmetic means A, and a memory inside or outside the central processing unit is used as the storage means M.

In the calculation means A, when the calculation is performed, the vehicle speed detection means Dv is controlled so that the amount of sprayed liquid per unit area is substantially constant irrespective of the running speed of the liquid spraying vehicle V.
And a formula for determining the target discharge amount of the hydraulic pump Po (that is, the tilt angle θ of the pump swash plate 10) from each detection signal from the engine speed detecting means Dr, and a formula showing the input / output characteristics of the swash plate angle control device EDC. (That is, a control command value i as an input,
A control command value calculation formula derived from the relationship between the output angle and the tilt angle θ of the pump swash plate 10 is used. In this embodiment, the control command value calculation formula corresponds to the input / output characteristics of the EDC. Stored as the characteristic data in the storage means M,
It is memorized.

Since the actual input / output characteristics Xr of the swash plate angle control device EDC are non-linear as illustrated in FIG.
If this is approximated by only one relational expression corresponding to a single straight line x, the error becomes too large. In order to reduce the error, the input / output characteristic curve is divided into a plurality of (for example, four) straight lines as illustrated in FIG. 10 and a plurality of relational expressions respectively corresponding to the plurality of straight lines x _{1 to} x ₄ are obtained. It is desirable to approximate the input / output characteristics by using a plurality of relational expressions (hereinafter, referred to as divisional relational expressions).

However, when an actual vehicle test was conducted using such a division relational expression, the input / output characteristics Xr of the individual swash plate angle control devices EDC showed in FIGS. It has been found that there is a variation range Y in a predetermined range as shown in FIG. For this reason, only the characteristic data (control command value calculation formula) corresponding to only one approximate input / output characteristic X of the swash plate angle control device EDC is stored in the storage means M,
If the calculating means A calculates the control command value i on the basis of the data, the above-mentioned variation is directly applied to the pump swash plate 10.
There is a possibility that this may cause a tilt angle error, and eventually cause a decrease in accuracy of the amount of sprayed liquid.

Therefore, in this embodiment, the storage means M
In addition, a plurality of characteristic data respectively corresponding to a plurality of virtual input / output characteristics X, X ', X "different in the variation area Y (that is, the plurality of characteristic data corresponding to the respective input / output characteristics X, X', X"). Control command value calculation formula obtained by taking into account the division relation formula)
And a storage unit m for storing and storing
In this case, the plurality of virtual input / output characteristics X, X ', X "
Is obtained by zero adjustment and inclination adjustment of each of the division relational expressions. The sprinkling control means Cr has a storage unit m
A data switching means S such as a changeover switch for selectively using any one of the plurality of characteristic data stored and stored in the arithmetic means A, and an operation unit n of the data switching means S Is installed on an appropriate part which can be manually operated at any time but can be understood only by a specific person such as a service person, for example, a control panel of the liquid spraying control means Cr. There is no danger.

Thus, even if the input / output characteristics of the individual swash plate angle control devices EDC incorporated in the actual vehicle vary, the degree of the variation is actually measured, and the data switching means S is used as necessary. Since it is possible to select the storage data (that is, the control command value calculation formula) corresponding to the characteristics similar to the actual input / output characteristics from the storage unit m and use the selected data for the control command value calculation of the calculation unit A, Swash plate angle controller EDC
It is possible to minimize the error of the spray amount caused by the variation in the input / output characteristics and to keep the error within a predetermined allowable error range, so that the accuracy of the spray amount can be further improved. still,
If such a data switching operation is completed in advance before the actual vehicle is shipped from the production factory, a vehicle having a high accuracy of the amount of sprayed liquid can be stably shipped. Further, even if the input / output characteristics of the swash plate angle control device EDC change over time after the shipment, the data switching operation can be performed depending on the degree of the change.

Although the embodiments of the present invention have been described above, the present invention is not limited to the embodiments, and various embodiments are possible within the scope of the present invention. For example, in the above-described embodiment, the engine speed detection means is provided at the connection between the transmission shaft and the input end of the hydraulic pump. However, this may be provided anywhere in the transmission system connecting the engine and the hydraulic pump.
Further, as the engine speed detecting means, a conventionally known one can be used. Also, instead of providing the detection body of the vehicle speed detection means on the parking brake,
It may be provided on a rotating part such as a propeller shaft or an axle. Further, as a vehicle speed detecting means, a conventionally known one such as a speedometer rotating cable can be used.

[0027]

As described above, according to the present invention, in a liquid spraying device for a liquid spraying vehicle, a vehicle speed detecting means and an engine are provided.
Based on each detection signal of the rotation speed detection means,
Spray volume per unit area almost constant regardless of running speed
And controls the flow rate control means so as to, rotation fluctuation of the running engine, in particular can be directly detecting the rotation fluctuation of a large low rotation speed region of the fluctuation range, Furthermore, the rotation of the conventional dispersion liquid pump Feedback control by number detection becomes unnecessary, and the responsiveness of the spray pump control can be greatly improved. Further, as the engine speed detecting means, it is possible to use an existing engine speed detecting means used for normal control such as idle-up control of the engine itself, air conditioner control, automatic shift control, antilock control and the like. Thus, the cost of the entire apparatus can be reduced.

In particular, the control device for controlling the flow rate control means determines a control command value to be input to the flow rate control means based on each detection signal of the vehicle speed detection means and the engine speed detection means, and controls the input / output of the flow rate control means. A calculating means for calculating in consideration of the characteristic; a storage means for storing a plurality of characteristic data respectively corresponding to a plurality of different virtual input / output characteristics of the flow control means; and the storage means stored in the storage means. because and a data switching means for selectively using one of a plurality of characteristic data for the calculation of the calculation means, even if there are variations in the output characteristics of the flow control means incorporated in the actual vehicle, optionally By using the data switching means, storage data having characteristics similar to actual input / output characteristics can be selected from the storage unit and used for control command value calculation of the calculation means. Of from the flow control unit error of minimizing and application rate caused by variations in the input-output characteristic of making it possible to fall within a predetermined allowable error range, it is possible to further improve the dispersion liquid of accuracy.

[Brief description of the drawings]

FIG. 1 is a whole schematic side view of a liquid body spraying vehicles

FIG. 2 is an overall schematic configuration diagram of a liquid spraying device .

FIG. 3 is an enlarged view of three parts in FIG. 1;

FIG. 4 is a sectional view taken along line 4-4 in FIG. 3;

FIG. 5 is an enlarged view of five parts in FIG. 1;

FIG. 6 is a sectional view taken along the line 6-6 in FIG. 5;

FIG. 7 is a block diagram showing a sprinkling control system.

8 is a block diagram showing a control system of the real施例of the present invention

FIG. 9 is a graph showing the input / output characteristics of the swash plate angle control device (ie, the relationship between the control command value i and the swash plate angle θ).

FIG. 10 is a graph similar to FIG. 9, showing a plurality of virtual input / output characteristics of the swash plate angle control device;

[Explanation of symbols]

1 ... Engine 9 ... Power take-off device 10 ... Pump swash plate A ... Calculation means Cf ... Flow control means Cr ... Sprinkling control means as a control device Do ... Hydraulic drive means Dr ... Engine rotation speed detection means Dv ... Vehicle speed detection means EDC ... Swash plate as flow rate control means Swash plate angle control device M: Storage unit Mo: Hydraulic motor Pf Sprinkling pump Po: Variable displacement hydraulic pump S: Data switching Means V: Liquid sprayer θ: Inclination angle of swash plate

Continuation of the front page (56) References JP-A-61-141954 (JP, A) JP 4-47217 (JP, Y2) (58) Fields investigated (Int. Cl. ⁷ , DB name) E01H 3 / 02 E01H 10/00 E01C 19/16

Claims (2)

(57) [Claims] 1. A run variable displacement hydraulic pump driven via the power take-off (9) by a row engine (1) (P
o) and a hydraulic drive means (Do) comprising a hydraulic motor (Mo) connected to the pump (Po) and rotationally driven;
The dispersion liquid and a pump (Pf) which is rotated by a hydraulic motor (M o), and vehicle speed detecting means for detecting a running speed of the liquid spray vehicles (V) (Dv), the running engine of the liquid spray vehicles (V) (1) an engine rotational speed detecting means (Dr) for detecting the rotational speed, a flow control means (EDC) for variably controlling the discharge amount of the variable displacement hydraulic pump (Po), and the vehicle speed detecting means (Dv). And engine speed detecting means (D
r) a control device (Cr) for controlling the flow rate control means (EDC) based on each of the detection signals so as to make the amount of sprayed liquid per unit area substantially constant irrespective of the traveling speed of the liquid sprayer (V). The control device (Cr) includes the flow rate control means (EDC).
The control command value (i) to be input to the vehicle speed detection means (D
v) calculating means (A) for calculating based on each detection signal of the engine speed detecting means (Dr) and taking into account the input / output characteristics of the flow rate controlling means (EDC); and the flow rate controlling means ( Storage means (M) for storing a plurality of characteristic data respectively corresponding to a plurality of different virtual input / output characteristics (X, X ', X ") of the EDC, and the storage means (M). operation in and having a data switching means for selectively utilizing (S), the liquid spraying equipment for liquid spraying vehicle wherein said calculating means any of a plurality of characteristic data (a). 2. The hydraulic pump according to claim 1, further comprising a pump swash plate.
The variable displacement type swash plate type axial plunger pump (Po) in which the pump discharge amount changes according to the inclination angle change, and the hydraulic motor is constituted by a constant displacement type swash plate type axial plunger motor (Mo). Comprises a swash plate angle control device (EDC) for angularly displacing the pump swash plate (10) to an inclination angle (θ) corresponding to a control command value (i) input to the means. The liquid spraying device for a liquid spraying vehicle according to claim 1 , wherein: