JP2002187477A - Drive controlling device for mixer drum - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a drive controlling device for a mixer drum capable of improving traveling stability of a vehicle. SOLUTION: This device comprises a mixer drum 1 which is rotatably loaded on the vehicle, a driving device which comprises a variable displacement pump 3 rotating the mixer drum 1 in a forward and reverse direction at a increasing and decreasing speed and capable of adjusting discharge capacity and a motor 4, a traveling engine 2 for rotating the driving device at the increasing and decreasing speed, a means for commanding speed at the time of transportation which produces a target drum rotation speed according to a rotation speed Ne at the time of traveling of the traveling engine 2, and a means which calculates a capacity Dp of the variable displacement pump 3 required for the target drum rotation speed from a capacity Dm of the motor 4 and the rotation speed Ne of the traveling engine 2 and controls a pump capacity for controlling the capacity Dp of the variable displacement pump 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a concrete mixer vehicle, and more particularly to a mixer drum drive control device for a concrete mixer vehicle suitable for controlling a drum rotation speed during running of the vehicle.

[0002]

2. Description of the Related Art In a concrete mixer truck, even during traveling, the mixer drum is rotated to mix the ready-mixed concrete charged into the drum until it arrives at a destination / construction site, and the drum is reversed at the construction site to perform kneading. The raw concrete that has risen is discharged.

[0003] The drum driving device includes a variable displacement pump driven by a traveling engine and a motor for rotating the drum by a fluid discharged from the variable displacement pump. Controlling speed.

[0004] When the ready-mixed concrete is conveyed, only the feedback control of the displacement of the variable displacement pump corresponding to the deviation between the drum rotation speed and the target drum rotation speed can respond to a change in the engine rotation speed during the traveling. Paying attention to the occurrence of a delay, a mixer drum drive control device that prevents the drum rotation speed from greatly deviating from the target drum rotation speed even with a change in the rotation speed of the traveling engine is disclosed in, for example, JP-A-3-29617. Some are described in the gazette.

This drum drive control device obtains a deviation between the rotation speed of the motor or the drum and a preset target drum rotation speed, and superimposes a value corresponding to an increase / decrease value of the engine rotation speed from the reference rotation speed on the deviation. By correcting the deviation signal between the motor rotation speed and the target drum rotation speed, the displacement of the variable displacement pump is controlled based on the corrected signal, and the drum rotation speed is controlled to the target drum rotation speed. I have.

[0006]

However, in the above-mentioned prior art, the target drum rotational speed is set to a predetermined value irrespective of the engine rotational speed, so that a drum driving load that fluctuates regardless of the running load is applied to the engine. However, there is a problem that the running stability of the vehicle is hindered.

[0007] In particular, the weight of the drum filled with ready-mixed concrete
When controlling a rotating body having a large mass, a hunting phenomenon (small vibration of low frequency) in which the drum rotation speed becomes unstable during running is likely to occur, and the traveling performance of the vehicle (vehicle roll motion).
Could be affected.

[0008] The present invention has been made in view of the above problems, and has as its object to provide a mixer drum drive control device capable of improving the running stability of a vehicle.

[0009]

According to a first aspect of the present invention, there is provided a mixer drum rotatably mounted on a vehicle, and a variable displacement pump and a motor capable of adjusting a discharge capacity for rotating the mixer drum in forward, reverse, increasing, and decelerating rotations. A driving device,
A traveling engine drive for increasing and decelerating the drive, a transport speed command means for generating a target drum rotation speed in accordance with the rotation speed of the traveling engine drive, and the traveling engine drive And a pump displacement control means for calculating the displacement of the variable displacement pump required for the target drum rotation speed from the rotation speed and the displacement of the motor and controlling the displacement of the variable displacement pump.

According to a second aspect of the present invention, in the first aspect, the transport speed command means outputs the target drum rotational speed based on a predetermined pattern set over the entire rotational speed of the traveling engine drive device. It is characterized by doing.

[0013] In a third aspect based on the first or second aspect, the predetermined pattern is a rotation speed of the traveling engine drive unit ranging from an idling rotation speed of the traveling engine drive unit to a predetermined rotation speed region. It rises along with the rise, and suppresses an increase in the drum rotation speed against an increase in the engine rotation speed from the predetermined rotation speed region to the maximum rotation speed.

In a fourth aspect based on any one of the first to third aspects, the target drum rotation speed is increased or decreased in accordance with a set position of a slump setting means provided in a driver's seat. Features.

In a fifth aspect based on any one of the first to third aspects, the target drum rotation speed is increased or decreased in accordance with a set position of a transport time setting means provided in a driver's seat. It is characterized by.

[0014]

Therefore, in the first invention, the target drum rotational speed is set as a function of the rotational speed of the traveling engine drive device during traveling, so that the drum rotational speed is determined in consideration of the traveling load of the vehicle. The drum driving load can be set to be small, and the running stability during running can be improved.

Further, the target drum rotation speed can be suppressed to a low rotation speed in accordance with the rotation speed of the driving engine drive device. The change in speed can be set to be suppressed so that the running stability can be further improved, and the fuel consumption of the driving engine drive device can be reduced.

Further, since the pump displacement control means calculates and controls the required pump displacement from the target drum rotational speed, the motor displacement, and the rotational speed of the traveling engine drive device, it is a so-called open loop control. Although the accuracy and responsiveness of the drum rotation speed are slightly reduced, the stability can be improved, and the hunting phenomenon due to the instability of the drum rotation speed and the accompanying impairment of the running performance of the vehicle do not occur. Can be optimized for a control object having a large value.

Further, when the correction means or the like further corrects the target drum rotation speed input to the pump displacement control means based on the deviation between the rotation speed of the mixer drum and the target drum rotation speed, the control accuracy of the rotation speed of the mixer drum can be improved.

In the second invention, in addition to the effect of the first invention, the target drum rotational speed is based on a predetermined pattern set over the entire rotational speed of the traveling engine drive device. The target drum rotation speed can be finely instructed according to the rotation state of the engine driving device for use, and the effect of the first invention can be exhibited more efficiently.

According to a third aspect of the present invention, in addition to the effects of the first or second aspect, the drum rotational speed is suppressed from increasing with respect to the engine rotational speed from the predetermined rotational speed region to the maximum rotational speed. It is possible to reduce the drum rotation load during acceleration and high speed running, improve running performance,
The change in the drum rotation speed with respect to the change in the rotation speed of the traveling engine drive device is suppressed, and the influence on the traveling performance can be reduced.

A target drum rotation speed which increases with an increase in the rotation speed of the driving engine drive device from an idling rotation speed of the driving engine drive device to a predetermined rotation speed region, in other words, the drum speed increases as the engine rotation speed increases. Because it increases the rotation speed,
By making the pump displacement constant, the frequency of the pump displacement control at the time of discharging the minute flow rate is reduced, and the instability of the drum rotation speed due to frequent pump displacement control at the time of discharging the minute flow rate can be eliminated.

In the fourth invention, in addition to the effect of any one of the first to third inventions, the target drum rotation speed is adjusted according to the slump value of the ready-mixed concrete to be mounted. Drum rotation speed is obtained, and the quality of ready-mixed concrete is more maintained.

Further, the target drum rotation speed can be easily changed by changing the slump value even during traveling, and the quality of the ready-mixed concrete being transported can be easily maintained.

In the fifth invention, in addition to the effect of any of the first to third inventions, the target drum rotation speed is adjusted according to the transport time, so that the total number of rotations of the drum is independent of the transport time. It can be kept constant and the quality of ready-mixed concrete can be maintained as a whole.

[0024]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 shows a drive system configuration diagram of a mixer drum (hereinafter, simply referred to as a drum) 1. The drive system of the mixer drum 1 includes an engine 2, a variable displacement pump 3, a variable displacement motor 4, and a speed reducer 5. A controller 6 for controlling the drive system and operating devices 7 to 9 are provided.

During the running of the vehicle, the rotation speed of the engine 2 is changed in accordance with the operation of the accelerator pedal by the vehicle driver. The rotation speed is detected by a rotation speed detection sensor 12 and is output as a rotation speed signal Ne to the controller 6.
Is input to

When the vehicle is stopped, the rotation speed is adjusted based on the rotation speed command signal Ner from the controller 6 to the engine 2 based on the opening of the throttle valve 11 operated by the throttle adjustment device 10 functioning as an actuator. . That is, the rotation speed of the engine 2 is increased to a higher rotation speed than in the idle state where the accelerator is off when the vehicle is stopped.

Although not shown, when the engine 2 employs an engine control controller for exhaust gas control or the like, a rotation speed command signal Ner and a rotation speed command are transmitted between the engine control controller and the controller 6. This can be handled by transmitting and receiving the signal Ne.

The variable displacement pump 3 driven by the engine 2 receives a pump displacement command signal Dpr from the controller 6 and corrects the tilt angle of the variable displacement pump 3 in accordance with the input signal, although details are omitted. The discharge direction and the discharge capacity are adjusted by the solenoid valve 13 which switches between the reverse direction and the reverse direction and adjusts the tilt angle.

The discharge direction and discharge capacity of the variable displacement pump 3 are input to the controller 6 by the displacement detection sensor 14 as a pump displacement signal Dp.

Although the details of the variable displacement motor 4 are omitted, the solenoid valve 1 for adjusting the tilt angle of the variable displacement motor 4 in response to the motor displacement command signal Dmr from the controller 6.
The variable displacement pump 3 rotates by receiving the supply of the discharge fluid from the variable displacement pump 3. The variable displacement motor 4
Is proportional to the supply flow rate Q and inversely proportional to the capacity per rotation Dm, and Nm = Q / Dm.

The rotation speed of the variable displacement motor 4 is input to the controller 6 by the rotation speed detection sensor 16 as a motor rotation speed signal Nm.

The variable displacement motor 4 does not need a motor whose displacement can be continuously changed from a small displacement to a large displacement. For example, the variable displacement motor 4 has two stages of a small displacement for high-speed rotation and a large displacement for normal rotation. May be changed, or a constant displacement motor whose displacement does not change may be used. In the case of a constant displacement motor, the solenoid valve 15 is unnecessary.

The speed reducer 5 is driven by the variable displacement motor 4 and drives the mixer drum 1 at a rotation speed Nd obtained by reducing the rotation speed Nm at a predetermined reduction ratio.

FIG. 2 shows an example of the specific structure of the driver's seat operating device 7. A changeover switch 20 as an input means having a built-in lamp 21 as a display means, and a drum rotation setting switch as a rotation setting means. 22. Injection, stirring, neutral, and discharge lamps 2 that indicate the drum rotation status
3 and a slump value selection switch 24 and are connected to the controller 6.

The changeover switch 20 transmits an operation right changeover request signal to an operation determination section 31 of the controller 6 to be described later through an operation signal U1.
The built-in lamp 21 is lit and displayed by the display signal D1 from the operation determination unit 31 when the operation device 7 has the operation right, and is turned off when the operation right is in the other operation devices 8 and 9, and the switching is performed. When the operation right is requested by the switch 20 but the condition for switching the operation right is not satisfied, the display is blinked.

The rotation setting switch 22 is a switch that is operated to set the rotation mode of the drum 1 while the built-in lamp 21 has the operation right while the lamp 21 is turned on. Side operation,
The rotation setting signal is transmitted to the controller 6 through the operation signal U1.

The rotation setting switch 22 can change the drum rotation state from neutral to stirring, from stirring to charging, and from discharging to neutral by operating the UP side.
By the OWN operation, the drum rotation state can be changed from neutral to discharge, charging to stirring, and stirring to neutral, contrary to the UP operation.

The rotation state of the drum 1 can be confirmed by the lighting state of the input, stirring, neutral and discharge rotation state display lamps 23 selectively displayed by the display signal D1 from the operation discriminator 31 of the controller 6. .

The slump value selection switch 24 is operated by the operator in accordance with the slump value of the ready-mixed concrete to be loaded. For example, high, medium and low are selected as shown in the figure. The selected slump value is transmitted as a slump value setting signal through an operation signal U1 via an operation determination unit 31 of the controller 6 to be described later, and a transfer speed command unit 33 (transport speed command unit) of the drum rotation speed command generation unit 32. ).

Note that the built-in lamp 21 is not necessarily built in the changeover switch 20 and may be arranged separately. The lamp 21 only needs to be able to display the presence or absence of the operation right. Therefore, in addition to the lamp 21, a display means (not shown) for displaying characters or symbols, for example, a liquid crystal display may be used.

The operating devices 8 and 9 outside the vehicle are (operating device 8
And 9 have the same configuration, only the operation device 8 will be described). FIG. 3 shows an example of a specific configuration thereof. A lamp 26 as display means is provided as a changeover switch 25 as built-in input means, and as a rotation setting means. Rotation setting dial 27
And is connected to the controller 6.

The changeover switch 25 sends an operation right signal to an operation discriminator 31 of the controller 6 to be described later.
2 (the operating device 9 is U3).
The built-in lamp 26 is operated by the display signal D2 (D3 for the operation device 9) from the operation discrimination section 31 to operate the operation device 8.
Is turned on when the user has the operation right, and turned off when the operation right is in the other operation devices 7 and 9.
5, when the operation right is requested but the condition for switching the operation right is not satisfied, the display is blinked.

The rotation setting dial 27 is a dial that is operated to set the rotation speed of the drum 1 while the built-in lamp 26 has an operation right while the lamp 26 is turned on. Direction, the drum 1 is rotated at a low speed, the stirring position, the medium-speed rotation input position,
In addition, a high-speed position can be obtained although the position is not displayed, and a reverse rotation can be obtained by rotating in the counterclockwise direction, so that a discharge position facing the time of closing can be obtained, and the operation signal U2 can be obtained as a rotation setting signal. Is transmitted to the controller 6 through

The reference numerals of the respective parts of the operating device 9 are a changeover switch 25a, a built-in lamp 26a, and a rotation setting dial 27a.

Further, the lamps 26 and 26a built in the changeover switch 25 do not necessarily have to be built in, and may be arranged separately from the switches. It is sufficient that the operation status can be displayed, and is not limited to a lamp.
Display means for displaying characters or symbols (for example, liquid crystal display) may be used.

FIG. 4 shows the details of the controller 6, which comprises an operation discriminating unit 31, a drum rotation command generating unit 32 incorporating a speed command unit 33 during transport, a drum rotation control unit 34, and a drum rotation conversion circuit 35.

The operation determining section 31 has a function of monitoring a switching request signal, a rotation setting signal, and a slump value setting signal of the driver's seat and the operating devices 7 to 9 outside the vehicle by operating signals U1 to U3.

Then, an operating right is set to any of the operating devices 7 to 9 (the operating device 7 in the driver's seat may be set when the engine is started).
9 (hereinafter referred to as the operation device 7 and the operation device 8 is described in parentheses) in accordance with the rotation setting signal from the rotation setting switch 22 and the rotation setting signal from the (rotation setting dial 27). Output function.

The presence or absence of the operation right is determined by the set operating device 7.
Lamp 21 (2) built into switch 20 (25)
6) is turned on to indicate that the user has the operation right, and the lamp 2 built in the changeover switches 25, 25a (21, 26a) of the other operation devices 8, 9 for which the operation right is not set.
6, 26a (21, 26a) are turned off to indicate that there is no operation right.

Also, the operation right is set to the operation devices 8 and 9 (here, from the operation device 7 to the operation device 8) for which the operation right is not set.
The changeover switch 2 will be described.
By pressing 5, a switching request signal is output to the operation discriminating unit 31, and if a predetermined condition is satisfied, the operation right is changed to the operating device 8 that issued the switching request signal, The built-in lamp 21 of the changeover switch 20 is turned off, and the built-in lamp 26 of the changeover switch 25 of the operating device 8 to be changed is turned on to indicate that the operation right has been moved.

The predetermined condition is that when the setting position of the rotation setting dial 27 of the operating device 8 to be switched to is a position such as neutral or agitation, the operating device 8 to be switched to is changed.
Switching to is allowed.

For example, although not shown, this permission condition is provided with a permission condition storage means, which is stored in the permission condition storage means. The storage contents can be changed, and the contents of the switching destination operation devices 7 to 9 can be changed. The rotation setting position can be changed so that workability is improved.

Further, even when the changeover switch 25 of the operating device 8 is operated (pushed) to input an operation right switching request signal (for example, when switching from the operating device 7 to the operating device 8), If the permission condition is not satisfied, the built-in lamp 2 of the changeover switch 25 of the operating device 8 is used.
An alarm is issued by blinking 6.

Further, (for example, when the operation right is in the operation device 8), the rotation setting means 22, 27a of the operation devices 7, 9 without the operation right are operated to change the rotation state of the drum 1. In this case, the fact that the operation is not permitted is displayed by blinking the built-in lamps 21 and 26a of the changeover switches 20 and 25a of the operation devices 7 and 9.

In the above description, the switching of the operation right from the operating device 7 to the operating device 8 has been described. However, any of the operating devices 7 to 9 can be a change source and a change destination.

The setting of the slump setting switch 24 of the operating device 7 in the driver's seat is output as a slump value setting signal Us to the drum rotation command generation unit 32, and the drum rotation command generation unit 32 has a built-in conveyance speed command unit. 33 is input as described later.

The drum rotation command generating section 32 stores a rotation speed (a stirring rotation speed, a charging rotation speed, a discharge rotation speed) and a rotation pattern stored in response to an operation command signal U input from the operation determination portion 31. (The rotational speed changes with the passage of time) is output to the drum rotation control unit 34 as a drum rotation speed command Ndr. Have.

The stored various rotational speeds and rotational patterns are stored in accordance with the slump value or as parameters for increasing or decreasing the rotational speed and rotational pattern of the slump value. The pattern can be arbitrarily changed by a setting operation.

As shown in FIG. 5, the transfer speed command unit 33 storing the drum rotation speed pattern during transfer has a storage unit 40 storing an automatic speed control pattern corresponding to the engine rotation speed signal Ne. A slump coefficient selection circuit 42 selected by the slump value setting signal Us from the operation determination unit 31, an automatic speed rotation speed command Ndv output from the storage unit 40, and a slump coefficient K output from the slump coefficient selection circuit 42. And a drum rotation speed command Nd output from the multiplier 43.
r is output to the drum rotation controller 34.

The storage unit 40 stores, for example, a minimum drum rotation speed command Nmin and a maximum drum rotation speed command Nmax for conveying raw concrete with a standard slump value.
And the rotational speed of the engine is the rotational speed at idling Ne.
An automatic speed rotation speed command Ndv that changes in a predetermined pattern corresponding to each rotation speed that changes from 0 to the maximum rotation speed Nemax during traveling is stored.

Therefore, during traveling, the storage unit 40
Output from the minimum drum rotation speed command Nmin of the idling rotation speed Ne0 to the maximum drum rotation speed command Nmax of the running maximum rotation speed Nemax according to the input engine rotation speed signal Ne. Change according to a predetermined pattern.

Since the predetermined drum rotation speed pattern is a target drum rotation speed Ndv = Nmax which is constant from a predetermined rotation speed region to a maximum rotation speed Nemax, the drum rotation load during acceleration or high-speed running is reduced. In this way, it is possible to satisfy required traveling characteristics such as reducing traveling load.

From the idling rotational speed Ne0 of the traveling engine 2 to a predetermined rotational speed region, the target drum rotational speed Ndv (= Ndr) increases as the rotational speed Ne of the traveling engine 2 increases.
As the engine rotation speed Ne increases, the drum rotation speed N
Since dv is increased, the pump displacement Dp is kept constant, so that pump displacement control at the time of discharging at a small flow rate can be suppressed, and the drum rotational speed Nd is further stabilized.

The drum rotation speed pattern composed of the target drum rotation speed Ndv is not limited to the above, and may be, for example, for the purpose of improving the vehicle running characteristics or the purpose of improving the running fuel efficiency.
It is also possible to set so as to be adjusted by other factors.

The slump coefficient selection circuit 42 stores a plurality of slump coefficients from a low slump coefficient to a high slump coefficient with a standard slump coefficient therebetween.
H, K1, KL, and any of the coefficient storage units KH, K1,
KL is selected according to a slump value setting signal Us (high / medium / low), and a selecting means SW for outputting a slump coefficient K of the selected coefficient storage units KH, K1, and KL.

The coefficient storage unit K1 is selected when the slump setting signal Us corresponding to the standard kneading drum rotation speed pattern stored in the storage unit 40 is input, and the slump coefficient K = 1 is selected. Output and coefficient storage unit KH
Outputs a slump coefficient K that is selected when a slump setting signal Us with a high slump value is input and exceeds one,
The coefficient storage unit KL stores a low slump value slump setting signal U.
When s is input, it is selected and outputs a slump coefficient K less than 1.

Accordingly, the automatic speed rotation speed command Ndv from the storage unit 40 and the slump coefficient K from the slump coefficient selection circuit 42 are multiplied by the multiplier 43, and the drum rotation speed command corresponding to the engine speed and the slump value is obtained. Ndr
Is output.

In the above-mentioned transfer speed command unit 33, the pattern of the automatic speed rotation speed command Ndv for the standard slump value is stored in the storage unit 40, and this automatic speed rotation speed command Ndv is stored.
The dv pattern is multiplied by the coefficient K of the slump value. However, the transport speed command unit 33 is not limited to the above. A plurality of speed command Ndv patterns may be stored, and a corresponding automatic speed rotation speed command Ndv pattern may be selected according to the slump setting signal Us to output the drum rotation speed command Ndr in conjunction with the engine rotation speed. Good.

As described above, the automatic speed rotation speed command Nd
When a plurality of v patterns are stored, the minimum drum rotation speed command Nmin, the maximum drum rotation speed command Nmax, and the automatic speed rotation speed command Ndv pattern Ndv can be individually set so as to be optimal according to the slump value.

The drum rotation speed control unit 34 receives the drum rotation speed command Nd from the drum rotation speed command generation unit 32.
r, the rotation speed of the drum 1, that is, the drum rotation speed N
The control is performed so that the drum rotation speed Nd fed back from m via the drum rotation conversion circuit 35 becomes the drum rotation speed command Ndr.

Specifically, as shown in FIG. 6, a pump displacement converter 46, a PID compensator 47, and a motor displacement setting device 4
8, a reduction ratio storage unit 49, a rotational speed command assurance device 50, and an adder 51.

The drum rotation speed command Ndr is added to the rotation speed command compensation amount Und output from the rotation speed command compensator 50 by the adder 51 and input to the pump displacement converter 46.
The pump displacement converter 46 receives the motor displacement command Dmr from the motor displacement setting unit 48, the reduction ratio signal Rg from the reduction ratio storage unit 49, and the engine rotation speed signal Ne, and calculates the rotation speed command compensation amount Und. Target pump displacement command D required to obtain compensated drum rotation speed command Ndr
The value of “po” is calculated and output to the PID compensator 47.

In the above description, the motor capacity command Dmr from the motor capacity setting unit 48 is set to the maximum value during the running of the vehicle because the drum 1 is not rotated at a high speed during the running of the vehicle.

The PID compensator 47 outputs a displacement command Dpr to the variable displacement pump 3 so that the displacement signal Dp from the displacement detection sensor 14 of the variable displacement pump 3 matches the target pump displacement command Dpo. The pump displacement converter 46 and the PID compensator 47 constitute a pump displacement control means. This pump displacement control means controls only the displacement Dp of the variable displacement pump 3 necessary for the drum rotation speed command Ndr. It is in loop control.

The drum rotation speed signal Nd from the drum rotation conversion circuit 35 (FIG. 4) is compared with a drum rotation speed command Ndr by a rotation command compensator 50, and the difference is used as a rotation speed command compensation value Und as an adder 51. Output to The rotation command compensator 50 and the adder 51 constitute a correction unit,
Drum rotation speed command Nd input to pump displacement control means
Since r is corrected, control accuracy of the rotational speed of the mixer drum 1 can be improved.

During running, the engine speed Ner is:
No output.

Next, the operation will be described. 1 to 6, when the vehicle is stopped, immediately after the start of the engine 2 of the mixer vehicle, a rotation setting switch (rotation setting dial 27, 27) is operated by a rotation stop operation of the drum 1 at the end of the previous operation.
a) 22 is set to a neutral state, and the capacity D of the variable displacement pump 3
p is neutral zero, and the drum 1 is in a neutral state in which the rotation of the drum 1 is stopped.

When the operator operates the operating device 7 in the driver's seat or one of the operating devices 8 and 9 outside the vehicle (here, the operating device 7 in the driver's seat), the built-in lamp lamp 21 of the changeover switch 20 displays the display of the controller 6. When the operation right is turned on by the signal D1 (the built-in lamps 26 and 26a of the operation devices 8 and 9 are turned off), the rotation setting switch 2 is turned on.
For example, if the user operates the UP side to set the stirring position or the like, an operation signal (rotation setting signal) U1 is input to the operation determination unit 31 of the controller 6, and the operation determination unit 31 performs an operation from the operation device 7 having the operation right. The operation signal U1
Is output to the drum rotation command generation unit 32.

The drum rotation command generator 32 extracts a drum rotation speed command Ndr corresponding to the operation command U from the stored drum rotation speed commands Ndr and outputs the same to the drum rotation controller 34.

As described above, the drum rotation speed control circuit 34 controls the engine rotation speed Ner (only when the vehicle is stopped), the pump displacement command Dpr, and the motor displacement so that the drum rotation speed Nd matches the drum rotation speed command Ndr. Command Dmr, and calculates the throttle adjustment device 10
(Only when the vehicle is stopped), outputs to the variable displacement pump 3 and the variable displacement motor 4.

Then, the throttle adjusting device 10 controls the engine speed Ne according to the engine speed command Ner.
(Only when the vehicle is stopped), the variable displacement pump 3 adjusts the flow rate Q to be discharged according to the engine rotation speed Ne and the pump displacement command Dpr, and the variable displacement motor 4
And the motor rotation speed N according to the motor displacement command signal Dmr.
m is adjusted.

Furthermore, the motor rotation speed Nm is
Is further converted into the drum rotation speed Nd, and finally the drum rotation speed Nd is adjusted, whereby the drum rotation speed Nd is adjusted.
d automatically changes in response to the rotation setting signal (stirring position) of the rotation setting switch 22 of the operating device 7, and the drum rotation is performed by the display signal D 1 from the operation determining unit 31 of the controller 6 to the operating device 7 in the driver's seat. The lamp at the stirring position of the state display lamp 23 is turned on to indicate that the stirring state is established.

Next, a case where a ready-mixed concrete is mounted and transported will be described.

First, after putting in the plant factory,
The operator operates the slump setting switch 24 of the operation device 7 in the driver's seat to select a slump value corresponding to the ready-mixed concrete.

The selected slump values (high / medium / low)
The slump setting signal is input to the operation determining unit 31 through the operation signal U, and the slump setting signal Us is input to the transport speed command unit 33 of the drum rotation command generating unit 32.

As the slump coefficient selecting means 42 of the speed command section 33 during the transfer, a slump coefficient storing means (KH, K1, Kl) corresponding to the slump setting signal Us is selected. At the same time, the operator operates the rotation setting switch 22 (or the rotation setting dials 27, 27a) to change the rotation state of the drum 1 by using any of the operation devices 7 to 9, and stirs the ready-mixed concrete by setting the rotation state of the drum 1 to stirring.

When the vehicle is started in this state, the engine rotation speed Ne is input to the storage unit 40 of the transfer speed command unit 33, and the automatic speed rotation speed command Ndv output in accordance with the engine rotation speed Ne is calculated as described above. The slump coefficient K from the slump coefficient selection circuit 42 is multiplied by the multiplier 43 and input to the pump displacement converter 46 via the adder 51 of the drum rotation control unit 35 as the drum rotation speed command Ndr.

The pump displacement converter 46 receives the motor displacement command Dmr set to the maximum value from the motor displacement setting unit 48, the reduction ratio signal Rg from the reduction ratio storage unit 49, and the drum rotation speed command from the engine rotation speed signal Ne. The target pump displacement command Dpo required to obtain Ndr is calculated and output to the PID compensator 47.

The PID compensator 47 outputs a displacement command Dpr to the variable displacement pump 3 so that the displacement signal Dp from the displacement detection sensor 14 of the variable displacement pump 3 matches the input target pump displacement command Dpo.

The control from the pump displacement converter 46 to the PID compensator 47 and the variable displacement pump 3 based on the drum rotation speed command Ndr is an open loop.

The drum rotation speed Nd and the drum rotation speed command Ndr are compared by the rotation command compensator 50, and the difference is output to the adder 51 as the rotation speed command compensation value Und, and is superimposed on the drum rotation speed command Ndr. Then, it is input to the pump capacity converter 46.

The rotational speed command compensation value Und in this case is
Drum rotation speed Nd with respect to drum rotation speed command Ndr
And corresponds to the machine difference of the drum driving device to which the error of the engine rotation speed Ne of the engine 2, the capacity error of the variable displacement pump 3, the capacity error of the motor 4, etc. are added, but the rotation speed Nd of the drum 1 Is finally corrected by the rotation speed command compensation value Und to improve the control accuracy of the drum rotation speed Nd with respect to the drum rotation speed command Ndr.

If the user notices that he has forgotten to set the slump setting switch 24 to the set value of the ready-mixed concrete after the start of the running of the vehicle, the slump setting switch 2
By resetting 4, the slump setting signal Us is input to the transport speed command unit 33 of the drum rotation command generation unit 32 via the operation determination unit 31 of the controller 6 as described above,
The slump coefficient selection circuit 42 operates to change the slump coefficient signal K, and the drum rotational speed command Ndr is immediately changed via the multiplier 43. Therefore, quality deterioration of ready-mixed concrete due to inappropriate drum rotation speed can be prevented.

The present embodiment has the following effects.

Since the target drum rotation speed Ndr is set as a function of the rotation speed Ne of the traveling engine 2 during traveling, the drum 1 rotation speed Nd is reduced in consideration of the traveling load of the vehicle. It can be set to be small, and running stability during running can be improved.

Further, the target drum rotation speed Ndr can be suppressed to a low rotation speed in accordance with the rotation speed Ne of the traveling engine 2, and the drum rotation speed Ndr changes with the change in the rotation speed Ne of the engine 2. The change in the speed Nd can be set to be suppressed, so that the running stability can be further improved and the fuel consumption of the engine 2 can be reduced.

Further, the pump capacity capacity converter 46 and the PI
Since the pump displacement control means composed of the D compensator 47 calculates and controls the required pump displacement Dp from the target drum rotational speed Ndr, the motor displacement Dm, and the rotational speed Ne of the engine 2, it is so-called open. This is a loop control, and although the accuracy and responsiveness of the drum rotation speed Nd are slightly reduced, the stability can be improved. In other words, it is possible to optimize the control target having a large load such as the mixer drum 1.

When the target drum rotation speed Ndr inputted to the pump displacement control means is corrected based on the deviation between the rotation speed Nd of the mixer drum 1 and the target drum rotation speed Ndr by the correction means including the rotation speed command compensator 50, etc.
The control accuracy of the rotation speed Nd of the mixer drum 1 can also be improved.

Further, since the target drum rotational speed Ndr is based on a predetermined pattern set over the entire rotational speed Ne of the traveling engine 2 during traveling, the engine 2
Target drum rotation speed Nd
r can be commanded.

From the predetermined rotation speed region of the engine 2 to the maximum rotation speed, the increase in the drum rotation speed is suppressed with respect to the increase in the engine rotation speed. The driving performance can be reduced, and the change in the drum rotation speed with respect to the rotation speed change of the driving engine drive device can be suppressed, so that the influence on the driving performance can be reduced.

Further, the target drum rotation speed Ndr increases as the rotation speed of the engine 2 increases from the idling rotation speed Ne0 of the traveling engine 2 to a predetermined rotation speed region, in other words, the drum speed increases as the engine rotation speed Ne increases. Since the rotation speed Nd is increased, the frequency of the pump displacement control at the time of discharging the minute flow rate is reduced by keeping the pump displacement Dp constant, and the rotation speed Nd of the drum due to the frequent pump displacement control at the time of discharging the minute flow rate is reduced. Instability can be eliminated.

Further, since the target drum rotation speed Ndr can be adjusted according to the slump value of the ready-mixed concrete, the drum rotation speed Nd according to the properties of the ready-mixed concrete can be obtained, and the quality of the ready-mixed concrete can be further maintained.

The target drum rotation speed Ndr can be easily changed by changing the slump value even during traveling, and the quality of the ready-mixed concrete being transported can be easily maintained.

FIGS. 7 and 8 show a second embodiment of the present invention. In contrast to the embodiments shown in FIGS. 1 to 6, the operation device 7 for the driver's seat and the drum rotation command generator 32 of the controller 6 are provided. Is changed so that the total number of rotations of the drum during the period of transporting the ready-mixed concrete from the input at the ready-mixed concrete plant to the discharge at the construction site is substantially the same regardless of the transport time. is there. The same parts as those in FIGS.

The operating device 7 for the driver's seat shown in FIG. 7 is connected to the controller 6 and has a changeover switch 20 as input means including a lamp 21 as display means similar to the operating device 7 shown in FIG. As shown in FIG. 2, a drum rotation setting switch 22 as a means, and input, stirring, neutral, and discharge lamps 23 for displaying a drum rotation state are provided.
Is different from the operating device 7 shown in FIG.

The transfer time selection switch 28 is used by an operator to select the transfer distance and transfer time between a ready-mixed concrete plant into which ready-mixed concrete is to be supplied and a construction site to discharge the ready-mixed concrete.・ We choose short. The selected transport time is transmitted as a transport time signal Usa to the transport speed command unit 33 of the drum rotational speed command generator 32 via an operation determination unit 31 of the controller 6 through the operation signal U1 as a transport time setting signal. Is entered.

8 is configured as a time coefficient selection circuit 61 instead of the slump coefficient selection circuit 42 of the conveyance speed instruction unit 33 in FIG. 5, and includes another storage unit 40 and a multiplier 43. There is no change in the configuration.

The time coefficient selection circuit 61 stores a plurality of coefficients from a coefficient for a relatively short conveyance to a coefficient for a relatively long conveyance with a coefficient for a standard conveyance time interposed therebetween. ), K (1), K (S)
And one of the coefficient storage units K (L), K (1), K
(S) is selected according to the transport time setting signal Usa (long / medium / short), and the selected coefficient storage units K (L), K (1), and K are selected.
And selecting means SW for outputting the transfer time coefficient K of (S).

The coefficient storage unit K1 is selected when the transfer time setting signal Usa matching the standard transfer time drum rotation speed pattern stored in the storage unit 40 is input, and the transfer time coefficient K1 is selected. = 1 and the coefficient storage unit K (L) is selected when the relatively long transfer time setting signal Usa is input, outputs a transfer time coefficient K less than 1, and outputs the coefficient storage unit K (L). S) is selected when a relatively short transfer time setting signal Usa is input, and outputs a transfer time coefficient K exceeding one.

Therefore, the automatic speed rotation speed command Ndv from the storage unit 40 and the transfer time coefficient K from the slump coefficient selection circuit 61 are multiplied by the multiplier 43, and the drum rotation speed corresponding to the engine speed and the transfer time is multiplied. Command Ndr is output.

With this configuration, the drum rotation speed command Ndr can be set to a low rotation speed for a relatively long transport,
In addition, a high rotation speed is set for a relatively short transport. Therefore, regardless of the length of the transfer time, the total number of rotations of the drum in the ready-mixed concrete transfer period from the input at the ready-mixed concrete plant to the discharge at the construction site can be made substantially the same regardless of the transfer time.

In this embodiment, in addition to the effects of the embodiments of FIGS. 1 to 6, the target drum rotation speed Ndr is adjusted according to the transport time, so that the total number of rotations of the drum is independent of the transport time. It can be kept constant and the quality of ready-mixed concrete can be maintained as a whole.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a drive system for a mixer drum according to an embodiment of the present invention.

FIG. 2 is a layout diagram showing a specific example of a driver's seat operating device.

FIG. 3 is a layout diagram showing a specific example of an operation device outside the vehicle.

FIG. 4 is a block diagram of a controller.

FIG. 5 is a block diagram illustrating a transfer speed command unit.

FIG. 6 is a block diagram showing a drum rotation control unit of the controller.

FIG. 7 is a layout diagram of a driver's seat operating device according to a second embodiment of the present invention.

FIG. 8 is a block diagram illustrating a transport speed command unit according to a second embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Drum 2 Engine 3 Variable displacement pump 4 Variable displacement motor 5 Reducer 6 Controller 7, 8, 9 Operating device 10 Throttle adjusting device 11 Throttle 12, 16 Rotation speed detection sensor 13, 15, Solenoid valve 14 Capacity detection sensor 20, 25, 25a selector switch 21, 26, 26a lamp (display means) 22 rotation setting switch 23 drum rotation status display lamp 24 slump setting switch (slump setting means) 27, 27a rotation setting dial 28 transport time selection switch (transport time selection means) 31 Operation discriminator (operation discriminator) 32 Drum rotation command generator 33, 60 Transport speed commander (transport speed commander) 34 Drum rotation controller 40 Storage unit 42 Slump coefficient selection circuit 43 Multiplier 46 Pump capacity converter (Pump capacity control means) 4 PID compensator (pump capacity control means) 50 rotational speed command compensator (rotational speed correction means) 61 hours coefficient selection circuit

Claims (5)

[Claims] 1. A drive unit comprising a mixer drum rotatably mounted on a vehicle, a variable displacement pump and a motor capable of adjusting a discharge capacity for rotating the mixer drum forward, reverse, and increasing, and decelerating, and a drive device comprising: A traveling engine drive for rotating at a reduced speed; a transport speed command means for generating a target drum rotational speed in accordance with a rotational speed of the travel engine drive; a rotational speed and a motor of the travel engine drive And a pump displacement control means for calculating the displacement of the variable displacement pump required for the target drum rotational speed from the displacement and controlling the displacement of the variable displacement pump. 2. The method according to claim 1, wherein the conveying speed command means outputs a target drum rotation speed based on a predetermined pattern set over the entire rotation speed of the driving engine drive device. A mixer drum drive control device as described in the above. 3. The predetermined pattern increases as the rotation speed of the driving engine drive increases from an idling rotation speed of the driving engine drive to a predetermined rotation speed region, and increases from the predetermined rotation speed region to a maximum. 3. The mixer drum drive control device according to claim 2, wherein an increase in the drum rotation speed is suppressed with respect to an increase in the engine rotation speed up to the rotation speed. 4. The apparatus according to claim 1, wherein the target drum rotation speed is increased or decreased in accordance with a set position of a slump setting means provided in a driver's seat. Mixer drum drive controller. 5. The apparatus according to claim 1, wherein the target drum rotation speed is increased or decreased according to a set position of a transfer time setting unit provided in a driver's seat. Mixer drum drive control device.