JP2003213667A - Control device for ground improving machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To always keep the blade cutting frequency per unit length or the discharge quantity of an improving agent or the both at a set value or more. <P>SOLUTION: The actual values ΔNs and Δqs of the blade cutting frequency per unit length and the improving agent discharge quantity are compared with set values ΔN and Δq every time when the vertically moving quantity of a stirring blade reaches a unit length, and the vertically moving action to the next unit length is continued under the condition that ΔNs is equal to or larger than ΔN, and Δqs is equal to or larger than Δq. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ground improvement machine for injecting a ground improvement material into a soft ground through a stirring shaft and stirring and mixing the ground improvement material with earth and sand by a stirring blade to improve the ground. The present invention relates to a control device that controls one or both of the number of blade cutting and the ground improvement material discharge amount.

[0002]

2. Description of the Related Art In this type of ground improvement method, the ground improvement material and earth and sand are mixed and the ground is improved by a chemical reaction. The quality of the improved ground depends on the quality of stirring and mixing.

Here, the number of blade cuttings and the discharge amount of the ground improvement material are factors that determine the quality of stirring and mixing.

Of these, the number of blade cutting N indicates the degree of stirring by the stirring blade, and from the ascending / descending speed V of the stirring blade and the rotation speed n, and the total number M of stirring blades, N = M × n / V The stirring / mixing effect can be enhanced by maintaining the blade cutting frequency N at a certain level or more with respect to the unit vertical movement amount (unit length) of the stirring shaft.

Further, discharging a certain amount or more of the ground improvement material per unit length is a condition for maintaining a certain quality of the improved ground.

Conventionally, as a device for controlling the number of times of blade cutting and the discharge amount of the ground improvement material, Japanese Patent Laid-Open No. 2000-282544 has been proposed.
Those described in No. 1 are known.

In this known technique, the amount of vertical movement of the stirring shaft (stirring blade), the vertical speed, the number of revolutions, and the discharge amount of the improved material are detected, and the blade cutting times and the discharge amount for the sampling time are calculated from these detected values. Then, based on this, the configuration is such that the ascending / descending speed of the stirring shaft is controlled in the direction in which both the number of blade cuttings per unit length and the discharge amount are set values (slow when the tendency is insufficient and fast when the tendency is excessive). I am taking it.

By performing this control, particularly in a ground improvement machine using as a drive source a hydraulic motor whose speed changes according to load fluctuations, the number of blade cuttings and the amount of improved material discharge can be made irrespective of changes in the stirring shaft rotation speed. It can be kept close to the set value.

[0009]

However, according to this known technique, there is a certain length (sampling time) as described above.
Since the control system takes data by minute and controls the ascending / descending speed by the next length based on this data, the number of blade cutting per unit length and the amount of improved material discharge are not necessarily set values. I won't.

Although the error can be reduced by shortening the sampling time, there is no guarantee that the actual (calculated) value and the set value will match.

For this reason, the actual values of the number of blade cuttings per unit length and the improved material discharge amount may be smaller than the set values, and the intended purpose of maintaining the quality of the improved ground cannot be sufficiently achieved.

[0012] Therefore, the present invention provides a control device for a ground improvement machine, which can keep the number of blade cuttings per unit length, the amount of improvement material discharged, or both of them at least above a set value.

[0013]

According to a first aspect of the present invention, a reader standing on the surface of the earth is provided with a stirring shaft which is rotated and moved up and down by a rotation driving mechanism and a lifting driving mechanism, and the stirring shaft penetrates into the ground. In this state, while discharging the ground improvement material into the ground by the improvement material discharge means, the ground improvement material is stirred and mixed with the earth and sand by the rotation of the stirring blade provided at the lower end of the stirring shaft to improve the ground. In the ground improvement machine, the ascending / descending movement amount detecting means for detecting the ascending / descending movement amount of the stirring blade, the rotation speed detecting means for detecting the rotation speed of the stirring blade, and the ascending / descending operation of the stirring blade by the ascending / descending drive mechanism are controlled. A control means is provided, and this control means determines the number of blade cuttings per unit length Δ from the amount of vertical movement of the stirring blade and the number of rotations.
Ns is calculated, and each time the vertical movement amount reaches the unit length,
The configuration is such that the calculated value ΔNs of the number of blade cuttings per unit length is compared with the set value ΔN, and the raising / lowering action to the next unit length is continued on condition that ΔNs ≧ ΔN.

According to a second aspect of the present invention, a reader standing on the surface of the earth is provided with a stirring shaft that rotates and moves up and down by a rotation driving mechanism and a lifting driving mechanism, and the stirring shaft penetrates into the ground to improve the improving material. In the ground improvement machine for discharging the ground improvement material into the ground by the discharging means, the ground improvement material is stirred and mixed with the earth and sand by the rotation of the stirring blade provided at the lower end of the stirring shaft to improve the ground. An elevating / lowering movement amount detecting means for detecting an elevating / lowering movement amount of the stirring blade, a discharge amount detecting means for detecting an ejecting amount of the ground improving material, an elevating / lowering action of the stirring blade by the elevating / lowering drive mechanism and discharging of the ground improving material. And a control means for controlling the action, the control means
The discharge amount Δqs per unit length is calculated from the vertical movement amount and discharge amount of the stirring blade, and the calculated amount Δ of the ground improvement material per unit length is calculated each time the vertical movement amount reaches the unit length.
It is configured such that qs is compared with the set value Δq, and the raising / lowering action to the next unit length is continued on condition that Δqs ≧ Δq.

According to a third aspect of the present invention, a reader standing on the surface of the earth is provided with a stirring shaft which is rotated and moved up and down by a rotation driving mechanism and a lifting driving mechanism, and the stirring shaft is penetrated into the ground to improve the improving material. In the ground improvement machine for discharging the ground improvement material into the ground by the discharging means, the ground improvement material is stirred and mixed with the earth and sand by the rotation of the stirring blade provided at the lower end of the stirring shaft to improve the ground. An ascending / descending movement amount detecting means for detecting an ascending / descending movement amount of the stirring blade, a rotation speed detecting means for detecting a rotating speed of the stirring blade, a discharge amount detecting means for detecting a discharge amount of the ground improvement material, A control means for controlling the raising / lowering action of the stirring blade by the drive mechanism and the discharging action of the ground improvement material is provided, and this control means calculates the number of blade cutting times ΔNs per unit length from the ascending / descending movement amount and rotation speed of the stirring blade. In addition, the discharge amount Δqs of the soil improvement material per unit length is calculated from the vertical movement amount of the stirring blade and the discharge amount of the soil improvement material, and the vertical movement amount per unit length is calculated as the vertical movement amount reaches the unit length. Calculated value of blade cutting times ΔN
s and the set value ΔN, and the calculated value Δqs of the discharge amount of the ground improvement material per unit length is compared with the set value Δq,
It is configured to continue the elevating operation to the next unit length on condition that ΔNs ≧ ΔN and Δqs ≧ Δq.

According to the above construction, the calculated value and the set value for the number of blade cuttings per unit length (Claim 1), the ground improvement material (Claim 2), or both (Claim 3) are compared, In order to continue the raising / lowering action to the next unit length on condition that the calculated value is equal to or more than the set value,
In other words, if the calculated value does not reach the set value, the stirring blade is not moved up and down, so that the relationship of calculated value ≧ set value can be reliably maintained.

As a result, the quality of the improved ground can be kept constant, and particularly, according to the structure of claim 3, both the number of blade cuttings and the amount of the improved material discharge can be maintained at the set values or more. The ground can be maintained in high quality.

According to the second and third aspects of the present invention, there is no fear that the discharge amount of the improved material will greatly exceed the set value, and the waste of the improved material can be minimized.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described with reference to the drawings.

FIG. 1 shows a schematic structure of the entire ground improvement machine to which the present invention is applied.

In FIG. 1, reference numeral 1 is a crawler type base machine, and a reader 2 is erected on the front part of the base machine 1 and supported by a reader support 3 and a stay 4.

In this leader 2, a tubular stirring shaft 6 having a plurality of stirring blades 5 at its lower end is rotatably driven by a rotation drive mechanism 7 and can be moved up and down along the leader by an elevation drive mechanism 8. It is provided in.

The elevating / lowering drive mechanism 8 is an elevating / lowering body 10 with a stirring shaft chuck 9 provided on the reader 2 so as to be vertically movable.
Is raised and lowered by a rope of a winch (not shown) mounted on the base machine 1. 11 in FIG.
Is a lifting hydraulic motor as a drive source of the lifting drive mechanism 8, and 12 is a rotating hydraulic motor as a drive source of the rotary drive mechanism 7.

FIG. 1 shows a state in which the stirring shaft 6 is set on the improved ground, and from this state, the stirring blade 5 is lowered while rotating integrally with the stirring shaft 6, and penetrates into the ground. In the step or the subsequent drawing step, the ground improvement material is discharged from a not-shown batcher plant into the ground from the lower end of the stirring shaft through the improvement material supply pipe 13 and the stirring shaft 7 which constitute the improvement material discharging means, and the stirring shaft ( By rotating the stirring blade 6), the improving material and the earth and sand of the ground are stirred and mixed to improve the ground.

In FIG. 1, reference numeral 13 is an improvement material pump which is a part of the improvement material discharge means.

Next, the structure and operation of this control device will be outlined with reference to FIG.

As the detecting means, a vertical movement amount detector 14 for detecting the vertical movement amount of the stirring shaft 6 (stirring blade 5) based on the number of rotations of the vertical movement hydraulic motor 11, and the rotation hydraulic motor 1.
A rotation speed detector 15 for detecting the rotation speed of the stirring shaft 6 (stirring blade 5) by the rotation speed of 2 and a flow meter 16 for detecting the discharge amount of the ground improvement material from the improvement material pump 13 are provided.
Detection signals from these are sent to the controller 17 as the control means.

As a specific method for detecting the number of rotations of the lifting hydraulic motor 11, for example, ropes are passed through sheaves attached to the upper and lower sides of the leader 2 and both ends of the sheave are lifted by the lifting drive mechanism 8. Stop at 10 and lift 1
A method of detecting the number of rotations of one of both sheaves rotated by raising and lowering 0 can be adopted.

When a pinion is attached to the rotary shaft of the lifting hydraulic motor 11 and the pinion is meshed with a rack gear provided on the reader 2 to lift and lower the lifting body 10, the number of rotations of the pinion is increased. May be detected by an encoder. Alternatively, the lifting hydraulic motor 1
The number of rotations of one rotation shaft may be directly or indirectly detected.

The controller 17 includes the excavation depth calculation unit 1
8, lift speed calculation unit 19, rotation speed calculation unit 20, blade cutting number calculation unit 21, blade cutting number comparison unit 22, unit blade cutting number comparison unit 23, unit length comparison unit 24, discharge amount calculation unit 25, discharge An amount comparison unit 26, a unit discharge amount comparison unit 27, and a control command unit 28 are provided.

The excavation depth calculation unit 18 calculates the excavation depth from the vertical movement amount of the stirring shaft 6, and the vertical speed calculation unit 19 calculates the vertical movement speed V of the stirring shaft 6.

The rotation speed calculation unit 20 calculates the stirring shaft rotation speed n, and the blade cutting frequency calculation unit 21 calculates the calculated rotation speed n, the ascending / descending speed V, and the preset total number of stirring blades 5. From M, the number of blade cutting times Ns for the sampling time
Is calculated by the formula of Ns = M × n / V.

The blade cutting number comparing unit 22 calculates the blade cutting number for the calculated sampling time (hereinafter, referred to as actual blade cutting number) Ns and the preset (memorized) blade cutting number (hereinafter, set blade cutting number). (Referred to as the number of times) N and sends the comparison result to the control command section 28 and the unit blade cutting number comparison section 23.

The unit blade cutting number comparison unit 23 compares the actual value ΔNs and the set value ΔN regarding the blade cutting number for each preset unit length ΔH, and sends the comparison result to the control command unit 28.

The discharge amount calculator 25 is a lift speed calculator 19
Based on the ascending / descending velocity V input from the above, and the improved material discharge amount Q obtained by the flow meter 16, the improved material discharge amount qs for the sampling time is calculated by the equation qs = Q / V.

The calculated improvement material discharge amount qs for the calculated sampling time and the preset (stored) improvement material discharge amount q are compared by the discharge amount comparison unit 26, and the comparison result is the control command unit. 28 and the unit discharge amount calculation unit 27.

Further, the unit discharge amount comparison unit 27 compares the actual value qs of the improved material discharge amount for each unit length with the set value q, and sends the comparison result to the control command unit 28.

The control command unit 28 controls the blade cutting times N, N.
A control command signal based on the comparison result of s, ΔNs and the improved material discharge amounts q, qs, Δqs is output, and the rotation speed of the lifting hydraulic motor 11 (the lifting movement speed of the stirring shaft 6) and the control command signal are output. The number of revolutions of the improvement material pump 13 (the discharge amount of the ground improvement material) is controlled.

The details of this operation will be described with reference to the flowchart of FIG.

When the control is started, the total number of stirring blades M, the number of blade cutting times N, the amount of improvement material discharge q, and the unit length ΔH are set as initial settings (step S1).

Next, the ascending / descending movement amount is detected by the ascending / descending movement amount detector 14 (step S2), and the ascending / descending velocity V is obtained from the detected ascending / descending movement amount and time in step S3, and the excavation depth is obtained in step S4. It is calculated.

Further, the rotation speed detector 15 detects the rotation speed n of the stirring blade (step S5), and the blade cutting frequency Ns for the sampling time is calculated from this rotation speed n in step S6. It is determined whether or not the length reaches ΔHs (ΔHs <ΔH).

If YES (not reached) here,
In step S8, the actual value Ns of blade cutting times and the set value N are compared.

As a result of the comparison, when N = Ns (step S9), the process proceeds to step S10, and when N> Ns (step S11), the control command unit 28 is operated at step S12.
A signal for lowering the ascending / descending speed is output from N, and conversely, when N <Ns (step S13), a signal for increasing the ascending / descending speed is output from the control command unit 28 in step S14.

Subsequently, in step S10, the improvement material discharge amount Q
Is detected, the improvement material discharge amount qs for the sampling time is calculated in step S15, and the actual value qs and the set value q of the improvement material discharge amount are compared in step S16, respectively, and q = qs (step S17) Is step S2
Return to.

Then, if q> qs (step S18), the control command unit 28 outputs a signal for increasing the improvement material discharge amount (step S19). If q <qs (step S20), the improvement material discharge amount is output. A signal for reducing the amount is output (step S21), and then the process returns to step S2.

Thus, while the unit length ΔH is not reached,
The ascending / descending speed V of the stirring shaft 6 and the amount of improvement material discharge Q are adjusted in such a manner that the number of blade cuttings and the amount of improvement material discharge each become set values N and q for the sampling time.

On the other hand, if NO in step S7, that is, if it is determined that the unit length ΔH has been reached, step S2
Moving to 2, first, the actual value ΔNs regarding the number of blade cutting per unit length (the number of unit blade cutting) is compared with the set value ΔN.

When the result of this comparison is NO (the actual value ΔNs is less than or equal to the set value ΔN), the control command unit 28 outputs a signal to stop the ascending / descending in step S23.

Next, in step S24, the actual value Δqs of the improved material discharge amount per unit length is compared with the set value Δq. If NO (Δqs ≦ Δq = insufficient modified material), the process returns to step S22 and YES. If (Δqs ≧ Δq = improved material is satisfied), the control command unit 28 is operated in step S25.
Outputs an improvement material discharge stop signal.

Then, if YES in step S22, that is, if it is determined that the actual value ΔNs of the unit blade cutting number is equal to or greater than the set value ΔN, the actual value Δqs and the set value Δq of the unit discharge amount are determined in step S26. Compared, N
In the case of O (Δqs ≦ Δq), the control command unit 28 outputs a signal for stopping the ascending / descending, and in the case of YES, it is determined that the control per unit length is completed, and the process returns to step S2.

As described above, each time the unit length is reached, the actual values (calculated values) ΔNs and Δqs of the number of blade cuttings per unit length and the improved material discharge amount are actually set values Δ.
In order to continue the raising / lowering action to the next unit length on condition that N, Δq or more, in other words, the calculated value ΔN
If s and Δqs do not reach the set values ΔN and Δq, the stirring shaft 6
In order to prevent the vertical movement, the data is taken for a certain length as in the known technique, and the ascending / descending speed and the discharge amount are controlled for the next length based on this data (steps S1 to S21 in FIG. 3) Unlike the above case, the unit blade cutting frequency Δ
The Ns and the unit discharge amount Δqs can always be set values ΔN and Δq or more.

Therefore, the quality of the improved ground can be kept constant, and in particular, in this embodiment, both the number of blade cuttings and the amount of the improved material discharge can be maintained at or above the set values, so that the improved ground can be kept at a high level. Can be kept in quality.

Further, since the discharge is stopped immediately when the actual value Δqs of the discharge amount of the improved material per unit length becomes larger than the set value Δq, the waste of the improved material can be minimized.

By the way, in the above embodiment, both the blade cutting number and the improved material discharge amount are controlled so that the calculated values are equal to or more than the set values, but it is also possible to control only one of them. Good.

Further, in the above embodiment, the case where the hydraulic motors 11 and 12 are used for the elevation drive source and the rotation drive source has been illustrated as the most effective form of this control, but the present invention uses the electric motor as the drive source. Can also be applied to.

Further, in the above embodiment, the case where the stirring blade 5 is integrally provided with the stirring shaft 6 and rotates integrally is described. It can also be applied to the case of rotating at a speed different from 6. In this case, the rotation speed of the stirring blade 5 may be calculated by adding the reduction ratio to the rotation speed of the stirring shaft 6, or the rotation speed of the stirring blade 5 may be directly detected.

Further, in the present invention, the stirring blade 5 does not move up and down integrally with the stirring shaft 6 (moves up and down independently).
It can also be applied when the configuration is adopted.

On the other hand, at a construction site or the like where height is limited, a leader provided with a rotation drive mechanism for the stirring shaft and a lifting drive mechanism is erected on the ground surface of the improved ground without using the base machine 1. In some cases, the present invention can be applied to such a ground improvement machine.

[0060]

As described above, according to the present invention, the calculated value for the number of blade cuttings per unit length (Claim 1) or the ground improvement material (Claim 2), or both of them (Claim 3). The set value is compared, and if the calculated value is greater than or equal to the set value, the lifting / lowering action to the next unit length is continued.In other words, if the calculated value does not reach the set value, the lifting / lowering operation is not performed. The relationship of ≧ set value can be surely maintained.

As a result, the quality of the improved ground can be kept constant, and in particular, according to the invention of claim 3, both the number of blade cuttings and the improved material can be maintained at or above the set values. Can keep high quality.

According to the second and third aspects of the present invention, waste of the improved material can be suppressed, which is economical.

[Brief description of drawings]

FIG. 1 is a side view showing a schematic configuration of an entire ground improvement machine including a control device according to an embodiment of the present invention.

FIG. 2 is a block configuration diagram of a control device according to the same embodiment.

FIG. 3 is a flowchart for explaining the operation of the device.

[Explanation of symbols]

1 base machine 2 leader 5 stirring blades 6 stirring shaft 7 Rotation drive mechanism 8 Lifting drive mechanism 17 Control means 14 Vertical movement amount detector (elevation movement amount detection means) 15 Rotation speed detector (rotation speed detection means) 19 Lifting speed calculator 20 Rotation speed calculation unit 21 Blade cutting frequency calculator 22 Blade cutting frequency comparison unit 23 Unit blade cutting frequency comparison unit 24 Unit length comparison section 25 Discharge rate calculator 26 Discharge amount comparison unit 27 Unit discharge rate comparison unit 28 Control command section

Claims (3)

[Claims] 1. A ground improvement material is provided by a improvement material discharge means with a stirring shaft that is rotated and moved up and down by a rotation drive mechanism and an elevation drive mechanism in a reader standing on the surface of the earth, and the stirring shaft penetrates into the ground. In the ground improvement machine that mixes and mixes this ground improvement material with earth and sand by rotating the stirring blade provided at the lower end of the stirring shaft while discharging the Elevating movement amount detecting means for detecting the amount of movement, rotation speed detecting means for detecting the rotation speed of the stirring blade, and control means for controlling the raising and lowering action of the stirring blade by the lifting drive mechanism, the control means, The number of blade cuttings per unit length ΔNs is calculated from the amount of vertical movement of the stirring blade and the number of rotations, and each time the amount of vertical movement reaches the unit length, the calculated value ΔNs of blade cutting per unit length and the set value ΔN The control device for the ground improvement machine is characterized in that it is configured to continue the ascending / descending action to the next unit length on condition that ΔNs ≧ ΔN. 2. An agitator shaft that is rotated and moved up and down by a rotation drive mechanism and an elevation drive mechanism is provided on a reader standing on the surface of the earth, and the agitating shaft is penetrated into the ground to improve the ground by an improving material discharging means. While discharging the material into the ground,
This ground improvement material is a ground improvement machine that agitates and mixes with earth and sand by rotation of a stirring blade provided at the lower end of the stirring shaft to improve the ground, and a vertical movement amount for detecting the vertical movement amount of the stirring blade. A detection unit, a discharge amount detection unit that detects the discharge amount of the ground improvement material, and a control unit that controls the lifting operation of the stirring blade and the discharge operation of the ground improvement material by the lifting drive mechanism. , The discharge amount Δqs per unit length is calculated from the vertical movement amount and discharge amount of the stirring blade, and the calculated amount Δqs of the ground improvement material discharge amount per unit length each time the vertical movement amount reaches the unit length. And set value Δq
And a control device for the ground improvement machine, which is configured to continue the elevating operation to the next unit length on condition that Δqs ≧ Δq. 3. A stirrer shaft that rotates and ascends and descends by a rotation drive mechanism and a lift drive mechanism is provided on a reader standing on the surface of the earth, and with the stirrer shaft penetrating into the ground, the improvement material discharging means improves the ground. While discharging the material into the ground,
This ground improvement material is a ground improvement machine that agitates and mixes with earth and sand by rotation of a stirring blade provided at the lower end of the stirring shaft to improve the ground, and a vertical movement amount for detecting the vertical movement amount of the stirring blade. Detection means, rotation speed detection means for detecting the rotation speed of the stirring blade, discharge amount detection means for detecting the discharge amount of the ground improvement material, and lifting action of the stirring blade by the lifting drive mechanism and discharge of the ground improvement material A control means for controlling the action is provided, and the control means calculates the blade cutting number ΔNs per unit length from the ascending / descending movement amount and the rotation speed of the stirring blade, and also the ascending / descending movement amount of the stirring blade and the soil improvement material. The discharge amount Δqs of the ground improvement material per unit length is calculated from the discharge amount, and every time the vertical movement amount reaches the unit length, a comparison between the calculated value ΔNs of the blade cutting times per unit length and the set value ΔN, And unit length The calculated value Δqs of the discharge amount of the ground improvement material is compared with the set value Δq, and the lifting operation to the next unit length is continued on condition that ΔNs ≧ ΔN and Δqs ≧ Δq are satisfied. A control device for a ground improvement machine characterized by the above.