JP5308405B2 - Support ground detection device and excavator using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide means to detect effective electric energy for accurately detecting bearing ground in the ground and means to discriminate whether or not a drilling rod reaches the bearing ground. <P>SOLUTION: Effective electricity energy detection means detects effective electric energy applied to a general purpose motor for drilling a unit volume of the ground. Bearing ground discrimination means discriminates that a drilling rod reaches a bearing ground when the effective electric energy detected by the effective electricity energy detection means reaches a prescribed value. <P>COPYRIGHT: (C)2012,JPO&amp;INPIT

Description

  The present invention relates to a supporting ground detection device and an excavator using the same. Specifically, a supporting ground detection device for detecting power supporting ground in the ground by excavating the ground with a drilling rod that is powered from a three-phase AC power source to a general-purpose motor and rotated by the general-purpose motor via a rotating shaft; The present invention relates to an excavator using the same.

Conventionally, a method for detecting a supporting ground, which is a strong supporting layer in the ground, is known. For example, this method is a method of excavating the ground with a drill rod having a drill head at the tip to form a pile hole, and the value of Ep obtained by the following (Equation 1) is a preset value or drilling A pile hole excavation method has been known in which, when the value is set during work, the ground is estimated as a support ground and a solidified portion of the pile hole is constructed (for example, Patent Document 1). Here, Aave1 is the mean integrated current value when drilling a depth L1 drilling speed v ₁ in a certain section, V is a auger voltage of the excavator. D is a pile hole diameter.
(Equation _{1) Ep = Aave1 × V /} (v 1 · D 2 · π / 4) [J / m3]

JP 2006-348515 A

  However, in the conventional pile hole excavation method, the excavation load current (integrated current value) is detected in order to obtain Ep, but this detected accumulated current is an apparent current, Reactive current not used for excavation is also included (apparent current detection method). In this apparent current detection method, if the power factor is low (the reactive current is large), the supporting ground in the ground cannot be accurately detected even if the integrated current value is converted into energy.

  In the conventional pile hole excavation method, the auger voltage V of the excavator is used as constant. However, in the excavator using the inverter, the voltage V is not constant in the region where the frequency f is low, It was not possible to accurately detect the supporting ground in the ground using 1). Furthermore, in an excavator in which two motors are controlled by independent inverters and are driven to rotate by the two motors, a phase difference occurs in the current and voltage flowing through each motor, and the above (Equation 1) It was not possible to detect the supporting ground in the ground even if was used.

  This invention is made | formed in view of the said problem, and it aims at providing the support ground detection apparatus which can detect the support ground in a ground correctly, and an excavator using the same.

次に、数式３を用いて、電流値（Ｉα、Ｉβ）と電圧値（Ｅα、Ｅβ）から単位掘削体積あたりの汎用モータに印加される瞬時有効電力Ｐを求め、

そして、数式４を用いて、有効電力量を検出するものである。
In order to solve the above problems and achieve the above object, the first aspect of the present invention is such that electric power is supplied from a three-phase AC power source to a general-purpose motor, and is rotated by the general-purpose motor via a rotating shaft. This is a support ground detection device that excavates the ground with an excavating rod and detects the support ground in the ground, and is effective in detecting the effective electric energy applied to the general-purpose motor per unit excavation volume based on the PQ method. Power amount detection means, and support ground determination means for determining that the excavation rod has reached the support ground when the active power amount detected by the effective power amount detection means reaches a predetermined value, The active energy detection means uses Equation 1 and Equation 2 to obtain an apparent current Iu that flows through the three-phase AC U phase, an apparent current Iv that flows through the V phase, and an apparent current Iw that flows through the W phase that are input to the general-purpose motor. And U phase Current value (Iα, Iβ) and voltage value (Eα, Eβ) are obtained from U-phase voltage Eu, V-phase voltage Ev of V-phase, and W-phase voltage Ew of W-phase,

Next, using Equation 3, the instantaneous active power P applied to the general-purpose motor per unit excavation volume is obtained from the current values (Iα, Iβ) and voltage values (Eα, Eβ),

Then, the amount of active power is detected using Equation 4 .

According to the present invention, based on the PQ method, it is determined that the excavation rod has reached the support ground when the effective electric energy per unit excavation volume detected by the active electric energy detection means becomes a predetermined value. Therefore, it is possible to accurately detect the supporting ground in the ground. That is, a change in the power actually used in the general-purpose motor is detected, and the excavation rod reaches the support ground when the effective power amount, which is the power actually used in the general-purpose motor, reaches a predetermined value. Therefore, it is possible to accurately detect the supporting ground in the ground.

  According to the second aspect of the present invention, there is provided a support ground detecting apparatus according to the first aspect, wherein the general-purpose motor is driven and controlled by an inverter.

  Even if a general-purpose motor is driven and controlled by an inverter, the excavation rod reaches the support ground when the effective electric energy per unit excavation volume detected by the active electric energy detection means reaches a predetermined value. Therefore, it is possible to accurately detect the supporting ground in the ground. That is, when the general-purpose motor is driven and controlled by the inverter, the voltage V also decreases along the frequency f in the region where the frequency f is low, but according to the present invention, the reduced voltage is also taken into consideration. Since the effective power amount is detected by the effective power amount detecting means, it is possible to accurately detect the supporting ground in the ground.

  Of the present invention, the third aspect is a support ground detection device according to the first aspect, excavating the ground with a drill rod that is driven to rotate by two general-purpose motors through a rotating shaft, A supporting ground detecting device for detecting a supporting ground in the ground, wherein each general-purpose motor is driven and controlled by an inverter provided corresponding to each general-purpose motor, and an active energy detection means is applied to each general-purpose motor. When the total value of the effective power amounts of the general-purpose motors detected by the effective power amount detecting means reaches a predetermined value, the support ground determining means detects the effective power amount. It is characterized by determining that the support ground has been reached.

  According to the present invention, even when the excavation rod is rotationally driven by two general-purpose motors that are driven and controlled by an inverter, the total amount of active power that is the electric power actually used by the two general-purpose motors is determined in advance. Since it is determined that the excavation rod has reached the support ground when the value reaches the value, the support ground in the ground can be accurately detected.

次に、数式３を用いて、電流値（Ｉα、Ｉβ）と電圧値（Ｅα、Ｅβ）から単位掘削体積あたりの汎用モータに印加される瞬時有効電力Ｐを求め、

そして、数式４を用いて、有効電力量を検出するものである。
In order to solve the above problems and achieve the above object, according to a fourth aspect of the present invention, electric power is supplied from a three-phase AC power source to a general-purpose motor, and is rotated by the general-purpose motor via a rotating shaft. This is a support ground detection device that excavates the ground with an excavating rod and detects the support ground in the ground, and is effective in detecting the effective electric energy applied to the general-purpose motor per unit excavation volume based on the PQ method. The power amount detecting means, the N value converting means for converting the active power amount detected by the active power amount detecting means into the N value of the standard penetration test, and the N value converted by the N value converting means are determined in advance. Support ground determination means for determining that the excavation rod has reached the support ground when the value reaches the value, and the active power amount detection means uses Equation 1 and Equation 2 to input the three Flow through phase U phase Current value (Iα) from the apparent current Iu, the apparent current Iv flowing through the V phase, the apparent current Iw flowing through the W phase, the U phase voltage Eu of the U phase, the V phase voltage Ev of the V phase, and the W phase voltage Ew of the W phase. , Iβ) and voltage values (Eα, Eβ),

Next, using Equation 3, the instantaneous active power P applied to the general-purpose motor per unit excavation volume is obtained from the current values (Iα, Iβ) and voltage values (Eα, Eβ),

Then, the amount of active power is detected using Equation 4 .

According to the present invention, there is provided N value conversion means for converting the active power amount per unit excavation volume detected by the active power amount detection means based on the PQ method into the N value of the standard penetration test, and the N value conversion Since it is determined that the excavation rod has reached the supporting ground when the N value converted by the means reaches a predetermined value, for example, the unit of hardness of the supporting ground is N value in accordance with national operational standards, etc. When defined by (number of times of driving at the time of testing), it is possible to accurately detect the supporting ground in the ground with a display that matches the operation standard. Thereby, for example, after the supporting ground is detected, the value of the N value can be used for the design of the foundation.

  A fifth aspect of the present invention relates to a support ground detection device according to the fourth aspect, wherein the ground is excavated with a drill rod that is driven to rotate by two general-purpose motors via a rotating shaft, A supporting ground detecting device for detecting a supporting ground in the ground, wherein each general-purpose motor is driven and controlled by an inverter provided corresponding to each general-purpose motor, and an active energy detection means is applied to each general-purpose motor. The active ground energy is detected, and the support ground determination means is configured such that when the total value of the N values of the general-purpose motors converted by the N value conversion means reaches a predetermined value, the excavation rod is placed on the support ground. It is characterized by determining that it has arrived.

  According to the present invention, even when the excavation rod is rotationally driven by two general-purpose motors that are driven and controlled by the inverter, the total value of the N values of the general-purpose motors converted by the N-value conversion means is a predetermined value. Therefore, it is determined that the excavation rod has reached the support ground, so that it is possible to accurately detect the support ground in the ground with a display that conforms to national operational standards.

  According to a sixth aspect of the present invention, there is provided a support ground detection device according to any one of the first to fifth aspects, a sun gear that rotates integrally with a rotating shaft that is rotated by a general-purpose motor, An internal gear that is coaxially disposed on the sun gear via a gap so as to cover the outer periphery of the sun gear, a planetary gear that is disposed in the gap and meshes with the sun gear and the internal gear, and is attached to the rotating shaft The excavating rod and the excavating blade attached to the internal gear are provided and excavated by the excavating rod and the excavating blade.

  According to the present invention, the sun gear that rotates integrally with the rotating shaft, the internal gear that is coaxially disposed in the sun gear via the gap so as to cover the outer periphery of the sun gear, and the gap that is disposed in the gap. Because it has a planetary gear that is installed and meshes with the sun gear and the internal gear, a drilling rod attached to the rotating shaft, and a drilling blade attached to the internal gear, while obtaining a large reduction ratio with a small number of gears The excavator can be excavated and the excavator can be downsized.

  According to the present invention, since it is determined whether the excavation rod has reached the support ground using the active power amount (or N value) per unit excavation volume, it is possible to accurately detect the support ground in the ground. it can.

(A) It is a top view of the excavator in which the support ground detection apparatus in one Embodiment of this invention was used. It is a side view of a X-axis direction. (B) Top view of the excavator. Side view in the Y-axis direction. (C) It is a top view of the excavator. It is AA sectional drawing of FIG.1 (b) and FIG.1 (c). It is BB sectional drawing of Fig.1 (a). It is a figure which shows the circuit diagram of the support ground detection apparatus in one Embodiment of this invention. It is a flowchart which shows the support ground detection process of the excavator using the support ground detection apparatus. It is the figure which graphed N value (total value) of the standard penetration test calculated | required by the N value conversion means. It is a figure which shows the circuit diagram of the support ground detection apparatus in the modification 1 of 1st embodiment of this invention. It is a figure which shows the circuit diagram of the support ground detection apparatus in the modification 2 of 1st embodiment of this invention. It is a figure which shows the circuit diagram of the support ground detection apparatus in the modification 3 of 1st embodiment of this invention. It is a figure which shows the circuit diagram of the support ground detection apparatus in 2nd embodiment of this invention. It is a figure which shows the circuit diagram of the support ground detection apparatus in the modification 1 of 2nd embodiment of this invention. It is a figure which shows the circuit diagram of the support ground detection apparatus in the modification 2 of 2nd embodiment of this invention. It is a circuit diagram of the support ground detection apparatus in the modification 3 of 2nd embodiment of this invention. (A) It is a top view of the excavator in which the support ground detection apparatus in 3rd embodiment of this invention was used. It is a side view of a X-axis direction. (B) Top view of the excavator. Side view in the Y-axis direction. (C) It is a top view of the excavator. It is CC sectional drawing of Fig.14 (a). It is DD sectional drawing of FIG. It is a figure which shows the excavation blade of the excavator in which the support ground detection apparatus in 3rd embodiment of this invention was used.

(First embodiment)
Hereinafter, an embodiment of a support ground detection device of the present invention will be described with reference to the drawings. 1A is a side view in the X-axis direction of a top view of the excavator in which the support ground detection device according to one embodiment of the present invention is used, and FIG. 1B is a top view of the excavator in the Y-axis direction. FIG. 1C is a top view of the excavator.

  As shown in FIG. 1 (a), an excavator 1 includes an upper case 2 having general-purpose motors 5a and 5b and a U-shaped (government-shaped) cross section, and fixing means such as bolts and pins to the upper case 2. A hollow middle case 3 fixed by (not shown) and a hollow lower case 4 fixed to the middle case 3 by fixing means (not shown) such as bolts and pins. A hollow lower member 7 is attached to the lower case 4.

  As will be described later, the output shaft (rotating shaft) 11 is rotated by general-purpose motors 5 a and 5 b and protrudes from the lower portion of the hollow lower member 7. A drilling rod (drill) 12 is attached to the output shaft 11 by fixing means (not shown) such as bolts and pins. When the fixing means referred to in the present embodiment is a bolt, a screw hole corresponding to the bolt may be provided on the fixed side, and a nut to be screwed with the bolt may be provided on the opposite side. The excavation rod 12 is hollow and has a circular cross section. By supplying cement milk or the like from the ground to a hollow portion (not shown) inside the excavation rod 12, the cement milk or the like is jetted from the tip of the excavation rod 12. Can be made. In this way, excavation rod 12 is excavated while being sequentially connected, and excavation rod 12 is inserted into the ground. In this embodiment, the excavation rods 12 are sequentially connected. However, the present invention is not limited to this, and excavation may be performed while connecting joints (not shown) to the excavation rod (drill) 12 at the tip.

  Next, the internal structure of the excavator 1 will be described with reference to FIG. 2 is a cross-sectional view taken along the line AA in FIGS. 1B and 1C, and FIG. 3 is a cross-sectional view taken along the line BB in FIG.

  General-purpose motors 5a and 5b composed of three-phase induction motors (induction motors) rotate motor rotating shafts 6a and 6b, and are respectively provided in the upper case 3 (see FIGS. 1A and 2). ). The general-purpose motors 5a and 5b are provided with a cooling fan (not shown) at the top, and the cooling fan (not shown) is configured to rotate from a fan drive shaft (not shown) of the general-purpose motors 5a and 5b. . This cooling fan (not shown) is provided on the upper part of the upper case 2. Thus, since the general-purpose motors 5a and 5b are provided with the cooling fans (not shown), the general-purpose motors 5a and 5b whose temperature has been increased by the rotation can be cooled.

  In this embodiment, for convenience of explanation, the motor rotation shaft 6 (6a, 6b) and the fan drive shaft (not shown) are described as separate members, but originally the motor rotation shaft 6 (6a, 6b). The fan drive shaft (not shown) is a rotating shaft of a general-purpose motor 5 (5a, 5b) integrally formed, and this rotating shaft is driven by the driving force of the general-purpose motors 5a, 5b.

  Electric motor gears 9a and 9b that are press-fitted using motor rotation shaft mounting bosses (motor rotation shaft mounting means (not shown)) are fixed to the motor rotation shafts 6a and 6b of the two general-purpose motors 5a and 5b, respectively. Yes. Thus, since the electric gears 9a and 9b are fixed to the motor rotation shafts 6a and 6b, they can rotate concentrically with the motor rotation shafts 6a and 6b.

  The input gear 10 is arranged so as to circumscribe the two motor gears 9a and 9b, and can be rotated by the rotation of the motor gears 9a and 9b (see FIGS. 2 and 3). An output shaft 11 press-fitted using an input shaft mounting boss (input shaft mounting means (not shown)) is fixed to the input gear 10.

  Next, a circuit diagram of the supporting ground detection device in the present embodiment will be described with reference to FIG. Here, FIG. 4 is a circuit diagram of the supporting ground detection device in one embodiment of the present invention. As described above, the inverters 8a and 8b provided corresponding to the two general-purpose motors 5a and 5b drive and control the general-purpose motors 5a and 5b, respectively.

  The support ground detection device 13 provided in the excavator 1 includes converter units 14a and 14b that convert an AC voltage from an AC power source (three-phase AC power source) into a DC voltage, and an output voltage from the converter units 14a and 14b. Capacitor parts 15a and 15b for smoothing, output bridge parts 16a and 16b for converting the DC voltage smoothed by the capacitor parts 15a and 15b into three-phase alternating current and outputting them to general-purpose motors (induction motors) 5a and 5b, A control device (not shown) for driving and controlling the output bridge portions 16a and 16b, inrush current suppression resistor portions 18a and 18b connected between the converter portions 14a and 14b and the capacitor portions 15a and 15b, and the inrush current suppression resistor The first switches 19a and 19b connected in parallel to the sections 18a and 18b, and one of the general-purpose motors 5a and 5b. 5b) and the capacitor unit 15 (15a or 15b) of the other general-purpose motor are connected in parallel, the second switch 20 connected in the parallel circuit, and the second switch 20 The discharge resistor 21 is connected in parallel to the parallel circuit provided with a third switch 22 connected to the parallel circuit provided with the discharge resistor 21. As shown in FIG. 4, inverters 8a and 8b are configured.

  The supporting ground detection device 13 includes U-phase current measuring devices 35a and 35b, W-phase current measuring devices 36a and 36b, a V-phase current calculator 23 (not shown), and U-phase to V-phase voltage measuring devices 37a and 37b. , V-phase to W-phase voltage measuring devices 38a and 38b, inter-phase to phase voltage converters 39a and 39b, active energy detection means 40 (not shown), and N value conversion means 41 (not shown). Yes.

First, the current measurement will be described. The U-phase current measuring devices 35a and 35b measure the apparent current Iu flowing through the U-phase, and the W-phase current measuring devices 36a and 36b measure the apparent current Iw flowing through the W-phase. It is to be measured. The V-phase current calculator 23 (not shown) calculates the apparent current value Iu flowing through the U-phase measured by the U-phase current measuring devices 35a and 35b and the W-phase measured by the W-phase current measuring devices 36a and 36b. The apparent current value Iv flowing through the V phase is calculated using the flowing apparent current value Iw. Specifically, since the sum of the apparent current Iu flowing through the U phase, the apparent current Iw flowing through the W phase, and the apparent current Iv flowing through the V phase becomes “0” (Iu + Iv + Iw = 0), this relational expression is used. The apparent current value Iv flowing through the V phase is obtained. In this embodiment, the V-phase current calculator 23 (not shown) is provided to obtain the apparent current value Iv flowing through the V-phase. ), A V-phase current measuring device (not shown) may be provided to measure the apparent current value Iv flowing through the V-phase. Needless to say, the apparent current value Iu, the apparent current value I _W , and the apparent current value _IV are determined in correspondence with the general-purpose motors 5a and 5b.

  Next, voltage measurement will be described. The U-phase to V-phase voltage measuring devices 37a and 37b measure the voltage between the U-phase and the V-phase, and the V-phase to W-phase voltage measuring devices 38a and 38b are The voltage between the phase and the W phase is measured. The phase-to-phase voltage converters 39a and 39b are measured by the U-phase to V-phase voltage measuring devices 37a and 37b and the V-phase to W-phase voltage measuring devices 38a and 38b. The U-phase voltage Eu, the V-phase voltage Ev, and the W-phase voltage Ew are obtained using the V-phase to W-phase voltage values. As a method for obtaining the U-phase voltage Eu, the V-phase voltage Ev, and the W-phase voltage Ew, for example, any one of the U-phase voltage Eu, the V-phase voltage Ev, and the W-phase voltage Ew is measured. The U-phase voltage Eu, the V-phase voltage Ev, and the W-phase voltage Ew are obtained using the V-phase voltage value and the V-phase to W-phase voltage value. Similar to the current, the U-phase voltage Eu, the V-phase voltage Ev, and the W-phase voltage Ew are also obtained corresponding to the general-purpose motors 5a and 5b.

The effective electric energy detection means 40 detects the effective electric energy applied to the motor rotation shafts 6a and 6b per unit excavation volume. The active energy detection means 40 includes an apparent current value Iu flowing through the U phase detected by the U phase current measuring devices 35a and 35b, and an apparent current value flowing through the W phase detected by the W phase current measuring devices 36a and 36b. I _W , apparent current value I _V flowing through V phase calculated by V phase current calculator 23 (not shown), U phase voltage Eu and V phase voltage converted by interphase-phase voltage converters 39a and 39b Using Ev and the W-phase voltage Ew, the effective electric energy applied to the general-purpose motors 5a and 5b per unit excavation volume is obtained. Specifically, first of all, using the following (Equation 1) and (Equation 2), the apparent current Iu flowing in the U phase and the apparent current flowing in the V phase in (Equation 1) and (Equation 2). Substituting the apparent current Iw flowing through Iv and W phase, U phase U phase voltage Eu, V phase V phase voltage Ev and W phase W phase voltage Ew, three-phase to two-phase conversion is performed. The instantaneous active power P and the instantaneous reactive power Q are obtained by substituting the current values (Iα, Iβ) and voltage values (Eα, Eβ) obtained by the conversion into (Equation 3) (PQ theory).

  In the present embodiment, for the convenience of explanation, the active power amount detection means 40 includes U-phase current measuring devices 35a and 35b, W-phase current measuring devices 36a and 36b, a V-phase current calculator 23 (not shown), and U The phase-V phase voltage measuring devices 37a, 37b, the V-phase-W phase voltage measuring devices 38a, 38b, and the U-phase-phase voltage converters 39a, 39b are described as separate configurations. Phase current measuring devices 35a, 35b, W phase current measuring devices 36a, 36b, V phase current calculator 23 (not shown), U phase-V phase voltage measuring devices 37a, 37b, V phase-W phase voltage measuring devices 38a, 38b and the phase-to-phase voltage converters 39a and 39b do not need to be configured separately from the active power amount detection means 40. Current value and voltage value, W-phase current Voltage ranging may be calculated a voltage value ranging current value of the V phase (same applies to other embodiments and variations, including the case of one general-purpose motor).

  Next, the active power P (n) is obtained. The effective power P (n) can be obtained by integrating the instantaneous active power P during excavation at a depth D (for example, 1 cm). Specifically, the support ground detection device 13 is provided with a depth measuring device (not shown). This depth measuring device (not shown) emits a depth measurement pulse every time the depth D (for example, 1 cm) is excavated by the excavating rod 12 of the excavator 1. Then, the effective power P (n) is obtained by integrating the instantaneous active power P supplied between the emitted depth measurement pulse and the previous depth measurement pulse.

  Note that after one active power P (n) is measured, the value is reset, and the instantaneous effective power P newly supplied between the next depth measurement pulse and the previous depth measurement pulse P. Is accumulated to obtain the active power P (n + 1). In the present embodiment, the active power P (n) is obtained directly from the instantaneous active power P supplied during the excavation at the depth D (for example, 1 cm). However, the present invention is not limited to this. Then, the high frequency may be suppressed using the digital LPF, and the active power P (n) may be calculated using the instantaneous active power P in which the high frequency is suppressed.

  Next, an effective power amount Pval (n) per unit excavation volume is obtained. Specifically, the effective power amount Pval (n) per unit excavation volume is obtained using (Equation 4). In this way, the effective power amount detecting means 40 detects the effective power amount Pval (n) applied to each general-purpose motor 5a, 5b per unit excavation volume. The effective power Pval (n) per unit excavation volume is detected by a control device in which the effective power amount detection means 40 is built. Here, D is an anti-hole diameter.

  In this embodiment, Pval (n) is used as the amount of active power applied to the general-purpose motors 5a and 5b per unit excavation volume, but the general-purpose motors 5a and 5b per unit excavation volume referred to in the present invention are used. The applied amount of active power is not limited to this, and may be, for example, a value obtained by multiplying Pval (n) by n times (integer multiple), an effective power amount obtained by processing the instantaneous active power P by another method, or the like. (The same applies to other embodiments and modifications including the case of one general-purpose motor).

  The N value conversion means 41 converts the active power amount Pval (n) detected by the active power amount detection means 40 into the N value of the standard penetration test. Here, the sum of the active electric energy val (n) applied to each of the general-purpose motors 5a and 5b is converted into an N value. Here, the standard penetration test refers to a test conducted to obtain the engineering properties (N value) and the sample of the ground defined in JIS A 1219. The N value of this standard penetration test is the hardness of soil Alternatively, it is an index indicating the relative value of the tightening degree, and is the number of hits required to drop a hammer of 63.5 kg from 75 cm freely and drive a standard penetration test sampler 30 cm. Specifically, the N value is obtained by (Equation 5). The N value is detected by a control device in which the N value conversion means 41 is built. Here, m is the mass of the hammer in the standard penetration test, h is the drop height of the hammer, S is the cross-sectional area of the cone, g is the acceleration of gravity, and N is the N value. In this embodiment, N obtained by (Equation 5) is used as an N value. However, the present invention is not limited to this. For example, a value obtained by multiplying N obtained by (Equation 5) by n (integer multiple). May be used as the N value (the same applies to other embodiments and modifications including one general-purpose motor).

  Next, operation | movement of the excavator using the support ground detection apparatus in this embodiment is demonstrated using FIG. 5 and FIG. Here, FIG. 5 is a flowchart showing a support ground detection step of the excavator in which the support ground detection device according to one embodiment of the present invention is used.

  As shown in FIG. 5, in the supporting ground detection step, first, it is determined in S1 whether the power switch (not shown) of the excavator 1 is ON. This power switch (not shown) is a main power source of the excavator 1, and a start switch (not shown) described later can be turned on by turning on the power switch (not shown). Here, if the power switch (not shown) is OFF, NO is determined in S1, and the process of S1 is performed until the power switch (not shown) is turned ON. If a power switch (not shown) is turned ON, YES is determined in S1, and the process proceeds to S2.

  In S2, it is determined whether a start switch (not shown) is ON. This start switch (not shown) is a switch for starting excavation by the excavator 1. That is, when this start switch (not shown) is turned ON, an alternating current is supplied, and the excavation rod 12 is rotated by the general-purpose motors 5a and 5b to start excavation. Here, if the start switch (not shown) is OFF, NO is determined in S2, and the process of S2 is performed until the start switch (not shown) is turned ON. If the start switch (not shown) is turned on, YES is determined in S2, and the process proceeds to S3. In this way, the excavation rod 12 is inserted into the ground by the driving force of the general-purpose motors 5a and 5b, and excavation is started (see S3). Then, the process proceeds to S4.

In S4, the effective power amount Pval (n) applied to the general-purpose motors 5a and 5b per unit excavation volume is detected (effective power amount detection step (active power amount detection means)). That is, in S4, the apparent current value Iu flowing through the U phase detected by the U phase current measuring devices 35a and 35b, and the apparent current value I _W flowing through the W phase detected by the W phase current measuring devices 36a and 36b, The apparent current value _IV flowing through the V phase calculated by the V phase current calculator 23 (not shown), the voltage between the U phase and the V phase measured by the U phase-V phase voltage measuring devices 37a and 37b, and the V phase. -U-phase voltage Eu, V-phase voltage Ev, and W-phase voltage obtained by inter-phase-to-phase voltage converters 39a, 39b using the voltage between V-phase and W-phase measured by W-phase voltage measuring instruments 38a, 38b Using each Ew, the effective electric energy val (n) applied to each general-purpose motor 5a, 5b per unit excavation volume is detected (see Equations 1 to 4). Here, in this embodiment, since the two general-purpose motors 5a and 5b are used, the effective power applied to the general-purpose motors 5a and 5b per unit excavation volume corresponding to the respective general-purpose motors 5a and 5b. The quantity Pval (n) is determined. Then, the process proceeds to S5.

  In S5, the total value of the effective electric energy Pval (n) per unit excavation volume obtained in S4 is converted into the N value of the standard penetration test (N value conversion process (N value conversion means)). Here, the N value is obtained using the above-described (Equation 5). In this embodiment, since two general-purpose motors 5a and 5b are used, the total value of N values corresponding to the respective general-purpose motors 5a and 5b is obtained. FIG. 6 is a graph showing the N value (total value) of the standard penetration test obtained by the N value conversion means. Then, the process proceeds to S6.

  In S6, it is determined whether the excavation rod 12 has reached the support ground (support ground determination step (support ground determination means)). This N value is an index indicating the relative value of soil hardness or firmness, and the hard ground has a higher N value. Therefore, in S6, when the N value becomes the support ground detection value K, the N value becomes the support ground. Judging that it has reached. When the N value (total value) obtained in S5 is equal to or smaller than the support base detection value K, NO is determined in S6, and S6 → S3 → S4 → S5 → S6 until the N value becomes the support base detection value K. This process is repeated. If it is determined in S6 that the N value has reached the support base detection value K, it is determined YES in S6, the process proceeds to S7, and a notification for notifying that the excavation rod 12 has reached the support ground is issued in S7. Done. This notification may be made by notifying that the excavation rod 12 has reached the support ground by voice, or may be notified by displaying it on a display (display means (not shown)). Then, the process proceeds to S8.

  In S <b> 8, the excavation rod 12 is lifted from the drilled hole excavated by the excavation rod 12. When the excavation rod 12 is pulled up, the process proceeds to S9, where the start switch (not shown) is turned off, and when the excavation is finished, the power switch (not shown) is turned off at S10. As described above, in this embodiment, Pval (n) is used as the amount of effective power applied to the general-purpose motors 5a and 5b per unit excavation volume, but the general-purpose per unit excavation volume referred to in the present invention. The amount of active power applied to the motors 5a and 5b is not limited to this, and is, for example, a value obtained by multiplying Pval (n) by n (integer multiple), an effective power amount obtained by processing the instantaneous active power P by another method, or the like. (The same applies to other embodiments and modifications including the case of one general-purpose motor.) In the present embodiment, N obtained in (Equation 5) is used as the N value. For example, a value obtained by multiplying N obtained by (Equation 5) by n (integer multiple) may be used as the N value (same in other embodiments and modifications including one general-purpose motor). In this case, of course, the value of the support base detection value K is changed according to each.

  As described above, the N value of the standard penetration test in which the active power amount Pval (n) per unit excavation volume detected by the active power amount detection means 40 is converted to the predetermined support base detection value K. Since it is sometimes determined that the excavation rod 12 has reached the support ground, it is possible to accurately detect the support ground in the ground. That is, a change in power actually used by the general-purpose motors 5a and 5b is detected, and an N value obtained by converting the effective power amount Pval (n) that is the power actually used by the general-purpose motors 5a and 5b is determined in advance. Since it is determined that the excavation rod 12 has reached the support ground when the detected support base detection value K is reached, the support ground in the ground can be accurately detected. In addition, since the N value is used, when the unit of hardness of the supporting ground is specified by the N value (number of times of driving during the test) according to the national operation standard, the display conforming to the operation standard is accurate. It is possible to detect the supporting ground in the ground. Thereby, for example, after the supporting ground is detected, the value of the N value can be used for the design of the foundation.

  Further, even if the general-purpose motors 5a and 5b are driven and controlled by the inverters 8a and 8b, the standard penetration converted from the effective power amount Pval (n) per unit excavation volume detected by the active power amount detection means 40. Since it is determined that the excavation rod 12 has reached the support ground when the N value of the test reaches a predetermined support base detection value K, the support ground in the ground can be accurately detected. That is, when the general-purpose motors 5a and 5b are driven and controlled by the inverters 8a and 8b, the voltage V also decreases along the frequency f in the region where the frequency f is low, but according to the present invention, the voltage V decreases. Considering the voltage, the effective power amount Pval (n) is detected by the effective power amount detecting means, so that the supporting ground in the ground can be detected accurately.

  Further, even when the excavation rod 12 is rotationally driven by the two general-purpose motors 5a and 5b that are driven and controlled by the inverters 8a and 8b, the effective power amount that is the electric power actually used by the two general-purpose motors 5a and 5b. Since it is determined that the excavation rod 12 has reached the support ground when the total value of the N values in the standard penetration test converted to Pval (n) reaches a predetermined value, the support ground in the ground is accurately determined. Can be detected.

(Modification 1)
Next, Modification 1 of the first embodiment of the present invention will be described with reference to the drawings. In the first modification and the first embodiment, the inverters (inverter devices) 8a and 8b are used in the first embodiment, whereas in the first modification, the inverter is not used and a three-phase AC power source is used. The difference is that power is directly supplied to the general-purpose motors 5a and 5b. FIG. 7 is a circuit diagram of the support ground detection device in Modification 1 of the first embodiment of the present invention. Thus, when the inverter is not used, the voltage supplied from the three-phase AC power source to the general-purpose motors 5a and 5b is the same between the two general-purpose motors 5a and 5b. The voltage supplied to the two general-purpose motors 5a and 5b can be measured by using the V-phase / W-phase voltage measuring device 38a and the inter-phase-phase voltage converter 39a. Accordingly, the voltage measuring instrument 37a and 37b between the U phase and the V phase, the voltage measuring instruments 38a and 38b between the V phase and the W phase, and the voltage measuring instrument and the voltage converter of any one of the phase-phase voltage converters 39a and 39b. Can be omitted (either a or b can be omitted). Since others are the same as that of 1st embodiment, description is abbreviate | omitted.

(Modification 2)
Next, Modification 2 of the first embodiment of the present invention will be described with reference to the drawings. In the second modification of the first embodiment, in the first embodiment, the excavation rod 12 is rotationally driven by the two general-purpose motors 5a and 5b, and the excavation rod 12 is rotationally driven by the single general-purpose motor 5a. It is a thing. FIG. 8 is a circuit diagram of a support ground detection device in Modification 2 of the first embodiment of the present invention. The modification 2 of the first embodiment is the same as the first embodiment except that the number of general-purpose motors 5a is one and the output shaft (rotary shaft) 11 is rotated by one general-purpose motor 5a.

  The support ground detection device 13 of Modification 2 of the first embodiment smoothes the output voltage from the converter unit 14a that converts an AC voltage from an AC power source (three-phase AC power source) into a DC voltage, and the converter unit 14a. Capacitor unit 15a, output bridge unit 16a that converts the DC voltage smoothed by capacitor unit 15a into three-phase AC and outputs the same to general-purpose motor (induction motor) 5a, and a control device that controls driving of output bridge unit 16a (Not shown), an inrush current suppression resistor portion 18a connected between the converter portion 14a and the capacitor portion 15a, a first switch 19a connected in parallel to the inrush current suppression resistor portion 18a, and a capacitor of the general-purpose motor 5a The discharge resistor 21 is connected to the second switch 20 connected in parallel with the section 15a and the parallel circuit provided with the second switch 20, and the discharge resistor 21 has a third switch 22 connected in parallel circuit provided. Moreover, the supporting ground detection apparatus 13 of the modification 2 of 1st embodiment is the U-phase current measuring device 35a, the W-phase current measuring device 36a, the V-phase current calculator 23 (not shown), and between the U-phase and V-phase. It has a voltage measuring instrument 37a, a V-phase / W-phase voltage measuring instrument 38a, an inter-phase-to-phase voltage converter 39a, an active energy detection means 40 (not shown), and an N value conversion means 41 (not shown). ing.

  The effective power amount detection means 40 detects the effective power amount Pval (n) applied to the general-purpose motor 5a per unit excavation volume. Here, the method for detecting the active power amount Pval (n) applied to the general-purpose motor 5a is obtained using (Equation 1) to (Equation 4), as in the first embodiment, and (Equation 5) is obtained. The active power amount Pval (n) detected by the active power amount detection means 40 is converted into the N value of the standard penetration test.

  After the N value is obtained by the N value conversion means 41, the N value of the general-purpose motor 5a and the support ground detection value K are compared to determine whether the excavation rod 12 has arrived on the support ground (S4). Thus, Modification 2 of the first embodiment has the same effect as the first embodiment.

(Modification 3)
Next, Modification 3 of the first embodiment of the present invention will be described with reference to the drawings. In the modification 3 and the modification 2 of the first embodiment, the inverter 8a is used in the modification 2 of the first embodiment, whereas the general-purpose motor is directly used from the three-phase AC power source without using the inverter in the modification 3. The place where power is supplied to is different. FIG. 9 is a circuit diagram of a support ground detection device in Modification 3 of the first embodiment of the present invention. As shown in FIG. 9, even when the inverter is not used, the U-phase current measuring device 35a, the W-phase current measuring device 36a, and the V-phase current calculator 23 (not shown) are the same as in the second modification of the first embodiment. ), A U-phase-V phase voltage measuring device 37a, a V-phase-W phase voltage measuring device 38a, an inter-phase-phase voltage converter 39a, an active energy detection means 40, and an N value conversion means 41 are used. The effective power amount Pval (n) and N value applied to the general-purpose motor 5a per unit excavation volume are obtained. The other detection methods of the supporting ground are the same as in Modification 2 of the first embodiment, and thus the description thereof is omitted.

(Second embodiment)
Next, a second embodiment of the present invention will be described with reference to the drawings. The first embodiment is different from the second embodiment in the way of obtaining the instantaneous effective power P, and the rest is the same as the first embodiment. The following description will focus on the differences from the first embodiment, and the description of the same parts as in the first embodiment will be omitted. FIG. 10 is a circuit diagram of the supporting ground detection device in the second embodiment of the present invention.

  In the second embodiment, voltage measuring devices 37a and 37b for measuring the voltage between the U phase and the V phase, current measuring devices 36a and 36b for measuring the current flowing through the W phase, the voltage value between the U phase and the V phase, and the W phase are obtained. Using a computer (not shown) that calculates the active power using the flowing current value, the U-phase to V-phase voltages of the general-purpose motors 5a and 5b made of a three-phase induction motor and the current flowing through the W phase are measured. The active power amount Pval (n) flowing through the general-purpose motors 5a and 5b is obtained. By doing in this way, a current measuring device and a voltage measuring device can be decreased.

  Next, a method for detecting the active power amount Pval (n) will be described. Since the phase difference between the U-phase and V-phase voltages of the general-purpose motors 5a and 5b and the current flowing through the W-phase measured as described above is π / 2, the range of π / 2 to 3π / 2 of these waveforms Is integrated to obtain the effective power P corresponding to the instantaneous effective power P of the first embodiment. Here, in the present embodiment, the range of π / 2 to 3π / 2 is integrated. However, the present invention is not limited to this, and the active power P is obtained by integrating in the range of π / 2 + 2nπ to 3π / 2 + 2nπ (n is an integer). May be. In the present embodiment, Hall element type current measuring devices having flat characteristics in a frequency band of about 5 Hz to 150 Hz are used as the current measuring devices 36a and 36b. Then, as in the first embodiment, the effective power P (n) is obtained by integrating the effective power P supplied during excavation at the depth D (for example, 1 cm), and the effective power is calculated using (Equation 4). The amount Pval (n) is obtained, and the active power amount Pval (n) detected by the active power amount detecting means 40 is converted into the N value of the standard penetration test using (Equation 5). In the present embodiment, the depth D is 1 cm, for example. However, the depth D is not limited to this, and may be 10 cm, or other depths may be used. In particular, in this embodiment, since the active power P is obtained by integrating the range of π (π / 2 to 3π / 2) of the above waveform, the time for which the depth D excavation is sufficiently longer than the period of this waveform It is desirable that Since others are the same as that of 1st embodiment, description is abbreviate | omitted.

(Modification 1)
Next, Modification 1 of the second embodiment of the present invention will be described with reference to the drawings. In the first modification of the second embodiment and the second embodiment, the inverters (inverter devices) 8a and 8b are used in the second embodiment, whereas in the first modification of the second embodiment, no inverter is used. The difference is that power is supplied directly from a three-phase AC power supply to a general-purpose motor. FIG. 11 is a circuit diagram of a support ground detection device in Modification 1 of the second embodiment of the present invention. Thus, when the inverter is not used, the voltage supplied from the three-phase AC power source to the general-purpose motors 5a and 5b is the same between the two general-purpose motors 5a and 5b. Can be used to measure the voltage between the U-phase and V-phase supplied to the two general-purpose motors. Thereby, any one of the U-phase-V phase voltage measuring devices 37a and 37b can be omitted (either a or b is omitted). Since others are the same as that of 2nd embodiment, description is abbreviate | omitted.

(Modification 2)
Next, Modification 2 of the second embodiment of the present invention will be described with reference to the drawings. In the second modification of the second embodiment, in the second embodiment, the excavation rod 12 is rotationally driven by the two general-purpose motors 5a and 5b so that the excavation rod 12 is rotationally driven by the single general-purpose motor 5a. It is a thing. FIG. 12 is a circuit diagram of a support ground detection device in Modification 2 of the second embodiment of the present invention. The second modification of the second embodiment is the same as the second embodiment except that the number of general-purpose motors 5a is one and the output shaft (rotary shaft) 11 is rotated by one general-purpose motor 5a. The description is omitted.

  The support ground detection device 13 of Modification 2 of the second embodiment smoothes the output voltage from the converter unit 14a that converts an AC voltage from an AC power source (three-phase AC power source) into a DC voltage, and the converter unit 14a. Capacitor unit 15a, output bridge unit 16a that converts the DC voltage smoothed by capacitor unit 15a into three-phase AC and outputs the same to general-purpose motor (induction motor) 5a, and a control device that controls driving of output bridge unit 16a (Not shown), an inrush current suppression resistor portion 18a connected between the converter portion 14a and the capacitor portion 15a, a first switch 19a connected in parallel to the inrush current suppression resistor portion 18a, and a capacitor of the general-purpose motor 5a The discharge resistor 21 is connected to the second switch 20 connected in parallel with the section 15a and the parallel circuit provided with the second switch 20, and the discharge resistor 21 has a third switch 22 connected in parallel circuit provided. Further, the support ground detection device 13 of the second modification of the second embodiment includes a W-phase current measuring device 36a, a U-phase / V-phase voltage measuring device 37a, an active energy detection means 40 (not shown), N It has value conversion means 41 (not shown).

  The effective power amount detection means 40 detects the effective power amount Pval (n) applied to the general-purpose motor 5a per unit excavation volume. Here, the method of detecting the active power amount Pval (n) applied to the general-purpose motor 5a is obtained using (Equation 4) and the active power amount using (Equation 5), as in the second embodiment. The active power amount Pval (n) detected by the detection means 40 is converted into an N value of the standard penetration test.

  After the N value is obtained by the N value conversion means 41, the N value of the general-purpose motor 5a and the support ground detection value K are compared to determine whether the excavation rod 12 has reached the support ground (S4). Thus, Modification 2 of the second embodiment has the same effect as that of the first embodiment.

(Modification 3)
Next, Modification 3 of the second embodiment of the present invention will be described with reference to the drawings. In Modification 3 and Modification 2 of the second embodiment, the inverter 8a is used in Modification 2 of the second embodiment, whereas in Modification 3, a general-purpose motor is directly used from a three-phase AC power source without using an inverter. The place where power is supplied to is different. FIG. 13 is a circuit diagram of a support ground detection device in Modification 3 of the second embodiment of the present invention. As shown in FIG. 13, even when the inverter is not used, the W-phase current measuring device 36a, the U-phase / V-phase voltage measuring device 37a, and the active energy detecting means 40 are the same as in the second modification of the second embodiment. Then, the N value conversion means 41 is used, and the effective power amount Pval (n) and the N value applied to the general-purpose motor 5a per unit excavation volume are obtained. Since the other detection methods of the supporting ground are the same as in Modification 2 of the second embodiment, description thereof is omitted.

(Third embodiment)
Hereinafter, a third embodiment of the present invention will be described with reference to the drawings. FIG. 14A is a side view in the X-axis direction of the top view of the excavator in which the support ground detection device according to the third embodiment of the present invention is used, and FIG. 14B is a top view of the excavator in the Y-axis direction. FIG. 14C is a top view of the excavator.

  The difference between the third embodiment of the present invention and the first embodiment and the second embodiment is that the inside of the lower case 4 of the first embodiment and the second embodiment is hollow, In the third embodiment, the planetary gear device 24 is provided inside the lower case 4 and excavated by the excavating rod 12 attached to the output shaft 11 and attached to the internal gear 25 of the planetary gear device 24 via the lower member 7. The excavating blade 26 can be excavated. In FIG. 14, the excavation rod 12 attached to the output shaft 11 is omitted, but excavation is performed with the excavation rod 12 in the third embodiment as in the first and second embodiments. This will be specifically described below.

  As shown in FIG. 14, the excavation blade 26 is attached to the lower member 7 by fixing means (not shown) including bolts and nuts.

  Next, the planetary gear device 24 provided in the lower case 4 will be described. Here, FIG. 15 is a CC cross-sectional view of FIG. 14A, and FIG. 16 is a DD cross-sectional view of FIG.

  As shown in FIGS. 14 and 15, the planetary gear device 24 includes a sun gear 27 press-fitted to the output shaft 11 (rotary shaft) using a sun gear mounting boss (sun gear mounting means (not shown)), The sun gear 27 is arranged in a space between the sun gear 27 and the internal gear 25 so as to cover the outer periphery of the sun gear 27, and the sun gear 27 is arranged coaxially via the space. And a planetary gear 28 that meshes with the internal gear 25 and rotates around the sun gear 27. A plurality of planetary gears 28 (three in this embodiment) are arranged at equal intervals around the sun gear 27 arranged on the rotation shaft.

  The sun gear 27 includes a substantially cylindrical gear portion 29 having teeth formed on the outer peripheral surface, and a fitting portion 30 that has a smaller diameter than the gear portion 29 and is fitted to the output shaft 11. The gear portion 29 is configured to mesh with the planetary gear 28, and the fitting portion 30 rotates integrally with the output shaft 11 by fitting with the fitting portion 31 of the output shaft 11.

  Each planetary gear 28 is formed with a through hole 32 penetrating in the axial direction in the central portion, and can rotate around a pin 34 inserted into the through hole 32. Here, the planetary gear 28 is inserted into the pin 34 via a needle bearing (not shown). The pin 34 is rotatably attached to a casing 51 formed integrally with the lower case 4 via a needle bearing (not shown).

  The internal gear 25 is rotatably attached to the lower case 4 via a bearing 50. Thus, each planetary gear 28 rotates around the pin 34 as the sun gear 27 rotates, and the internal gear 25 can be rotated by the rotation of the planetary gear 28.

  The lower member 7 is attached to the internal gear 25 by fixing means such as a bolt 52. Further, as described above, the excavating blade 26 (see FIG. 17) is attached to the internal gear 25 via the lower member 7. Thus, the excavating blade 26 can rotate at the same rotational speed as the internal gear 25 via the lower member 7 as the internal gear 25 rotates, and the circular hole is excavated as the excavating blade 26 rotates. be able to. And inside this circular hole, it is excavated while scraping up the soil with the excavating rod 12 inside the excavating blade 26, and a cylindrical hole can be formed. In this manner, excavation is performed while the joints of the excavation blades 26 are sequentially connected, and the excavation blades 26 are inserted into the ground. In the present embodiment, the aspect in which the excavating blade 26 is attached to the internal gear 25 via the lower member 7 is shown, but the present invention is not limited to this, and the excavating blade 26 may be directly attached to the internal gear 25. That is, the excavation blade 26 may be attached to the internal gear 25 directly or indirectly. Here, FIG. 17 is a diagram showing an excavating blade of an excavator in which the support ground detecting device according to the third embodiment of the present invention is used.

  As described above, the planetary gear device 24 is provided, and the excavating blade 26 is provided on the internal gear 25 of the planetary gear device 24, so that excavation can be performed while obtaining a large reduction ratio with a small number of gears. Miniaturization can also be achieved.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. Further, the scope of the present invention is shown not by the above description but by the description of the scope of claims, and is intended to include all modifications within the meaning and scope equivalent to the scope of claims.

Next, a modified example will be described.
(1) In the first to third embodiments (including modifications), the effective power amount Pval (n) applied to the general-purpose motors 5a and 5b per unit excavation volume is detected by S4 in FIG. , S5 converts the effective electric energy Pval (n) (total value) per unit excavation volume into the N value of the standard penetration test, and when the N value becomes the support ground detection value K by S6. Although it is determined that the support ground has been reached, the present invention is not limited to this, and the effective power amount Pval (n) applied to the general-purpose motors 5a and 5b per unit excavation volume is detected by S4, and the unit is designated as S5 and S6. It is determined that the excavation rod 12 has reached the support ground when the effective power amount Pval (n) per excavation volume (the total value when there are two general-purpose motors) reaches the predetermined support ground detection value KK. Shi May be. In other words, the N value is (0.3S / mgh) times (a constant multiple) times the active power amount Pval (n) applied to the general-purpose motors 5a and 5b per unit excavation volume detected by S4. By multiplying the ground detection value KK by (mgh / 0.3S) the support ground detection value K, the effective electric energy applied to the general-purpose motor per unit excavation volume (the total value when there are two general-purpose motors) By using it, it can be determined whether the excavation rod 12 has reached the support ground.

DESCRIPTION OF SYMBOLS 1 Excavator 2 Upper case 3 Middle case 4 Lower case 5a, 5b General-purpose motor 6a, 6b Motor rotating shaft 7 Lower member 8a, 8b Inverter 9a, 9b Electric gear 10 Input gear 11 Output shaft 12 Excavation rod 13 Support ground detection apparatus 14a , 14b Converter unit 15a, 15b Capacitor unit 16a, 16b Output bridge unit 17 Controller 18a, 18b Inrush current suppression resistor unit 19a, 19b First switch 20 Second switch 21 Discharge resistor 22 Third switch 23 V-phase current calculator 24 Planetary gear mechanism 25 Internal gear 26 Excavation blade 27 Sun gear 28 Planetary gear 29 Gear portion 30 Fitting portion 31 Fitting portion 32 Through hole 34 Pins 35a, 35b U-phase current measuring devices 36a, 36b W-phase current measuring devices 37a, 37b U-V phase voltage measuring instrument 38a, 38b V-W phase voltage measuring instrument 39a 39b Interphase-phase voltage converter 40 Active energy detection means 41 N value conversion means 50 Bearing 51 Casing 52 Bolt

Claims (6)

A support ground detection device for detecting power support ground in the ground by excavating the ground with a drill rod that is powered by a three-phase AC power supply to a general-purpose motor and rotated by the general-purpose motor via a rotating shaft,
Based on the PQ method, effective power amount detecting means for detecting an effective power amount applied to the general-purpose motor per unit excavation volume;
Support ground determination means for determining that the excavation rod has reached the support ground when the active power amount detected by the active power amount detection means reaches a predetermined value ;
The active energy detection means uses Equations 1 and 2 to obtain an apparent current Iu that flows through the three-phase AC U phase, an apparent current Iv that flows through the V phase, and an apparent current that flows through the W phase that are input to the general-purpose motor. Current values (Iα, Iβ) and voltage values (Eα, Eβ) are obtained from Iw, U phase U phase voltage Eu, V phase V phase voltage Ev, and W phase W phase voltage Ew,

Next, using Formula 3, the instantaneous active power P applied to the general-purpose motor per unit excavation volume is obtained from the current values (Iα, Iβ) and voltage values (Eα, Eβ),

And the supporting ground detection apparatus characterized by detecting active electric energy using Numerical formula 4 .   The support ground detection device according to claim 1, wherein the general-purpose motor is driven and controlled by an inverter. A support ground detection device that detects a support ground in the ground by excavating the ground with a drill rod that is rotationally driven by two general-purpose motors via a rotating shaft,
Each general-purpose motor is driven and controlled by an inverter provided corresponding to each general-purpose motor,
The active power amount detecting means detects an effective power amount applied to each general-purpose motor,
The supporting ground determining means determines that the excavation rod has reached the supporting ground when the total value of the effective electric energy of each general-purpose motor detected by the active electric energy detecting means reaches a predetermined value. The supporting ground detection device according to claim 1, wherein A support ground detection device for detecting power support ground in the ground by excavating the ground with a drill rod that is powered by a three-phase AC power supply to a general-purpose motor and rotated by the general-purpose motor via a rotating shaft,
Based on the PQ method, effective power amount detecting means for detecting an effective power amount applied to the general-purpose motor per unit excavation volume;
N value conversion means for converting the active power amount detected by the active power amount detection means to the N value of the standard penetration test;
Support ground judgment means for judging that the excavation rod has reached the support ground when the N value converted by the N value conversion means reaches a predetermined value;
The active energy detection means uses Equations 1 and 2 to obtain an apparent current Iu that flows through the three-phase AC U phase, an apparent current Iv that flows through the V phase, and an apparent current that flows through the W phase that are input to the general-purpose motor. Current values (Iα, Iβ) and voltage values (Eα, Eβ) are obtained from Iw, U phase U phase voltage Eu, V phase V phase voltage Ev, and W phase W phase voltage Ew,

Next, using Formula 3, the instantaneous active power P applied to the general-purpose motor per unit excavation volume is obtained from the current values (Iα, Iβ) and voltage values (Eα, Eβ),

And the supporting ground detection apparatus characterized by detecting active electric energy using Numerical formula 4 . A support ground detection device that detects a support ground in the ground by excavating the ground with a drill rod that is rotationally driven by two general-purpose motors via a rotating shaft,
Each general-purpose motor is driven and controlled by an inverter provided corresponding to each general-purpose motor,
The active power amount detecting means detects an effective power amount applied to each general-purpose motor,
The supporting ground determining means determines that the excavation rod has reached the supporting ground when the total value of the N values of the general-purpose motors converted by the N value converting means reaches a predetermined value. The support ground detection device according to claim 4 characterized by things. A sun gear that rotates integrally with a rotating shaft that is rotated by the general-purpose motor;
An internal gear coaxially disposed in the sun gear via a gap so as to cover the outer periphery of the sun gear;
A planetary gear disposed in a gap and meshing with the sun gear and the internal gear;
A drilling rod attached to the rotating shaft;
A drilling blade attached to the internal gear,
The excavator using the support ground detection device according to any one of claims 1 to 5, wherein excavation is performed by the excavation rod and the excavation blade.

Images