Rod rotation drive device and ground improvement machine

Abstract

To provide a ground improvement machine comprising a rod rotation drive device and the rod rotation drive device capable of reliably determining a chuck state of a rod.SOLUTION: A rod chuck mechanism 23 provided in a rod rotation drive device has a pair of left and right chuck plates 34, 34 that engage with an outer peripheral surface of a rod 19, chuck means (spring) that moves both chuck plates in the radial direction of the rod to close them, a wireless switch 36 that operates when the amount of movement of the chuck plate exceeds a preset threshold value. The wireless switch includes a transmission unit that emits a wireless signal, and is attached to a drive shaft 31 via a bracket 33. In addition, a ground improvement machine comprising the rod rotation drive device comprises a reception unit that performs wireless communication with the transmission unit, and a notification unit that notifies the open / closed state of the chuck plate based on the wireless signal received by the reception unit.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to a rod rotation drive device and a ground improvement machine, and more particularly, to a rod rotation drive device that is arranged to be able to rise and fall along a leader erected at the front of a base machine, and a ground improvement machine equipped with a rod rotation drive device. [Background technology]

[0002] Conventionally, a rod rotation drive device (auger) used in a ground improvement machine is known that includes a drive unit body equipped with a rotation drive source such as a hydraulic motor or a reducer, a rod rotation part (output shaft) having a square hole into which a square shaft part provided on a rod can be inserted and engaged, and a chuck plate that can be engaged with a circumferential groove part provided on the lower part of the square shaft, and is rotatable together with the drive unit body. The chuck plate is engaged with the rod rotation part by the force of a spring, and this fixation is released by pressing a cone-shaped chuck release member into a receiving part of the cone-shaped chuck release member provided on the chuck plate and pushing the chuck plate apart against the force of the spring (for example, see Patent Document 1).

[0003] The ground improvement machine is also equipped with a construction management device that stores a construction management program for controlling the construction method. When the construction management device pushes the rod into the ground, it executes the construction management program using a control device (control box) installed in the driver's cab, obtains data from multiple sensors installed in various parts such as the reader and the rod rotation drive device, and obtains depth, speed, torque, rotation speed, etc. from the data, displays them on a display, and records them in memory while performing construction (see, for example, Patent Document 2). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 7-189576 [Patent Document 2] JP 2004-250956 A Summary of the Invention [Problem to be solved by the invention]

[0005] The construction management system described in Patent Document 2 is useful in that it can perform accurate depth management by correcting the depth error caused by the sinking of the rod when the rod is replaced (when the chuck is released). However, in order to perform the depth correction process, it is necessary to cancel the stopped state of the depth measurement every time work is resumed, which is not necessarily convenient for the operator of the ground improvement machine. Moreover, since it is not easy to visually check the state of the chuck located at a high position from the driver's cab, there is a risk that after the chuck closing operation, the operator will perform the release operation without noticing that the chuck plate is not fitted into the groove of the rod, and continue working as it is.

[0006] Therefore, an object of the present invention is to provide a rod rotation drive device that can reliably determine the chuck state of the rod, and a ground improvement machine equipped with the rod rotation drive device. [Means for solving the problem]

[0007] In order to achieve the above object, the rod rotation drive device of the present invention includes a drive device main body having a rotatable drive shaft having a rod insertion hole, a rod chuck mechanism provided on the drive shaft so as to be rotatable integrally with the drive shaft, and a chuck release mechanism corresponding to the rod chuck mechanism, wherein the rod chuck mechanism includes a pair of left and right chuck members that engage with an outer peripheral surface of a rod, chuck means for moving both chuck members in the rod radial direction to close the chuck members, The movement of the chuck member is directly detected, a wireless switch that is activated when the amount of movement of the chuck member exceeds a preset threshold value, the wireless switch having a transmitting unit that emits a wireless signal, Can rotate together with The present invention is characterized by being attached to the

[0008] In addition, the ground improvement machine of the present invention is characterized in that, in a ground improvement machine equipped with the rod rotation drive device, it is equipped with a receiving unit that performs wireless communication with the transmitting unit, and an alarm unit that alarms the open / closed state of the chuck member based on the wireless signal received by the receiving unit. Effect of the Invention

[0009] According to the rod rotation drive device of the present invention, a wireless switch is used as a detection means for detecting the movement of the chuck member, and therefore, an attachment structure to the rotating part that utilizes the wireless characteristics is achieved. This makes it possible to directly detect the movement of the chuck member, and the chuck state of the rod can be determined reliably. In addition, according to the ground improvement machine of the present invention, a notification unit is provided that notifies the open / closed state of the chuck member based on a signal from the wireless switch, so that when determining the chuck state of the rod, the notification unit can be assisted in addition to visual confirmation, which contributes to safe and secure work for the operator.

[0010] In particular, the simple configuration consisting of a wireless switch and an associated communication module (receiver) reduces the amount of wiring required for the control circuit, making it easier to connect to existing construction management systems. Therefore, even if the depth measurement needs to be temporarily stopped when the rod is replaced, this temporary stop function can be linked based on accurate operation information from the chuck member, eliminating the need to provide a separate release switch as in Patent Document 2. In other words, there is no need to rely on a configuration that requires the driver to operate the release switch or on software processing to deal with forgetting to release the switch, which contributes to improving the reliability of the construction management system. [Brief description of the drawings]

[0011] [Figure 1] 1 is a side view of a ground improvement machine to which a rod rotation drive device is applied, showing one embodiment of the present invention. [Diagram 2] FIG. [Diagram 3]FIG. 4 is a cross-sectional front view of a main portion showing a chucked state of the rod. [Figure 4] FIG. 4 is a cross-sectional front view of a main portion showing a state in which the rod is released from the chuck. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] 1 to 4 show an example of the rod rotation drive device of the present invention. As shown in FIG. 1, a ground improvement machine 11 to which the rod rotation drive device of the present invention is applied has a leader 15 erected at the front of a base machine 14 composed of a lower traveling body 12 traveling on a track and an upper rotating body 13 rotatably provided on the lower traveling body 12, and the leader 15 is supported by a backstay 16. A pair of left and right guide pipes 15a provided along the longitudinal direction of the leader 15 are connected to a rod rotation drive device (auger) 17 via a guide gib 18, and are provided so as to be able to rise and fall by a chain 15b hung in the longitudinal direction of the leader 15. In addition, a lower guide 20 is provided at the bottom of the leader 15 to guide a rod 19 rotated by the rod rotation drive device 17. Furthermore, a driver's cab 21 is provided on the right side of the upper rotating body 13, and an equipment room 22 containing an engine and a hydraulic unit is provided on the left side.

[0013] The rod 19 is a hollow tube through which a soil improvement agent such as cement milk can be inserted, and as shown in Fig. 2, it has square shafts 19b with grooves 19a with circular cross sections at multiple locations along its length, which engage with a rod chuck mechanism 23 provided on the underside of the rod rotation drive device 17, and a drilling head 24 equipped with a drilling blade 24a and agitation blades 24b at its lower end. A swivel joint 26 for introducing soil improvement agent from an injection hose (grout hose) 25 is provided at the upper end of the rod 19. One end of a rotation-stopping rod 27 for preventing the swivel joint 26 from rotating is fixed to the rod rotation drive device 17, and the other end is attached to a mounting member 28 provided at the upper end of the rod 19.

[0014] To perform ground improvement work using the ground improvement machine 11, the rod 19 is inserted into the driving device body (reduction mechanism) 29 of the rod rotation driving device 17, and the groove portion 19a of the rod 19 is engaged with the rod chuck mechanism 23 to restrict the axial movement of the rod 19. In this state in which the middle portion of the rod 19 is gripped, the rod 19 is held rotatably and vertically movable by the lower guide 20, and an injection hose 25 is connected to a swivel joint 26 at the upper end of the rod 19 (FIG. 1). In this work start state, the driving device body 29 is driven by the rotation drive hydraulic motor 30, and the rod 19 is rotated and lowered along the leader 15, and the soil improvement agent sent through the rod 19 is sprayed from the tip of the excavation head 24 into the excavation hole, so that the soil excavated by the excavation blade 24a of the excavation head 24 and the soil improvement agent are mixed by the mixing blade 24b.

[0015] When the rod rotation drive device 17 reaches the lower end of the leader 15, the rod rotation drive device 17, which has released its grip on the middle part, is raised and the upper part is gripped. At this time, the rod 19 is gripped by the fixing means of the lower guide 20 in order to fix the rod 19 in that position. When the gripping position of the rod 19 is switched to the upper side by the movement of the rod rotation drive device 17, the rod 19 is again lowered while being rotated, and the soil excavated by the excavation blade 24a and the ground improvement agent are mixed by the mixing blade 24b. Then, after the excavation head 24 is lowered to a predetermined depth, the excavation head 24 is raised in the reverse order, completing the ground improvement work.

[0016] To perform such ground improvement work, devices such as operating levers, operating pedals, and push button switches for traveling, turning, and raising / lowering / rotating the rod rotation drive device 17 are concentrated near the driver's seat in the driver's cab 21 for ease of operation, and a construction management device is also installed that is electrically connected to these devices and the operation detection means of the ground improvement machine 11. The construction management device is composed of a control unit that executes a construction management program for controlling the construction method based on detection signals from each detection means and information input by the driver, and a touch panel display on which the driver can check the processing results of the construction management program and enter data.

[0017] Here, in order to smoothly carry out the ground improvement work, the rod rotation drive device 17 is required to have a function of reliably transmitting the necessary rotation torque and thrust force to the rod 19 and performing appropriate construction management. The specific configuration of the rod rotation drive device 17 will be described below with reference to Figs. 2 to 4.

[0018] The rod rotation drive device 17 has a drive shaft 31 rotatably provided inside a drive device main body 29, and a rod insertion hole 31a having a hexagonal cross section is formed inside the drive shaft 31 in the vertical direction, and the angular shaft portion 19b of the rod 19 is inserted and engaged into the rod insertion hole 31a. A cylindrical portion 31b is formed at the lower end of the drive shaft 31, and a rod chuck mechanism 23 that rotates integrally with the drive shaft 31 is provided at the lower end of the cylindrical portion 31b, and a chuck release mechanism 32 is provided between the lower surface of the drive device main body 29 and the rod chuck mechanism 23.

[0019] The rod chuck mechanism 23 is composed of a frame-shaped bracket 33 provided at the lower end of the cylindrical portion 31b, a pair of left and right chuck plates 34, 34 as chuck members arranged opposite each other and movably in the radial direction of the rod (horizontal direction) within the bracket 33, and a total of four springs 35, 35 in two rows at the front and back and two rows at the top and bottom (the opposite side is not shown) as a chuck means for closing both chuck plates 34, 34.

[0020] 3 and 4, the bracket 33 is a flattened square pipe with a rod insertion hole 33a formed in the center, and a wireless switch 36, which is one of the operation detection means, is attached to a mounting seat 33b provided on the underside of one side. Each chuck plate 34, 34 has a semicircular notch 34a at its inner end that engages with the groove 19a of the rod 19, and although not shown, a guide pin inserted in the bracket 33 passes through an elongated hole provided on both sides, so that the chuck plate 34 can move in the radial direction of the rod inside the bracket 33. Springs 35, 35 are stretched on both ends of the chuck plates 34, 34 that protrude from both outer ends of the bracket 33, respectively, and urge the chuck plates 34, 34 in the closing direction.

[0021] The chuck release mechanism 32 is composed of a pair of left and right chuck cylinders 38, 38 and springs 39, 39 arranged alternately front to back via a slide device 37 on both left and right sides (non-rotating parts) of the drive unit main body 29, a cone-shaped chuck release member 40 supported so that it can be raised and lowered by the chuck cylinder 38 and spring 39, and crescent-shaped rings 41, 41 provided on the upper surface sides of the ends of chuck plates 34, 34 which protrude from both outer ends of the bracket 33, respectively.

[0022] Cone-shaped chuck release member 40 is formed in a hollow inverted cone shape with a smaller diameter at the tip side of the lower part than at the upper part, and the cylindrical portion 31b is disposed through cone-shaped chuck release member 40. When chuck cylinder 38 is in the contracted state, half-moon shaped rings 41, 41 are disposed apart from the tip of cone-shaped chuck release member 40 and are disposed at a distance between both rings 41, 41 such that the tip of cone-shaped chuck release member 40 can be inserted therebetween.

[0023] Furthermore, the crescent-shaped rings 41, 41 are attached to stays 34b provided on the upper surface of the end of the chuck plate 34 protruding from the outer end of the bracket 33, and the body 40a of the cone-shaped chuck release member 40, which descends as the chuck cylinder 38 extends, engages with the inner peripheral sides of both rings 41, 41, widening the gap between both rings 41, 41 and functioning as a thrust conversion mechanism that converts the vertical force caused by the extension of the chuck cylinder 38 into a horizontal force, thereby moving both chuck plates 34, 34 in the opening direction. For this reason, the inner peripheral sides of the crescent-shaped rings 41, 41 are provided with an inclination that is approximately the same as the inclination of the body 40a of the cone-shaped chuck release member 40.

[0024] The wireless switch 36 is a limit switch (roller arm type) that is actuated by the rotation of the arm 36a in contact with the chuck plate 34. The arm 36a is adjusted to a set angle corresponding to the movement of the chuck plate 34 at the initial position before actuation, and is close enough to the outer end of the chuck plate 34 in the closed state to eliminate any gap, as shown in FIG. 3. When the chuck plate 34 moves in the opening direction, the arm 36a is pushed by the chuck plate 34 and starts to rotate, and when the amount of movement of the chuck plate 34 exceeds, for example, 10 mm set as a threshold, the arm 36a rotates a predetermined angle from the initial position to reach the actuation position. Thereafter, as shown in FIG. 4, the arm 36a slides on the lower surface of the moving chuck plate 34 while its rotation angle is kept constant.

[0025] The main body of the wireless switch 36 is provided with a transmitter that wirelessly transmits an operation identification signal (ON / OFF signal) using power generated by a built-in power generation unit. The power generation unit uses a piezoelectric element or the like that generates electricity using the physical force generated when the arm 36a rotates, eliminating the need for an external power source or battery. The operation identification signal emitted by the transmitter when the switch is operated is received by a receiver built into the control circuit of the construction management device. Then, based on the received operation identification signal, the control unit of the construction management device displays the open / closed state of the chuck plate 34 on the display screen of the display, which serves as a notification unit.

[0026] When the rod rotation drive device 17 configured in this manner is operated to open the chuck, the chuck cylinder 38 of the chuck release mechanism 32 is extended to lower the cone-shaped chuck release member 40 while the rod rotation drive device 17 is stopped. As a result, the body 40a of the cone-shaped chuck release member 40 engages with the inner periphery of both rings 41, and the two chuck plates 34 move in the opening direction as the cone-shaped chuck release member 40 descends. In this way, the engagement between the notches 34a of both chuck plates 34 and the groove 19a of the rod 19 is released, and the rod 19 and the rod rotation drive device 17 are allowed to move relative to each other, for example, the rod 19 can be re-glued, as shown in FIG. 4. At this time, the construction management device displays on the display screen that the chuck is in the open state based on the operation identification signal from the wireless switch 36.

[0027] On the other hand, when the chuck is closed, the chuck cylinder 38 is contracted to raise the cone-shaped chuck release member 40. As a result, the chuck plates 34, 34 move in the closing direction due to the biasing force (elastic force) of the springs 35, 35, and the engagement between the body 40a of the cone-shaped chuck release member 40 and the rings 41, 41 is lost. Here, if the rod rotation drive device 17 is located at a high position, it is often the case that the chuck plate 34 cannot be seen sufficiently. In this case, even if the closing operation is performed, the notches 34a, 34a of the chuck plates 34, 34 do not fit into the groove 19a of the rod 19, and the chuck plate 34 does not close completely.

[0028] In such a half-closed state, the contacts of the wireless switch 36 do not reach the switching position (operation), so the operator knows from the display that the chuck is not completely closed. Therefore, the operator continues to move the rod rotation drive device 17 up and down while searching for the position of the groove 19a of the rod 19 (chuck position). Then, when the positions of both chuck plates 34, 34 and the groove 19a of the rod 19 match, both chuck plates 34, 34 are completely closed, and the notches 34a, 34a engage with the groove 19a of the rod 19, as shown in FIG. 3. At this time, the construction management device displays on the display screen that the chuck is in the closed state based on the operation identification signal from the wireless switch 36.

[0029] In this state, when the rod rotation drive device 17 is operated to rotate the rod 19, the drive shaft 31 and the rod chuck mechanism 23 rotate together, and a pushing propulsion force is applied to the rod 19 by the simple surface pressure between the two chuck plates 34, 34 and the groove portion 19a of the rod 19 as the rod rotation drive device 17 descends.

[0030] In this way, according to the rod rotation drive device 17 of the present invention, since the wireless switch 36 is used as the detection means for detecting the movement of the chuck plate 34, an attachment structure to the rotating part that makes use of the wireless characteristics is achieved. This makes it possible to directly detect the movement of the chuck plate 34, and the chuck state of the rod 19 can be determined reliably. Furthermore, according to the ground improvement machine 11 of the present invention, since it is provided with an alarm unit that notifies the open / closed state of the chuck plate 34 based on a signal from the wireless switch 36, when determining the chuck state of the rod 19, it is possible to receive assistance from the alarm unit in addition to visual confirmation, which contributes to safe and secure work for the operator.

[0031] In particular, the simple configuration consisting of the wireless switch 36 and the associated communication module (receiver) reduces the amount of wiring required for the control circuit, making it easy to connect to an existing construction management system. Therefore, even if the depth measurement needs to be temporarily stopped when the rod 19 is replaced, this temporary stop function can be linked based on accurate operation information from the chuck plate 34, eliminating the need to provide a separate release switch as in Patent Document 2. In other words, there is no need to rely on a configuration that requires the driver to operate the release switch or on software processing to deal with forgetting to release the switch, which contributes to improving the reliability of the construction management system.

[0032] The present invention is not limited to the above-mentioned embodiment, and the rod chuck mechanism may be a mechanism that can chuck the rod at any position using a wedge member that extends in the radial direction of the rod, in addition to the engagement groove structure with the chuck plate. The chuck means may be operated directly by the hydraulic pressure of the chuck cylinder, instead of the elastic force of the spring member. Even in such a mechanism, a wireless switch that detects the amount of movement of the various chuck members can be provided.

[0033] In addition, various types of wireless switches, such as an arm type, a plunger type, a hinge lever type, etc., can be used, and if a self-power generating mechanism as in this embodiment is provided, a power source for operating the transmitter is not required, making assembly and maintenance easier. In addition, the notification unit may be a notification device that notifies visually with an LED indicator light or audibly with a sound or buzzer in addition to a display. [Explanation of symbols]

[0034] 11...ground improvement machine, 12...lower running body, 13...upper rotating body, 14...base machine, 15...leader, 15a...guide pipe, 15b...chain, 16...backstay, 17...rod rotation drive device, 18...guide gib, 19...rod, 19a...groove portion, 19b...square shaft portion, 20...lower guide, 21...operator's cab, 22...equipment room, 23...rod chuck mechanism, 24...drilling head, 24a...drilling blade, 24b...mixing blade, 25...injection hose, 26...swivel joint, 27...anti-rotation rod, 28...mounting member, 29...drive unit body, 30...hydraulic motor for rotary drive, 31...drive shaft, 31a...rod insertion hole, 31b...cylindrical portion, 32...chuck release mechanism, 33...bracket, 33a...rod insertion hole, 33b...mounting seat, 34...chuck plate, 34a...notch, 34b...stay, 35...spring, 36...wireless switch, 36a...arm, 37...slide device, 38...chuck cylinder, 39...spring, 40...cone-shaped chuck release member, 40a...body portion, 41...ring

Claims

1. A rod rotation drive device including a drive device main body rotatably provided with a drive shaft having a rod insertion hole, a rod chuck mechanism provided to be integrally rotatable with the drive shaft, and a chuck release mechanism corresponding to the rod chuck mechanism, The rod chuck mechanism includes a pair of left and right chuck members that engage with an outer peripheral surface of the rod, chuck means that moves both chuck members in the rod radial direction to close the chuck members, and a wireless switch that directly detects the movement of the chuck members and is activated when the amount of movement of the chuck members exceeds a preset threshold value, The rod rotation drive device is characterized in that the wireless switch has a transmitting unit that emits a wireless signal and is attached to the drive shaft so as to be rotatable integrally with the drive shaft.

2. A ground improvement machine equipped with the rod rotation drive device described in claim 1, characterized in that it is equipped with a receiving unit that performs wireless communication with the transmitting unit, and an alarm unit that notifies the open / closed state of the chuck member based on the wireless signal received by the receiving unit.

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