JPS5848718B2 - Earth auger expansion device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an earth auger enlarging device that allows a movable cutting edge at the tip of a screw in a perforation using an auger screw to be freely enlarged from the ground, and that can detect the amount of the enlargement.

Recently, in earth augers that use cutting blades attached to the tip of the screw shaft to drill into the earth, the diameter of the root of the hole has been enlarged to increase the supporting load of the hole that is driven into the hole. A method of injecting hardening fluids such as cement milk began to be used.

However, in the past, in order to enlarge the base of the drilled hole, a movable cutting blade was attached to the lower end of the screw shaft, and when the screw shaft was strongly pushed down, the movable cutting blade was pushed and expanded against the force of the return spring. Alternatively, there were devices that pushed the movable cutting blade apart by reversing the screw shaft, but in any case, the amount of expansion of the movable cutting blade could not be adjusted arbitrarily and accurately, or there was no indication device to detect the amount of expansion from the ground. If it is difficult to attach the movable cutting blade, or if the return operation of the enlarged movable cutting blade is uncertain, or even if an indicating device can be attached, it may be necessary to add a screw shaft or rod for the enlargement or indicating device as appropriate. Since the holes are drilled deeply, there are a number of drawbacks, mainly that the structure of this joint part is unreliable in terms of operation, strength, and accuracy.

The present invention expands the diameter of the row of movable cutting blade tips by vertically moving the cutting blade operating ring attached to the lower end of the feed screw rod concentrically near the bottom of the screw shaft and by a link mechanism.
At the same time, an expanding rod is connected to the top of the feed screw and protrudes to the top of the main body of the drilling machine, and the rotation of the expanding rod is stopped by a rod fixing device such as a hydraulic cylinder fixed to the main body. by rotating the movable cutting blade relative to the screw shaft, the movable cutting blade is moved up and down with respect to the screw shaft to expand or reduce the outer diameter of the movable cutting blade, and the expanding rod and the screw shaft are The amount of expansion of the movable cutting blade can be accurately detected on the ground by detecting the relative axial displacement between them using an expansion amount detection mechanism provided on the main body and detecting the outer diameter of the tip of the movable cutting blade. Returning can be ensured by reversing the screw shaft and locking the expansion rod, and screw shafts and expansion rods can be added using prismatic socket joints or key connections, making operation easy. The purpose is to provide a highly reliable earth auger expansion device.

The conventional earth auger enlarging device and the present invention will be described below with reference to the drawings. Since the same reference numerals in each drawing indicate the same parts or the same two parts with the same name, the explanation of the following parts will be omitted.

Figure 1 is a partial front view showing an example of the lower part of the screw shaft of a conventional drilling machine. Shafts 3-1.3-2 are located near the bottom of the screw shaft 1 on which the screw 2 that carries sand to the ground is wound, on the front and opposite sides of the figure, and movable cutting blades 4-1.4-2 are located around the shafts, respectively. 2 is rotatably fitted and biased by a spring (not shown) so that the diameter of the tip of the movable cutting blade is minimized.

If you press down the screw shaft 1 with a strong force in the axial direction while drilling a hole while rotating it clockwise when looking at the screw shaft 1 from above, the tips of the movable cutting blades 4 and 4-2 will be pushed and the arrows shown in the figure As shown by the two-dot chain line, the hole can be enlarged to the left and right to form a large diameter hole.

Further, when the downward force of the screw shaft 1 is weakened, the movable cutting blade is returned by the spring and the diameter of the tip of the movable cutting blade is reduced.

However, in this example, the amount of expansion of the tip of the movable cutting blade is affected not only by the downward force of the screw shaft but also by the condition of the earth and sand during excavation.Since it is a dog, it cannot be determined, and there is also a detection device that can detect the amount of expansion on the ground. There are disadvantages such as difficulty in installing the

The hollow hole 1a shown by the dotted line in the screw shaft 1 and the hole 1b at its bottom are used to feed fluids such as water and air so that the excavated earth and sand can be easily transported to the ground by the screw 2, and are used to feed the holes after drilling. This is for injecting a hardening agent such as cement milk into the bottom of the container.

FIG. 2 is a plan view of the lower part of the screw shaft of another conventional embodiment taken in a direction perpendicular to the axis, and the screw 2 is not shown because it would be complicated.

In this example, the shaft 6-1- is attached to the brackets 5-1 and 5-2 protruding near the bottom of the screw shaft 1.
6-2, movable cutting blades γ-1 and γ-2 are rotatably fitted.

Therefore, when the screw shaft 1 is rotated to the left in the figure, the diameter of the tip of the movable cutting blade is enlarged due to excavation resistance, as shown by the arrow and the two-dot chain line in the figure, and when the screw shaft 1 is rotated to the right, the movable cutting blade becomes movable. The diameter of the tip of the cutting blade is reduced due to excavation resistance, as shown by the solid line.

However, this embodiment also has drawbacks such as the amount of expansion of the tip of the movable cutting blade cannot be determined because it is affected by the condition of the earth and sand during excavation, and it is difficult to install a detection device that can detect the amount of expansion on the ground. be.

FIG. 3 is an explanatory axial cross-sectional view of the earth auger dog expansion device according to the first embodiment of the present invention, in which two to several brackets 23 are attached near the bottom of the bottom screw shaft 21 around which the screw 22 is wound. 1 and 23-2 are projected, and the movable cutting blades 25-1.2 and 5-2 are rotatably lowered onto shafts 24-, 24-2 attached to the tips of the brackets.

On the other hand, the lower feed rod 26a and the upper feed rod 26b are extended to the feed screw 26 which is screwed into the female feed screw 21a provided in the axial direction of the lower inner hole of the screw shaft, and a hollow hole 26C is formed in the axial center. It passes through the top and bottom.

A thrust bearing 2 is attached to the lower end of the lower feed rod 26a.
A cutting blade operating ring 28 is rotatably fitted with its axial position held down via the movable cutting blades 25, 25-2.
1, 29-2 protrudes and is pin-connected to the movable cutting blade 25-1, 25-2 via a link 30-1, 30-2.

Note that an appropriate number of fixed cutting blades 35-1 and 35-2 are attached to the bottom of the cutting blade operating ring as necessary.

On the other hand, above the bottom screw shaft 21 is an intermediate screw shaft (not shown) with a screw wound around its outer periphery via a hexagonal socket joint 33 for the purpose of transmitting rotational force and a retaining pin 34 driven in diagonally to the hexagonal socket joint 33. There are no holes, but they can be added as needed depending on the depth of the hole.

) or a top screw shaft 31 having a screw 32 wound around its outer periphery is connected.

On the other hand, there is a hollow hole 31a in the axial center of the top screw shaft 31, into which a top expansion rod 36 is inserted and connected to the top feed rod 26b via a key 3γ for the purpose of rotation transmission. connected.

Additionally, a hollow hole 36a is also provided at the axial center of the upper feed rod 26b.
A packing 38 is provided in order to connect to the hollow hole 26C and to fluidly interrupt the force section.

(Although not shown, intermediate enlarging rods are added as appropriate depending on the depth of the hole to be drilled.)

) Next, the upper part of the top screw shaft 31 is the gear 31b.
is integrally mounted and rotatably supported by the main body 40 of the earth auger located below the case via the tapered roller bearing 39 and the thrust bearing 41, and further mounted on the main body 40 is an electric motor 42-1, 42-2 with a reduction gear. A pinion 43-1, which is attached to the shaft of and meshes with the gear 31b,
43-2.

On the other hand, the top dog expansion rod 36 is integrally provided with a ratchet wheel 44 with a groove 44a cut on the outer periphery on the part that protrudes from the top of the main body 40, extends further upward, and has a swivel joint 45 at the top end. Hollow hole 36a. It is used for purposes such as sending air, water, cement milk, etc. to the bottom of the borehole through 26c to make it easier to transport excavated earth and sand to the ground using screws 22 and 32, and injecting hardening material at the bottom of the borehole.

On the other hand, the upper bracket 46-1.46-2 of the main body 40 has a hydraulic cylinder 4 having a rond 4B-1.48-2.
γ-1, 4γ-2 are their rondo 4 8-1. 4
When 8-2 is pushed out, it is installed in a position where it engages with the groove 44a of the ratchet wheel 44.

In addition, a thrust bearing 49 is mounted on the upper part of the stopper wheel 44.
The detection wheel 50 is placed on the bracket 46 via the feather key 51, and is engaged with the bracket 46 via the feather key 51.
6 is equipped with a main body of a potentiometer 52 with a built-in fixed resistor 53, and the detection wheel 50 is equipped with a potentiometer 52.
A sliding piece 54 is attached.

With the above configuration, when the main body 40 of the earth auger is lowered while being guided by the tower guide, and at the same time the electric motors 42-1 and 42-2 with reduction gears are rotated, the pinions 43-1 and 43-2 are rotated. Rotation is transmitted to the gear 31b1 top screw shaft 31 and bottom screw shaft 21, and the fixed cutting blade 35-1.35-2 and the movable cutting blade 25-
1,25-2 rotates and begins drilling into the ground.

At this time, the movable cutting blades 25-1, 25-2 and the cutting blade actuator are in the position shown in FIG.

Also, the rods 4B- of the fluid pressure cylinders 4γ-1, 4l-2
1.48-2 is in the retracted state, so the top expansion rod 36 and the bottom feed rod 26a rotate together with the screw shaft on the circumference due to friction, so the movable cutting blades 25-1 and 25-2 Drilling progresses while maintaining the position shown.

Needless to say, as the drilling progresses, intermediate screws, shafts, and intermediate expansion ronds will be added.

Next, when the predetermined depth of expansion is reached, the hydraulic cylinder 4γ-1
, 4γ1 to push out the rods 48-t, 48-2, they engage with the grooves 44a and the pawl 44 stops, so the top expansion rod 36 and the top feeding rod 26b stop and the bottom screw Relative rotation occurs between the shaft 21 and the feed screw 26, the lower feed rod 26a, and the cutting blade operating ring 28, which move upward, so that the link 30-1.30-
2, the movable cutting blades 25-1, 25-2 move around the shaft 24,
．． Since it rotates outward around 24-2 and the tip expands, the bottom of the hole can be enlarged.

This expansion amount is transmitted to the top expansion rod 36, the detection wheel 50, and the sliding piece 54 as a relative upward movement amount of the lower feed rod with respect to the bottom screw shaft 21, so the potentiometer 52 outputs the amount of movement. By doing so, the amount of expansion of the tip of the movable cutting blade 25-1, 25-2 can be detected on the ground.

Since the top expansion rod 36 has weight, there is no risk of axial play occurring between it and the top feed rod, and since the rotation is reliably transmitted by the key 37, the amount of expansion can be detected with high precision. It is easy to add intermediate expansion ronds and is highly reliable.

Therefore, in combination with the drilling feed rate, the movable cutting blade 2 5-1.2
By accurately enlarging 5-2, the shape of the hole enlargement can be drilled in a predictable manner.

FIG. 4 is a partial axial cross-sectional view showing another embodiment of the device for detecting the amount of expansion at the tip of the movable cutting blade. In the embodiment shown in FIG. 3, the amount of expansion is detected using the top screw of the top expansion rod 36. The detection was performed based on the amount of displacement in the axial direction with respect to the shaft 31, but in the embodiment shown in FIG. The difference is that

That is, the indicating device 6 attached to the main body 40 connects the shaft 65a of the gear 65 that further meshes with the pinion 43-1 that meshes with the gear 3lb fixed to the upper part of the top screw shaft 31.
The main body 4 is connected to one shaft 61a of the main body 4, is integrally fixed to the top enlargement rod 36, and has a thickness greater than the stroke of the top enlargement rod.
The shaft 6 of the gear 68 is rotatably supported by the bracket 6γ mounted on the bracket 46-1.
By connecting 8a to the other shaft 62a of the indicating device 60 with a flexible shaft 69, the top dog expansion rod 3
6 and the top screw shaft 31, the pointer 63 is moved and the amount of expansion of the movable cutting edge is detected on the indicator plate 64.

An example of the internal mechanism of the indicating device 60 is shown in FIG.

In other words, it is an application of a differential gear mechanism, and the bevel gears 6 have the same number of teeth.
1.62 are rotatably supported by the bottom cover γ1 and the case γ0 facing each other, and the respective shafts 61a and 62a are made to protrude into the case example, and are meshed with both opposing bevel gears 61 and 62.
More than one planetary bevel gear γ2-1, γ2-2 is rotatably supported by a planetary shaft T3, and the planetary shaft γ3 is connected to both bevel gears 61,
? It is rotatably supported in the center recess of No. 2, and the end of the row is engaged with the carrier T4.

The carrier γ4 is rotatably supported by both shafts 61 a and 62a, and is axially supported by the bottom cover γ1 and the case TO.

Further, the carrier axis γ4a surrounds the axis 62a and the case TO
A pointer 63 is fixed so as to protrude from the row.

Further, the indicator plate 64 is fixed to the case 10. As mentioned above, the shafts 61a and 62a are the shafts 6 of the gear 65, respectively.
5a and the shaft 68a of the gear 68 via a flexible shaft 69, and the case γ0 and the bottom cover γ1 are connected to the main body 4.
Fixed to 0.

With the above structure, if the ratio of the number of teeth between the gear 68 and the gear 66 and the number of teeth between the gear 65 and the gear 3lb are made equal, the top screw shaft and the top canine expansion rond can rotate in the same direction and in the same way. If the feed screw 26 is not sliding, the pinion 43-1 is inserted between the gears 65 and 31b, so the bevel gears 61 and 62 are opposite to each other at the same rotation speed. Rotate in the direction.

Therefore, although the planetary bevel gears 72-1 and 72 rotate, the planetary shaft γ3 and the carrier T4 do not move.

Therefore, the pointer 63 does not move. Next, the fluid pressure cylinder 4T,
When 47-2 is activated and the top expansion rod is fixed, a relative rotational displacement occurs between it and the top screw shaft, so carrier γ4 rotates and the pointer moves, increasing the amount of expansion of the movable cutting blade. can be detected on the ground.

In this example, the final detection part is based on the visual sense using the support plate 64 and the pointer 63, but it is clear that electrical detection can also be achieved by replacing it with a rotary potentiometer.

In addition, the xylem screw shaft 31 and the top dog expansion rod 3
In order to detect the relative rotational displacement with respect to 6, in addition to using the above-mentioned differential gear mechanism, an electric rotation detection device (known in the art) is attached to each of the top screw shaft g and the top dog expansion rod. It is clear that detection can also be made by electrically comparing the values (using known devices).

As described above, the present invention utilizes the vertical movement of the cutting blade operating element which is rotatably supported by the bottom screw of the drilling machine and the lower feed rond of the feed screw provided in the axial direction of the axis of the shaft, through the link mechanism. In addition to expanding and contracting the tip of the movable cutting blade, a large part of the expanding rond connected to the upper feed rond of the feed screw is made to protrude above the ground and is appropriately stopped by a stop mechanism, thereby increasing the distance between the tip and the bottom screw shaft. By applying a relative rotational displacement to operate the feed screw and at the same time detecting this relative rotational displacement or the relative axial displacement due to the feed and screw, the amount of expansion of the movable cutting blade is detected on the ground and the amount of expansion is detected. It is possible to provide an earth auger expansion device that can accurately perform fftlJfl, easily add intermediate screw shafts and intermediate expansion rods, and has high reliability in terms of operation, strength, and accuracy.

[Brief explanation of drawings]

FIG. 1 is a partial front view showing an example of the lower part of the screw shaft of a conventional earth auger. FIG. 2 is a plan view of the lower part of the screw shaft of another embodiment of the conventional earth auger, cut in the direction perpendicular to the axis. FIG. 3 is an explanatory axial cross-sectional view of the first embodiment of the present invention. FIG. 4 is a partial axial cross-sectional view of an enlargement amount detection device according to a second embodiment of the present invention. FIG. 5 is an axial cross-sectional view of the indicating device. 1... Screw shaft, 4 -1 * 4
-2 *γ-1.7,,25-1.25 -2...
...Movable cutting blade, 21...Bottom screw shaft, 26...Feed screw, 28...
Cutting blade operating ring, 30-1, 30-2... link,
31...Top screw shaft, 3lb...
...Gear, 33...Hex socket joint, 3
4...Keeping pin, 36...Top dog expansion rod, 3γ...Key, 40...
Main body, 42-1, 42-2...Electric motor with reducer, 43-1.43-2...Pinion, 44...
...Pawl, 44a...Groove, 45...
...Swivel joint, 4γ-1, 4γ-2...
...Fluid pressure cylinder, 50...Detection wheel, 52
...... Potentiometer, 60... Indicating device, 63... Pointer, 64... Indicating board,
γ4...Carrier.

Claims (1)

[Claims] 1. In an earth auger device using an auger screw, the bottom screw shaft with the screw wrapped around the circumference of the row has a movable cutting blade supported rotatably in the A direction by a hinge at the bottom of the bottom screw shaft. is connected to the lower part of the intermediate screw shaft or the top screw shaft, through which the expansion rod passes through the center, and the prismatic socket 11 through a rotation transmission joint such as a pin, etc., and the top screw shaft is rotatable by a bearing inside the main body case. a cutting blade rotation transmission mechanism supported by a motor and driven by a prime mover, and a cutting blade supported freely only in the rotational direction by a lower feed rond of a feed screw provided in the axial direction of the axial center of the bottom screw shaft. An operating ring is provided, and the cutting blade operating element is connected to the movable cutting blade by a link, and the upper part of the upper feed iron of the feed screw and the lower part of the expanding iron are connected by a rotation transmission joint such as a key or a prismatic socket fJ. Furthermore, a hydraulic opening cylinder 15 engages and disengages from a pawl fixed to the enlargement rod protruding from the main body case, and an enlargement mechanism for the movable cutting blade is formed by any brake mechanism, and furthermore, the expansion mechanism for the movable cutting edge is formed by a potentiometer or the like. 1. A device for enlarging an earth orca, comprising: a detection mechanism that detects axial displacement between an enlarging iron and the main body case to determine the amount of expansion of the movable cutting blade. 2. In an earth auger device using an auger screw, the bottom screw shaft with a screw wrapped around its outer periphery has a movable cutting blade supported rotatably in rows by a hinge at the bottom, and an enlargement rond at the top. The intermediate screw shaft or the lower part of the top screw shaft passing through the shaft is connected with a rotation transmission joint such as a prismatic socket and a retainer such as a pin, and the top screw shaft is rotatably supported by a bearing in the main body case and driven by a prime mover. A cutting blade rotation transmission mechanism comprising: a cutting blade rotation transmission mechanism; and a cutting blade operating ring which is freely supported only in the rotational direction on a lower feed rond of a feed screw provided in the axial direction of the axial center of the bottom screw shaft; The operating ring is connected to the movable cutting edge by a link, and the upper part of the upper feed rond of the feed screw and the lower part of the expansion rond are connected by a rotation transmission joint such as a key or a prismatic socket 7a', and furthermore, the operating ring is connected to the movable cutting edge by a link, and the upper part of the upper feed rond of the feed screw and the lower part of the expansion rond are connected by a rotation transmission joint such as a key or a prismatic socket 7a'. an enlarging mechanism for the movable cutting blade consisting of a brake mechanism such as a pawl fixed to the enlarging rod protruding from the movable cutting edge and a hydraulic lock cylinder that disengages the latch; furthermore, rotation of the enlarging rod and the top screw shaft The rotation of the differential gear is indirectly guided to both shafts of the differential gear by gears, etc., and the movement of the carrier of the differential gear is taken out to a pointer or a potentiometer, thereby controlling the relative relationship between the expansion rond and the top screw shaft. 1. A device for expanding an earth auger, comprising: a detection mechanism that detects rotational displacement of a target and determines an amount of expansion of the movable cutting blade.