JP2020080753A - Hole digging machine - Google Patents

Abstract

To provide a hole digging machine capable of rotating reversely a screw by a simple method without complicating a device constitution.SOLUTION: A hole digging machine has a handle part 2 having a gripping handle 21, a shaft 4 held rotatably to the handle part 2, a screw 5 arranged on a periphery or a tip part of the shaft 4, and a power supply part 11 for supplying rotation power to the shaft 4. The screw 5 is rotated together with the shaft 4 extending vertically. The shaft 4 has a rotation stop part 9 arranged on the furthermore upper side than the screw 5, and engageable with a tool.SELECTED DRAWING: Figure 1

Description

The present invention relates to a digging machine for digging a hole in the ground or the like.

BACKGROUND ART Conventionally, in tree planting and landscaping, a hole digging machine has been used to form planting holes for planting seedlings or plant seedlings. As a hole digging machine, for example, as described in Patent Document 1, there is a large digging machine attached to the tip of the arm of a hydraulic excavator (see FIG. 5 ). Further, for example, as described in Patent Document 2, there is also a small-sized portable digging machine that includes a small engine that is a power unit and a working unit that has a screw (see FIG. 6 ).

JP, 2003-3778, A JP, 2016-140347, A

In such a hole digging machine, in many cases, due to the power transmission configuration between the power unit and the working unit, the screw is rotated only in one direction by the power unit. On the other hand, when forming a planting hole with a digging machine, for example, in a forest, there is a case where the screw of the working unit is entangled with the root of the plant or the like so that it cannot be removed. In that case, it is necessary to rotate the screw in the reverse direction.

At that time, if the power transmission unit itself or the power transmission configuration between the power transmission unit and the working unit is reversely rotatable, there arises a problem that the cost increases or the configuration becomes complicated and the apparatus becomes large in size. On the other hand, when the screw cannot be reversely rotated, it is necessary to reversely rotate the entire working unit.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide a technique of rotating a screw in a reverse direction by a simple method without complicating the device configuration.

In order to solve the above problems, a first invention of the present application is a digging machine for digging a hole in the ground, comprising a handle portion having a grip handle, and a rotatably held relative to the handle portion. A shaft extending to the shaft, a screw arranged around the shaft and around the tip, rotating with the shaft, and a power supply unit supplying rotational power to the shaft, the shaft being above the screw. And has a detent portion capable of engaging a tool.

A second invention of the present application is the hole digging machine of the first invention, wherein the outer peripheral surface of the rotation stopping portion has a pair of gripping surfaces opposed to each other with the rotation axis of the shaft interposed therebetween.

3rd invention of this application is a hole digger of 2nd invention, Comprising: The outer peripheral surface of the said rotation stop part is a square shape or a hexagonal shape seeing in a rotating shaft direction.

A fourth invention of the present application is the hole digging machine according to any of the first to third inventions, further comprising a cover fixed to the handle portion, the cover being above the screw. A shaft cover portion that surrounds the periphery of the shaft is provided, and a lower end portion of the rotation stopping portion is disposed below a lower end portion of the shaft cover portion.

A fifth invention of the present application is the digging machine of the fourth invention, wherein the cover further has a flange portion that extends from a lower end of the shaft cover portion substantially perpendicular to a rotation axis of the shaft.

6th invention of this application is a hole digger of 4th invention or 5th invention, Comprising: The said shaft cover part has a through hole or the clearance gap provided in a part of circumferential direction, and from the outer side of the said cover. At least a part of the rotation stopping portion is visible through the through hole or the gap.

According to the first invention to the sixth invention of the present application, when the screw is caught on the root of a tree or the like in the ground, it is possible to engage a general tool with the rotation stopping portion and rotate the shaft in the reverse direction. it can. Thus, the screw can be pulled out of the ground by a simple method without rotating the entire working unit having the screw in the reverse direction or changing the device configuration.

In particular, according to the second invention of the present application, the rotation retaining portion can be fixed with the monkey wrench by having the pair of gripping surfaces. This allows the screw to be pulled out of the ground with a simple operation.

In particular, according to the third invention of the present application, it is easy to grip with a monkey wrench, and it is easy to manufacture the rotation stopping portion.

Particularly, according to the fourth invention of the present application, the detent portion can be easily engaged with the tool without being blocked by the shaft cover portion.

In particular, according to the fifth aspect of the present application, it is possible to prevent the hole from becoming too deep due to the flange coming into contact with the ground.

In particular, according to the sixth invention of the present application, the rotation stopping portion can be visually recognized from the upper portion, so that the tool can be easily engaged with the rotation stopping portion even when the screw is stuck in the ground.

It is a perspective view of a hole digging machine. It is a rear view of the working part of a digging machine. It is sectional drawing of the working part of a digging machine. It is a cross-sectional view of a rotation stopping portion. It is an example of a conventional digging machine. It is an example of a conventional digging machine.

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. In the present application, the direction in which the shaft of the digging machine extends is referred to as the “vertical direction”. Further, of the up and down directions, the direction from the base end side of the shaft to the tip end side is referred to as “downward”. Note that the definitions of these directions do not limit the posture of the digging machine when it is used.

<1. First Embodiment>
FIG. 1 is a perspective view of a digging machine 1 according to this embodiment. FIG. 2 is a rear view of the working unit 10 of the digging machine 1. FIG. 3 is a sectional view of the working unit 10 of the digging machine 1.

The digging machine 1 includes a small engine 11, a shoulder belt 12, a power transmission unit 13, and a working unit 10. The small engine 11 is a power supply unit for supplying rotational power to a shaft 4 of the working unit 10 described later. When the small engine 11 is driven, rotational power is output to the power transmission unit 13.

The shoulder belt 12 is a belt for an operator to carry the small engine 11 on his/her back. The operator carries the small engine 11 on the shoulder belt 12 and holds the working unit 10 in his hand to perform a digging work. In this way, by carrying the small engine 11 on the back, the weight of the working unit 10 held in the hand is reduced and the movement of the entire digging machine 1 is facilitated.

The power transmission unit 13 transmits the rotational power output from the small engine 11 to the working unit 10. The power transmission unit 13 of the present embodiment is a power transmission mechanism that includes an outer tube and an inner core shaft and is called a flexible liner or a flexible shaft. In this power transmission unit 13, the inner core shaft rotates inside the tubular outer tube, so that the rotational power input to one end of the inner core shaft is transmitted to the other end. Since the power transmission unit 13 is bendable, the relative positional relationship between the small engine 11 and the working unit 10 can be changed within a predetermined range.

The working unit 10 includes a handle unit 2, a power conversion unit 3, a shaft 4, a screw 5, and a cover 6.

The handle portion 2 is a portion for an operator to grip the working portion 10. The handle portion 2 includes a main body portion 20, a pair of grip handles 21, an operation switch 22, and a drive lever 23.

The main body 20 is a member that extends in the vertical direction. The grip handle 21 is fixed to the upper end of the main body 20. The operator grips the grip handle 21 during the digging work. The operation switch 22 is a switch for switching the shaft 4 between a rotatable state and a stopped state. The operation switch 22 is fixed to the upper end of the main body 20 and is arranged between the pair of grip handles 21.

The drive lever 23 is arranged along one side of the grip handle 21. Therefore, the operator can turn on the drive lever 23 by gripping the drive lever 23 together with the grip handle 21. When the operation switch 22 is set in a rotatable state and the drive lever 23 is turned on, the shaft 4 is rotated by the rotational power transmitted from the small engine 11 via the power transmission unit 13 and the power conversion unit 3.

As shown in FIG. 3, the power conversion unit 3 has a casing 31 and a speed reducer 32 housed inside the casing 31. The casing 31 is a housing fixed to the main body portion 20 of the handle portion 2.

The speed reducer 32 has an input shaft 321 extending in the vertical direction on the upper side, and an output shaft 322 extending in the vertical direction on the lower side. The other end of the inner core shaft of the power transmission unit 13 is connected to the upper end of the input shaft 321. As a result, the rotational power output from the small engine 11 is input to the input shaft 321 via the power transmission unit 13. The speed reducer 32 converts the rotational speed of the rotational power input to the input shaft 321, and outputs the rotational power to the output shaft 322.

The shaft 4 is a cylindrical member that extends vertically. The shaft 4 is held rotatably with respect to the handle portion 2 about a vertically extending rotation shaft. The upper end of the shaft 4 is connected to the output shaft 322 of the speed reducer 32. As a result, the rotational power output from the speed reducer 32 is input to the shaft 4.

The screw 5 is fixed to the shaft 4 and rotates together with the shaft 4. The screw 5 includes a first screw 51 arranged around the shaft 4 and a second screw 52 arranged at the tip of the shaft 4. The first screw 51 and the second screw 52 may be integrally molded or may be separate members.

The cover 6 has a shaft cover portion 61 and a flange portion 62.

The upper end of the shaft cover portion 61 is fixed to the casing 31 of the power conversion unit 3. Further, the shaft cover portion 61 surrounds the periphery of the shaft 4 above the screw 5 with a gap from the shaft 4.

The shaft cover portion 61 has a plurality of through holes 63 and a gap 64 provided in a part in the circumferential direction. By providing the through hole 63 and the gap 64, the weight of the shaft cover portion 61 is reduced.

The flange portion 62 extends from the lower end of the shaft cover portion 61 substantially vertically to the rotation axis of the shaft 4. When the screw 5 forms a planting hole to a sufficient depth during the digging work, the flange portion 62 comes into contact with the ground. As a result, it is possible to prevent the implantation hole from becoming too deep.

In such a digging machine 1, the shaft 4 has a rotation stopping portion 9 which can engage with a tool. The rotation stopping portion 9 is arranged above the screw 5. FIG. 4 is a cross-sectional view of the detent portion 9. As shown in FIG. 4, in the present embodiment, the outer peripheral surface of the rotation stopping portion 9 has a quadrangular shape when viewed in the rotation axis direction of the shaft 4. That is, the outer peripheral surface of the rotation stopping portion 9 has a pair of gripping surfaces 91 that face each other with the rotation axis of the shaft 4 interposed therebetween. As a result, the rotation stopping portion 9 can be gripped and fixed by a general tool T such as a monkey wrench. Therefore, it is possible to reversely rotate the shaft 4 using a general tool T such as a monkey wrench.

In this way, by providing the detent portion 9 capable of engaging with the tool, when the screw 5 is caught on the root of a tree or the like in the ground, the shaft 4 can be reversely rotated using the tool. Therefore, the screw 5 can be reversely rotated by a simple method without reversely rotating the entire working unit 10 or changing the device configuration.

In addition, in the present embodiment, the rotation stopping portion 9 has a quadrangular outer peripheral surface when viewed in the rotation axis direction, but the present invention is not limited to this. For example, the rotation stopping portion may have a hexagonal outer peripheral surface when viewed in the rotation axis direction. Even in this case, since the shaft has the pair of gripping surfaces facing each other with the rotation axis of the shaft interposed therebetween, the shaft can be gripped and fixed by a tool such as a monkey wrench. When the outer peripheral surface of the rotation stopping portion has a quadrangular shape or a hexagonal shape when viewed in the rotation axis direction, it is easy to grip with a tool such as a monkey wrench and the rotation stopping portion is easy to manufacture.

In addition, the detent portion does not necessarily have a gripping surface as long as it is configured to prevent the engaged tool from slipping in the circumferential direction. For example, it may be a protrusion that protrudes from a part of the outer peripheral surface of the circular shaft 4 when viewed in the rotation axis direction in the circumferential direction. In that case, when the outer peripheral surface of the shaft 4 is gripped by a tool such as a monkey wrench, even if the tool slips in the circumferential direction, it hits the protruding portion and is locked in the circumferential direction. This allows the shaft 4 and the screw 5 to be pulled out of the ground using a tool such as a monkey wrench.

In this digging machine 1, the lower end portion of the rotation stop portion 9 is arranged below the lower end portion of the shaft cover portion 61. As a result, at least a part of the detent portion 9 is exposed from the cover 6 below the cover 6. As a result, the tool can be easily engaged with the rotation stopping portion 9 without being blocked by the cover 6.

Further, in this digging machine 1, the shaft cover portion 61 has a plurality of through holes 63 and a gap 64 provided in a part in the circumferential direction. Thereby, at least a part of the rotation stopping portion 9 can be visually recognized from the outside of the cover 6 through the through hole 63 or the gap 64. Therefore, it is easy to visually recognize the rotation stopping portion 9 and its periphery from above the rotation stopping portion 9. Thereby, even when the screw 5 is stuck on the ground, the tool can be easily engaged with the rotation stopping portion 9.

<2. Modification>
Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment.

In the digging machine of the above-described embodiment, the small engine that is the power supply unit is movable relative to the working unit, but the present invention is not limited to this. The power supply unit and the working unit may be integrally configured.

Further, in the digging machine of the above embodiment, the power supply unit is the engine, but the present invention is not limited to this. The power supply unit may have another configuration such as a motor as long as it can supply rotational power.

Further, in the above-mentioned hole digging machine, the outer surface of the rotation stopping portion serving as the engagement surface with the tool is arranged outside the outer surface of the shaft, but the present invention is not limited to this. The engagement surface with the tool may be formed by flattening a part of the outer surface of the shaft.

Further, the detailed configuration of the digging machine may be different from the shapes shown in the drawings of the present application. Further, the respective elements appearing in the above-described embodiments and modifications may be appropriately combined within a range where no contradiction occurs.

DESCRIPTION OF SYMBOLS 1 Digger 2 Handle part 3 Power conversion part 4 Shaft 5 Screw 6 Cover 9 Rotating part 10 Working part 11 Small engine 13 Power transmission part 21 Grip handle 32 Reduction gear 51 1st screw 52 2nd screw 61 Shaft cover part 62 Flange 63 Through hole 64 Gap 91 Gripping surface

Claims (6)

A digging machine for digging a hole in the ground,
A handle portion having a grip handle,
A shaft that is rotatably held with respect to the handle portion and that extends vertically;
A screw that is arranged around the shaft and at the tip, and rotates together with the shaft,
A power supply unit for supplying rotational power to the shaft,
Have
The shaft is
A hole digging machine, which is arranged above the screw and has a rotation stopping portion capable of engaging a tool. The digging machine according to claim 1,
The outer peripheral surface of the rotation stopping portion is
A digging machine having a pair of gripping surfaces facing each other with the rotation axis of the shaft interposed therebetween. The digging machine according to claim 2,
The hole digging machine has an outer peripheral surface having a quadrangular shape or a hexagonal shape when viewed in the rotation axis direction. The digging machine according to any one of claims 1 to 3,
Further comprising a cover fixed to the handle portion,
The cover is
On the upper side of the screw, has a shaft cover portion that surrounds the periphery of the shaft,
The hole digging machine, wherein a lower end portion of the rotation stopping portion is disposed below a lower end portion of the shaft cover portion. The digging machine according to claim 4,
The cover is
A digging machine further comprising a flange portion extending from a lower end of the shaft cover portion substantially perpendicular to a rotation axis of the shaft. The hole digging machine according to claim 4 or 5,
The shaft cover portion is
Has a through hole or a gap provided in part in the circumferential direction,
A digging machine capable of visually recognizing at least a part of the detent portion from the outside of the cover through the through hole or the gap.

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