JPH0572518B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a digging tooth that is used by being attached to the tip of a casing for an earth auger.

Conventional Technology All earth auger casings are currently limited to a wall thickness of 50 mm or less in order to reduce digging resistance. For this reason, generally, the thickness between the upper and lower surfaces is approximately equal to the wall thickness of the casing, and the overall rectangular integral shape is used as the drilling tooth for the casing. It is inserted into the notches formed at equal intervals on the tip of the casing, and is attached to the tip of the casing by welding the three sides to the casing from both the front and back sides.

Problems to be Solved by the Invention With this configuration, if the excavating tooth wears beyond its usable limit, the welded part must be cut, the excavating tooth must be warped, and the tooth must be replaced, which requires considerable effort. It is very clear that this requires skill and skill. In order to solve this problem, attempts have been made to adopt a two-piece excavation tooth consisting of an adapter element and a tooth tip element in the earth auger casing, but since the adapter element has a mounting part and a long nose part, When the adapter element is fixed by welding to the notch of the casing through its attachment portion, the nose portion largely protrudes from the tip of the casing. Since the tooth tip element fits and is held in this protruding long nose section, the distance from the cutting tip of the tooth tip element to the tip of the casing becomes unduly long, which results in a large digging resistance on the digging tooth. However, the strength of the attachment of the adapter element to the casing cannot withstand the force of this excavation resistance, resulting in the disadvantage that the attachment portion may eventually be damaged.

The object of the present invention is to provide a two-piece excavating tooth that solves these problems.

Means for Solving the Problems In order to achieve this object, the present invention provides an adapter body which is adapted to be fixed by engaging with a notch formed at the tip of an earth auger casing; an adapter element including a nose portion formed integrally with the adapter body at the center of the upper part and having a tip portion extending forward beyond the adapter body; and an adapter element including a notch recess formed in the lower surface of the adapter body; To provide an excavating tooth for an earth auger casing, characterized in that it consists of a tooth tip element having a socket extending forward from the rear end and a tongue-shaped part inserted into the notch recess so as to fit together.

Embodiment FIG. 1 shows the tip of a casing 2 for an earth auger, and FIG.
This schematically shows the state in which the drilling tooth 1
As shown in Figs. 2 and 3, the earth auger casing 2 is now fixed to notches 3 (see Fig. 1) formed at equal intervals in the circumferential direction at the tip of the earth auger casing 2. It consists of an adapter element 4 and a tooth tip element 5. As shown in FIGS. 4 to 6, the adapter element 4 has a shape to be inserted into the notch 3 of the casing 2, specifically an adapter body 6 having a substantially rectangular shape when viewed from above. 6 has a rear end surface 10 with two parallel sides 7, 7 and two grooves 8, 9 adapted to engage in the cutout 3 of the casing 2. The adapter body 6 is integrally formed with a nose portion 11 at the center of its upper portion, and step portions are formed on both sides of the nose portion 11. The nose portion 11 has a tip portion 12 extending forward beyond the adapter body 6, and has forwardly tapered side surfaces 13, 13 and an upper surface 11' which serve as pressure receiving surfaces. The adapter body 6 also has a cutout recess 14 on its lower surface that is open at the front and has side surfaces 15, 15 that widen toward the front.

As shown in FIGS. 7 to 9, the tooth tip element 5
is provided with a socket 16 extending forward from the rear end and fitting into the nose portion 11 of the adapter body 6, and the socket 16 is connected to the pressure receiving surface 13 of the nose portion 11,
rearwardly flared opposed side surfaces 17, 17 serving as pressure receiving surfaces cooperating with 13 and nose portion 11;
It has an upper inner surface 16' cooperating with the upper surface 11'. The sides of the tip element forming part of the socket 16 are formed as side flanges and are adapted to rest on the step of the adapter body 6 when the tip element is attached to the adapter element. A tongue 18 extends rearwardly on the underside of the tip element 5 and is adapted to engage in the cutout recess 14 of the adapter body 6 . The side surfaces 19, 19 of the tongue-shaped portion 18 are tapered rearward in order to cooperate with the side surfaces 15, 15 of the cutout recess 14.

The adapter element 4 is inserted into the cutout 3 of the casing 2.
side 7 of the adapter body by plugging it into
and the rear end face 10 engages the inner side of the cutout, and the adapter element 4 is welded to the casing 2 from the inside of the casing and from the outside and the inside via the grooves 8, 9. The tooth tip element 5 is thus attached to the casing 2
In this case, the socket 16 of the tooth tip element 5 and the adapter element 4 are inserted into the adapter element 4 fixed to the
The side flange of the tip element 5 is positioned at the stepped portion of the adapter body, and the tongue portion 18 of the tip element 4 is inserted into the notch recess 14 of the adapter body 6 ( (See Figures 10 and 11). The engagement between the notch recess 14 and the tongue 18 is effective for strengthening the connection force of the tip element 5 with the adapter element 4. A wedge insertion hole 2 is provided in the adapter element 4 and the tooth tip element 5.
0 and 21, respectively, and the hole 20 is sized and shaped to fit with the wedge element 22,
Hole 21 is sized and shaped somewhat larger than wedge element 22. Connect the tooth tip element 5 to the adapter element 4
The wedge element 22 is inserted into the hole 20,2
1 from the inside of the casing 2, the wedge element 22 is fitted and fixed in the hole 20 of the adapter element, and the tooth tip element 5 is attached to the adapter while being able to move back and forth somewhat with respect to the adapter element 4 by the wedge element 22. Connected to element 4.

During drilling, the tooth tip element 5 is provided with the
As shown in Figure 1, loads are applied in the directions of arrows A, A', and C. These loads are mainly transmitted to the adapter element 4 through the nose part, and the loads in the direction of arrow B are transmitted to the side surface 17 of the socket 16 of the tooth tip element 5.
and the side surface 13 of the nose part 11 of the adapter body and the side surface 19 of the tongue 18 of the tip element 5
is transmitted from the tip element 5 to the adapter element 4 due to the cooperative action of the side surface 15 of the notch recess 14 of the adapter body. The upper surface 11' of the adapter body 4, that is, the upper surface 11' of the nose portion 11 and the upper surface 16' of the socket 16 of the tooth tip element 5 are formed horizontally in the example shown in the figure. It may be tilted forward and downward to make insertion easier. In this case, the inclination angle is 5
It is desirable that the temperature is below 30 degrees. This means that the pressure receiving surface 1 of the nose portion 11 and the socket 16 is
This is because the area of 3.17 is reduced. Therefore, from the viewpoint of making the pressure receiving surface as large as possible,
The angle of inclination should not exceed 5 degrees.

Effects of the Invention According to the present invention, the tooth tip element can be inserted into the adapter element fixed to the notch formed at the tip of the casing so as to substantially surround the adapter element. The distance from the cutting edge to the attachment point between the adapter element and the casing becomes very short, so the digging resistance force is reduced accordingly, and the attachment point between the adapter element and the casing can sufficiently withstand the digging resistance. In addition, since the adapter element is covered with the tooth tip element due to the fit between the nose part and the socket, it is not exposed to the outside of the casing, so damage or wear of the adapter element can be completely prevented and its service life can be extended. It stretches significantly. Furthermore, by inserting the tongue-shaped portion of the tip element into the notch recess of the adapter body, the connection of the tip element to the adapter element becomes more secure.

[Brief explanation of drawings]

Fig. 1 is a perspective view of the tip of the earth auger casing, Fig. 2 is a partial side view of the earth auger casing with excavation teeth according to the present invention attached, and Fig. 3 shows how the adapter is attached to the casing. 4 is a perspective view of the adapter element; FIG. 5 is a side view of the adapter element; FIG. 6 is a bottom view of the adapter element; FIG. 7 is a perspective view of the tip element;
Fig. 8 is a side view of the tooth tip element, Fig. 9 is a bottom view of the tooth tip element, and Fig. 10 is a side view of the excavating tooth according to the present invention in which the adapter element and the tooth tip element are fitted and connected by a wedge element. , FIG. 11 is a bottom view thereof. 2... Casing, 3... Notch, 4... Adapter element, 5... Tooth tip element, 6... Adapter body, 11... Nose part, 12... Tip part,
14... Notch recess, 16... Socket, 18... Tongue-shaped part.

Claims (1)

[Claims] 1. An adapter body that is fixed by engaging with a notch formed at the tip of the earth auger casing, and an adapter body that is formed integrally with the adapter body at the center of the upper part and extends forward beyond the adapter body. an adapter element including a nose portion having an elongated tip; and a cutout recess having a flared side face and an open front on a lower surface of the adapter body;
An excavating tooth for an earth auger casing, comprising a tooth tip element having a socket extending forward from the rear end and a tongue-like part inserted into the notch recess.