JPH0667592U - Ground excavator orientation correction head - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a direction correcting head which is less meandering and which can be effectively applied to excavation of various types of ground without impairing the cost advantage. [Structure] A tip portion 12 of a head 10 is formed in a pyramidal shape, and a tip portion 11 is arranged on the axis of a mounting portion 14. Moreover, by providing a plurality of grooves 20 on the circumferential side of the tip portion 12,
The tip 12 has an uneven surface area.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention is a direction correction head that is located at the head of a ground excavator and regulates a traveling direction by excavation, and particularly relates to a technology that can be effectively used for ground excavation by a non-excavation method.

[0002]

[Prior art and its problems]

 Conventionally, when performing plumbing work for water, gas, etc., for example, a starting shaft and a reaching shaft are dug at specific locations on a road, a ground excavator is installed in the starting shaft, and the ground is excavated from the side wall of the starting shaft. The ground excavation will be carried out using a non-excavation method, in which a tunnel pipeline for piping from the starting shaft to the reaching shaft is formed. Such an excavation method has an advantage that the space occupied by roads and the like is small at the time of construction, but it has a drawback that the traveling direction of the excavation must be corrected in a timely manner because the excavation is in a blind state.

Therefore, the ground excavator used for this purpose is usually provided with some direction correcting means. The conventional direction correcting means (a) is a type that changes the direction of the direction correction head located at the head of the ground excavator with respect to the axis of the shaft on the excavator side independently of the shaft (for example, the actual open shovel). No. 62-133787), and (b) a direction correcting head that integrally changes the direction with the shaft portion on the excavator side (see, for example, Japanese Utility Model Laid-Open No. 3-62187). You can When the two types are compared, the former type is easy to correct the direction because the head itself changes direction independently, while the latter type is easy to correct the direction, while the latter type has the head integrated with the shaft. The fix is a little difficult. However, the former type requires a mechanism for correcting the direction between the head and the shaft portion, so that the structure is complicated and the cost is disadvantageous. In that respect, the latter one has a simple structure and is advantageous in terms of cost.

The inventor of this application focused on the latter type of direction correcting head and tried to improve it. As shown in FIG. 4, the conventional head 30 of this type has a tip portion 32 formed by obliquely cutting a cylinder, which causes some problems due to the characteristics of the shape. The first problem is that a biased force (ground reaction force) is constantly applied to the head 30, and therefore an unreasonable force is applied not only to the head but also to the body of the excavator. The second problem is that when the head 30 rotates, the tip moves between X and Y, and there is a high possibility of meandering. This problem is especially noticeable in impact type excavators. Further, the third problem is that when the head 30 is strongly pressed against the ground, the head 30 bends greatly, so that the insertion force or the penetration force is limited, so that the applicable ground is narrow.

[0005]

[The purpose of the device]

 The present invention has been made in consideration of the above points, and is a technology that can be effectively applied to excavation of various types of ground without sacrificing the cost advantage, with less meandering. The purpose is to provide.

[0006]

[Means and actions therefor]

 The direction correcting head of this invention has a conical shape at the tip end facing the ground, and has the following structural features. A. The center of the tip with the smallest diameter is located on the axis of the attachment part for attachment to the excavator side. B. A plurality of grooves along the axial direction are provided on the peripheral side portion of the conical shape. C. When the tip portion is bisected by the plane including the axis, the surface area on one side of the bisector is larger than that on the other side. Due to these characteristics, various grounds can be effectively excavated while having an effective direction correction function and less meandering.

[0007]

【Example】

 FIG. 1 is a side view of a direction correcting head 10 according to a first embodiment of the present invention, and FIG. 2 is a sectional view taken along line 2-2 of FIG. The direction correcting head 10 integrally includes a substantially conical tip portion 12 and a mounting portion 14 continuing from the tip portion 12. The tip portion 12 is a side facing the ground to be excavated, and the attachment portion 14 is a portion for attaching to the head of a shaft portion such as an auger or a screw of an excavator. At the time of mounting, the axis of the shaft part on the excavator side and the axis of the mounting part 14 should be aligned.

The tip portion 12 has the smallest diameter at the tip portion 11, and the portion 11 is located at the center of the head 10, in other words, on the axis of the mounting portion 14. Further, the tip portion 12 has a plurality of grooves 20 on its peripheral side surface along the axial direction. Each groove 20 extends from the previous portion 11 to the end of the inclined surface or a position beyond the end. It should be noted here that the grooves 20 are arranged only on one side on the inclined surface of the tip portion 12. Therefore, considering the surface area of the tip portion 12, as is easily understood from the cross-sectional view of FIG. 2, the surface area on the side including the groove 20 is much larger than that on the other side without the groove. Therefore, when the head 10 is pushed into the ground and inserted without rotating, the head 10 receives a large ground reaction force on the side having a large surface area. The bias of the ground reaction force makes it possible to correct the direction of the head 10. That is, as shown in FIG. 1, when a force indicated by an arrow P in the axial direction is applied to the head 10, the head 10 corrects the direction as indicated by an arrow L due to the bias of the ground reaction force.

The size of the groove 20 of the tip portion 12 can be appropriately set according to the type of ground. In some cases, a plurality of heads having different groove shapes and sizes may be prepared in advance, and an appropriate head may be used according to the geology of the ground to be excavated.

In the direction correcting head 10 as described above, since the thrust force during excavation is always concentrated on the tip portion 11 located at the center of the tip portion 12, the penetrating direction is defined as a fixed direction and the variation thereof is small. Therefore, there is little meandering, and it can be effectively applied to an impact type excavator. Moreover, since the groove 20 serves as a path for excavated soil, the resistance to the tip portion 12 is reduced and the penetration force can be increased.

FIG. 3 is a side view of the direction correcting head 100 according to the second embodiment of the present invention. The direction correcting head 100 here is different from that of the first embodiment in that it further includes a clearance groove 120. There are the same number of the escape grooves 120 as the grooves 20 of the conical tip portion 12, and each groove 20 is extended in the axial direction. The grooves 20 and the escape grooves 120 communicate with each other or are continuous with each other. . The direction correcting head 100 performs the direction correction in the direction opposite to the direction correcting head 10 of the first embodiment when the groove 20 is at the same position. That is, as shown in FIG. 3, when the force of the arrow P in the axial direction is applied to the head 100, the head 100 corrects the direction as indicated by the arrow R. This is because the excavated soil is more smoothly transferred to the rear end of the head 100 through the groove 20 and the subsequent clearance groove 120 on the side where the clearance groove 120 is present, as compared to the opposite side. Specifically, the direction is corrected in the direction opposite to that of the head 10 of the first embodiment. The second direction correcting head 100 has a larger propulsion property than the first one 10, and is therefore suitable for a ground requiring a large propulsion property.

In each of the embodiments shown in the drawings, the groove 20 is provided only on one side of the tip portion 12, but the groove may be arranged all around the tip portion 12. In that case, the size of the surface area should be set appropriately by making the groove of one part larger than that of the other part, or by changing the distribution density of the groove. Further, in each of the embodiments shown in the drawings, the tip portion 12 has a conical shape, but the shape may be another pyramid shape such as a pyramid. Further, the groove 20 may have other shapes such as a linear shape and a spiral shape.

[0013]

[Effect of device]

 As described above, in the present invention, the tip portion 12 of the head 10 is formed in a pyramidal shape, and the preceding portion 11 is arranged on the axis of the mounting portion 14. Since the surface area of the tip portion 12 is made uneven by providing the groove 20 of the above, it is possible to widely apply to various types of ground by increasing the penetration force while effectively providing the function of correcting the direction. .

[Brief description of drawings]

FIG. 1 is a side view showing a first embodiment of the present invention.

FIG. 2 is a sectional view taken along line 2-2 of FIG.

FIG. 3 is a side view showing a second embodiment of the present invention.

FIG. 4 is a side view showing a conventional head of this type.

[Explanation of symbols]

 10,100 Direction correction head 11 Tip part 12 Tip part 14 Mounting part 20 Groove 120 Escape groove

Claims (3)

[Scope of utility model registration request] 1. A direction correction head located at the head of a ground excavator for defining a traveling direction by excavation, comprising a cone-shaped tip portion facing the ground to be excavated, and a shaft-shaped tip portion continuing from the tip portion. An orientation correcting head for a ground excavator, comprising a mounting portion, and the conical tip portion is configured as shown in A, B and C below. A. The center of the tip with the smallest diameter is located on the axis of the mounting portion. B. A plurality of grooves along the axial direction are provided on the peripheral side portion of the conical shape. C. When the tip portion is bisected by the plane including the axis, the surface area on one side of the bisector is larger than that on the other side. 2. The direction correcting head for a ground excavator according to claim 1, wherein the plurality of grooves are provided on only one side of the bisected portion. 3. The ground excavator according to claim 1, wherein the mounting portion also has a plurality of relief grooves along the axial direction, and each of the relief grooves communicates with the groove of the conical portion. Direction correction head.