JPH0545625Y2 - - Google Patents

Description

[Detailed description of the invention] (Technical field to which the invention belongs) The present invention relates to a ground improvement stirring and mixing device, that is, a device that stirs and mixes ground soil and a solidification material in order to improve soft ground.

(Problems with the invention and its features) In a soil improvement stirring and mixing device that has stirring blades installed in multiple stages at the lower end of the rotating shaft, the soil between the stirring blades in adjacent stages rotates together with the stirring blades, resulting in a good stirring and mixing effect. It may not be done.

In order to solve the above-mentioned problems, the rotating shaft is double-layered, with stirring blades protruding radially in multiple stages at the lower end of the inner rotating shaft, and the inner rotating shaft is placed at the lower end of the outer rotating shaft. It is already known that stirring blades are positioned between adjacent stage stirring blades and protrude inward so that the inner and outer rotating shafts rotate in opposite directions (Japanese Patent Application Laid-open No. 165416-1982). In this conventional example, the transmission mechanism becomes complicated and large-scale because both the inner and outer rotating shafts are rotated in opposite directions, and stones, etc. If hard foreign matter becomes clogged, the stirring blades may be damaged.

In view of the above circumstances, the present invention is an improvement over the conventional example, and its structural features are as described in the claims of the utility model registration.

As is clear from its characteristic structure, in the device of the present invention, the outer shaft loosely fitted into the rotating inner shaft is not driven to rotate, but is kept in a state where rotation is inhibited until a predetermined force is applied at the required time. It's getting old.

(Specific explanation of the invention based on drawings) In the drawings showing an embodiment of the invention, the rotating inner shaft 1 is a motor 3 suspended by a rope 2 so as to be able to rise and fall freely.
The stirring blades 5 are connected to each other via a suitable transmission mechanism 4, and protruding from the lower end thereof are stirring blades 5 extending in the radial direction in multiple stages (three stages in the case of the figure).

Reference numeral 6 denotes an outer shaft loosely fitted to the inner rotary shaft 1, and an appropriate number of arms 8 (two on the left and right in the figure) extending outward from a bearing portion 7 at the lower end extend to a lower bearing portion 9. This arm 8 also has stirring blades 10 protruding in multiple stages, and each stirring blade 10 of this outer shaft 6 is attached to the rotating inner shaft 1
It is located between the stirring blades 5, 5 of adjacent stages, and protrudes inward, that is, toward the rotating inner shaft 1 side.

Although it is preferable that the rotation directions of the inner stirring blade 5 and the outer stirring blade 10 be inclined in the same direction with respect to the horizontal plane, they may be tilted in different directions.

The upper end of the outer shaft 6 is located at a bearing portion 1 below the transmission mechanism 4.
The brake 1, such as a band brake or a disc brake, is mounted on this supporting part in a freely rotatable state through the support part 1, such as a band brake or a disc brake, to bring the outer shaft 6 into a predetermined braking state.
2 is provided.

In addition, 13 is a stirring blade attached to the tip of the rotating inner shaft 1 (below the bearing part 9) and extending upward along the outside of the arm 8, and 14 is a digging tooth attached to the tip of the rotating inner shaft 1. , 15 are discharge holes for solidifying material.

When performing ground improvement using the above device, for example, when penetrating into the ground, the solidifying material is discharged, the rotating inner shaft 1 is rotated, and the outer shaft is left in a free rotation state, and when pulling out, the solidifying material is discharged. No material is discharged,
The inner rotary shaft 1 is rotated, and the outer shaft is kept in a predetermined braking state. At the time of this pulling out, the above-mentioned co-rotation phenomenon is prevented by the stirring blade 10 in the rotation inhibited state, and the ground soil and the solidification material are reliably stirred and mixed. If a hard foreign object such as a stone is caught between the stirring blade 5 and the stirring blade 10 during the work, and a rotational force is applied from the stirring blade 5 to the stirring blade 10, this force will be applied to the outer shaft. When the braking force acting on the stirring blade 6 is exceeded, the stirring blade 10 rotates together with the stirring blade 5 while being braked, and the foreign matter comes out from between the stirring blade 5 and the stirring blade 10, so that the stirring blade 5 This prevents damage to the stirring blades 10.

(Effects of the invention) Since the device of the present invention is as described above, it is possible to effectively and reliably stir and mix the ground soil and the solidification material using a relatively simple and small-scale rotation drive mechanism, and it is possible to effectively and reliably stir and mix the ground soil and the solidification material. Even if a hard foreign object such as a stone is caught between the stirring blades, the stirring blades will not be damaged.

[Brief explanation of the drawing]

The drawing is a partially sectional side view of an embodiment of the present invention. 1... Rotating inner shaft, 5... Stirring blade, 6... Outer shaft,
10... Stirring blade, 12... Brake,...

Claims (1)

[Scope of utility model registration request] Stirring blades are provided in multiple stages protruding from the lower ends of the rotating inner shaft and the outer shaft loosely fitted into the rotating inner shaft, and the stirring blades at each stage of the outer shaft are arranged between the stirring blades at adjacent stages of the rotating inner shaft. 1. A soil improvement stirring and mixing device which projects inward and has a brake attached to its outer shaft for changing from a free rotation state to a predetermined braking state.