JPS6312232Y2 - - Google Patents

Description

[Detailed explanation of the idea] The present invention relates to a screw auger.

Conventional screw augers are composed of screw blades with a central axis, and because of the central axis, the diameter of gravel that can be conveyed by the screw blades is small, and therefore the range of the gravel layer that can be excavated is narrow. It was hot. The present inventor has already proposed a screw auger that can eliminate the above-mentioned drawbacks.
As shown in FIG. 1, this screw auger is constructed of a ribbon-shaped screw blade 1 from which the central shaft, which obstructs the conveyance of gravel, has been removed. In the figure, 2 is a connecting shaft connecting the ribbon-shaped screw blade 1 and a rotary drive device (not shown), 3 is a joint thereof, 4 is a cutter bit provided at the tip of the ribbon-shaped screw blade 1, and 5
is an injection pipe for fluid (air, muddy water, cement milk, fresh water, etc.) arranged along the inner peripheral surface of the ribbon-shaped screw blade 1, and its upper end is inserted through the connecting shaft 2 and connected to the opening at the upper end of the joint part 3. 3a, and its lower end is connected to a discharge valve 6 provided on the inner peripheral surface of the ribbon-shaped screw blade 1 near the lower end. However, since the ribbon-shaped screw blade 1 does not have a central axis, it is easily bent in the vertical direction and behaves like a spring, and vibrations in the vertical direction occur particularly when excavating coarse gravel. That is, as shown in FIGS. 2a to 2c, vertical vibration occurs when the cutter bit 4 climbs over the upper surface of the coarse gravel 7 and returns to its original position. As described above, when vertical vibration occurs in the ribbon-shaped screw blade, the vibration is transmitted to the excavator body on the ground, and vibration pollution is generated in the surrounding area.

Therefore, an object of the present invention is to provide a screw auger that can eliminate the above-mentioned drawbacks.

That is, the present invention is a screw auger characterized by having screw blades formed in a ribbon shape and provided with a stay that connects the ribbon-shaped screw blades to each other in the vertical direction.

According to this configuration, the ribbon-shaped screw blades are integrated in the vertical direction and have increased rigidity, so that they no longer exhibit spring-like behavior, and therefore, it is possible to suppress the occurrence of vibrations in the vertical direction.

An embodiment of the present invention will be described below with reference to FIGS. 3 to 5. 11 is a screw auger according to the present invention, and the screw itself is composed of ribbon-shaped screw blades 12, and the ribbon-shaped screw blades 12 are connected to each other in the vertical direction by a plurality of stays 13. The stay 13 is installed at the periphery of the ribbon-shaped screw blade 12 and at, for example, every 120 degrees along the circumference (of course,
(not limited to 120°). The stay 13 integrates the ribbon-shaped screw blade 12 as a whole, increasing the rigidity, eliminating the conventional spring behavior, and thus preventing the occurrence of vertical vibration. Note that the stay 13 does not reduce the ability to take in gravel and convey the gravel upward. Reference numeral 14 denotes a connecting shaft for connecting the ribbon-shaped screw blade 12 to a rotary drive device (not shown), and is fixed to the inner periphery of the upper end portion of the ribbon-shaped screw blade 12. 15 is its joint portion. 16 is a cutter attached to the tip of the ribbon-shaped screw blade 12. Reference numeral 17 denotes a guide bit attached to the lower end of a bottomed cylindrical support 18 fixed to the center of the lower end of the ribbon-shaped screw blade 12, and is used to facilitate centering of the ribbon-shaped screw blade 12 during excavation. be. If the above guide bit 1
7, the ribbon-shaped screw blade 12 would be in a state of excavating while swinging in the horizontal direction due to the unidirectional resistance of the cutter bit 16, making positioning (centering) of the excavated hole difficult. In addition,
The cylindrical part of the support body 18 has a part remaining,
Most of the ribbon-like screw blades 12 are notched along their inner periphery. 19 is Katsutabitsu 16
A stone removal bit is attached to the lower surface of the ribbon-shaped screw blade 12 via a mounting member 20 at a position 180 degrees symmetrical to the stone removal bit, and the stone removal bit is used to slightly move the gravel buried in the soil, making it easier for the stone removal bit 16 to take in the gravel. It is for. In addition, the resistance force of the stone removal bit 19 cancels the unidirectional resistance force of the cutter bit 16, and the ribbon-shaped screw blade 12 during excavation that occurs when only the cutter bit 16 is used.
Misalignment of the centering and deformation of the ribbon-shaped screw blades 12 are prevented. Reference numeral 21 denotes an injection pipe for fluid (air, muddy water, cement milk, fresh water, etc.) arranged along the inner circumferential surface of the ribbon-shaped screw blade 12, the upper end of which is inserted through the connecting shaft 14 and connected to the upper end of the joint part 15. The lower end thereof is opened above a discharge port 18a formed at the bottom of the support 18.

In the above configuration, when excavating a shaft, the screw auger 11 is first connected and held to the rotation drive device (not shown) of the excavator, and then the screw auger 11 is inserted into the ground while rotating the ribbon-shaped screw blades 12. All you have to do is push it into. Then, fluid such as mud water is injected into the excavated surface from the injection pipe 21 via the discharge port 18a as needed. The centering of the ribbon-shaped screw blade 12 during excavation can be easily performed by the cooperation of the guide bit 17 and the stone removal bit 19. Also,
Since the ribbon-shaped screw blades 12 are integrated in the vertical direction by the stays 13, they no longer exhibit spring-like behavior, and the occurrence of vibrations in the vertical direction can be suppressed. Note that the screw auger 11 may be rotated within a cylindrical casing.

[Brief explanation of the drawing]

Fig. 1 is a side view of the conventional example, and Fig. 2 explains the state of vibration generation, where a shows the state in which the katsutabit hits the upper part of the gravel, b shows the state in which the katsutabit rides on the gravel, c is a diagram showing the state in which Katsutabitsu has climbed over the gravel, Figure 3 is a side view of an embodiment of the present invention, Figure 4 is a perspective view of the main part, and Figure 5 is a view taken from the - arrow in Figure 4. It is a diagram. DESCRIPTION OF SYMBOLS 11... Screw auger, 12... Ribbon-like screw blade, 13... Stay, 16... Cutting bit, 17... Guide bit, 18... Support body, 18a... Discharge port, 19... Stone removal bit, 2
0...Mounting member.

Claims (1)

[Scope of utility model claims] In addition to configuring the screw blades into a ribbon shape,
This screw auger is characterized by having a stay that connects the ribbon-shaped screw blades to each other in the vertical direction.