JPH074594U - Structure of cutter bit for shield machine - Google Patents

Abstract

(57) [Summary] [Purpose] To easily and safely replace the cutter bit in a short time. [Structure] The first bit layer 11, the second bit layer 12, and the third bit layer 13 are laminated via a first adhesive layer 14 and a second adhesive layer 15.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to the structure of a cutter bit for a shield machine.

[0002]

[Prior art]

 First, a conventional cutter bit for a shield machine will be described.

In FIG. 7 and FIG. 8, a plurality of (four in the illustrated example) cutas pork 3 are radially formed on the cutter disk 2 provided at the front part of the shield machine main body 1. A plurality (three in the illustrated example) of bit holders 4 are provided on opposite sides of the cut-and-spokes 3. The bit holder 4 is integrally provided with a cutter bit 5 made of cemented carbide as shown in FIGS. 9 and 10.

The cutter bit 5 will be worn away when excavating for a long distance, and thus needs to be replaced.

[0005]

[Problems to be solved by the device]

 The exchange of the cutter bit 5 is performed by exchanging the bit holder 4, but in that case, an auxiliary construction method such as a pneumatic construction method or a freezing construction method is used to stabilize the ground, and the worker can cut the cutter disk 2 in the ground. It is common to work in front of This is problematic in terms of time, cost and safety.

An object of the present invention is to provide a structure of a cutter bit for a shield machine, which can easily and safely replace the cutter bit in a short time.

[0007]

[Means for Solving the Problems]

 According to the present invention, a cutter bit provided on a cutter disk of a shield machine via a bit holder is formed by a plurality of bit layers laminated with an adhesive layer.

A flow path reaching each adhesive layer may be formed in the bit holder, a fluid pressure may be applied to the adhesive layer via the flow path, and the adhesive layer may be peeled off to replace the bit layer.

[0009]

[Action]

 In the structure of the cutter bit for a shield machine configured as described above, the bit layer is worn by excavation and reaches the adhesive layer at the sharp edge where each bit layer joins, or becomes sufficiently thin against external force. When the crack reaches the adhesive layer due to shearing force, etc., the bit layer automatically peels off due to the reaction force during cutting and is replaced with a new bit layer below.

[0010]

【Example】

 An embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1, the bit holder 4 is integrally provided with a cutter bit generally indicated by reference numeral 10 by a publicly known means. A plurality of (three layers in the illustrated example) first bit layer 11, second bit layer 12, and third bit layer 13 are provided on the cutter bit 10 via a first adhesive layer 14 and a second adhesive layer 15. It is formed by stacking.

Next, the operation will be described.

As the excavation proceeds, the first bit layer 11 is worn away, the sharp edge E shown by the hatched portion in FIG. 2 disappears, and the first adhesive layer 14 is exposed.

When excavation is performed in this state, as shown in FIG. 3, the component force F1 parallel to the axis of the cutter disk 2 and the component force F2 in the radial direction of the reaction force F due to the excavation result in the axis line of the first bit layer 11. It acts on the side portion 11a on the side and the side portion 11b on the radial side, respectively. Therefore, the force S1 for peeling the bit acts on the side portion 11a, and the force S2 for peeling the bit acts on the side portion 11b, as shown in FIG. It is automatically peeled off, and excavation by the second bit layer 12 is started. When further excavating, the second bit layer 12 is peeled off in the same manner, and the third bit layer 13 is automatically replaced.

Further, when the first bit layer 11 is worn out by the excavation and becomes sufficiently thin, and a crack is generated by an external force to reach the first adhesive layer 14, the first bit layer 11 is automatically formed as described above. Is peeled off.

FIG. 5 shows another embodiment of the present invention, which is an example in which the cutter bit 10A is formed in two layers, that is, the first bit layer 11, the first adhesive layer 14 and the second bit layer 12.

FIG. 6 also shows another embodiment of the present invention, in which the same bit holder 4A holding the cutter bit 10 as in FIG. 1 is provided with the flow paths 16 and 17 reaching the first adhesive layer 14 and the second adhesive layer 15, respectively. It is an example of forming. In this embodiment, for example, oil is pressure-fed to the flow paths 16 and 17, and the hydraulic pressure causes the first adhesive layer 14 and the second adhesive layer 15 to be peeled off in order and the first bit layer 11 and the second bit layer 12 to be peeled off. This is an example. Therefore, the bit layer exchange timing can be selectively performed.

[0018]

[Effect of device]

 Since the present invention is configured as described above, it is possible to automatically and easily and safely replace the bit layer in a short time and improve the excavation efficiency of the shield machine.

[Brief description of drawings]

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

FIG. 2 is a side sectional view showing a state where a sharp edge is worn.

FIG. 3 is a side sectional view of an essential part for explaining the mechanism of peeling of the first bit layer.

FIG. 4 is a side sectional view showing a peeled state of the first bit layer.

FIG. 5 is a sectional side view showing another embodiment of the present invention.

FIG. 6 is a side sectional view of a main part showing another embodiment of the present invention.

FIG. 7 is a side view showing the front part of the shield.

FIG. 8 is a front view of a cutter disk.

FIG. 9 is a top view showing a conventional cutter bit.

FIG. 10 is a side sectional view of FIG.

[Explanation of symbols]

 E ... Sharp edge F ... Reaction force F1, F2 ... Component force S1, S2 ... Force to separate bits 1 ... Shield machine body 2 ... Cutter disk 3 ... Cutter spokes 4, 4A ... Bit holders 5, 10, 10A ... Cutter bits 11 ... First bit layer 12 ... Second bit layer 13 ... Third bit layer 14 ... First Adhesive layer 15 ... Second adhesive layer 16, 17 ... Flow path

Claims (1)

[Scope of utility model registration request] 1. A cutter bit structure for a shield machine, comprising: a cutter disk of a shield machine, the cutter bit being provided via a bit holder; and a plurality of bit layers laminated with an adhesive layer.