JPS59173483A - Method of detecting abrasion of cutter bit - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for detecting wear of a pull cutter pit in an excavator.

Normally, excavators such as shield excavators are not equipped with a special means to detect the wear of the cutter pit, and conventionally, the wear marks were determined by the decrease in excavation efficiency, but this was not accurate. For example, if the judgment is delayed, the cemented carbide from cutter pit 1 to the tip may fall off, damaging other cutter pits on the same trajectory.Also, even if the wear of the cutter pit is successfully detected, It is necessary to replace the cutter pit, and if the ground is poor, for example, ground improvement is required, which has the disadvantage that excavation work is interrupted for a long time, reducing excavation efficiency.

Therefore, an object of the present invention is to provide a cutter pit wear detection method that eliminates the above-mentioned drawbacks.

That is, the present invention arranges a pair of electrodes in a sealed space formed inside a cutter pit, and when the cutter pit wears out, the sealed space communicates with the outside, thereby making the pair of electrodes conductive. This method is characterized by a cutter pit wear detection method. According to this method, cutter pit wear can be accurately detected, and the cemented carbide tip can be prevented from falling off as in the conventional method, so that other cutter pits on the same trajectory can be prevented from falling off. Since damage to the cutter pit can be prevented, and since the degree of wear of the cutter pit can be known in advance, work such as ground improvement can be prepared in advance, and the time required for replacing the cutter pit can be shortened.

An embodiment of the present invention will be described below with reference to FIGS. 1 and 2. Reference numeral 1 denotes, for example, a shield excavator, in which a cutter head 4 having a cutter pit 3 on its surface is rotatably supported at the front of a shield body 2 via bearings 5 and 6. The cutter head 4 is attached to the rear end of the support tube 4a and is operatively connected to the rotational drive device 9 via a pulled ring gear A77 and a pinion 8 meshing with the ring gear 7. As shown in FIG. 2, the cutter bit 3 has a cemented carbide 3a brazed to its tip, and a hole 10 of a predetermined depth is drilled inside the cutter bit 3 from the back surface. At the same time, a capsule-shaped sealed container 12 having a sealed space 11 inside is inserted and screwed into this hole 10. Furthermore, a pair of electrodes 13.13 = are inserted into the closed space 1.1 of the closed container 12, and this pair of electrodes 13.13- is connected to the electrical wiring 1 in the cutter head 4.
4 to the control board 15. In addition, in FIG. 1, 16 is a rotary terminal, and in FIG. 2, 17 is a cutter head 4.
This is a slit for taking in earth and sand formed in the face plate 4b. Therefore, if the cutter bit 3 is worn during excavation as shown by the imaginary line in FIG. 2 and a part of the closed container 12 is damaged, groundwater will enter the closed space 11 and the pair of electrodes 13.13 will become conductive. 7ru. When the pair of electrodes 13 and 13 become conductive, an indicator lamp on the control panel 15 lights up, and wear of the cutter bit 3 is detected. In this way, the wear of the cutter bit 3 can be reliably detected, so if you detect it early, you can prepare for the ground improvement work required when replacing the cutter pit in advance, improving work efficiency. (Normally, a large number of cutter bits 3 are provided on the cutter head 4, and the sealed container 12 is provided at an appropriate position, for example, at the outermost position of the cutter bit 3.

By the way, in the above embodiment, the cutter bit 3 has a
For example, the third airtight container 12 is inserted.
As shown in the figure, if a plurality of closed containers 12 are inserted at different positions and at different depths, the wear state can be detected step by step. By inserting a plurality of closed containers 12 at different positions, it is possible to grasp the wear pattern. Further, in the above embodiment, a cutter bit for a shield excavator has been described, but it goes without saying that the present invention can also be applied to a cutter bit (cutter teeth) for an ordinary excavator.

[Brief explanation of drawings]

Fig. 1 □ is a longitudinal sectional view of one embodiment of the present invention, Fig. 2 is an enlarged sectional view of the same main part, Figs. 3 and 4 are schematic side views of the main part showing a modification, and Fig. 5 is FIG. 4 is a front view of FIG. 1... Shield excavator, 2... Shield body, 3
...Cutter bit, 4...Cutter head, 10...
- Hole, 11... Sealed space, 12... Sealed container, 13
;13'...electrode, 14...electrical wiring, 15...
Control panel agent Yoshihiro Morimoto

Claims (1)

[Claims] 1. A cutter characterized in that a pair of electrodes is arranged in a sealed space formed inside a cutter pit, and when the cutter hit wears, the sealed space communicates with the outside, thereby making the pair of electrodes electrically conductive. Pit wear detection method.