WO1988005117A1

WO1988005117A1 - Ring cutter for tunnel and shaft drilling in rock

Info

Publication number: WO1988005117A1
Application number: PCT/NO1987/000085
Authority: WO
Inventors: Stein Narvestad
Original assignee: Stein Narvestad A/S
Priority date: 1986-12-30
Filing date: 1987-12-29
Publication date: 1988-07-14
Also published as: AU1083888A; NO865330L

Abstract

Ring cutter for tunnel and shaft drilling in rock, the ring cutter (1) thereby comprising at least two ring cutter segments being secured to the rotation body (5) of the ring cutter (1) by means of tightening devices.

Description

Ring cutter for tunnel and shaft drilling in rock

The present invention is related to a ring cutter

^•T

/ for tunnel and shaft drilling in rock.

By tunnel and shaft drilling in rock increasingly large tunnel drilling machines or full face machines are used. These machines comprise idle journaled ring cutters distribut¬ ed on the surface of the cutter head, each ring cutter thereby being rotateable journaled in a separate bearing, the cutter

10 edge thereby being made of steel or comprising carbide tipped inserts .

During drillings operations the cutter edges will be wore down and the cutter rings must be replaced. This work today is time consuming as each ring cutter bearing

15 must be released from the machine, dismantled to be replaced or the cutter edge itself has to be treated. The time consump¬ tion for this replacement is very long which also means that the very expensive tunnel drilling machines have long shut down periods before they again can be placed into operation.

20

Even if the ring cutter bearings from time to time also must be replaced due to wear and tear, the ring cutters must be dismountled several times before the need exists to replace the bearings .

With the ring cutters according to the present invent¬

25 ion a substantial decrease of the shut down periods for re¬ placing the ring cutters is achieved, as there does not exists any need to remove the bearings for the ring cutters to insert new or treated ring cutters. This advantage is achieved by the features stated in the characterizing clauses of the

30 claims.

In the drawing Fig. 1 discloses one embodiment of the ring cutter according to the present invention in an axial section, Fig. 2 discloses the principal for the ring cutter according to the present invention in a second embodi-

35 ment, Fig. 3 discloses an axial section through the mounting device according to Fig. 2, Fig. 4 and 5 disclose axial sect¬ ions through the ring cutter according to the invention with the mounting device according to Fig. 2 for an embodiment with axial guldens of the ring cutter and Fig. 5 discloses a further embodiment of the axial guidens disclosed in Fig. 4.

Fig. 1 discloses on embodiment of the ring cutter according to the present invention and Fig. 2 discloses a further embodiment of the ring cutter according to the invent¬ ion, whereby Fig. 2 discloses that the ring cutter is devided, namely in two half circle shaped parts . According to the invention, the ring cutter 1 also can be devided into more than two parts .

By the embodiment in Fig. 1, the root portion 2 of the ring cutter 1, comprises a downfall shape, corresponding with a groove 3 in the rotation body 3 of the ring cutter. The groove 3 is constituted by the rotation body itself in one side and in the other side of a nut 4 which by means threads is threaded on to the rotation body 5.

When the nut 4 is threaded of the rotation body 5, the groove 3 will be widend so much that the two segments of the ring cutter 1 can be removed radially and new ring cutter segments can be inserted, whereafter the nut 4 is threaded and tightend in a suitable way to secure the ring cutter 1 in the groove 3 by locking the root portion 2 of the ring cutter 1 in the groove 3.

Fig. 2 discloses a cross section of another embodiment for securing the two segments of the ring cutter. Here the two segments of the ring cutter are together not a complete circle, but wedges 6 -are inserted diametrically to each other between the two segments , whereby the extreme phases of the segments are provided with inclined surfaces corresponding to the inclined surfaces of the wedge 6. The wedge 6 is tight- end with bolts 7 to the rotation body 5 to ensure that the ring cutter segments are secured to the rotation body.

Guidings 8 are secured to the rotation body 5 on each side of the ring cutter 1 for axial guding of the ring cutter segments. In a second embodiment a centric guide 9 is secured to the rotation body 5.

Claims

P a t e n t C l a i m s

1. Ring cutter for tunnel and shaft drilling in rock, CHARACTERIZED IN that the ring cutter (1) is made of at least two ring cutter segments and that the segments are secured to the rotation body (5) of the ring cutter (1) by means of tightening devices.

2. Ring cutter according to claim 1, CHARACTERIZED IN that the tightening devices comprise inclined surfaces abutting corresponding inclined surfaces on the segments of the ring cutter (1).

3. Ring cutter according to claim 1, CHARACTERIZED IN that the root portions (2) of the ring cutter segments in an axial section provides a dowtail shape and the rotation body (5) comprises a groove (3) with a corresponding shape, one side wall of the groove thereby being constituted by the body (5) and the other side wall being constituted by one inclined end surface of a nut ( 4 ) , whereby the nut ( 4 ) comprises threads corresponding to threads on the rotation body ( 5 ) .

4. Ring cutter according to claim 1, CHARACTERIZED IN that the ring cutter segments comprise axially inclined terminating surfaces adapted for securement to the rotation body (5) between the segments of the ring cutter (1), prefer- ably diametrically opposed.

5. Ring cutter according to claim 3, CHARACTERIZED IN that at least one guide (8, 9) being arranged on the rotat¬ ion body (5), axially abutting against the ring cutter seg¬ ments thereby preventing axial displacement of the ring cutter segments in relation to the rotation body (5).