CN102155238A - Exchangeable blade type center cutter for shield machine - Google Patents

Abstract

The invention belongs to the technical field of excavation machinery, and relates to a center cutter for a replaceable blade type shield machine, comprising a blade seat, a center cutter block and three side cutters, and the blade seat is provided with a center cutter block positioning column and three tool holders , the middle of the positioning column is provided with a central knife block positioning hole, the bottom of the central knife block is fixedly connected to the blade seat, and the end of the positioning column is fixedly connected with a tapered boss, and the tapered boss is provided with an inner hole. The size of the inner hole of the table and the positioning hole of the center knife block is matched with the size of the center knife block; three knife holders are arranged around the center knife block positioning column, and each knife holder is provided with a slot for fixedly connecting the side knife. Each side knife is provided with positioning holes, which are fixedly connected to the slots of the three knife holders by bolts, and the three knife arms formed by the side knife and the knife holder form an included angle of 120° with each other. The invention has good stability during the excavation process, high impact resistance and wear resistance, easy operation of blade replacement, avoids waste of resources, saves construction costs, and has high economic value.

Description

A center knife for a replaceable blade type shield machine

technical field

The invention belongs to excavation machinery accessories, in particular to a shield machine cutter.

Background technique

At present, the shield machine is more and more widely used in underground engineering. As one of the key components of the shield machine, the cutter head device will directly affect the performance and efficiency of the shield machine. The reasonable selection and layout of various knives on the cutter head is an important content to be considered in the design process of the cutter head. The center knife is the frontmost tool of the shield machine, and its service life plays a very important role in the entire cutter head system. The service life of the center knife has a direct relationship with its own structure and installation method.

In the existing shield machine cutter head system design, the center knife used is generally welded to the bottom plate of the shield machine, and is connected with other tools on the shield machine to complete the excavation work through bolt connection. The structure of the center knife is generally fishtail-shaped, and two knife arms are used in a row, with the center line of the knife head as the axis of symmetry, forming an axisymmetric structure; at present, some staff in related fields have proposed a relatively stable knife A new structure with arms in a "Y" shape. However, most of the current shield machine equipment adopts the connection form of the center knife arm as welding, that is, it is a non-detachable connection, resulting in the non-replaceable blade, which has very high requirements on the performance of the alloy material on the center knife; in the knife arm In the case of unbalanced wear, if the tool wear is not corrected, the diffuse wear of each tool arm of the center tool will be intensified, which will have a significant impact on the entire tool head system and even the tunneling system; if the entire tool is replaced, construction will inevitably be increased cost, resulting in waste of resources.

Contents of the invention

The purpose of the present invention is to overcome the deficiencies of the prior art and provide a center knife for a shield machine with a reasonable structure and replaceable blades. Technical scheme of the present invention is as follows:

A center knife for a replaceable blade type shield machine, including a blade seat, a center knife block and three side blades, the center knife block positioning column and three knife holders are arranged on the blade seat, and the middle part of the positioning column is provided with The positioning hole of the center knife block, the bottom of the center knife block is fixedly connected to the blade seat, and the end of the positioning column is fixedly connected with a tapered boss, and the tapered boss is provided with an inner hole, the inner hole of the boss and the center knife block The size of the positioning hole is matched with the size of the central knife block; three knife holders are arranged around the positioning column of the central knife block, and each knife holder is provided with a slot for fixedly connecting the side blades, and the three side knives are provided with The positioning holes are respectively fixedly connected in the slots of the three knife holders by bolts, and the three knife arms formed by the side blade and the knife holder form an included angle of 120° with each other.

As a preferred embodiment, the central knife of the present invention has a rectangular cross-section of the central knife block, and the cross-sections of the central knife block positioning hole and the inner hole of the tapered boss are rectangular; a hard alloy block is fixed on the top of the central knife block, and The surface of the unfixed hard alloy block at the top of the center knife block, the front end of the tool holder and the outer surface of the boss are all provided with a wear-resistant layer; a threaded hole is provided at the center of the bottom of the center knife block, and a positioning hole is machined on the blade seat. The positioning hole coaxial with the column is used to connect and position the central cutter block on the insert seat through screws.

On the one hand, the cutter of the present invention makes each cutter arm receive uniform force, and the working resistance is small, which effectively improves the wear resistance, vibration resistance and impact resistance performance of the center cutter, and has the advantages of long service life, stable load bearing, and high-efficiency excavation; on the other hand, On the one hand, the traditional fixed knife arm is decomposed into two detachable parts, which makes it possible to replace the worn blade in time, effectively controls the spread of wear, avoids the waste of resources, and has the advantages of maintaining stable load, good economy, and easy operation. Compared with the general center knife, it has a wider application prospect.

Description of drawings

Figures 1-1 to 1-2 are schematic diagrams of the design and assembly structure of the present invention.

Fig. 2 is a schematic diagram of the structure of the edge blade of the present invention (after the cemented carbide block is welded).

Figures 3-1 to 3-2 are schematic diagrams of the structure of the central knife block of the present invention.

Figures 4-1 to 4-2 are schematic diagrams of the structure of the blade seat of the present invention.

Figure 5-1 to Figure 5-3 are the top view, front view and bottom view of the blade seat of the present invention.

Detailed ways

The principle structure and specific implementation of the present invention will be further described below in conjunction with the accompanying drawings.

The present invention provides a replaceable blade-type central knife mainly consisting of a blade seat 1, a blade (including side blades 2 and a central knife block 8) and a cemented carbide block (a side blade cemented carbide block 12 and a central knife block cemented carbide block) 14) consists of three parts. The hard alloy block is connected to the blade by special welding to form a non-detachable weld, which has high impact resistance, wear resistance and vibration resistance. On the one hand, a number of positioning holes 13 are processed on the side blade 11, and the side blade is positioned on the corresponding knife of the blade seat through bolt connection (as shown in the accompanying drawings, the bolt 3, the gasket 4, the nut 5 and the bolt connection hole 21) On frame 18, form knife arm. The three cutter arms are evenly distributed on the circumference at an included angle of 120°. This structural form has strong load-bearing stability and is also of great help to the improvement of the driving efficiency of the entire cutter head. The side blades welded with carbide blocks become replaceable components for the entire center knife. On the other hand, the center cutter block 15 is different from the past in that its cross section is processed into a rectangle corresponding to the installation position 20 on the blade seat, and such shape plays a good role in the circumferential positioning of the center cutter block. A cemented carbide block is welded on the top of the central knife block, which is a non-detachable connection and can withstand large impacts. The local force on the top is relatively uniform, and the wear resistance is greatly improved. Threaded hole 16 is machined at the center of the bottom of the center cutter block, which is positioned on the blade holder by screw connections (such as screw 9, gasket 10 and positioning hole 19 as shown), and the positioning accuracy is higher. In order to strengthen the stability of the central cutter block and avoid the retention of slag at the front end, a tapered boss 7 is processed. The center of the boss is processed with a circumferential positioning hole with a rectangular cross section, and the circumferential processing is used for screw connection (as shown in the figure) Screw 6 and threaded hole 22) axial positioning hole. The boss is directly connected to the insert seat, fixed on the outer periphery of the center block, and the rigidity of the center block is further improved. After all the parts of the center cutter are assembled on the blade seat, the center cutter is connected to the cutterhead by the positioning hole 17, and along with the rotation of the cutterhead, the excavation work of the center cutter is completed. When it is detected that the wear of the center knife is more serious and needs to be replaced, only the corresponding blades that cause the increased wear are required to be disassembled and replaced. In the present invention, the surface of the unfixed cemented carbide block 14 at the top of the central knife block 8, the front end of the knife holder and the outer surface of the boss 7 are all covered with a wear-resistant layer. The central knife has good stability during the excavation process, high impact resistance and wear resistance, easy operation of blade replacement, avoids waste of resources, saves construction costs, and has high economic value.

Claims (4)

1. replaceable blade chip shield machine center cutter, comprise blade bearing, center cutter piece and three limit cuttves, it is characterized in that, described blade bearing is provided with center cutter piece reference column and three knife rests, the middle part of reference column is provided with center cutter piece locating hole, and the bottom of center cutter piece is fixedly connected on the blade bearing, is fixedly connected with cone boss in the end of reference column, cone boss is provided with endoporus, and the size of boss endoporus and center cutter piece locating hole and the size of center cutter piece cooperatively interact; Three knife rests are arranged at the periphery of center cutter piece reference column, offer the line of rabbet joint of fixedly connected limit blade on each knife rest, be provided with locating hole on three limit cuttves, be bolted to connection respectively in the line of rabbet joint of three knife rests, three tool arms by limit blade and knife rest constitute become 120 ° of angles each other.

2. cutter according to claim 1 is characterized in that, the cross section of center cutter piece is a rectangle, and the cross section of center cutter piece locating hole and cone boss endoporus is rectangle.

3. cutter according to claim 1 and 2 is characterized in that, is fixed with hard alloy blocks on center cutter piece top, and fixedly surface, knife rest front end and the boss external surface of hard alloy blocks part are provided with wearing layer on center cutter piece top.

4. according to any described cutter of claim 1 to 3, it is characterized in that, be provided with screwed hole, on blade bearing, be processed with the locating hole coaxial, the connection of center cutter piece is positioned on the blade bearing by screw with reference column at the bottom centre place of center cutter piece.

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