A cutter head with variable excavation diameter

Abstract

The present invention discloses a cutter head capable of changing the excavation diameter, which is characterized in that it includes cutter blades with cutting knives for rotary cutting of the soil on the excavation surface. The cutter blades are installed on the drive shaft of the drive device through a pin shaft device. A center cutter is arranged at the center of the drive shaft. When the cutter head cuts the soil, the reaction force received by the cutter blades is transmitted to the drive shaft through the contact surface between the cutter blades and the center cutter. There is also a fixed shaft for positioning between the cutter blades and the drive shaft to ensure the stability of the cutter blades during normal cutting of the cutter head. The fixed shaft can be driven to expand and contract by an oil cylinder or other means. The drive device with the drive shaft is installed on the shield body. A limiting rod is arranged on the shield body and extends out when the cutter head needs to reduce the diameter. The limiting rod can be driven to expand and contract by an oil cylinder or other means. By using the present invention to change the excavation diameter of the cutter head, it is used for a retractable pipe jacking machine, with a simple and reliable structure and low cost.

Description

Technical Field

[0001] The present invention relates to the field of tunnel construction equipment, and more specifically, to a cutter head for tunnel boring with a variable excavation diameter. Background Art

[0002] Pipe jacking construction is a relatively mature method for laying underground pipelines in China. However, in actual construction, it is often affected by many factors, such as out-of-control deviation correction, serious deviation of the pipeline axis or elevation, insufficient bearing capacity of the rear wall, excessive frictional resistance of the pipe wall, sudden change of geological conditions, mechanical failures, encountering unknown obstacles in the front, etc., which cause the tunneling machine to be unable to continue tunneling. At this time, whether it is to abandon the equipment or dig out the equipment, a large amount of manpower and material resources are wasted. In addition, there are some projects where equipment recovery cannot be carried out at the target location. Therefore, retractable pipe jacking machines have been increasingly used. The variable diameter cutter head is an important part of the retractable pipe jacking machine. When the equipment needs to be withdrawn, the diameter of the cutter head can be reduced so that it can smoothly pass through the shield shell. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide a cutter head with a variable excavation diameter, which is used for a retractable pipe jacking machine by changing the excavation diameter of the cutter head, and has a simple and reliable structure and low cost.

[0004] In order to achieve the above technical effects, the technical solution adopted by the present invention is:

[0005] A cutter head with a variable excavation diameter, characterized in that it includes a shield body, a driving device installed on the shield body, and cutter blades with cutting knives for rotary cutting of the soil on the excavation surface; the cutter blades are rotatably installed on the driving shaft of the driving device through a pin shaft device, and after the cutter blades rotate around the pin shaft device, there is an unfolded state that makes the cutter head diameter the largest and a closed state that makes the cutter head diameter the smallest; a fixed shaft is provided between the cutter blade and the driving shaft, and the fixed shaft can be driven to expand and contract by a driver; a positioning hole is provided on the back of the center end of the cutter blade, and the positioning hole of the cutter blade in the unfolded state is exactly in front of the fixed shaft. After the fixed shaft extends out, it can be inserted into the positioning hole for limiting and fixing the cutter blade in the unfolded state; a limiting rod is also provided on the shield body, and the limiting rod can also be driven to expand and contract by a driver; the extended limiting rod is used for limiting and fixing the cutter blade in the closed state.

[0006] Further, a center cutter is provided at the center of the driving shaft.

[0007] Further, there are 3 cutter blades, and the 3 cutter blades are annularly arranged around the center line of the cutter head.

[0008] Further, the cutter blade is installed on the driving shaft through a detachable pin shaft device.

[0009] Further, when the cutter blade is in the unfolded state, the side wall of the central end of the cutter blade abuts against the outer wall of the central cutter to transmit the tunneling torque.

[0010] Further, when the cutter blade is in the folded state, the inner wall of the far end of the cutter blade abuts against the outer wall of the central end of the adjacent cutter blade.

[0011] Further, the cutting tool is detachably mounted on the cutter blade.

[0012] Further, a limiting hole is provided on the back surface of the cutter blade between the far end and the central end. A driving rod is installed on the shield body. The driving rod can be driven by a driver to expand and contract. After the cutter blade rotates a certain angle, the driving rod is driven by the driver to extend and just insert into the limiting hole, so as to limit and fix the cutter blade in a certain state between the unfolded state and the folded state. Among them, the working principle of the limiting hole and the driving rod is the same as that of the positioning hole and the fixed shaft.

[0013] Compared with the prior art, the beneficial effects of the present invention are as follows: By installing a rotatable cutter blade on the driving shaft of the driving device, the excavation diameter of the cutter head is changed by the rotation of the cutter blade, which is used for a retractable pipe jacking machine, and the structure is simple and reliable, and the cost is low. Description of the Drawings

[0014] Figure 1 The front view when the cutter head has a normal excavation diameter;

[0015] Figure 2 is Figure 1 The sectional view taken along the line A-A in

[0016] Figure 3 is Figure 1 The sectional view taken along the line B-B when the fixed shaft extends in

[0017] Figure 4 is Figure 1 The sectional view taken along the line B-B when the fixed shaft retracts in

[0018] Figure 5 The front view when the excavation diameter of the cutter head is reduced;

[0019] Figure 6 is Figure 5 The sectional view taken along the line C-C in

[0020] Figure 7 The schematic diagram of the equipment withdrawal after the excavation diameter of the cutter head is reduced.

[0021] The reference numerals in the figure and their corresponding component names are:

[0022] 1. Cutter blade, 2. Pin shaft device, 3. Drive shaft, 4. Center cutter, 5. Shield body, 6. Fixed shaft, 7. Limit rod. Detailed implementation manners

[0023] To understand the technical solution provided by the present invention more clearly, the present invention will be further described below in conjunction with the accompanying drawings and specific embodiments. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments.

[0024] As Figure 1 and Figure 2 shown, a cutter head capable of changing the excavation diameter provided by the present invention includes 3 cutter blades 1 with cutting tools for rotary cutting of the soil on the excavation surface. The cutter blades 1 are rotatably installed on the drive shaft 3 through the pin shaft device 2 and are distributed in a circular array. A center cutter 4 is provided at the center of the drive shaft 3. The excavation diameter of the cutter head , the outer diameter of the shield body 5 is , and the inner diameter of the outer shell of the shield body 5 is When the pipe jacking machine is normally tunneling, The larger excavation diameter of the cutter head can ensure the smooth tunneling of the equipment. At this time, the side of the cutter blade 1 close to the center of the cutter head is in close contact with the center cutter 4. The torque provided by the driving device is transmitted to the cutter blade 1 through the drive shaft 3 and the center cutter 4. The cutting tools on the cutter blade 1 cut the soil, and the cutter head tunnels normally.

[0025] As shown in the attached Figure 3 and Figure 4 figures, a fixed shaft 6 is also provided on the drive shaft 3. When the fixed shaft 6 extends, the cutter blade 1 is relatively fixed to the drive shaft 3, ensuring the stability of the cutter blade 1 during cutting. When the cutter head needs to reduce the diameter, the fixed shaft 6 retracts, and the cutter blade 1 can rotate around the pin shaft device 2.

[0026] As shown in the attached Figure 5 and Figure 7 figures, when the fixed shaft 6 retracts and the limit rod 7 installed on the shield body 5 extends, the cutter head starts to rotate in the reverse direction. The cutter blade 1 is limited by the limit rod 7, and the cutter blade 1 starts to rotate around the pin shaft device 2 as the center, and the excavation diameter gradually decreases. Finally, the diameter of the cutter head decreases to And , at this time, the inner and outer shells of the shield body 5 are separated and staggered, and the inner shell of the shield body 5 withdraws from the outer shell of the shield body 5 together with the driving device, the cutter head and other equipment. After all the equipment except the outer shell of the shield body 5 is completely withdrawn from the tunnel, subsequent operations such as secondary lining can be carried out.

[0027] The present invention is not limited to the above specific implementation manners. For those of ordinary skill in the art, starting from the above concepts, without creative labor, all kinds of transformations made fall within the protection scope of the present invention.

Claims

1. A cutter head capable of changing the excavation diameter, characterized in that, it includes a shield body (5), a driving device installed on the shield body (5), and cutter blades (1) with cutting knives for rotary cutting of the soil on the excavation surface; the cutter blades (1) are rotatably installed on the driving shaft (3) of the driving device through a pin shaft device (2), and after the cutter blades (1) rotate around the pin shaft device (2), there is an unfolded state in which the cutter head diameter is the largest and a folded state in which the cutter head diameter is the smallest; a fixed shaft (6) is provided between the cutter blade (1) and the driving shaft (3), and the fixed shaft (6) can be driven by a driver to expand and contract; a positioning hole is provided on the back of the center end of the cutter blade (1), and the positioning hole of the cutter blade (1) in the unfolded state is exactly in front of the fixed shaft, and after the fixed shaft extends out, it can be inserted into the positioning hole for limiting and fixing the cutter blade in the unfolded state; a limiting rod (7) is also provided on the shield body (5), and the limiting rod (7) can also be driven by a driver to expand and contract; the extended limiting rod (7) is used for limiting and fixing the cutter blade (1) in the folded state; a center cutter (4) is provided at the center of the driving shaft (3); the cutter blade (1) is installed on the driving shaft (3) through a detachable pin shaft device (2).

2. A cutter head capable of changing the excavation diameter according to claim 1, characterized in that, there are 3 cutter blades (1), and the 3 cutter blades (1) are annularly arrayed around the center line of the cutter head.

3. A cutter head capable of changing the excavation diameter according to claim 2, characterized in that, when the cutter blade (1) is in the unfolded state, the side wall of the center end of the cutter blade (1) abuts against the outer wall of the center cutter (4) to transmit the tunneling torque.

4. A cutter head capable of changing the excavation diameter according to claim 2, characterized in that, when the cutter blade (1) is in the folded state, the inner wall of the far end of the cutter blade (1) abuts against the outer wall of the center end of the adjacent cutter blade, and the outer wall of the far end of the cutter blade (1) abuts against the side wall of the limiting rod.

5. A cutter head capable of changing the excavation diameter according to claim 1, characterized in that, the cutting knife is detachably installed on the cutter blade (1).

6. A cutter head capable of changing the excavation diameter according to claim 1, characterized in that, a limiting hole is further provided on the back of the cutter blade (1) between the far end and the center end, a driving rod is installed on the shield body (5), the driving rod can be driven by a driver to expand and contract, and after the cutter blade (1) rotates a certain angle, the driving rod is driven by the driver to extend out and just insert into the limiting hole for limiting and fixing the cutter blade in a certain state between the unfolded state and the folded state.

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