Cutter head support device, swing type cutter head, tunneling machine and construction method

Abstract

This invention provides a cutterhead support device, a swing cutterhead, a tunneling machine, and a construction method. The construction method involves providing a counter-support force along the axial direction of the cutterhead's swing center axis, supported by the tunnel walls on both sides, while the cutterhead swings to break rock, thus stabilizing its movement. This method provides stable support to the cutterhead through the tunnel walls, preventing abnormal damage to the cutting tools caused by cutterhead swing. The cutterhead support device includes a tensioning cylinder and a cutterhead connecting seat. One end of the tensioning cylinder is used to tension the tunnel walls on both sides, and the other end is connected to the cutterhead connecting seat. The cutterhead connecting seat has a cutterhead connecting part for connecting the cutterhead, which can rotate relative to the end of the tensioning cylinder used to tension the tunnel walls on both sides. The swing cutterhead includes a cutterhead and the aforementioned cutterhead support device. The tunneling machine includes the aforementioned swing cutterhead, and the cutterhead support device supports the tunnel walls on both sides through support shoes, providing stable support to the cutterhead and preventing abnormal damage to the cutting tools.

Description

Technical Field

[0001] This invention belongs to the field of tunnel boring equipment, and in particular relates to cutterhead support devices, oscillating cutterheads, tunnel boring machines and construction methods. Background Technology

[0002] Compared to drill-and-blast methods, tunnel boring machines (TBMs) offer advantages such as higher efficiency, better safety, and greater environmental friendliness, leading to their increasingly widespread application in hard rock tunnel construction. Traditional full-face TBMs can only excavate circular tunnels; to adapt to excavating small-face or rectangular tunnels, oscillating cutterheads have emerged.

[0003] Open-type TBMs (tunnel boring machines) are generally equipped with support shoes, which are located on the main beam several meters behind the cutterhead. These shoes bear the reaction forces and moments during the tunneling process through simple extension and retraction movements of hydraulic cylinders. Conventional support shoes cannot effectively stabilize the cutterhead. For oscillating cutterheads, their posture is difficult to control, easily leading to cutter damage. For example, Chinese utility model patent CN209354152U (authorization announcement date: 2019.09.06) discloses a simplified hard rock TBM, which includes an oscillating cutterhead. The oscillating cylinder's extension and retraction movement causes the cutterhead to swing up and down or left and right for rolling and rock breaking. If it moves left and right during the swing, it will put pressure on the cutters, causing significant abnormal damage, especially to the cutters on the sides. Therefore, posture control of the oscillating cutterhead is crucial for extending its lifespan.

[0004] Therefore, there is a need to provide a construction method and a cutterhead support device that can stabilize the posture of the swing cutterhead. Summary of the Invention

[0005] The purpose of this invention is to provide a construction method for a swing cutterhead tunneling machine, thereby solving the technical problem of cutter damage caused by unstable cutterhead posture during construction in existing swing cutterhead tunneling machines. A further purpose of this invention is to provide a cutterhead support device, a swing cutterhead, and a tunneling machine, thereby solving the technical problem of ineffective control of the swing cutterhead posture in existing tunneling machines.

[0006] To achieve the above objectives, the technical solution of the swing-type cutterhead tunneling machine construction method provided by the present invention is as follows:

[0007] A construction method for a swing-type cutterhead tunneling machine involves providing a counter-support force along the axial direction of the cutterhead's swing center axis, supported by the tunnel walls on both sides, while the cutterhead swings and breaks through the rock, thereby stabilizing the cutterhead's movement posture.

[0008] The beneficial effects are: the tunnel walls on both sides provide stable axial support for the cutterhead, which can maintain a stable posture when the cutterhead swings to break the rock, thereby avoiding abnormal damage to the cutter caused by the swinging of the cutterhead and extending the service life of the cutterhead.

[0009] As a further improvement, when it is necessary to adjust the excavation face left or right or up or down, the direction of the cutterhead can be adjusted by adjusting the length of the support rods on both sides.

[0010] The beneficial effect is that the steering efficiency is improved by using the cutter head to assist in steering.

[0011] To achieve the above objectives, the technical solution of the cutter head support device provided by the present invention is as follows:

[0012] A cutterhead support device includes a tensioning cylinder and a cutterhead connecting seat. One end of the tensioning cylinder is used to tension the tunnel walls on both sides, and the other end is connected to the cutterhead connecting seat. The cutterhead connecting seat is provided with a cutterhead connecting part for connecting the cutterhead. The cutterhead connecting part can rotate relative to the end of the tensioning cylinder used to tension the tunnel walls on both sides.

[0013] The beneficial effects are: during operation, the cutterhead swings with the cutterhead connecting seat, and at the same time, the hydraulic cylinders on both sides support the tunnel wall, providing axially stable counter-support force to the cutterhead connecting part, stabilizing the cutterhead posture, ensuring the stability of the cutterhead in the rock breaking process, and avoiding abnormal damage to the cutterhead cutters.

[0014] As a further improvement, the clamping cylinder includes a cylinder body and a cylinder rod, one of which is circumferentially fixed and the other is rotatable. The rotatable cylinder body and cylinder rod are provided with a cutter head connecting part, forming a cutter head connecting seat. A seal is provided between the cylinder body and the cylinder rod.

[0015] The beneficial effects are: the cylinder rod or cylinder body braces the tunnel wall, and the counter-support force of the tunnel wall acts on the cylinder body or lever through hydraulic transmission, achieving a stable support effect without affecting the oscillation of the cutter head. This design has higher integration and also ensures a stable support effect for the cutter head.

[0016] As a further improvement, a transition ring is provided between the cylinder block and the cylinder rod.

[0017] The beneficial effect is that the adapter ring facilitates the transmission or sealing connection between various parts.

[0018] As a further improvement, the cutterhead support device also includes a support base for connecting the main frame of the tunneling machine. The adapter ring is connected to the support base via a bearing. The bearing end is also provided with an axial limiting structure, and a seal is provided between the bearing and the axial limiting structure.

[0019] The beneficial effect is that, during operation, the support base is the main load-bearing component, protecting the hydraulic cylinder.

[0020] As a further improvement, the adapter ring is fixedly connected to the inner ring of the bearing, and the axial limiting structure includes caps on both sides of the bearing.

[0021] As a further improvement, the tensioning cylinders on both sides are connected to the same hydraulic power unit via valve groups.

[0022] The beneficial effect is that the valve assembly can connect the large chambers of the two supporting cylinders, ensuring that the counter-support force of the supporting cylinders is the same and improving stability.

[0023] To achieve the above objectives, the technical solution of the oscillating cutter head provided by the present invention is as follows:

[0024] A swing cutterhead includes a cutterhead connected to a cutterhead support device. The cutterhead support device includes a tensioning cylinder and a cutterhead connecting seat. One end of the tensioning cylinder is used to tension the tunnel walls on both sides, and the other end is connected to the cutterhead connecting seat. The cutterhead connecting seat is provided with a cutterhead connecting part for connecting the cutterhead. The cutterhead connecting part can rotate relative to the end of the tensioning cylinder used to tension the tunnel walls on both sides.

[0025] The beneficial effects are: during operation, the cutterhead swings with the cutterhead connecting seat, and at the same time, the hydraulic cylinders on both sides support the tunnel wall, providing axially stable counter-support force to the cutterhead connecting part, stabilizing the cutterhead posture, ensuring the stability of the cutterhead in the rock breaking process, and avoiding abnormal damage to the cutterhead cutters.

[0026] As a further improvement, the clamping cylinder includes a cylinder body and a cylinder rod, one of which is circumferentially fixed and the other is rotatable. The rotatable cylinder body and cylinder rod are provided with a cutter head connecting part, forming a cutter head connecting seat. A seal is provided between the cylinder body and the cylinder rod.

[0027] The beneficial effects are: the cylinder rod or cylinder body braces the tunnel wall, and the counter-support force of the tunnel wall acts on the cylinder body or lever through hydraulic transmission, achieving a stable support effect without affecting the oscillation of the cutter head. This design has higher integration and also ensures a stable support effect for the cutter head.

[0028] As a further improvement, a transition ring is provided between the cylinder block and the cylinder rod.

[0029] The beneficial effect is that the adapter ring facilitates the transmission or sealing connection between various parts.

[0030] As a further improvement, the cutterhead support device also includes a support base for connecting the main frame of the tunneling machine. The adapter ring is connected to the support base via a bearing. The bearing end is also provided with an axial limiting structure, and a seal is provided between the bearing and the axial limiting structure.

[0031] The beneficial effect is that, during operation, the support base is the main load-bearing component, protecting the hydraulic cylinder.

[0032] As a further improvement, the adapter ring is fixedly connected to the inner ring of the bearing, and the axial limiting structure includes caps on both sides of the bearing.

[0033] As a further improvement, the tensioning cylinders on both sides are connected to the same hydraulic power unit via valve groups.

[0034] The beneficial effect is that the valve assembly can connect the large chambers of the two supporting cylinders, ensuring the counter-support force of the supporting cylinder and improving stability.

[0035] To achieve the above objectives, the technical solution for the tunneling machine provided by this invention is as follows:

[0036] A tunneling machine includes a main unit and a supporting system. The main unit includes a swing cutterhead, a drive unit, and a main frame. The drive unit drives the cutterhead to swing. The swing cutterhead includes a cutterhead connected to a cutterhead support device. The cutterhead support device includes a tensioning cylinder and a cutterhead connecting seat. One end of the tensioning cylinder is used to tension the tunnel walls on both sides, and the other end is connected to the cutterhead connecting seat. The cutterhead connecting seat has a cutterhead connecting part for connecting the cutterhead. The cutterhead connecting part can rotate relative to the end of the tensioning cylinder used to tension the tunnel walls on both sides.

[0037] The beneficial effects are: during operation, the cutterhead swings with the cutterhead connecting seat, and at the same time, the hydraulic cylinders on both sides support the tunnel wall, providing axially stable counter-support force to the cutterhead connecting part, stabilizing the cutterhead posture, ensuring the stability of the cutterhead in the rock breaking process, and avoiding abnormal damage to the cutterhead cutters.

[0038] As a further improvement, the clamping cylinder includes a cylinder body and a cylinder rod, one of which is circumferentially fixed and the other is rotatable. The rotatable cylinder body and cylinder rod are provided with a cutter head connecting part, forming a cutter head connecting seat. A seal is provided between the cylinder body and the cylinder rod.

[0039] The beneficial effects are: the cylinder rod or cylinder body braces the tunnel wall, and the counter-support force of the tunnel wall acts on the cylinder body or lever through hydraulic transmission, achieving a stable support effect without affecting the oscillation of the cutter head. This design has higher integration and also ensures a stable support effect for the cutter head.

[0040] As a further improvement, a transition ring is provided between the cylinder block and the cylinder rod.

[0041] The beneficial effect is that the adapter ring facilitates the transmission or sealing connection between various parts.

[0042] As a further improvement, the cutterhead support device also includes a support base for connecting the main frame of the tunneling machine. The adapter ring is connected to the support base via a bearing. The bearing end is also provided with an axial limiting structure, and a seal is provided between the bearing and the axial limiting structure.

[0043] The beneficial effect is that, during operation, the support base is the main load-bearing component, protecting the hydraulic cylinder.

[0044] As a further improvement, the adapter ring is fixedly connected to the inner ring of the bearing, and the axial limiting structure includes caps on both sides of the bearing.

[0045] As a further improvement, the tensioning cylinders on both sides are connected to the same hydraulic power unit via valve groups.

[0046] The beneficial effect is that the valve assembly can connect the large chambers of the two supporting cylinders, ensuring that the counter-support force of the supporting cylinders is the same and improving stability. Attached Figure Description

[0047] Figure 1 This is a top view of the main structure of the tunneling machine in Embodiment 1 of the present invention;

[0048] Figure 2 This is a front view of the main structure of the tunneling machine in Embodiment 1 of the present invention;

[0049] Figure 3 for Figure 1 A partial sectional view in the document;

[0050] Figure 4 for Figure 3 Enlarged view of section I;

[0051] Figure 5 for Figure 4 The left view.

[0052] Explanation of reference numerals in the attached figures:

[0053] 1. Support shoe; 2. Support seat; 3. Tensioning cylinder; 3-1. Cylinder rod; 3-2. Adapter ring; 3-3. Cylinder body; 4. Cylinder connecting frame; 5. Cutter head; 6. Swing cylinder; 7. Main frame; 8. Cover; 9. Bearing; 10. Pressure ring; 11. Seal. Detailed Implementation

[0054] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only for explaining the invention and are not intended to limit the invention; that is, the described embodiments are merely some embodiments of the invention, not all embodiments. The components of the embodiments of the invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0055] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0056] It should be noted that relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any actual relationship or order between these entities or operations. Furthermore, terms such as "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the process or method that includes said element.

[0057] In the description of this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linkage" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium, or they can refer to the internal connection of two components. Those skilled in the art will understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0058] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the term "provided with" should be interpreted broadly. For example, the object "provided with" can be a part of the main body, or it can be separately arranged from the main body and connected to the main body. This connection can be a detachable connection or a non-detachable connection. Those skilled in the art can understand the specific meaning of the above terms in this invention through specific circumstances.

[0059] The present invention will be further described in detail below with reference to the embodiments.

[0060] Specific embodiment 1 of the tunneling machine provided by the present invention:

[0061] The tunneling machine structure provided in this embodiment is as follows: Figure 1As shown, the device includes a main frame 7, a swing cylinder 6, and a swing cutter head. The swing cutter head includes a cutter head 5 and a cutter head support device. The cutter head 5 is equipped with cutting tools such as roller cutters, scrapers, and cutters for rock breaking. The structure and rock breaking mechanism of the cutting tools are existing technology in this field and will not be described in detail here. The cutter head support device includes a tensioning cylinder 3, a support base 2, a support shoe 1, and a cylinder connecting frame 4. The cutter head 5 is connected to the tensioning cylinder 3. Figure 3 As shown, the tensioning cylinder 3 includes a cylinder rod 3-1, a transition ring 3-2, and a cylinder body 3-3. The support shoe 1 and cylinder rod 3-1 are fixedly connected. During use, the support shoe 1 tensions the left and right sides of the tunnel walls, increasing the support area. The cylinder body 3-3 is equipped with a cutterhead 5 connecting flange, forming a cutterhead connecting seat. The transition ring 3-2 is located between the cylinder body 3-3 and the cylinder rod 3-1. Figure 4 and Figure 5 As shown, the inner ring surface of the adapter ring 3-2 is sealed to the cylinder rod 3-1, and the outer ring surface is fixedly connected to the inner ring of the bearing 9 through the pressure ring 10. The outer ring of the bearing 9 is connected to the support seat 2, and the support seat 2 is connected to the main frame 7. The bearing 9 has caps 8 at both ends, which restrict the axial displacement of the bearing 9. Seals 11 are provided between the caps 8, the bearing 9, and the pressure ring 10. During operation, the cylinder rod 3-1 extends outward, the support shoe 1 is pressed against the tunnel wall, and the cylinder body 3-3 rotates coaxially with the cylinder rod 3-1, realizing the up-and-down swinging motion of the cutter head 5.

[0062] like Figure 1 and Figure 2 As shown, cylinder lugs are provided on both the upper and lower sides of the cylinder body 3-3. One end of the swing cylinder 6 is hinged to the cylinder lug, and the other end is fixed to the main frame 7.

[0063] Furthermore, the left and right tensioning cylinders 3 are fixedly connected by cylinder connecting brackets 4 and connected to the same hydraulic power unit through valve groups. The large chambers of the two tensioning cylinders 3 can be connected through the valve groups to achieve balanced counter-support force.

[0064] The operating principle of the oscillating cutterhead of the tunneling machine in this embodiment is as follows:

[0065] The left and right side tensioning cylinders 3 apply pressure, the cylinder rods 3-1 extend outwards, and the support shoes 1 tighten the tunnel wall. The support base 2 supports the tensioning cylinders 3 through the bearings 9. Driven by the upper and lower side swinging cylinders 6, the cutterhead 5 rotates around the central axis of the tensioning cylinders 3 via the cylinder body 3-3. By coordinating different extension and retraction amounts of the swinging cylinders 6, the cutterhead 5 swings repeatedly, thereby breaking the rock mass. During the swinging of the cutterhead 5, the support shoes 1 transmit the counter-support force from the tunnel wall to the cylinder body 3-3 through hydraulic force, allowing the cylinder body 3-3 to rotate stably. This stabilizes the left and right posture of the cutterhead 5, avoids abnormal damage to the cutters, and extends the service life of the cutterhead 5. By adjusting the load on the tensioning cylinders 3, the support shoes 1 can slide on the tunnel wall, allowing the entire cutterhead support device to move forward with the tunneling machine. The support shoes 1 can also remain close to the tunnel wall. After completing one stroke of tunneling, the support shoes 1 are retracted, and the tunneling machine moves forward. When a stable support reaction force is required, the large chambers of the two tensioning cylinders 3 can be connected through the valve group. When it is necessary to adjust the left and right position of the cutter head 5, the single tensioning cylinder 3 can be controlled to achieve different extension and retraction amounts to assist in the orientation adjustment of the cutter head 5.

[0066] The specific embodiment 2 of the tunneling machine provided by this invention differs from embodiment 1 mainly in that: in embodiment 1, the cutterhead 5 swings up and down under the action of the swing cylinder 6, and the tensioning cylinder 3 tensions the left and right sides of the tunnel walls. In this embodiment, the cutterhead swings left and right under the action of the swing cylinder, and the tensioning cylinder tensions the upper and lower sides of the tunnel walls, providing a counter-support force in the swing axis direction for the cutterhead.

[0067] The specific embodiment 3 of the tunneling machine provided by this invention differs from embodiment 1 mainly in that: in embodiment 1, the cutterhead connecting seat is formed by a cylinder body 3-3. In this embodiment, the cutterhead connecting seat is a slewing bearing structure, its outer ring is rotatable and has a cutterhead connecting part, and its inner ring is fixedly connected to one end of the tensioning cylinder. The tunnel wall counter-support force acts on the cutterhead connecting seat through the tensioning cylinder, thereby stabilizing the cutterhead posture.

[0068] The specific embodiment 4 of the tunneling machine provided by this invention differs from embodiment 1 mainly in that: in embodiment 1, the cylinder body 3-3 of the cutterhead support device rotates relative to each other, and the cylinder rod 3-1 is connected to the support shoe 1. In this embodiment, the cylinder body is connected to the support shoe, and the cylinder rod rotates relative to each other.

[0069] The specific embodiment 5 of the tunneling machine provided by the present invention differs from embodiment 1 mainly in that: in embodiment 1, the clamping cylinder 3 of the cutterhead support device includes a transition ring 3-2. In this embodiment, the clamping cylinder does not include the transition ring, and the cylinder body and cylinder rod are sealed together.

[0070] The specific embodiment 6 of the tunneling machine provided by the present invention differs from embodiment 1 mainly in that: in embodiment 1, the cutterhead support device includes a support base 2. In this embodiment, the support base is not included, and the cutterhead and cutterhead support device are supported by an up-and-down swing cylinder. During operation, side support shoes provide auxiliary support.

[0071] The specific embodiment 7 of the tunneling machine provided by the present invention differs from embodiment 1 mainly in that: in embodiment 1, the cylinder rod 3-1 is connected to a support shoe 1. In this embodiment, no support shoe is provided, and the cylinder rod is directly used to tighten the tunnel wall.

[0072] The specific embodiment 8 of the tunneling machine provided by the present invention differs from embodiment 1 mainly in that: in embodiment 1, swing cylinders 6 are provided on both the upper and lower sides of the cylinder body 3-3. In this embodiment, only the lower side is provided with a swing cylinder, and the cutterhead can also be driven to swing by the extension and retraction adjustment of the lower swing cylinder.

[0073] Specific embodiments of the cutter head support device in this invention:

[0074] The embodiments of the cutterhead support device are those described in any of the embodiments 1 to 7 of the tunneling machine described above, and will not be specifically described here.

[0075] Specific embodiments of the oscillating cutter head in this invention:

[0076] A swing cutterhead, including a cutterhead connected to a cutterhead support device as described in any of the embodiments 1 to 7 of the tunneling machine described above, which will not be further described here.

[0077] Specific embodiments of the construction method of the swing-type cutterhead tunneling machine in this invention:

[0078] The construction method of the swing-type cutterhead tunneling machine involves providing a counter-support force along the axial direction of the cutterhead's swing center axis, supported by the tunnel walls on both sides, while the cutterhead swings and breaks through the rock, thus stabilizing the cutterhead's movement posture. The specific construction process can be achieved using the tunneling machine described in any of the above embodiments 1 to 8, and its principle is as described in the operating principle of embodiment 1, and will not be further elaborated here.

[0079] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still make modifications to the technical solutions described in the foregoing embodiments without creative effort, or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A cutterhead support apparatus, characterized by, The supporting device comprises a supporting oil cylinder, a cutter head connecting seat and a supporting seat for connecting a main frame of a tunneling machine, one end of the supporting oil cylinder is used for supporting two sidewall holes of a tunnel, the other end of the supporting oil cylinder is connected with the cutter head connecting seat, the cutter head connecting seat is provided with a cutter head connecting part for connecting a cutter head, the cutter head connecting part is rotatable relative to the supporting oil cylinder and is used for supporting one end of the two sidewall holes of the tunnel, an axis of rotation of the cutter head connecting part coincides with an axis of the supporting oil cylinder, so that the supporting oil cylinder provides a counter supporting force on an axis of rotation of the cutter head, the supporting oil cylinder comprises a cylinder body and a cylinder rod, a connecting ring is arranged between the cylinder body and the cylinder rod, the cylinder rod is fixed in a circumferential direction, the cylinder body is rotatable, the cylinder body is provided with the cutter head connecting part and forms the cutter head connecting seat, a sealing element is arranged between the cylinder body and the cylinder rod, the connecting ring is connected with the cylinder body through bolts, the connecting ring is connected with the supporting seat through a bearing, an axial limiting structure is further arranged at an end of the bearing, and a sealing element is arranged between the bearing and the axial limiting structure.

2. The cutterhead support apparatus of claim 1, wherein The connecting ring is fixedly connected with an inner ring of the bearing, and the axial limiting structure comprises covers arranged at two ends of the bearing.

3. The cutterhead support apparatus of claim 1 or 2, wherein, The two supporting oil cylinders are connected in a same hydraulic power unit through a valve group.

4. A swing blade, comprising a blade, characterized in that The cutter head is connected with the cutter head supporting device as claimed in any one of claims 1 to 3.

5. A roadheader comprising a main machine and a rear matching system, characterized in that The main frame comprises the oscillating cutter head as claimed in claim 4, a driving device and a main frame, and the driving device is used for driving the cutter head to oscillate.

6. A method of construction of a swing-toothed cutterhead tunneling machine, characterized in that, The cutter head supporting device as claimed in any one of claims 1 to 3 is applied, while the cutter head is oscillating to break rocks, the two sidewall holes of the tunnel are used as supports, and a counter supporting force along an axis of rotation of the cutter head is provided to the cutter head, the counter supporting force acts on the axis of rotation of the cutter head, and the movement posture of the cutter head is stabilized.

7. The swing cutterhead tunneling machine construction method of claim 6, wherein, When it is necessary to adjust the excavation face leftward and rightward or upward and downward, the cutter head is adjusted in a direction through adjustment of lengths of the two supporting rods.

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