Longitudinal planetary hob cutter head device for triangular section excavation

Abstract

The invention relates to a longitudinally-arranged planetary hob cutter head device for triangular section excavation. The longitudinally-arranged planetary hob cutter head device comprises a base. The rotating axis of the longitudinal cutter head body is parallel to the expected tunneling direction, and the longitudinal cutter head body is rotatably supported on the base; the hobbing cutter is rotatably mounted on the outer peripheral surface of the longitudinal cutter head body; the planetary transmission mechanism is configured to drive the base to execute a compound planetary motion, and the compound planetary motion comprises the steps that the base is driven to rotate around a fixed first axis; the base is driven to rotate around the central axis of the base; the longitudinally-arranged cutter head body is adopted as a single hob bearing structure, the base is driven to move through a planetary mechanism, the overall structure is extremely compact, the number of moving parts is small, a transmission chain is short, the highly-integrated design brings excellent structural rigidity and impact resistance, and the cutter head is very suitable for the high-load working condition of a hard rock stratum; the problem that a complex structure is insufficient in reliability in hard rock is solved.

Description

Technical Field

[0001] This invention relates to the field of tunneling construction technology, and specifically to a longitudinally mounted planetary cutterhead device for triangular cross-section excavation. Background Technology

[0002] Full-face excavation with triangular cross sections in medium-hard and hard rock strata requires the cutterhead device to have extremely high rigidity and strong rock-breaking ability.

[0003] Existing planetary excavation solutions for hard rock often have complex structures, such as multiple independently driven sub-cutterhead units. The complex transmission system and numerous moving parts pose challenges to the structural reliability, ease of maintenance, and manufacturing cost when subjected to the high impact and high load of hard rock excavation.

[0004] Therefore, there is an urgent need for a triangular roller cutter head device with a more compact and robust structure, a shorter transmission chain, and better adaptability to harsh working conditions in hard rock. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide a longitudinally mounted planetary cutterhead device for triangular cross-section excavation. It adopts a unique axially mounted longitudinal cutterhead body as the cutter carrier and drives the base movement through a set of efficient planetary mechanisms. The structure is highly integrated and has outstanding rigidity and strength. It is designed for efficient triangular excavation in hard rock strata.

[0006] To achieve the above objectives, the present invention provides a longitudinally positioned planetary roller cutter head device for triangular cross-section excavation, comprising: Base; The longitudinally positioned cutterhead body has its axis of rotation parallel to the intended tunneling direction and is rotatably supported on the base; A hobbing cutter is rotatably mounted on the outer peripheral surface of the longitudinally positioned cutter head body; A planetary transmission mechanism configured to drive the base to perform a compound planetary motion, the compound planetary motion including: driving the base to rotate about a fixed first axis; and driving the base to rotate about its own central axis. The circumferential motion and the rotational motion of the base are coupled to each other through the planetary transmission mechanism; The cutter head drive mechanism is used to drive the longitudinally placed cutter head body to rotate around its own axis; The rotational speed relationship between the base and its rotation is configured such that the cutting trajectory envelope of the longitudinal cutter head body and the hob mounted thereon forms a triangular cross-section.

[0007] By adopting this technical solution, the longitudinal cutterhead body is used as the single cutter bearing structure, and the base is driven by a planetary mechanism. The overall structure is extremely compact, with few moving parts and a short transmission chain. This highly integrated design brings excellent structural rigidity and impact resistance, making it very suitable for high-load conditions in hard rock formations and solving the problem of insufficient reliability of complex structures in hard rock.

[0008] Furthermore, the base maintains a preset proportional relationship between its rotation and eccentricity, and the rotation and eccentricity are in opposite directions.

[0009] By adopting this technical solution, the base's rotation and eccentricity are limited to a preset ratio and opposite directions, ensuring the precise motion relationship required to form the triangular excavation envelope.

[0010] Furthermore, the preset ratio is 2:1.

[0011] By adopting this technical solution and specifically limiting the ratio to 2:1, the core motion parameters for forming the triangular cross-section were established.

[0012] Furthermore, the planetary transmission mechanism is a differential planetary gear system, which includes a fixed gear ring and a planetary output gear connected to the base, wherein the ratio of the number of teeth of the fixed gear ring to the number of teeth of the planetary output gear is 3:2.

[0013] By adopting this technical solution, a 2:1 motion ratio is achieved through a differential planetary gear system with a gear ratio of 3:2. This solution has high transmission efficiency, compact structure, and large gear load capacity, and is a key specific implementation method for achieving the compact and robust design goals of this invention.

[0014] Furthermore, the cutter head drive mechanism is a built-in motor disposed between the longitudinally placed cutter head body and the base.

[0015] By adopting this technical solution, the built-in motor directly drives the longitudinal cutter head to rotate, which is a direct and efficient driving method that eliminates the need for a complex intermediate transmission mechanism, further simplifies the structure and improves reliability.

[0016] Furthermore, at least two rows of hobs are installed circumferentially along the longitudinal cutter head body; wherein the mounting axis of at least one row of hobs forms a preset, fixed acute angle with the generatrix direction of the longitudinal cutter head body.

[0017] By adopting this technical solution, multiple rows of cutters are arranged along the axial direction, and their mounting axis is set to form an acute angle with the generatrix of the cutter head body. This scientifically optimizes the force angle of the cutters, making them closer to vertically pressing into the rock, reducing harmful lateral forces, and improving rock breaking efficiency and cutter life.

[0018] Furthermore, the adjacent rows of roller cutters are staggered on the outer circumferential surface of the longitudinally positioned cutterhead body. By adopting this technical solution, the staggered arrangement of adjacent roller cutters increases the continuity of cutting coverage, improves the force distribution of the cutterhead body, and makes the rock-breaking process smoother with less vibration.

[0019] Furthermore, on the outer circumferential surface of the longitudinally placed cutter head body, a scraper is also installed between the hobs.

[0020] By adopting this technical solution, a scraper is added between the roller cutters, which enhances the cutter head's ability to pass through and adapt to complex rock formations such as the interface between soft and hard rocks or fault fracture zones, and can help clean up rock debris or cut soft interlayers.

[0021] Compared with the prior art, the present invention has the following advantages: The longitudinally positioned cutterhead body serves as the single hob support structure, and the base is driven by a planetary mechanism. The overall structure is extremely compact, with few moving parts and a short transmission chain. This highly integrated design brings excellent structural rigidity and impact resistance, making it very suitable for high-load conditions in hard rock formations and solving the problem of insufficient reliability of complex structures in hard rock. Attached Figure Description

[0022] Figure 1 This is a front view schematic diagram of the longitudinally mounted planetary roller cutter head device for triangular cross-section excavation in this invention after installation. Figure 2 This is a three-dimensional schematic diagram of the longitudinally mounted planetary roller cutter head device for triangular cross-section excavation in this invention after installation. Figure 3 This is a schematic diagram of the cutting trajectory envelope of the longitudinally positioned planetary hobbing cutter head device used for triangular cross-section excavation in this invention; Figure 4 This is a schematic diagram showing the operational status changes of the longitudinally positioned planetary cutterhead device used for triangular cross-section excavation in this invention.

[0023] Explanation of reference numerals in the attached diagram: 1. Base; 2. Vertical cutter head body; 3. Hob. Detailed Implementation

[0024] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0025] Please see the appendix Figure 1-3This invention provides a longitudinally mounted planetary roller cutterhead device for triangular cross-section excavation, aiming to solve the technical problem of requiring the cutterhead device to have both strong rock-breaking ability and extremely high structural rigidity when performing triangular full-section excavation in medium-hard to hard rock strata. To achieve this goal, a highly integrated innovative architecture is proposed: a base 1 responsible for performing specific planetary motion is directly coupled to a longitudinally mounted cutterhead body 2 that is axially longitudinal, can rotate independently at high speed, and is equipped with roller cutters 3. By combining the precise triangular motion trajectory provided by the base 1 with the high-speed rotation of the longitudinally mounted cutterhead body 2 itself, the roller cutters 3 can achieve efficient three-dimensional rolling crushing of the rock mass. The entire device is mounted on a robust base 1, which is rigidly connected to the main drive system of the tunnel boring machine via a flange or heavy-duty spline. This base 1 supports and drives the core working components. The key to achieving the triangular excavation trajectory lies in driving the base 1 to perform a specific compound planetary motion, a function achieved by a planetary transmission mechanism integrated into the drive chain.

[0026] This composite motion is specifically manifested as follows: the base 1 revolves around a fixed axis (first axis) that is offset from the center line of the shield tunnel, while simultaneously rotating around its own central axis. The two satisfy a strict ratio of 2 revolutions to 1 rotation, and the directions of rotation are opposite. This kinematic relationship is a necessary and sufficient condition for forming a triangular cutting envelope.

[0027] The preferred implementation of this compound motion is a differential planetary gear system with a specific gear ratio, which is configured as follows: Fixed gear ring: A large-diameter internal gear ring that is rigidly fixed to the front shield of the tunnel boring machine or the static support structure by means of a mounting base. During the operation of the cutterhead, this gear ring remains absolutely stationary and does not participate in rotation. Its number of teeth is denoted as Z2.

[0028] Planetary output gear (or eccentric gear): It meshes internally with the fixed gear ring mentioned above. The rotation center axis of this gear is parallel to but does not coincide with the center axis of the fixed gear ring. The vertical distance between the two is the eccentricity e. This parameter determines the specific shape of the triangular cross section formed. The output shaft of the planetary output gear is rigidly connected to the base 1 in this invention through an eccentric sleeve or planet carrier. Its number of teeth is denoted as Z1.

[0029] Power input and transmission: Power comes from the main drive motor of the tunnel boring machine, which drives the sun gear or planet carrier of the planetary gear system through the input shaft.

[0030] To achieve triangular section cutting, a specific motion relationship needs to be satisfied: while the base 1 revolves around the fixed axis 2 times, it rotates in the opposite direction 1 time around the central axis.

[0031] This kinematic relationship is guaranteed by gear parameters. When the gear ring is fixed, the ratio of the number of teeth Z,2 of the gear ring to the number of teeth Z1 of the planetary output gear must be 3:2 (i.e., Z2:Z1=3:2). For example, a specific engineering implementation is: Z2=51 teeth, Z1=34 teeth, because 51:34=3:2.

[0032] With this 3:2 gear ratio setting, when power is input, under the constraint of the fixed gear ring, the planetary output gear fixed to the base 1 will accurately generate a compound motion of 2 revolutions and 1 rotation in opposite directions. This motion relationship is guaranteed by the mechanical meshing rigidity of the gears, which is stable and reliable. The core working components include the longitudinally positioned cutter head body 2 and its independent drive: The core working component, which is rotatably supported above the base 1, is a longitudinally positioned cutter head body 2. The longitudinally positioned cutter head body 2 is an axially extending cylindrical or drum-shaped structure, which is mounted on the base 1 via a large, heavy-duty main bearing.

[0033] To ensure optimal working conditions for the hob 3, the longitudinal cutter head body 2 is driven by an independent cutter head drive mechanism (such as a built-in hydraulic motor or electric motor). This mechanism is located between the longitudinal cutter head body 2 and the base 1, and can independently drive the longitudinal cutter head body 2 to rotate at high speed and in a controllable manner around its own axis. This built-in direct drive method has a compact structure, a short transmission chain, and high reliability. Multiple cutters 3, serving as the main rock-breaking tools, are rotatably mounted on the outer cylindrical surface of the longitudinal cutterhead body 2. The cutters 3 are arranged in at least two rows along the axial direction of the longitudinal cutterhead body 2 to cover the excavation width.

[0034] To prevent the lateral cutter 3 from being damaged by excessive lateral force and to optimize its stress state, the lateral cutters 3 located on at least both sides of the longitudinal cutterhead body 2 have their mounting axes forming a preset, fixed acute angle α (e.g., 10° to 45°) with the generatrix direction of the cutterhead body 2. This angle α makes the direction of the pressing force of the lateral cutter 3 when cutting into the rock closer to the normal of the rock surface, thereby maximizing the crushing efficiency and minimizing the harmful lateral force.

[0035] To further improve cutting continuity, adjacent rows of hobs 3 can be staggered on the outer circumference of the longitudinal cutter head body 2, making the rock breaking process smoother.

[0036] On the outer circumferential surface of the longitudinally placed cutterhead body 2, scrapers can also be installed between the roller cutters 3 to treat soft rock interlayers, clean rock debris, and enhance formation adaptability.

[0037] In another preferred embodiment, a tearing cutter can also be installed between the roller cutters 3 on the outer peripheral surface of the longitudinal cutterhead body 2, but it is not limited to the scraper and tearing cutter described, but can also be common tunneling cutters such as shell cutters. Workflow: Please refer to the appendix Figure 4 When the tunnel boring machine advances, the main drive system drives the base 1 to perform a strict 2:1 planetary rotation-rotation compound planetary motion through the planetary transmission mechanism (3:2 gear ratio system), providing a triangular spatial motion trajectory for the entire device.

[0038] At the same time, the built-in cutter head drive mechanism is activated, driving the longitudinal cutter head body 2 to rotate at high speed around its own axis.

[0039] The motion of the roller cutter 3 mounted on the rotating longitudinal cutter head body 2 is a combination of the two motions mentioned above. The planetary motion of the base 1 causes the roller cutter 3 to move along a triangular trajectory, while the high-speed rotation of the longitudinal cutter head body 2 gives the roller cutter 3 an extremely high rotational linear speed. The combination of the two causes the roller cutter 3 to roll at high speed while moving, and periodically roll the rock vertically at an optimized angle, thereby achieving efficient and continuous crushing of the rock mass within the triangular cross section.

[0040] As the tunnel boring machine continues to advance, the above process is repeated, thereby achieving continuous, efficient, and full-face excavation of triangular tunnels in hard rock strata. The present invention has been described in detail above with reference to the accompanying drawings and embodiments. Those skilled in the art can make various modifications to the present invention based on the above description. Therefore, certain details in the embodiments should not be construed as limiting the present invention, and the scope of protection of the present invention shall be defined by the appended claims.

Claims

1. A longitudinally positioned planetary roller cutter head device for triangular cross-section excavation, characterized in that, include: Base; The longitudinally positioned cutterhead body has its axis of rotation parallel to the intended tunneling direction and is rotatably supported on the base; A hobbing cutter is rotatably mounted on the outer peripheral surface of the longitudinally positioned cutter head body; A planetary transmission mechanism configured to drive the base to perform a compound planetary motion, the compound planetary motion including: driving the base to rotate about a fixed first axis; and driving the base to rotate about its own central axis. The circumferential motion and the rotational motion of the base are coupled to each other through the planetary transmission mechanism; The cutter head drive mechanism is used to drive the longitudinally placed cutter head body to rotate around its own axis; The rotational speed relationship between the base and its rotation is configured such that the cutting trajectory envelope of the longitudinal cutter head body and the hob mounted thereon forms a triangular cross-section.

2. The longitudinally positioned planetary roller cutter head device for triangular cross-section excavation according to claim 1, characterized in that: The base maintains a preset proportional relationship between its rotation and circumference, and the rotation and circumference are in opposite directions.

3. The longitudinally positioned planetary roller cutter head device for triangular cross-section excavation according to claim 2, characterized in that: The preset ratio is 2:

1.

4. The longitudinally positioned planetary roller cutter head device for triangular cross-section excavation according to claim 3, characterized in that: The planetary transmission mechanism is a differential planetary gear system, which includes a fixed gear ring and a planetary output gear connected to the base. The ratio of the number of teeth on the fixed gear ring to the number of teeth on the planetary output gear is 3:

2.

5. The longitudinally positioned planetary roller cutter head device for triangular cross-section excavation according to claim 1, characterized in that: The cutter head drive mechanism is a built-in motor located between the vertically placed cutter head body and the base.

6. The longitudinally positioned planetary roller cutter head device for triangular cross-section excavation according to claim 1, characterized in that: At least two rows of hobs are mounted circumferentially along the longitudinal cutter head body; wherein the mounting axis of at least one row of hobs forms a preset, fixed acute angle with the generatrix direction of the longitudinal cutter head body.

7. The longitudinally positioned planetary roller cutter head device for triangular cross-section excavation according to claim 6, characterized in that: The two adjacent rows of hobs are staggered on the outer circumferential surface of the longitudinal cutter head body.

8. The longitudinally positioned planetary roller cutter head device for triangular cross-section excavation according to claim 1, characterized in that: A scraper is also installed between the hobs on the outer circumferential surface of the longitudinally placed cutter head body.

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