Shaft driving cutting tooth structure and anti-wear method

Abstract

The application relates to a vertical shaft tunneling cutting tooth structure and a wear prevention method, and specifically discloses a cutting tooth structure for vertical shaft tunneling, which comprises a connecting arm, an end face sealing plate, a horizontal tunneling cylinder, a tunneling cutter, a central support cylinder, a pre-tightening force adjusting mechanism, an arc limiting mechanism, an overpressure overflow valve mechanism and a backflow reset mechanism; the horizontal tunneling cylinder is arranged between the two end face sealing plates, the central support cylinder is coaxially arranged in the horizontal tunneling cylinder and connected to the connecting arm; two groups of tunneling cutters are arranged in a spiral shape on the outer circumferential surface of the horizontal tunneling cylinder, the tunneling cutter comprises a cutter seat which can be telescopically and rotatably arranged and a cutter head which is arranged at the outer end of the cutter seat in an inclined manner; the arc limiting mechanism is arranged on the inner wall of the horizontal tunneling cylinder and connected to the cutter seat, the overpressure overflow valve mechanism abuts against the arc limiting mechanism, and the backflow reset mechanism is connected to the overpressure overflow valve mechanism. The rigid cutter head structure can simultaneously consider normal tunneling efficiency and cutter head protection effect under abnormal hard impact working conditions.

Description

Technical Field

[0001] This invention relates to the field of tunneling machine technology, specifically to a cutting tooth structure and wear prevention method for vertical shaft tunneling. Background Technology

[0002] Shaft excavation equipment typically needs to continuously break up rock, soil, and interbedded blocks within a limited shaft space. Its cutterhead mechanism must possess sufficient cutting power and withstand the periodically varying impact loads during excavation. Existing shaft excavators often employ fixed cutterheads or rigidly mounted cutter heads, which rotate with the cutterhead and contact the rock mass in a relatively fixed posture. When the excavated object is ordinary rock with relatively uniform hardness, this type of structure can complete conventional breaking operations. However, during shaft excavation, the strata ahead often contain boulders, high-strength rock blocks, hard interbedded layers, or locally protruding hard obstacles. When the cutter head rotates into the working side, it may suddenly experience concentrated impacts far exceeding normal excavation resistance.

[0003] For rigid cutterheads, the aforementioned concentrated impacts typically act directly on the cutterhead tip or a localized area of ​​the cutting edge. The cutterhead lacks space for controlled retreat along the force direction and also lacks the structural conditions to transform a single positive impact into multi-directional disturbance and fracturing. If the cutterhead depth or propulsion pressure is increased to improve rock-breaking capability, the cutterhead is more prone to chipping, uneven wear, breakage, or loosening at the cutterhead joint when encountering high-strength hard points. Conversely, if the depth or propulsion load is reduced to protect the cutterhead, the tunneling efficiency in ordinary rock formations will significantly decrease. Therefore, existing rigid cutterhead structures cannot simultaneously achieve both normal tunneling efficiency and cutterhead protection under abnormally hard impact conditions. Summary of the Invention

[0004] This application provides a cutting tooth structure and wear prevention method for vertical shaft excavation. The main purpose is to achieve a rigid cutterhead structure that simultaneously ensures normal excavation efficiency and cutter head protection under abnormal hard impact conditions.

[0005] To achieve the above objectives, a first aspect of the present application provides a cutting-type cutting tooth structure for vertical shaft excavation, including a connecting arm, an end face sealing plate, a horizontal excavation cylinder, excavation cutters, a central support cylinder, a preload adjustment mechanism, an arc limit mechanism, an overpressure relief valve mechanism, and a return flow reset mechanism. The horizontal tunneling cylinder is disposed between the two end face sealing plates, and the central support cylinder is coaxially disposed inside the horizontal tunneling cylinder and connected to the power output end of the connecting arm; The two sets of tunneling cutters are spirally arranged on the outer circumference of the horizontal tunneling cylinder. The tunneling cutters include a telescopic and rotatable cutter holder and a cutter head inclined at the outer end of the cutter holder. The arc-limiting mechanism is disposed on the inner wall of the horizontal tunneling cylinder and connected to the cutterhead. The overpressure relief valve mechanism abuts against the arc-limiting mechanism. The reflux reset mechanism is connected to the overpressure relief valve mechanism. The preload adjustment mechanism is disposed in the central support cylinder and abuts against the preload push rod of the overpressure relief valve mechanism.

[0006] In one feasible embodiment, the tunneling cutter further includes a sealing ring, which is fixedly disposed on the outer wall of the horizontal tunneling cylinder. The cutter holder is telescopically and rotatably disposed within the sealing ring. The cutter head is detachably connected to the outer end of the cutter holder, and the cutter head is inclined toward the area where the end face sealing plate is located.

[0007] In one feasible implementation, the arc-shaped limiting mechanism includes an arc-shaped limiting plate, a limiting contact rail, a rotating connecting seat, a connecting shaft, and rollers. The arc-shaped limiting plate is fixedly disposed on the inner wall of the horizontal tunneling cylinder, the limiting contact rail is disposed on the arc-shaped inner wall of the arc-shaped limiting plate, the outer end of the connecting shaft is fixedly connected to the cutter holder, the rotating connecting seat is fixedly connected to the inner end of the connecting shaft, and at least two rollers are disposed on the rotating connecting seat and roll against the inner side of the limiting contact rail.

[0008] In one feasible implementation, the limiting contact track is an arc-shaped closed-loop ring adapted to the curvature of the inner wall of the horizontal tunneling cylinder. The limiting contact track has an arc-shaped high point interval for at least two of the rollers to abut. The rotating connecting seat forms a combined constraint structure of rotation and radial extension with the limiting contact track through the rollers.

[0009] In one feasible embodiment, the overpressure relief valve mechanism includes a first telescopic rod, an overflow port, a return port, and a pre-tightening force push rod. The outer end of the first telescopic rod is rotatably supported on the inner end face of the rotating connecting seat by a bearing. The inner cavity of the overpressure relief valve mechanism stores incompressible fluid. The overflow port and the return port are respectively disposed on the outer wall of the cavity of the overpressure relief valve mechanism. The pre-tightening force push rod is pressed against the sealing element disposed in the overflow port channel by an elastic element.

[0010] In one feasible embodiment, the reflux reset mechanism includes a reflux drive cylinder, a second telescopic rod, a sealing piston, a hydraulic medium storage chamber, and a high-pressure gas chamber. The reflux drive cylinder is fixed on the outer wall of the overpressure relief valve mechanism. The sealing piston is movably disposed within the reflux drive cylinder. The hydraulic medium storage chamber is located on the side of the sealing piston near the overflow port and the reflux port. The high-pressure gas chamber is located on the other side of the sealing piston. The second telescopic rod is disposed within the high-pressure gas chamber and supports the sealing piston. One-way valves are respectively provided at the junctions of the overflow port and the reflux port with the hydraulic medium storage chamber.

[0011] In one feasible embodiment, an overflow valve mounting seat is fixedly provided on the outer wall of the central support cylinder, and a plurality of overpressure overflow valve mechanisms are respectively fixedly provided on the corresponding overflow valve mounting seats. A plurality of pre-tightening push rods pass through the central support cylinder and the overflow valve mounting seat and extend into the inner cavity of the central support cylinder.

[0012] In one feasible embodiment, the preload adjustment mechanism includes a moving shaft, an inclined drive seat, an internal thread drive cylinder, a worm gear, a worm, and a polygonal limiting seat. The moving shaft is disposed in the middle of the inner cavity of the central support cylinder. A plurality of inclined drive seats are disposed on the outer circumferential surface of the moving shaft. The inner end of each preload push rod slides against the inclined outer wall of the corresponding inclined drive seat. The internal thread drive cylinder is screwed to the outer side of one end of the moving shaft and rotatably limited within the central support cylinder. The worm gear is fixedly disposed on the outer wall of the internal thread drive cylinder. The worm is disposed at the end of the central support cylinder and meshes with the worm gear. The other end of the moving shaft has a polygonal outer contour. The polygonal limiting seat is fixedly disposed on the inner wall of the central support cylinder and slides in cooperation with the polygonal outer contour of the moving shaft.

[0013] In one feasible implementation, a spiral guide plate is provided next to each group of tunneling cutters. The spiral guide plate is fixedly installed on the outer wall of the horizontal tunneling cylinder, and the spiral direction of the spiral guide plate is consistent with the spiral arrangement direction of the tunneling cutters in the corresponding group. Multiple reinforcing ribs are provided between the end face sealing plate and the edge of the horizontal tunneling cylinder.

[0014] In a second aspect, this application also provides a method for preventing wear on a cutting-type cutting tooth structure used in vertical shaft excavation, employing the cutting-type cutting tooth structure as described in the first aspect, comprising the following steps: The power output end of the connecting arm drives the central support cylinder and the horizontal tunneling cylinder coaxially arranged with the central support cylinder to rotate, so that the two sets of tunneling cutters arranged in a spiral on the outer circumference of the horizontal tunneling cylinder can tunnel the area in front of the shaft. The cutting head of the tunneling cutter participates in the tunneling along with the cutter holder. The cutting head contacts the rock mass in an inclined posture. The cutter holder has extension and rotation margins relative to the horizontal tunneling cylinder under the constraint of the arc limiting mechanism. When the tunneling resistance experienced by the cutter head is transmitted to the cutter holder and the arc-limiting mechanism, the arc-limiting mechanism transmits the force to the overpressure relief valve mechanism, and the overpressure relief valve mechanism constrains the position of the cutter holder under the overflow opening pressure limited by the preload rod. When the overpressure relief valve mechanism overflows, the tool holder extends and deflects relative to the arc limiting mechanism. The return reset mechanism is connected to the overpressure relief valve mechanism and returns to it, so that the tool holder and the tool head are reset.

[0015] This application provides a cutting tooth structure and wear prevention method for vertical shaft excavation. By setting excavation tools arranged in a spiral pattern on the outer periphery of a horizontal excavation cylinder, and forming a motion structure chain with the tool holder, inclined cutter head, arc limiting mechanism, overpressure relief valve mechanism, return reset mechanism, and preload adjustment mechanism, the cutting tooth structure can maintain stable outward extension and continuous cutting in ordinary rock formations. When encountering boulders, high-strength rock blocks, or local hard obstacles, the tool holder can be controlled to deflect and slightly retract radially through the cooperation of the arc-shaped closed-loop track and rollers, thereby reducing the instantaneous large bite impact of the cutter head on hard points and reducing the chipping, breakage, and abnormal wear of the cutter head. The overpressure relief valve mechanism limits the relief opening pressure with a pre-tightening push rod, ensuring that the cutter head only retracts when the set impact threshold is exceeded, thus preventing premature deflection during normal tunneling and reducing rock-breaking efficiency. The return reset mechanism completes the return of hydraulic medium through the hydraulic medium storage chamber and the high-pressure gas chamber, allowing the cutter head to automatically return to its working position after leaving the high-impact area, ensuring the continuity of subsequent tunneling cycles and the consistency of cutter head posture. The pre-tightening adjustment mechanism acts synchronously on multiple pre-tightening push rods through a moving shaft, inclined drive seat, worm gear, and polygonal limit seat, which can centrally adjust the retraction threshold of multiple cutter heads according to different formation hardness, improving the adaptability of the whole machine to complex vertical shaft formations.

[0016] Compared with simple rigid cutter heads or ordinary elastic buffer cutter holders, this invention can not only protect the cutter head, but also improve the stress mode of hard rock mass by using the composite contact state formed by the inclined cutter head and controlled deflection. This causes the hard points to be disturbed in the circumferential, axial and radial directions, which is conducive to improving the crushing efficiency of hard rock blocks. It also improves the reliability, continuous operation capability and maintenance economy of the shaft boring machine with minimal changes to the main structure of the horizontal cylindrical cutterhead. Attached Figure Description

[0017] Figure 1 This illustration shows a schematic diagram of the cutting-type cutting tooth structure for vertical shaft excavation provided in an embodiment of this application; Figure 2 This paper shows a side view of the single tunneling tool and horizontal tunneling cylinder provided in an embodiment of this application. Figure 3 A three-dimensional structural schematic diagram of the single tunneling tool and horizontal tunneling cylinder provided in the embodiments of this application is shown; Figure 4 This paper shows a schematic diagram illustrating the positions of the central support cylinder, the arc limiting mechanism, and the reflux reset mechanism provided in an embodiment of this application. Figure 5 A schematic diagram of the structure of the moving shaft provided in an embodiment of this application is shown; Figure 6 This paper shows a schematic diagram illustrating the positions of the central support cylinder and the preload adjustment mechanism provided in an embodiment of this application. Figure 7 A schematic diagram of the polygonal limiting seat provided in an embodiment of this application is shown; Figure 8 A schematic diagram of the worm gear and worm provided in an embodiment of this application is shown; Figure 9 A schematic diagram of the limiting contact track provided in an embodiment of this application is shown; Figure 10 A schematic diagram of the connecting shaft provided in an embodiment of this application is shown; Figure 11 A schematic diagram of the preload rod provided in an embodiment of this application is shown; Figure 12 A schematic diagram of the reflux reset mechanism provided in an embodiment of this application is shown.

[0018] In the diagram: 10. Connecting arm; 20. End face sealing plate; 30. Horizontal tunneling barrel; 40. Tunneling cutter; 50. Central support cylinder; 60. Preload adjustment mechanism; 70. Arc limit mechanism; 80. Overpressure relief valve mechanism; 90. Return reset mechanism; 21. Reinforcing rib; 31. Spiral guide plate; 41. Cutter holder; 42. Cutter head; 43. Sealing ring; 51. Relief valve mounting seat; 61. Moving shaft; 62. Inclined drive seat; 63. 64. Internal thread drive cylinder, 65. Worm gear, 66. Worm, 77. Polygonal limit seat, 78. Arc-shaped limit plate, 79. Limit contact rail, 70. Rotary connecting seat, 71. Connecting shaft, 72. Roller, 83. First telescopic rod, 84. Overflow port, 85. Return port, 86. Pre-tightening force push rod, 97. Return drive cylinder, 98. Second telescopic rod, 99. Sealed piston, 90. Hydraulic medium storage chamber, 91. High-pressure gas chamber. Detailed Implementation

[0019] To better understand the technical solutions provided in the embodiments of this specification, the technical solutions of the embodiments of this specification will be described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the embodiments of this specification and the specific features in the embodiments are detailed descriptions of the technical solutions of the embodiments of this specification, rather than limitations on the technical solutions of this specification. In the absence of conflict, the embodiments of this specification and the technical features in the embodiments can be combined with each other.

[0020] In this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, without necessarily requiring or implying any such actual relationship or order between these entities or operations. Furthermore, the terms "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 a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element. The term "two or more" includes two or more cases.

[0021] This invention provides a cutting-type cutting tooth structure for vertical shaft excavation. This cutting-type cutting tooth structure is installed at the excavation end of a vertical shaft excavator. A horizontal excavation cylinder 30 drives multiple sets of excavating cutters 40 to rotate around their own axis, thereby breaking up and excavating the rock mass, soil layer, or strata containing hard blocks on the front side of the shaft. This invention enables the cutter head 42, cutter holder 41, arc-limiting mechanism 70, overpressure overflow valve mechanism 80, return flow reset mechanism 90, and preload adjustment mechanism 60 to form a system that maintains stability under normal excavation loads and allows the cutter head 42 to undergo controlled retraction and automatic reset under high impact loads, thus balancing excavation efficiency, cutter head 42 damage resistance, and complex rock breaking capability.

[0022] Please see Figures 1 to 12As shown, in some embodiments, the cutting-type cutting tooth structure includes a connecting arm 10, end face sealing plates 20, a horizontal tunneling cylinder 30, a tunneling cutter 40, a central support cylinder 50, a preload adjustment mechanism 60, an arc limiting mechanism 70, an overpressure relief valve mechanism 80, and a return flow reset mechanism 90. The connecting arm 10 is used to connect to the main propulsion device or power output end of the shaft tunneling machine. The two end face sealing plates 20 are respectively disposed at both ends of the horizontal tunneling cylinder 30, which is located between the two end face sealing plates 20. The central support cylinder 50 is coaxially disposed inside the horizontal tunneling cylinder 30. The two ends of the central support cylinder 50 can be fixed to the power output end of the connecting arm 10 through an end connection structure, a flange structure, or a key connection structure, so that the torque output by the power output end can be transmitted to the horizontal tunneling cylinder 30 through the central support cylinder 50, thereby driving the horizontal tunneling cylinder 30 and the tunneling cutter 40 disposed on its outer circumference to rotate synchronously.

[0023] Specifically, the horizontal tunneling casing 30 can be a hollow cylindrical metal cylinder, with its outer circumference serving as the mounting base for the tunneling cutter 40, and its inner cavity serving as the space for the arc-limiting mechanism 70, the overpressure relief valve mechanism 80, and the central support cylinder 50. Two end-face sealing plates 20 are located inside the ends of the horizontal tunneling casing 30, serving to close or reinforce the end structure of the horizontal tunneling casing 30 and provide stable support for the force transmission between the horizontal tunneling casing 30 and the connecting arm 10. Multiple reinforcing ribs 21 are provided between the end-face sealing plates 20 and the edges of the horizontal tunneling casing 30, spaced circumferentially along the horizontal tunneling casing 30, preventing local deformation or torsional instability at the ends of the horizontal tunneling casing 30 when subjected to tunneling resistance and periodic impact loads.

[0024] like Figure 1 As shown, in some embodiments, two sets of tunneling cutters 40 are disposed on the outer circumferential surface of the horizontal tunneling cylinder 30, with each set of cutters 40 arranged in a spiral shape from the edge to the center of the horizontal tunneling cylinder 30. The two sets of cutters 40 can correspond to the left and right sides of the horizontal tunneling cylinder 30 respectively, or they can be distributed in opposite or unidirectional spirals along the axial direction of the horizontal tunneling cylinder 30. Through this spiral arrangement, when the horizontal tunneling cylinder 30 rotates, the cutter heads 42 at different axial positions can enter the tunneling contact area sequentially, avoiding multiple cutter heads 42 from being concentrated under the same impact at the same instant, which is beneficial for dispersing the tunneling load and subjecting the rock mass in front of the shaft to gradually changing cutting, squeezing, and crushing effects along the circumferential and axial directions.

[0025] Specifically, each set of tunneling cutters 40 is equipped with a corresponding spiral guide plate 31. The spiral guide plate 31 is fixed to the outer wall of the horizontal tunneling cylinder 30, and its spiral direction is consistent with the spiral arrangement direction of the corresponding set of tunneling cutters 40. The spiral guide plate 31 can guide the broken rock blocks, soil or particles during the tunneling process, so that the broken material is disturbed and discharged along the spiral direction of the outer periphery of the horizontal tunneling cylinder 30, reducing the probability of debris accumulating between adjacent cutter heads 42, thereby reducing the additional wear caused by the cutter heads 42 repeatedly crushing debris.

[0026] like Figure 4 , Figure 9 and Figure 10 As shown, in some embodiments, the tunneling cutter 40 includes a cutter holder 41, a cutter head 42, and a sealing ring 43. The sealing ring 43 is fixedly mounted on the outer wall of the horizontal tunneling cylinder 30, and an installation channel for the cutter holder 41 to pass through is formed inside the sealing ring 43. The cutter holder 41 is telescopically and rotatably mounted inside the sealing ring 43, and the cutter head 42 is detachably connected to the outer end of the cutter holder 41. The cutter head 42 and the cutter holder 41 can be connected by a threaded connection, a snap-fit ​​connection, a pressure plate locking connection, or a pin limiting connection, so that the cutter head 42 can be disassembled and replaced separately after wear, without the need to replace the entire cutter holder 41 and the internal limiting structure. The sealing ring 43 provides external guidance for the cutter holder 41 and reduces the entry of mud, sand, gravel, and fine rock cuttings into the interior of the horizontal tunneling cylinder 30, protecting the internal curvature limiting mechanism 70 and the overpressure relief valve mechanism 80.

[0027] Specifically, the cutter head 42 is inclined relative to the cutter holder 41, with the inclination direction of the cutter head 42 facing the area where the end face sealing plate 20 is located. This inclined posture ensures that when the cutter head 42 enters the tunneling contact area with the horizontal tunneling cylinder 30, it does not act on the hard rock mass in a completely positive rigid top pressure manner, but rather contacts the rock mass with a lateral force component. Under normal tunneling load, the cutter holder 41 is constrained by the arc-limiting mechanism 70 and the overpressure relief valve mechanism 80 to maintain a stable working position, and the cutter head 42 can maintain sufficient cutting ability. When encountering high-strength rock blocks or protruding hard obstacles, the impact load on the cutter head 42 is transmitted through the cutter holder 41 to the arc-limiting mechanism 70 and the overpressure relief valve mechanism 80, so that the cutter holder 41 obtains controlled extension and deflection margins, preventing the cutter head 42 from forcibly biting into hard points in a single facing direction.

[0028] like Figure 9 and Figure 10As shown, in some embodiments, the arc-shaped limiting mechanism 70 is disposed on the inner wall of the horizontal tunneling cylinder 30 and corresponds one-to-one with the tunneling cutter 40. The arc-shaped limiting mechanism 70 includes an arc-shaped limiting plate 71, a limiting contact rail 72, a rotating connecting seat 73, a connecting shaft 74, and rollers 75. The arc-shaped limiting plate 71 is fixedly disposed on the inner wall of the inner cavity of the horizontal tunneling cylinder 30, and the shape of the inner wall of the arc-shaped limiting plate 71 is the same as the arc of the inner wall of the horizontal tunneling cylinder 30. The limiting contact rail 72 is disposed on the arc-shaped inner wall of the arc-shaped limiting plate 71. The outer end of the connecting shaft 74 is fixedly connected to the cutter holder 41, and the inner end of the connecting shaft 74 is fixedly connected to the rotating connecting seat 73. At least two rollers 75 are disposed on the rotating connecting seat 73, and the rollers 75 roll against the inner side of the limiting contact rail 72.

[0029] Specifically, the limiting contact track 72 is an arc-shaped closed loop with arc-shaped high point sections for at least two rollers 75 to abut against. When the cutterhead 41 is in the normal tunneling working position, at least two rollers 75 abut against the corresponding high point areas of the limiting contact track 72, keeping the rotating connecting seat 73, connecting shaft 74, cutterhead 41, and cutter head 42 in a stable, extended, and inclined position. Because the rollers 75 and the limiting contact track 72 have rolling contact, the cutterhead 41 can deflect in a controlled manner along the limiting contact track 72 when subjected to impact loads, avoiding the problems of jamming, chipping, or excessively rapid local wear that are common in ordinary chute structures.

[0030] like Figure 9 and Figure 10 As shown, in some embodiments, the limiting contact track 72 does not simply restrict the rotation of the cutter head 41, but together with the roller 75, forms a composite constraint structure of rotation and radial extension. When the cutter head 42 is impacted by high-strength hard rock, the cutter head 41 drives the rotating connecting seat 73 to deflect via the connecting shaft 74. The roller 75 rolls along the limiting contact track 72. The arc change of the limiting contact track 72 causes the rotating connecting seat 73 to generate radial displacement while deflecting, thereby causing the cutter head 41 to contract slightly relative to the horizontal tunneling cylinder 30. This slight contraction reduces the instantaneous bite depth of the cutter head 42 into the hard rock, while the deflection changes the contact direction between the cutter head 42 and the hard point, transforming the impact load originally concentrated in front of the cutter head 42 into a composite load with axial and tangential components. This is beneficial for increasing the probability of hard rock fragmentation and reducing the risk of chipping, breakage, and abnormal wear of the cutter head 42.

[0031] like Figure 11As shown, in some embodiments, the overpressure relief valve mechanism 80 is disposed outside the central support cylinder 50 and abuts against the arc-limiting mechanism 70. The overpressure relief valve mechanism 80 includes a first telescopic rod 81, an overflow port 82, a return port 83, and a pre-tightening force rod 84. The outer end of the first telescopic rod 81 is rotatably supported on the inner end face of the rotating connecting seat 73 by a bearing, so that the rotating connecting seat 73 will not generate rigid torsional interference with the first telescopic rod 81 when it deflects. The inner cavity of the overpressure relief valve mechanism 80 stores incompressible fluid. The overflow port 82 and the return port 83 are respectively disposed on the outer wall of the cavity of the overpressure relief valve mechanism 80. The pre-tightening force rod 84 is pressed against the sealing element disposed in the overflow port 82 channel. The sealing element may be a valve core, a steel ball, a cone valve, or a plunger structure. The pre-tightening force rod 84 applies sealing pressure to the sealing element through an elastic element or a pressing structure.

[0032] Specifically, under normal rock formations or normal tunneling resistance, since the elastic element tightened by the pre-tightening rod 84 is already in a pre-tightened state, overcoming the deformation requires pressure exceeding a threshold. The pressure on the first telescopic rod 81 is insufficient to allow the fluid in the cavity of the overpressure relief valve mechanism 80 to be discharged through the overflow port 82. The first telescopic rod 81 maintains support for the rotating connecting seat 73, and the cutter holder 41 and cutter head 42 maintain their normal working positions. When the cutter head 42 encounters high-strength rock blocks, boulders, or other high-hardness obstacles, and the impact load is transmitted to the first telescopic rod 81 through the cutter holder 41, connecting shaft 74, and rotating connecting seat 73, the first telescopic rod 81 applies pressure to the cavity of the overpressure relief valve mechanism 80. If this pressure exceeds the sealing pressure formed by the pre-tightening rod 84 on the sealing element, the sealing element retracts, and the incompressible fluid in the cavity enters the return reset mechanism 90 through the overflow port 82. The first telescopic rod 81 is allowed to retract accordingly, and the cutter holder 41 completes controlled contraction and deflection under the constraint of the limiting contact track 72.

[0033] like Figure 11 and Figure 12As shown, in some embodiments, the reflux reset mechanism 90 is fixed to the outer wall of the overpressure relief valve mechanism 80 and is connected to the overflow port 82 and the reflux port 83 of the overpressure relief valve mechanism 80, respectively. The reflux reset mechanism 90 includes a reflux drive cylinder 91, a second telescopic rod 92, a sealing piston 93, a hydraulic medium storage chamber 94, and a high-pressure gas chamber 95. The sealing piston 93 is movably disposed within the reflux drive cylinder 91. The hydraulic medium storage chamber 94 is located on the side of the sealing piston 93 closest to the overflow port 82 and the reflux port 83, and the high-pressure gas chamber 95 is located on the other side of the sealing piston 93. The high-pressure gas chamber 95 can be filled with nitrogen or other stable inert gases. The second telescopic rod 92 is disposed within the high-pressure gas chamber 95 and supports the sealing piston 93, so that the sealing piston 93 remains axially stable during reciprocating movement. One-way valves are respectively installed at the connection points of overflow port 82 and return port 83 with hydraulic medium storage chamber 94, so that hydraulic medium can flow in the direction of overflow and return, avoiding crosstalk between the two flow paths.

[0034] Specifically, when the overpressure relief valve mechanism 80 overflows, the hydraulic medium enters the hydraulic medium storage chamber 94 through the overflow port 82, pushing the sealing piston 93 to move towards the high-pressure gas chamber 95 and compressing the gas in the high-pressure gas chamber 95. At this time, the cutter head 41 has already retreated under the constraint of the arc limit mechanism 70, and the contact posture between the cutter head 42 and the hard rock mass changes, reducing the instantaneous impact peak of the cutter head 42. As the horizontal tunneling cylinder 30 continues to rotate, after the impacted cutter head 42 leaves the main stress area or the hard point is broken, the external resistance to the cutter head 42 decreases, and the gas pressure in the high-pressure gas chamber 95 pushes the sealing piston 93 to move in the opposite direction. The hydraulic medium flows back to the inner cavity of the overpressure relief valve mechanism 80 through the return port 83, the second telescopic rod 92 extends outward again, and the rotating connecting seat 73, connecting shaft 74, cutter head 41, and cutter head 42 return to the normal tunneling position under the cooperation of the limit contact rail 72 and the roller 75.

[0035] like Figure 6 , Figure 8 , Figure 9 , Figure 10 As shown, in some embodiments, an overflow valve mounting seat 51 is fixedly installed on the outer wall of the central support cylinder 50, and multiple overpressure overflow valve mechanisms 80 are respectively fixedly installed on the corresponding overflow valve mounting seat 51. The overflow valve mounting seat 51 can adopt a seat structure arranged in a circumferential interval, with one end fixed to the outer wall of the central support cylinder 50 and the other end supporting the corresponding overpressure overflow valve mechanism 80. Multiple preload rods 84 pass through the central support cylinder 50 and the overflow valve mounting seat 51 respectively and extend into the inner cavity of the central support cylinder 50, so that the preload adjustment mechanism 60 can uniformly act on multiple preload rods 84 inside the central support cylinder 50. This arrangement avoids setting an adjustment component separately for each cutterhead 41 outside the horizontal tunneling cylinder 30, which can reduce the risk of exposed adjustment structures being damaged by mud, rock cuttings and impact.

[0036] like Figure 8 As shown, in some embodiments, the preload adjustment mechanism 60 includes a moving shaft 61, an inclined drive seat 62, an internal thread drive cylinder 63, a worm gear 64, a worm 65, and a polygonal limiting seat 66. The moving shaft 61 is disposed in the middle of the inner cavity of the central support cylinder 50. Multiple inclined drive seats 62 are disposed on the outer circumferential surface of the moving shaft 61, and the inner ends of each preload push rod 84 slide against the inclined outer wall of the corresponding inclined drive seat 62. The internal thread drive cylinder 63 is screwed to the outer side of one end of the moving shaft 61 and is rotatably limited within the central support cylinder 50. The worm gear 64 is fixed to the outer wall of the internal thread drive cylinder 63, and the worm 65 is disposed at the end of the central support cylinder 50 and meshes with the worm gear 64. The other end of the moving shaft 61 has a polygonal outer contour. The polygonal limiting seat 66 is fixedly disposed on the inner wall of the central support cylinder 50 and slides in cooperation with the polygonal outer contour of the moving shaft 61, so that the moving shaft 61 cannot rotate with the internal thread drive cylinder 63, but can only move axially along the central support cylinder 50.

[0037] Specifically, before construction or after changing the stratum, workers can rotate the worm gear 65 using a tool. The worm gear 65 drives the worm wheel 64 and the internal thread drive cylinder 63 to rotate. The internal thread drive cylinder 63, through threaded engagement, pushes the moving shaft 61 to move slightly axially. When the moving shaft 61 moves, the contact positions of multiple inclined drive seats 62 and multiple pre-tightening rods 84 change synchronously. The inclined outer wall of the inclined drive seat 62 pushes the corresponding pre-tightening rod 84 to produce a slight radial displacement, thereby simultaneously changing the overflow opening pressure of multiple overpressure relief valve mechanisms 80. When the stratum hardness is low or mainly composed of ordinary soil and rock, the overflow opening pressure can be appropriately reduced to allow the cutter head 42 to retract in time when encountering abnormally hard points. When the overall stratum hardness is high but the impact distribution is relatively uniform, the overflow opening pressure can be appropriately increased to maintain a strong tunneling capacity for the cutter head 42 and avoid premature retraction that would lead to a decrease in tunneling efficiency.

[0038] In some embodiments, the tunneling process of the present invention is as follows: the power output end of the connecting arm 10 drives the central support cylinder 50 and the horizontal tunneling cylinder 30 coaxially arranged with the central support cylinder 50 to rotate. The horizontal tunneling cylinder 30 drives two sets of spirally arranged tunneling cutters 40 to enter the tunneling area in front of the shaft in sequence. The cutter head 42 participates in tunneling along with the cutter holder 41. The cutter head 42 contacts the rock mass in an inclined posture. The cutter holder 41 is kept in a telescopic and rotatable installation state in the sealing ring 43, and its initial working position is defined by the arc limit mechanism 70 and the overpressure relief valve mechanism 80. During normal tunneling, the overpressure relief valve mechanism 80 remains blocked, the first telescopic rod 81 supports the rotating connecting seat 73, the roller 75 abuts against the arc-shaped high point area of ​​the limiting contact track 72, and the cutter head 42 cuts the rock mass in a stable extended state.

[0039] Specifically, when a cutter head 42 encounters a high-strength rock block while rotating into the working side, the resistance experienced by the cutter head 42 is transmitted to the limiting contact track 72 via the cutter holder 41, connecting shaft 74, rotating connecting seat 73, and roller 75. Simultaneously, the rotating connecting seat 73 applies pressure to the first telescopic rod 81. When the pressure does not reach the overflow opening pressure, the cutter holder 41 maintains its original working posture to ensure continuous cutting of ordinary rock. When the pressure reaches or exceeds the overflow opening pressure, the overpressure overflow valve mechanism 80 overflows, the first telescopic rod 81 begins to retract, the roller 75 rolls along the limiting contact track 72, and the cutter holder 41 deflects while undergoing a slight radial contraction. Since the cutter head 42 is originally inclined, its retreat and deflection allow the force state of the hard rock point to change from a single positive impact to a composite contact state with axial disturbance and lateral force components, thereby reducing the risk of local breakage of the cutter head 42 and increasing the likelihood of the hard rock block being disturbed and broken.

[0040] When the retracted cutter head 42 continues to rotate with the horizontal tunneling cylinder 30 to a non-primary stress area, or after the corresponding hard rock block has been broken and peeled off, the external resistance experienced by the cutter head 42 decreases. The high-pressure gas chamber 95 in the return reset mechanism 90 pushes the sealed piston 93 to move in the opposite direction, and the hydraulic medium returns from the hydraulic medium storage chamber 94 to the inner cavity of the overpressure relief valve mechanism 80 through the return port 83, causing the first telescopic rod 81 to extend outward. The first telescopic rod 81 pushes the rotating connecting seat 73 to reset, and the roller 75 re-enters the arc-shaped high point range of the limiting contact track 72. The connecting shaft 74 drives the cutter holder 41 and the cutter head 42 back to the normal tunneling position. This reset process is completed jointly by the return reset mechanism 90, the overpressure relief valve mechanism 80, and the arc-shaped limiting mechanism 70, without the need for additional machine stop adjustments or manual reset operations for individual cutter heads 42.

[0041] This invention can be adapted to existing horizontal cylindrical cutterheads with limited structural modifications. The arc-shaped limiting plate 71 and the limiting contact rail 72 are arranged on the inner wall of the horizontal tunneling cylinder 30. The overpressure relief valve mechanism 80 and the return reset mechanism 90 are arranged on the outer side of the central support cylinder 50. The preload adjustment mechanism 60 is arranged inside the central support cylinder 50. All mechanisms are located inside the horizontal tunneling cylinder 30 or close to its inner wall, without significantly increasing the occupancy of the outer perimeter of the horizontal tunneling cylinder 30. The external structure still uses the spirally arranged cutterheads 42 and spiral guide plates 31 as the main tunneling contact structures, thus increasing the overload relief, reset, and batch preload adjustment capabilities of the cutterheads 42 while maintaining the original tunneling cross-section and installation interface.

[0042] The significant advantages of this invention are that during normal tunneling, the cutter head 41 maintains extended support through the overpressure relief valve mechanism 80, and the cutter head 42 maintains a stable cutting posture, without reducing conventional tunneling efficiency. When encountering high-strength rock blocks, the cutter head 41 can form controlled deflection and slight contraction under the limitation of the limiting contact rail 72, reducing the instantaneous large bite impact of the cutter head 42 and reducing the probability of abnormal wear and breakage of the cutter head 42. After the hard particles are removed, the return reset mechanism 90 uses the hydraulic medium return and high-pressure gas reset action to make the cutter head 42 automatically return to the initial tunneling position. The preload adjustment mechanism 60 can simultaneously adjust the opening pressure of multiple overpressure relief valve mechanisms 80, so that the same cutting tooth structure can adapt to vertical shaft formations with different hardness and different proportions of inclusion blocks.

[0043] The above are merely embodiments of this application and are not intended to limit the scope of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of the claims of this application.

Claims

1. A cutting-type cutting tooth structure for vertical shaft excavation, characterized in that, Includes connecting arm, end face sealing plate, horizontal tunneling cylinder, tunneling cutter, central support cylinder, preload adjustment mechanism, arc limit mechanism, overpressure relief valve mechanism and return reset mechanism; The horizontal tunneling cylinder is disposed between the two end face sealing plates, and the central support cylinder is coaxially disposed inside the horizontal tunneling cylinder and connected to the power output end of the connecting arm; The two sets of tunneling cutters are spirally arranged on the outer circumference of the horizontal tunneling cylinder. The tunneling cutters include a telescopic and rotatable cutter holder and a cutter head inclinedly arranged at the outer end of the cutter holder. The arc-limiting mechanism is disposed on the inner wall of the horizontal tunneling cylinder and connected to the cutterhead. The overpressure relief valve mechanism abuts against the arc-limiting mechanism. The reflux reset mechanism is connected to the overpressure relief valve mechanism. The preload adjustment mechanism is disposed in the central support cylinder and abuts against the preload push rod of the overpressure relief valve mechanism.

2. The cutting-type cutting tooth structure for vertical shaft excavation according to claim 1, characterized in that, The tunneling cutter also includes a sealing ring, which is fixedly disposed on the outer wall of the horizontal tunneling cylinder. The cutter holder is telescopically and rotatably disposed inside the sealing ring. The cutter head is detachably connected to the outer end of the cutter holder and is inclined toward the area where the end face sealing plate is located.

3. The cutting-type cutting tooth structure for vertical shaft excavation according to claim 1, characterized in that, The arc-shaped limiting mechanism includes an arc-shaped limiting plate, a limiting contact rail, a rotating connecting seat, a connecting shaft, and rollers. The arc-shaped limiting plate is fixedly installed on the inner wall of the horizontal tunneling cylinder. The limiting contact rail is installed on the arc-shaped inner wall of the arc-shaped limiting plate. The outer end of the connecting shaft is fixedly connected to the cutter holder. The rotating connecting seat is fixedly connected to the inner end of the connecting shaft. At least two rollers are installed on the rotating connecting seat and roll against the inner side of the limiting contact rail.

4. The cutting-type cutting tooth structure for vertical shaft excavation according to claim 3, characterized in that, The limiting contact track is an arc-shaped closed-loop ring adapted to the curvature of the inner wall of the horizontal tunneling cylinder. The limiting contact track has an arc-shaped high point interval for at least two of the rollers to abut. The rotating connecting seat forms a combined constraint structure of rotation and radial extension with the limiting contact track through the rollers.

5. The cutting-type cutting tooth structure for vertical shaft excavation according to claim 3, characterized in that, The overpressure relief valve mechanism includes a first telescopic rod, an overflow port, a return port, and a pre-tightening force push rod. The outer end of the first telescopic rod is rotatably supported on the inner end face of the rotating connecting seat by a bearing. The inner cavity of the overpressure relief valve mechanism stores incompressible fluid. The overflow port and the return port are respectively disposed on the outer wall of the cavity of the overpressure relief valve mechanism. The pre-tightening force push rod is pressed against the sealing element disposed in the overflow port channel by an elastic element.

6. The cutting-type cutting tooth structure for vertical shaft excavation according to claim 5, characterized in that, The reflux reset mechanism includes a reflux drive cylinder, a second telescopic rod, a sealing piston, a hydraulic medium storage chamber, and a high-pressure gas chamber. The reflux drive cylinder is fixed on the outer wall of the overpressure relief valve mechanism. The sealing piston is movably disposed inside the reflux drive cylinder. The hydraulic medium storage chamber is located on the side of the sealing piston near the overflow port and the reflux port. The high-pressure gas chamber is located on the other side of the sealing piston. The second telescopic rod is disposed inside the high-pressure gas chamber and supports the sealing piston. One-way valves are respectively provided at the docking points of the overflow port and the reflux port with the hydraulic medium storage chamber.

7. The cutting-type cutting tooth structure for vertical shaft excavation according to claim 5, characterized in that, An overflow valve mounting seat is fixedly provided on the outer wall of the central support cylinder. Multiple overpressure overflow valve mechanisms are respectively fixedly provided on the corresponding overflow valve mounting seats. Multiple pre-tightening push rods pass through the central support cylinder and the overflow valve mounting seat and extend into the inner cavity of the central support cylinder.

8. The cutting-type cutting tooth structure for vertical shaft excavation according to claim 7, characterized in that, The preload adjustment mechanism includes a moving shaft, an inclined drive seat, an internal thread drive cylinder, a worm gear, a worm, and a polygonal limiting seat. The moving shaft is located in the middle of the inner cavity of the central support cylinder. Multiple inclined drive seats are located on the outer circumferential surface of the moving shaft. The inner ends of each preload push rod slide against the inclined outer wall of the corresponding inclined drive seat. The internal thread drive cylinder is screwed to the outside of one end of the moving shaft and rotatably limited within the central support cylinder. The worm gear is fixedly located on the outer wall of the internal thread drive cylinder. The worm is located at the end of the central support cylinder and meshes with the worm gear. The other end of the moving shaft has a polygonal outer contour. The polygonal limiting seat is fixedly located on the inner wall of the central support cylinder and slides in cooperation with the polygonal outer contour of the moving shaft.

9. The cutting-type cutting tooth structure for vertical shaft excavation according to claim 1, characterized in that, Each group of tunneling cutters is provided with a corresponding spiral guide plate, which is fixedly installed on the outer wall of the horizontal tunneling cylinder, and the spiral direction of the spiral guide plate is consistent with the spiral arrangement direction of the tunneling cutters in the corresponding group; multiple reinforcing ribs are provided between the end face sealing plate and the edge of the horizontal tunneling cylinder.

10. A method for preventing wear on a cutting-type cutting tooth structure used in vertical shaft excavation, comprising the cutting-type cutting tooth structure as described in any one of claims 1-9, characterized in that, Includes the following steps: The power output end of the connecting arm drives the central support cylinder and the horizontal tunneling cylinder coaxially arranged with the central support cylinder to rotate, so that the two sets of tunneling cutters arranged in a spiral on the outer circumference of the horizontal tunneling cylinder can tunnel the area in front of the shaft. The cutting head of the tunneling cutter participates in the tunneling along with the cutter holder. The cutting head contacts the rock mass in an inclined posture. The cutter holder has extension and rotation margins relative to the horizontal tunneling cylinder under the constraint of the arc limiting mechanism. When the tunneling resistance experienced by the cutter head is transmitted to the cutter holder and the arc-limiting mechanism, the arc-limiting mechanism transmits the force to the overpressure relief valve mechanism, and the overpressure relief valve mechanism constrains the position of the cutter holder under the overflow opening pressure limited by the preload rod. When the overpressure relief valve mechanism overflows, the tool holder extends and deflects relative to the arc limiting mechanism. The return reset mechanism is connected to the overpressure relief valve mechanism and returns to it, so that the tool holder and the tool head are reset.

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