Constant-adjusting installation mechanism for down pressure of cutter wheel of special-shaped cutting machine

Abstract

The present application relates to cutting equipment technical field, specifically to a kind of constant adjustment installation mechanism of knife wheel down pressure for special-shaped cutting machine, including base, guide rail and tool holder, guide rail is fixedly connected on base, tool holder is slidably connected on base by guide rail, the lower end of tool holder is fixedly connected with knife wheel assembly, liquid driving mechanism is fixedly connected on base, the output end of liquid driving mechanism is located downside, and the lower end of liquid driving mechanism is fixedly connected with connecting frame, the bottom center of connecting frame is fixedly connected with guide column coaxially, guide column extends vertically downward, and floating sleeve is slidably arranged on the outer coaxial center of guide column.The present application is provided with guide column, floating sleeve, main control spring and compensation assembly consisting of compensation swing arm, follow-up roller and tension spring, can realize the passive constant adjustment of knife wheel down pressure by pure mechanical structure, without additional introduction of electric control or gas control constant pressure system, structure is simple and reliable, and manufacturing cost is lower.

Description

Technical Field

[0001] This invention relates to the field of cutting equipment technology, specifically to a constant pressure adjustment mechanism for the cutting wheel of an irregular-shaped cutting machine. Background Technology

[0002] In irregular-shaped cutting equipment for sheet metal workpieces, the downward pressure mechanism of the cutter wheel typically employs either a liquid-driven mechanism or a cam-driven structure. During actual processing, due to the microscopic undulations of the workpiece material surface and the spatial dynamic response changes caused by the switching of high-frequency machining trajectories, the cutter wheel assembly inevitably experiences high-frequency and severe axial reverse movement when moving at high speed along the irregular trajectory. This high-frequency movement directly disrupts the energy balance of the original drive system, resulting in severe and uncontrollable instantaneous fluctuations in the axial downward pressure acting on the cutter wheel assembly.

[0003] To address the aforementioned issue of pressure fluctuation, the industry has implemented the following improvement measures: For liquid-driven mechanisms, high-precision pressure sensors and electrically controlled brake valves are typically installed in the fluid circuit, and electronic closed-loop control algorithms are used for real-time pressure compensation; for cam-driven mechanisms, a mechanically stiffer buffer spring is usually added between the cam follower and the tool holder, or a rigidly aligned hard follower cam structure is fabricated by strictly pre-modeling the workpiece surface.

[0004] While the existing solutions can handle conventional low-speed machining, in high-speed, precision machining of irregular shapes, the inherent compressibility of fluid transmission and the mechanical lag of the electronic control system mean that their adaptive adjustment speed to high-frequency undulations always lags behind the actual fluctuations of the cutting surface. This leads to instantaneous pressure overshoot at the interface of undulations, causing workpiece chipping, breakage, or tool damage; or pressure undershoot, resulting in insufficient machining depth and missed cut lines. Furthermore, electronic control components are prone to failure in the environment of cutting vibration and debris contamination. Cam mechanisms, being fixed geometric contouring mechanisms, rely entirely on preset contour curves for compensation and therefore cannot adapt to the random, uncertain micro-undulations on the workpiece surface. If only a buffer spring is used, the spring's stiffness response and residual vibration will exacerbate pressure fluctuations when facing high-frequency, large-amplitude undulations. In addition, under the reverse high-frequency impact generated by high-speed machining, the hard contact surface between the cam and the follower is prone to severe mechanical wear, causing the pressure regulation accuracy to deteriorate exponentially over time and resulting in an extremely short service life. Summary of the Invention

[0005] The purpose of this invention is to provide a constant pressure adjustment mechanism for the cutting wheel of a non-circular cutting machine, so as to solve the problem that the existing constant pressure adjustment scheme mentioned in the background art has a lag response and cannot adapt to the high-frequency movement under high-speed non-circular cutting.

[0006] To achieve the above objectives, the present invention provides the following technical solution: A constant pressure adjustment mounting mechanism for a cutting wheel in an irregular-shaped cutting machine includes a base, a guide rail, and a cutting wheel holder. The guide rail is fixedly connected to the base, and the cutting wheel holder is slidably connected to the base via the guide rail. A cutting wheel assembly is fixedly connected to the lower end of the cutting wheel holder. A liquid drive mechanism is fixedly connected to the base, with its output end located at the lower side. A connecting frame is fixedly connected to the lower end of the liquid drive mechanism, and a guide post is coaxially fixedly connected to the bottom center of the connecting frame. The guide post extends vertically downwards, and its outer surface is... A floating sleeve is slidably fitted around the shaft. The bottom end of the floating sleeve is fixedly connected to the tool holder. A main control spring is fitted around the guide post. The main control spring is axially restricted between the connecting frame and the floating sleeve. A compensation component is also provided between the connecting frame and the floating sleeve. The compensation component includes a pair of swing brackets that are symmetrically hinged to the outer walls of both sides of the connecting frame. The lower ends of the swing brackets on both sides are hinged to compensation arms. The free end of each compensation arm is rotatably connected to a follower roller. The follower roller is in rolling connection with the floating sleeve.

[0007] The tool holder is slidably connected to the base via guide rails, and the lower connecting frame is driven by a liquid drive mechanism. This, along with a vertically extending guide post, a slidingly fitted floating sleeve, and a main control spring, forms an axially floating foundation support frame. When the tool wheel assembly axially shifts due to the undulations of the workpiece's irregular surface, the floating sleeve slides relative to the guide post and is elastically supported by the main control spring, achieving flexible tool feed. Furthermore, a compensation assembly including a swing bracket, a compensating arm, and a follower roller is installed between the connecting frame and the floating sleeve. When the floating sleeve undergoes axial dynamic floating displacement, the paired and axisymmetrically hinged swing brackets and compensating arms on both sides of the connecting frame move in tandem, forcing the free-end follower roller to maintain dynamic rolling contact with the outer wall of the floating sleeve. This establishes a mechanical dynamic transmission chain at the structural level, converting vertical axial linear displacement into diagonal spatial displacement, providing a highly rigid mechanical solid support for subsequent nonlinear mechanical balancing. Furthermore, this linkage structure guides the disordered axial impact to the symmetrical mechanical supports on both sides for dispersion and absorption, avoiding the mechanical response lag caused by traditional single-spring structures or rigid installation structures during irregular cutting. It effectively prevents defects such as gravity-induced tool impact and high-frequency vibration of cutting reaction force during the cutting process, ensuring the axial stability and basic assembly accuracy of the tool wheel assembly during irregular cutting.

[0008] Preferably, the compensation assembly further includes a tension spring, with a tension spring provided between the two compensation rotating arms. The two ends of the tension spring are respectively hinged to the two compensation rotating arms, and the central axis of the tension spring is perpendicular to the central axis of the guide column. A pair of guide rail grooves are symmetrically arranged on the outer wall of the floating sleeve. The sidewall of the guide rail groove is set as a forward-inclined slope. The two follower rollers are respectively nested in the corresponding guide rail grooves, and under the continuous tension of the tension spring, the two follower rollers respectively maintain rolling contact with the bottom working surface of the corresponding guide rail groove.

[0009] By laterally tensioning a tension spring between the symmetrically distributed compensating arms on both sides, and ensuring that its central axis is spatially perpendicular and orthogonal to the guide post, a pair of guide rail grooves are symmetrically opened on the outer wall of the floating sleeve to nest the follower rollers. During the machining of irregular surfaces and adaptive adjustment of downward pressure, the high-state tension force continuously output by the lateral tension spring acts on the compensating arms through the hinge point, forcing the follower rollers on both sides to be firmly pressed against the bottom working surface of the guide rail groove with high tightness throughout the entire stroke range. This eliminates the assembly and dynamic sliding clearance between the follower rollers and the guide rail groove, and realizes zero-clearance following of the rolling pair. Furthermore, during the axial reciprocating displacement of the floating sleeve with the tool holder, the main control spring generates a linear positive stiffness elastic force increment due to axial compression deformation. At the same time, the elastic restoring force generated by the stretching of the transverse tension spring as the swing arm swings is orthogonally decomposed at the geometric contact interface between the working surface of the follower roller and the bottom of the guide rail groove, resulting in a reverse nonlinear component force in the vertical axis. The two forces undergo real-time dynamic vector synthesis and mechanical energy offset in space, thereby constructing a passive zero-stiffness constant pressure adjustment network in the purely mechanical dimension. This effectively prevents the problem of drastic pressure fluctuations caused by the natural compression of mechanical elastic elements, avoids process defects such as incomplete cutting, substrate crushing, or cutting trajectory deviation, and ensures accurate positioning and constant pressure trajectory accuracy of thin plates and irregularly shaped workpieces during cutting.

[0010] Preferably, the guide rail groove includes a convex arc surface segment and a concave arc surface segment, the convex arc surface segment is disposed on the upper side of the concave arc surface segment, and the convex arc surface segment is tangent to the concave arc surface segment.

[0011] By dividing the working surface of the guide rail groove into a spatial geometric configuration composed of convex and concave arc segments, and placing the convex arc segment above the concave arc segment with both maintaining tight tangency at the spatial transition, the follower roller, starting from the nominal equilibrium center, seamlessly transitions and rolls within the convex or concave arc segment along a smooth, tangent arc trajectory. During this process, the included angle of the tangent at the tangent point continuously evolves due to the nonlinear spatial abrupt change in the curvature of the convex and concave sections, forcibly constraining and altering the slope of the vertical axial component of the transverse tension spring acting on the groove wall. This results in a precise nonlinear negative stiffness characteristic completely opposite to the linear increment direction of the main control spring, thus achieving perfect mechanical self-balancing constant pressure counterbalancing at every micro-displacement point throughout the full floating stroke. Furthermore, by utilizing the tangential design of the first and second order analytical continuity of the convex and concave arc segments, the curvature abrupt change and geometric hard collision of the roller during high-speed reversing motion are eliminated. Its nonlinear curvature slope breaks the resonance period of high-frequency surging energy during high-speed cutting, forming a natural variable frequency mechanical damping self-absorbing vibration structure. This effectively prevents the high-frequency impact energy from being directly transmitted to the tool wheel assembly, thus preventing micro-fatigue spalling or chipping defects of the cutting edge. It significantly improves the dynamic vibration resistance stiffness and tool life of the entire mechanism.

[0012] Preferably, each of the two compensation arms is provided with a fine-adjustment bolt, which is threadedly connected to either of the compensation arms, and the output end of the fine-adjustment bolt is connected to a tension spring.

[0013] By installing fine-tuning bolts on both sides of the compensation arm, with the bolts threadedly connected to the compensation arm on one side and their output ends directly connected to the hook end of the tension spring, the circumferential angle of the fine-tuning bolts is rotated during initial offline calibration or adjustment for switching between different processing batches. This utilizes the high transmission ratio of the threaded pair to drive the hook end of the tension spring to generate a precise axial displacement, thereby quantitatively and accurately adjusting the axial tensile length and lateral reference preload amplitude of the tension spring in its initial state. The adjusted lateral reference force is amplified and spatially transmitted through the torque of the compensation arm and the follower roller, ultimately mapping to a quantitative on-site adjustment of the initial reference value of the nominal output constant downward pressure of the entire installation mechanism. This endows the constant pressure adjustment mechanism with excellent adaptability to different working conditions, perfectly matching the processing requirements of plates with different material hardness and thickness. It effectively prevents production quality problems such as thin plate cracking due to excessive initial preload or incomplete cutting due to insufficient initial preload, simplifies the alignment operation logic during manual or automated deployment, and ensures the system's high efficiency and production quality stability.

[0014] Preferably, the bottom of the connecting frame is provided with a limiting step, and when the upper end of the floating sleeve moves to the limit position under excessive external impact, the floating sleeve and the limiting step are rigidly limited and abutted.

[0015] By machining or fixing a limiting step at the bottom of the connecting frame, a floating sleeve is used to drive the tool holder to instantly and rapidly move upwards against the elastic resistance of the main control spring and compensation components during high-speed continuous cutting of irregular shapes. When it moves to the designed safe limit position, the upper end of the floating sleeve will immediately make large-area rigid contact with the limiting step at the bottom of the connecting frame, thus directly locking the axial degree of freedom of the floating sleeve to continue moving upwards. This structural design rigidly transmits the extremely severe and destructive axial impact reaction force directly to the connecting frame and disperses it onto the rigid outer shell and base of the liquid drive mechanism, bypassing the sensitive follower rollers, guide rail grooves, and tension springs, thus forming a rigid unloading and deadlock protection mechanism under high overload conditions. This effectively prevents the follower rollers from slipping out of the guide rail groove boundary due to excessive stroke or the tension spring from undergoing superplastic fracture failure under high-frequency heavy loads, ensuring the overall structural integrity and resistance to damage of the installation mechanism under continuous alternating severe loads.

[0016] Preferably, the lower end of the guide post is provided with a buffer pad, the distance between the lower end face of the buffer pad and the bottom of the floating sleeve is S1, and the distance between the lower end of the limiting step and the upper end of the floating sleeve is S2, where S1 < S2.

[0017] By assembling a buffer pad at the lower end of the guide post, and strictly limiting the distance S1 between the lower end face of the buffer pad and the bottom of the floating sleeve to be less than the distance S2 between the lower end of the limiting step and the upper end of the floating sleeve, when the liquid drive mechanism drives the entire mounting mechanism to perform rapid downward feed, or when the cutter wheel assembly rapidly slides downward under the high elasticity of the main control spring after passing over a high protrusion, due to the geometric dimensions satisfying S1 < S2, the bottom inner wall surface of the floating sleeve will preferentially make physical contact with the buffer pad at the bottom of the guide post on the downward path. Utilizing the high internal resistance rheological properties of the buffer pad's flexible material, most of the downward reset kinetic energy is absorbed, converted, and dissipated in a very short time, providing crucial axial flexible mechanical damping for the system. After this, if residual kinetic energy still exists or the system is under extreme overload, rigid end faces such as limiting steps provide auxiliary rigid bearing, thereby constructing a stepped composite protection system in space and time, which first provides flexible energy dissipation and vibration absorption and then rigid limit safety limitation. This effectively prevents the blade breakage or sliding pair wear caused by strong hard impact or rigid impact during high-speed mechanical reset, and significantly improves the smoothness of operation and fatigue life of the component under long-term frequent floating conditions.

[0018] Preferably, the bottom working surface of the guide rail groove is continuously machined with multiple grease reservoirs with a depth of no more than 0.2 mm.

[0019] Multiple grease reservoirs, no deeper than 0.2 mm, are continuously and precisely machined on the working surface at the bottom of the guide rail groove. Utilizing the capillary physical adsorption effect and the viscous properties of the fluid dynamics generated by these micro-reservoirs, the grease is firmly locked in and evenly distributed along the rolling path. When the follower roller moves under extremely harsh conditions of high pressure, high speed, and high frequency reciprocating rolling, the contact surface always maintains a high-quality fluid lubrication or boundary lubrication state, reducing the coefficient of friction to its limit. This effectively prevents geometric deformation, scratches, or deterioration of the precision variable curvature profile of the guide rail groove caused by long-term hard mechanical fretting wear. Furthermore, the micro-depth grease reservoirs also act as physical collection traps for wear particles and external dust, preventing abrasive wear caused by hard foreign objects intruding into the rolling surface. This fundamentally locks in the repeatability and adjustment stability of the entire nonlinear constant pressure compensation network, significantly extending the precision lifespan and maintenance-free operation time of the mechanism in continuous industrial production.

[0020] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. By setting a guide column, a floating sleeve, a main control spring, and a compensation assembly consisting of a compensation arm, a follower roller, and a tension spring, the present invention can achieve passive constant adjustment of the pressure under the cutter wheel by relying on a purely mechanical structure. It does not require the introduction of an additional electronic or pneumatic constant pressure system, and the structure is simple, reliable, and has a lower manufacturing cost.

[0021] 2. This invention eliminates the clearance between the follower roller and the guide rail groove by using the tension spring preload, and uses the tension spring component force to offset the elastic force increment of the main control spring, thus constructing a passive zero stiffness constant pressure adjustment network. This effectively avoids cutting defects caused by pressure fluctuations and ensures the cutting accuracy and processing quality of irregular workpieces.

[0022] 3. This invention utilizes a special guideway groove configuration where the convex and concave arc sections are tangent. This configuration can accurately derive a nonlinear negative stiffness component force that is opposite to the linear increment of the main control spring, thereby achieving mechanical self-balancing at the micro-displacement point throughout the entire stroke. It also has a damping and vibration absorption effect, reducing impact damage to the tool wheel and extending the tool's service life.

[0023] 4. This invention can quantitatively calibrate the initial preload by adding a fine-tuning bolt, adapting to the processing requirements of workpieces of different thicknesses and materials, improving the adaptability to working conditions, and ensuring stable production quality; the stepped limit protection structure, with flexible buffering followed by rigid limiting, can effectively absorb impact kinetic energy, avoid hard collision damage, and further improve structural reliability and service life; the addition of a micro-fine grease reservoir can maintain long-term lubrication of the rolling pair, collect wear particles, reduce the risk of abrasive wear, and extend the accuracy maintenance cycle and maintenance-free cycle of the mechanism. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the cutter wheel and base assembly of the irregular shape cutting machine of the present invention; Figure 2 This is a top view of the blade wheel and base assembly of the irregular shape cutting machine of the present invention; Figure 3 for Figure 2 Full sectional view at point AA; Figure 4 for Figure 3 A magnified view of a section at point C; Figure 5 for Figure 2 Full sectional view at point BB; Figure 6 for Figure 5 A magnified view of a section at point D; Figure 7 This is a schematic diagram of the connecting frame, compensating swing arm, and floating sleeve in this invention.

[0025] In the diagram: 1. Base; 2. Guide rail; 3. Tool holder; 4. Tool wheel assembly; 5. Liquid drive mechanism; 6. Connecting frame; 7. Guide column; 8. Floating sleeve; 9. Main control spring; 10. Compensation assembly; 11. Swing bracket; 12. Compensating swing arm; 13. Follower roller; 14. Tension spring; 81. Guide rail groove; 811. Convex arc section; 812. Concave arc section; 15. Fine adjustment bolt; 61. Limiting step; 16. Buffer pad; 82. Grease reservoir. Detailed Implementation

[0026] Please see Figures 1 to 7 This invention provides a constant pressure adjustment and mounting mechanism for the cutting wheel of an irregular-shaped cutting machine, the technical solution of which is as follows: Please refer to the mounting mechanism for constant downward pressure adjustment of the blade wheel in an irregular-shaped cutting machine. Figures 1 to 7The system includes a base 1, a guide rail 2, and a tool holder 3. The guide rail 2 is fixedly connected to the base 1, and the tool holder 3 is slidably connected to the base 1 via the guide rail 2. A tool wheel assembly 4 is fixedly connected to the lower end of the tool holder 3. A liquid drive mechanism 5 is fixedly connected to the base 1. The output end of the liquid drive mechanism 5 is located on the lower side, and a connecting frame 6 is fixedly connected to the lower end of the liquid drive mechanism 5. A guide post 7 is coaxially fixedly connected to the bottom center of the connecting frame 6. The guide post 7 extends vertically downward, and a floating sleeve 8 is coaxially slidably sleeved on the outside of the guide post 7. The bottom end of the cylinder 8 is fixedly connected to the tool holder 3. The guide post 7 is fitted with a main control spring 9. The main control spring 9 is axially restricted between the connecting frame 6 and the floating sleeve 8. A compensation component 10 is also provided between the connecting frame 6 and the floating sleeve 8. The compensation component 10 includes a pair of swing brackets 11 that are symmetrically hinged to the outer walls of both sides of the connecting frame 6. The lower ends of the swing brackets 11 on both sides are hinged with compensation rotating arms 12. The free end of each compensation rotating arm 12 is rotatably connected to a follower roller 13. The follower roller 13 is in rolling connection with the floating sleeve 8.

[0027] The compensation assembly 10 also includes a tension spring 14. A tension spring 14 is provided between the two compensation rotating arms 12. The two ends of the tension spring 14 are respectively hinged to the two compensation rotating arms 12, and the central axis of the tension spring 14 is perpendicular to the central axis of the guide post 7. A pair of guide rail grooves 81 are symmetrically arranged on the outer side wall of the floating sleeve 8. The side wall of the guide rail groove 81 is a forward-inclined slope. The vertical projection of the front side of the floating sleeve 8 is an isosceles trapezoid, and the top edge of the isosceles trapezoid is located on the front side. The two follower rollers 13 are respectively nested in the corresponding guide rail grooves 81, and under the continuous tension of the tension spring 14, the two follower rollers 13 Each roller maintains rolling contact with the bottom working surface of the corresponding guide rail groove 81. The guide rail groove 81 includes a convex arc section 811 and a concave arc section 812. The convex arc section 811 is located on the upper side of the concave arc section 812, and the convex arc section 811 and the concave arc section 812 are tangent. The initial position of the follower roller 13 is located at the tangent connection between the convex arc section 811 and the concave arc section 812, and this connection constitutes the nominal center balance point. Both sides of the compensation rotating arm 12 are provided with fine adjustment bolts 15. The fine adjustment bolts 15 are threadedly connected to either side of the compensation rotating arm 12, and the output end of the fine adjustment bolts 15 is connected to the tension spring 14.

[0028] To clarify the mechanical matching relationship between the working surface of the guide groove 81 and the main control spring 9, the position of the floating sleeve 8 when it is in the nominal center position is taken as the zero point of displacement, and the upward displacement of the floating sleeve 8 relative to the guide post 7 is recorded as x, where x=0 represents the nominal center position, x>0 represents the floating sleeve 8 being driven upward by the workpiece convexity of the cutter wheel assembly 4, and x<0 represents the floating sleeve 8 being lowered relative to the nominal center position when the cutter wheel assembly 4 enters the concave area of ​​the workpiece surface.

[0029] Let the spring stiffness of the main control spring 9 be k1, and the pre-compression of the main control spring 9 under the nominal neutral position be δ0. Then, when the floating sleeve 8 generates a displacement x, the axial downward pressure F1 exerted by the main control spring 9 on the floating sleeve 8 satisfies: F1(x)=k1(δ0+x) (1; As shown in equation (1), when the floating sleeve 8 floats upward a distance x from its nominal center position, the main control spring 9 is further compressed, and its axial downward pressure increases by k1·x relative to the nominal center position. Conversely, when the floating sleeve 8 floats downward, the compression of the main control spring 9 decreases, and its axial downward pressure decreases accordingly. Therefore, this invention does not change the linear elastic characteristics of the main control spring 9 following Hooke's law, but uses the compensation component 10 to generate an axial compensation force that is opposite to the trend of the above-mentioned elastic force increment, so as to reduce the influence of the floating displacement on the total downward pressure of the cutter wheel.

[0030] Let F0 be the target downward pressure that the cutter wheel assembly 4 needs to maintain within its designed working stroke, and let F2 be the equivalent axial downward pressure exerted by the compensation assembly 10 on the floating sleeve 8. Then, under the design condition of neglecting the rolling pair friction, the following needs to be satisfied: F0 = F1(x) + F2(x) (2); Substituting equation (1) into equation (2), we get: F2(x)=F0-k1(δ0+x)=F20-k1x (3); Where F20=F0-k1δ0 is the axial reference compensation force provided by the compensation component 10 in the nominal neutral state.

[0031] Therefore, when the floating sleeve 8 moves upward, the axial force of the main control spring 9 increases according to the law of k1x, while the compensation component 10 needs to gradually decrease its axial compensation force according to the corresponding law; when the floating sleeve 8 moves downward, the axial force of the main control spring 9 decreases, and the axial compensation force of the compensation component 10 increases accordingly. The two change trends are opposite, thus keeping the total downward pressure after the combination of the two at the target value F0 within the designed floating stroke.

[0032] Furthermore, let the spring stiffness of tension spring 14 be k2, the free length of tension spring 14 be L0, and the actual length of tension spring 14 when the displacement of floating sleeve 8 is x be L(x). Then the tension T generated by tension spring 14 satisfies: T(x) = k2[L(x) - L0] (4); Since the tension spring 14, the compensating arm 12, and the follower roller 13 together form a mechanical force transmission mechanism, when the floating sleeve 8 undergoes a small displacement dx, the compensating arm 12 simultaneously undergoes an angular displacement, causing a corresponding change dL in the length of the tension spring 14. According to the virtual work balance relationship, the equivalent compensating force F2 generated by the compensating component 10 in the axial direction of the floating sleeve 8 satisfies the following relationship with the tension force T of the tension spring 14 and the rate of change of the spring length relative to the floating displacement: F2(x)=T(x)·dL(x) / dx (5); Substituting equations (3) and (4) into equation (5), we obtain the basic design relationship that the guide rail groove 81 needs to satisfy: k2[L(x)-L0]·dL(x) / dx=F20-k1x (6); As can be seen from equation (6), the constant pressure adjustment mounting mechanism for the blade wheel of the irregular cutting machine provided by the present invention does not use the tension spring 14 to generate a nonlinear elastic force that violates Hooke's law, but rather makes the change in length of the tension spring 14 and the axial displacement of the floating sleeve 8 form a nonlinear motion conversion relationship, thereby changing the mechanical transmission ratio of the tension spring 14 transmitted to the floating sleeve 8 through the compensation arm 12 and the follower roller 13, so that the final axial compensation force changes according to the law of equation (3).

[0033] Let Le be the actual length of the tension spring 14 in the nominal neutral position. Integrating equation (6) over the nominal working stroke, we can obtain: [L(x)-L0]²=[Le-L0]²+(2F20 / k2)x-(k1 / k2)x² (7); This yields the design length of tension spring 14 at different floating displacement positions: L(x)=L0+√{[Le-L0]²+(2F20 / k2)x-(k1 / k2)x²} (8); Equation (8) represents the design correspondence between the change in the length of the tension spring and the axial displacement of the floating sleeve in this embodiment. Within the designed working stroke, by selecting the main control spring stiffness k1, the tension spring stiffness k2, the initial pre-tension amount Le-L0, and the target downward pressure F0, the value within the square root of Equation (8) is always greater than zero, thus obtaining the corresponding length that the tension spring 14 should have at each axial displacement position of the floating sleeve 8.

[0034] Furthermore, the hinge axis between the compensating arm 12 on one side and the swing bracket 11 is denoted as the rotation center O, and the two rotation centers O on both sides are symmetrically arranged with respect to the central axis of the guide column 7. The distance between the rotation center O on one side and the connection position of the tension spring 14 is denoted as a, the distance between the rotation center O and the center of the follower roller 13 is denoted as b, half of the distance between the two rotation centers O is denoted as d, and the swing angle of the compensating arm 12 relative to the vertical direction is denoted as θ.

[0035] Since the two compensating rotating arms 12 and their spring connection positions are symmetrically arranged about the central axis of the guide post 7, the actual length L of the spring 14 and the swing angle θ of the compensating rotating arm 12 satisfy the following relationship in the coordinate direction established in this embodiment: L(x) = 2[da·sinθ(x)] (9); From equations (8) and (9), we can obtain the target swing angle that the compensating swing arm 12 should be at when the floating sleeve 8 is at any design displacement x: θ(x)=arcsin{[dL(x) / 2] / a} (10); Therefore, given the already determined main control spring 9, tension spring 14, compensating rotating arm 12, and mechanism installation dimensions, for each determined axial displacement x generated by the floating sleeve 8, the target length of the tension spring 14 can be determined according to equation (8), and the target positions of the compensating rotating arm 12 and the follower roller 13 can be determined according to equation (10). The working surface of the bottom of the guide rail groove 81 can be determined in reverse by the continuous target positions of the follower roller 13 under each floating displacement x, instead of arbitrarily selecting convex or concave arcs for splicing.

[0036] Specifically, with the connecting frame 6 as a fixed reference system, the distance from the center of the follower roller 13 to the rotation center O of the compensating arm 12 is always b. The lateral and vertical positions of the center of the follower roller 13 in the fixed reference system can be determined by the target swing angle θ(x) of the compensating arm 12. Since the guide groove 81 is set on the side wall that moves axially synchronously with the floating sleeve 8, the continuous motion trajectory of the center of the follower roller 13 relative to the floating sleeve 8 can be obtained by further deducting the axial displacement x of the floating sleeve 8 itself.

[0037] The continuous motion trajectory is denoted as the roller center trajectory C. By offsetting the radius r of the follower roller 13 along the roller center trajectory C in the normal direction pointing to the working surface of the bottom of the guide rail groove 81, the working curve of the bottom of the guide rail groove 81 can be obtained. In other words, the working surface of the bottom of the guide rail groove 81 is an equidistant offset surface formed by the roller center design trajectory according to the radius r of the follower roller 13.

[0038] In the actual design and processing, multiple axial displacements x can be selected sequentially within the designed floating stroke of the floating sleeve 8. Each displacement value is then substituted into equations (8) and (10) to obtain the corresponding length L of the tension spring 14, the swing angle θ of the compensating swing arm 12, and the center position of the follower roller 13. The calculated center positions of the multiple follower rollers 13 are then input into the three-dimensional design software to form a continuous trajectory. The follower rollers 13 are then offset equidistantly according to their actual radius, thereby directly generating the machining profile of the bottom working surface of the guide rail groove 81. The generated working surface can be machined by CNC milling or grinding.

[0039] In the above surface construction process, the position of the follower roller 13 corresponding to x=0 is taken as the nominal center equilibrium point. The working surface above this equilibrium point forms a convex arc surface segment 811, and the working surface below this equilibrium point forms a concave arc surface segment 812. Since both the convex arc surface segment 811 and the concave arc surface segment 812 are formed by the roller center trajectory determined by the same continuous function relationship, the two working surfaces have a continuous tangential direction at the nominal center, thereby avoiding sudden changes in transmission angle and rigid impact when the follower roller 13 passes through the nominal center.

[0040] Fine-tuning bolts 15 are installed on both sides of the compensation rotating arm 12. The fine-tuning bolts 15 are threaded to the compensation rotating arm 12 and cooperate with the connecting end of the tension spring 14. In the initial installation and debugging state of the equipment, the position of the connecting end of the tension spring 14 can be changed by rotating the fine-tuning bolts 15 to make a slight correction to the initial pretension of the tension spring 14, so that the initial tension after actual assembly matches the design initial tension determined according to the above mechanical relationship, thereby compensating for the manufacturing tolerance, assembly size error and elastic parameter deviation of the tension spring 14 after long-term operation. Within the allowable adjustment range, the reference downward pressure of the cutter wheel assembly 4 can also be slightly corrected.

[0041] The bottom of the connecting frame 6 is provided with a limiting step 61, and the lower end of the guide post 7 is provided with a buffer pad 16. The initial distance between the lower end face of the buffer pad 16 and the bottom of the floating sleeve 8 is S1, and the initial distance between the lower end of the limiting step 61 and the upper end of the floating sleeve 8 is S2, and S1 < S2. When the cutter wheel assembly 4 encounters a workpiece protrusion or sudden impact that exceeds the normal compensation stroke, causing the floating sleeve 8 to move upward rapidly, the bottom of the floating sleeve 8 first contacts the buffer pad 16, and the elastic deformation of the buffer pad 16 absorbs part of the impact kinetic energy of the floating sleeve 8 and the cutter holder 3. When the external impact continues to increase and the buffer pad 16 is further compressed, the upper end of the floating sleeve 8 then makes a rigid limiting contact with the limiting step 61, thus forming a two-stage overload protection structure of first flexible buffering and then rigid limiting, avoiding excessive displacement from directly acting on the follower roller 13, the compensation arm 12 and the tension spring 14.

[0042] Multiple grease reservoirs 82 with a depth of no more than 0.2 mm are continuously arranged on the working surface of the bottom of the guide rail groove 81, and each grease reservoir 82 is filled with lubricating grease. When the follower roller 13 reciprocates along the guide rail groove 81 at high frequency, the grease reservoir 82 can continuously retain lubricating medium near the working surface of the bottom of the groove, so that the follower roller 13 and the guide rail groove 81 maintain a stable rolling lubrication state, and can accommodate some of the tiny wear debris generated by long-term rolling friction, so as to reduce the contour change of the working surface of the guide rail groove 81 caused by wear.

[0043] Working principle: Please refer to Figures 1 to 7Before the mechanism is put into use, the nominal working parameters are first determined according to the required cutting wheel reference pressure F0, the spring stiffness k1 of the main control spring 9 and the spring stiffness k2 of the tension spring 14, and the working surface of the bottom of the guide rail groove 81 is determined according to formulas (6) to (10). After assembly, the initial pre-tension state of the tension spring 14 is calibrated by adjusting the fine bolt 15 so that when the follower roller 13 is located at the connection position of the convex arc section 811 and the concave arc section 812, the compensation component 10 is in the designed nominal center balance state.

[0044] Once the cutting machine enters normal operating condition, the liquid drive mechanism 5 outputs a reference driving force downwards, which acts on the floating sleeve 8 and the tool holder 3 through the connecting frame 6 and the main control spring 9, causing the tool wheel assembly 4 to press the workpiece surface with the set reference downward pressure to perform cutting.

[0045] When the cutter wheel assembly 4 passes over a local protrusion on the workpiece surface, the cutter wheel assembly 4 and the tool holder 3 move upward due to the reverse force of the workpiece surface. The tool holder 3 drives the floating sleeve 8 to float upward along the guide post 7. When the floating sleeve 8 floats upward by a displacement of x, the main control spring 9 is further compressed, and its axial downward pressure increases by k1x according to formula (1).

[0046] At the same time, the guide rail groove 81 set on the outer wall of the floating sleeve 8 moves upward synchronously. The concave arc section 812 of the guide rail groove 81 pushes the follower roller 13 to change position, so that the compensation arm 12 generates a corresponding angular displacement relative to the swing bracket 11, and synchronously changes the distance between the connection points of the tension springs on both sides. Since the working surface of the guide rail groove 81 is determined in reverse according to equations (6) to (10), for every unit increase in axial displacement of the floating sleeve 8, the length of the tension spring 14 and the transmission angle of the compensation arm 12 change according to a predetermined relationship, so that the axial compensation force F2 output by the compensation component 10 gradually decreases according to equation (3).

[0047] Therefore, during the upward floating process of the floating sleeve 8, the increased axial downward pressure of the main control spring 9 and the reduced axial downward pressure of the compensation component 10 cancel each other out, so that the total downward pressure of the cutter wheel combined by the two is maintained near the target downward pressure F0 within the designed floating stroke, thereby suppressing the phenomenon of excessive instantaneous pressure when the cutter wheel assembly 4 passes through the local protrusion.

[0048] Conversely, when the tool wheel assembly 4 enters the local concave area of ​​the workpiece surface from the nominal position, the main control spring 9 pushes the tool holder 3 and the floating sleeve 8 to float downward relative to the guide post 7. At this time, the compression of the main control spring 9 decreases, and the axial downward pressure it generates decreases according to formula (1).

[0049] Simultaneously, the guide groove 81 moves downward with the floating sleeve 8, and the follower roller 13 moves from the nominal center position towards the convex arc section 811. The swing angle of the compensation arm 12 and the length of the tension spring 14 change according to a predetermined nonlinear motion relationship, causing the axial compensation force generated by the compensation component 10 to gradually increase, thereby compensating for the axial force loss caused by the reduced compression of the main control spring 9. Therefore, when the cutter wheel assembly 4 passes through the concave area of ​​the workpiece surface, the total downward pressure of the cutter wheel can also be maintained near the set reference value, reducing the phenomenon of reduced cutting depth, missed cutting, or discontinuous cutting trajectory caused by insufficient downward pressure.

[0050] Therefore, the constant pressure regulation of the present invention does not cause the main control spring 9 or the tension spring 14 to produce an elastic change that is not in accordance with Hooke's law. Instead, it first determines the reverse change compensation force required by the compensation component 10 based on the force change generated by the main control spring 9 during linear compression. Then, it establishes a nonlinear displacement transmission relationship through the tension spring 14, the compensation arm 12, and the variable curvature working surface of the guide groove 81 obtained in reverse according to the target compensation force. This allows the linear elastic force of the tension spring 14 to be converted into the required axial compensation force through a continuously changing mechanical transmission ratio, thereby achieving force matching between the main control spring 9 and the compensation component 10.

[0051] When the mechanism is subjected to a sudden impact exceeding the normal design floating range, the floating sleeve 8 moves upward rapidly and first contacts the buffer pad 16, absorbing the impact energy through the elastic compression of the buffer pad 16. When the impact load increases further, the upper end of the floating sleeve 8 abuts against the limiting step 61, which restricts the floating sleeve 8 from continuing to move upward, so that the impact load exceeding the normal compensation range is transmitted to the base 1 through the connecting frame 6, preventing the follower roller 13 from disengaging from the guide groove 81 and the tension spring 14 and the compensation swing arm 12 from undergoing excessive deformation.

[0052] The specific embodiment of the present invention has been described in detail above with reference to the accompanying drawings. In this embodiment, the specific working surface of the guide rail groove 81 is jointly determined by the stiffness k1 of the main control spring 9, the stiffness k2 of the tension spring 14, the initial length of the tension spring, the effective size of the compensation rotating arm 12, the radius of the follower roller 13, and the target cutting wheel pressure F0, rather than an arbitrarily set nonlinear surface. Those skilled in the art can calculate the continuous position of the follower roller 13 throughout the entire designed floating stroke according to the above-mentioned mechanical relationship based on the actual dimensions of the spring and the mounting mechanism used, and process the corresponding working surface of the guide rail groove 81 accordingly. Adaptive adjustments to the dimensions of each component, the installation direction, and the target downward pressure without departing from the above-mentioned constant pressure compensation principle are all specific implementations of the technical concept of the present invention.

Claims

1. A constant pressure adjustment and mounting mechanism for a cutting wheel of an irregular-shaped cutting machine, characterized in that, The device includes a base (1), a guide rail (2), and a tool holder (3). The guide rail (2) is fixedly connected to the base (1), and the tool holder (3) is slidably connected to the base (1) via the guide rail (2). A tool wheel assembly (4) is fixedly connected to the lower end of the tool holder (3). A liquid drive mechanism (5) is fixedly connected to the base (1). The output end of the liquid drive mechanism (5) is located on the lower side, and a connecting frame (6) is fixedly connected to the lower end of the liquid drive mechanism (5). A guide post (7) is coaxially fixedly connected to the bottom center of the connecting frame (6). The guide post (7) extends vertically downward, and a floating sleeve (8) is coaxially slidably fitted around the guide post (7). The bottom end of the floating sleeve (8) is fixedly connected to the tool holder (3). The guide post (7) is fitted with a main control spring (9). The main control spring (9) is axially restricted between the connecting frame (6) and the floating sleeve (8). A compensation component (10) is also provided between the connecting frame (6) and the floating sleeve (8). The compensation component (10) includes a pair of swing brackets (11) that are symmetrically hinged to the outer walls of both sides of the connecting frame (6). The lower ends of the swing brackets (11) on both sides are hinged with compensation rotating arms (12). The free end of each compensation rotating arm (12) is rotatably connected with a follower roller (13). The follower roller (13) is rollingly connected to the floating sleeve (8).

2. The constant pressure adjustment and mounting mechanism for the cutting wheel of an irregular-shaped cutting machine according to claim 1, characterized in that, The compensation component (10) also includes a tension spring (14). A tension spring (14) is provided between the two compensation rotating arms (12) on both sides. The two ends of the tension spring (14) are respectively hinged to the two compensation rotating arms (12) on both sides. The central axis of the tension spring (14) is perpendicular to the central axis of the guide column (7). A pair of guide rail grooves (81) are symmetrically arranged on the outer side wall of the floating sleeve (8). The side wall of the guide rail groove (81) is set to be a forward inclined surface. The two follower rollers (13) on both sides are respectively nested in the corresponding guide rail grooves (81). Under the continuous tension of the tension spring (14), the two follower rollers (13) respectively maintain rolling cooperation with the bottom working surface of the corresponding guide rail groove (81).

3. The constant pressure adjustment and mounting mechanism for the cutting wheel of an irregular-shaped cutting machine according to claim 2, characterized in that, The guide rail groove (81) includes a convex arc surface section (811) and a concave arc surface section (812). The convex arc surface section (811) is located on the upper side of the concave arc surface section (812), and the convex arc surface section (811) is tangent to the concave arc surface section (812).

4. The constant pressure adjustment and mounting mechanism for the cutting wheel of an irregular-shaped cutting machine according to claim 2, characterized in that, Both sides of the compensation rotating arm (12) are provided with fine adjustment bolts (15), which are threadedly connected to the compensation rotating arm (12) on either side, and the output end of the fine adjustment bolt (15) is connected to the tension spring (14).

5. The constant pressure adjustment and mounting mechanism for the cutting wheel of an irregular-shaped cutting machine according to claim 1, characterized in that, The bottom of the connecting frame (6) is provided with a limiting step (61). When the upper end of the floating sleeve (8) moves to the limit position under excessive external impact, the floating sleeve (8) and the limiting step (61) are rigidly limited and collide.

6. The constant pressure adjustment and mounting mechanism for the cutting wheel of an irregular-shaped cutting machine according to claim 5, characterized in that, The lower end of the guide post (7) is provided with a buffer pad (16), the distance between the lower end face of the buffer pad (16) and the bottom of the floating sleeve (8) is S1, and the distance between the lower end of the limiting step (61) and the upper end of the floating sleeve (8) is S2, where S1 < S2.

7. The constant pressure adjustment and mounting mechanism for the cutting wheel of an irregular-shaped cutting machine according to claim 3, characterized in that, The bottom working surface of the guide rail groove (81) is continuously machined with multiple grease reservoirs (82) with a depth of no more than 0.2 mm.

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