A bevel nut machining tool and a machining process thereof

Abstract

This invention relates to the field of nut assembly processing equipment, and discloses a fixture for machining beveled nuts and its processing technology. The fixture includes a frame base and a control console mounted on the frame base. A dividing plate is provided on the top of the frame base, and several tilting clamping mechanisms are equidistantly arranged along the top edge of the dividing plate. A positioning locking mechanism is provided on one side of each tilting clamping mechanism. This invention, through the coordinated operation of the tilting clamping mechanism and the positioning locking mechanism, abandons the traditional simple fixture's reliance on motor brakes and gear self-locking for limiting positions. During processing, the cutting load is directly borne by the positioning locking mechanism, effectively avoiding workpiece angle deviation and micro-vibration swaying. All machining processes for beveled nuts—drilling, tapping, and bevel milling—are completed in a single clamping operation, eliminating accumulated errors from multiple clamping and positioning operations and significantly improving the dimensional consistency of batch processing.

Description

Technical Field

[0001] This invention belongs to the technical field of nut assembly processing equipment, specifically relating to a tooling for machining inclined nuts and its processing technology. Background Technology

[0002] A bevel nut is a special type of nut where one end face forms a certain angle with the axis. It is widely used in automotive suspension systems, engineering machinery hinge joints, bridge bearings, and aerospace connectors—any application requiring threaded fastening on an inclined mounting surface. Machining a bevel nut involves sequentially performing drilling, tapping, and bevel milling operations. Drilling and tapping require the workpiece axis to coincide with the tool axis, and the workpiece must be in a vertically positioned state. However, in the bevel milling process, for fixed-position machine tools used for mass production of specialized nuts, the tool angle is fixed and cannot be adjusted to suit the bevel machining requirements. Therefore, the only way to achieve high-precision bevel milling is to adjust the workpiece's own tilt angle so that the bevel is perpendicular to the fixed vertical milling cutter axis.

[0003] Existing methods for machining beveled nuts typically employ a multi-stage, distributed machining approach. However, this approach involves multiple clamping operations, which can easily lead to accumulated positioning errors. It's difficult to guarantee the coaxiality of the threaded bottom hole and the outer circle, as well as the angular accuracy between the bevel and the thread axis. Some existing technologies use rotary multi-station drilling and tapping combination machines to complete the drilling and tapping processes. However, the workpiece clamping mechanism of these machines is fixed in a vertical position, making it impossible to achieve the workpiece tilting required for bevel milling. The workpiece still needs to be transferred to a milling machine for separate bevel machining, failing to achieve true one-time clamping and full-process combination machining. A search of existing published patent CN201910130032.6 reveals an adjustable-angle machining positioning fixture structure that uses a motor gear transmission angle adjustment mode. It relies on the self-locking of the transmission mechanism and the motor brake to achieve angle limiting, but does not have an independent mechanical rigid locking structure. In actual machining operations, the existing patented structures of this type involve continuous alternating cutting loads and high-frequency cutting vibrations during drilling, tapping, and bevel milling. Relying solely on gear meshing self-locking and motor brake limiting cannot offset the micro-displacements of the structure caused by the cutting force. During machining, the workpiece is prone to angular deviation and slight wobbling, resulting in significant fluctuations in key dimensions such as bevel angle accuracy and thread bottom hole coaxiality. This leads to poor dimensional consistency in batch processing, making it difficult to meet the precision requirements for industrial mass production of bevel nuts. Meanwhile, existing high-precision machining solutions correspond to five-axis linkage CNC machining centers and related patented equipment. Although such equipment can achieve precise multi-angle attitude adjustment of the workpiece and ultra-high precision composite machining, the equipment purchase and maintenance costs are high, and the workpiece clamping and tool switching processes are cumbersome, resulting in long single-workpiece machining cycles. These solutions are only suitable for small-batch, multi-variety, and customized ultra-high precision nut machining scenarios. Summary of the Invention

[0004] The present invention provides a bevel nut machining fixture and a machining process thereof, which solves the technical problems in the related art that fixed multi-station drilling and tapping machine tools cannot adjust the inclination angle of workpieces, simple tilting fixtures have poor positioning and locking rigidity and unstable precision, five-axis equipment has high cost and low mass production efficiency, and integrated machining of adaptive workpiece posture switching and rigid locking cannot be realized under the working condition of fixed tool inclination angle.

[0005] The present invention provides a bevel nut machining fixture, comprising a frame base and a console arranged on the frame base, a machining groove is arranged at the top of the frame base, an indexing rotation mechanism is arranged at the center of the machining groove, an indexing plate is fixed at the top of the indexing rotation mechanism, a plurality of machining mechanisms are arranged circumferentially on the periphery of the indexing plate, a plurality of tilting clamping mechanisms are arranged at equal intervals circumferentially on the top edge of the indexing plate, and a positioning and locking mechanism is arranged on one side of the tilting clamping mechanism.

[0006] A plurality of mounting grooves are arranged at equal intervals circumferentially on the top surface of the indexing plate, and T-shaped grooves are symmetrically arranged on the bottom surfaces of the mounting grooves.

[0007] The tilting clamping mechanism comprises a clamping base, a clamping block, a tilting shaft, an elastic collet, a collet control member and a tilting driving member. The clamping base is fixed in the mounting groove, a rotating groove is arranged at the top of the clamping base, the lower end of the clamping block is fixedly connected with the tilting shaft, both ends of the tilting shaft are rotatably connected to the inner side surface of the rotating groove, the elastic collet is mounted on the top of the clamping block, the collet control member is arranged at the bottom of the elastic collet, and the tilting driving member is fixedly connected with one end of the tilting shaft.

[0008] The positioning and locking mechanism comprises two locking cylinders, a fixed back plate, an L-shaped fixed plate and a plug pin head, the two locking cylinders are mounted on the inner side of the fixed back plate, the fixed back plate is fixed on one side of the mounting groove through the L-shaped fixed plate, and the plug pin head is fixedly connected with the output end of the locking cylinder.

[0009] The tilting clamping mechanism is responsible for completing the precise switching between the vertical posture and the inclined machining posture of the workpiece and the centering and clamping of the workpiece; the positioning and locking mechanism is a supporting rigid locking structure for the tilting clamping mechanism. The tilting clamping mechanism can only realize angle adjustment and cannot withstand the continuous cutting loads of drilling, tapping and milling. If only the self-locking of the transmission structure is relied on, angle deviation and vibration deviation are very likely to occur; the positioning and locking mechanism adopts mechanical insertion for rigid locking, which can fix the adjusted tilting clamping mechanism, so that the cutting load is directly transmitted to the indexing plate base, cutting vibration is isolated, and machining precision and structural rigidity are guaranteed.

[0010] In a preferred embodiment, the bottom surface of the mounting groove is symmetrically provided with positioning holes, and the bottom surface of the clamping base is symmetrically provided with positioning protrusions. The positioning protrusions fit into the positioning holes. A T-bolt is provided in the T-slot, and the T-bolt passes through the clamping base and is locked by a nut. One side of the clamping block is provided with a vertical locking hole and an inclined locking hole. The vertical locking hole is used to engage with the insertion pin when the clamping block is vertically positioned, while the inclined locking hole is used to engage with the insertion pin when the clamping block is rotated and tilted.

[0011] In a preferred embodiment, the clamping block has a circular groove at the top, the elastic chuck is embedded in the circular groove, the bottom outer wall of the elastic chuck has a ring-shaped conical surface, the side wall of the elastic chuck has three ring-shaped expansion and contraction slots evenly distributed along the axial direction, and the bottom of the elastic chuck is connected to a micro motor for controlling the rotation of the elastic chuck and tilting the cut nut at different positions of the inclined surface.

[0012] In a preferred embodiment, the chuck control component includes a cylinder, a control rod, a rotary bearing, and a top plate. A through-hole is provided on one side of the clamping block, and the control rod is fitted into the through-hole and slides vertically. The control rod extends into the circular groove, with one end connected to the rotary bearing and the other end connected to the cylinder output end. The cylinder is fixed above the through-hole by the top plate, and the rotary bearing is nested on the outer side of the ring clamp's conical surface.

[0013] In a preferred embodiment, the tilting drive includes a drive servo motor, a drive shaft, a drive gear, a driven gear, and an encoder. The driven gear is fixed to one end of the tilting shaft, the encoder is connected to the other end of the tilting shaft via a coupling, the encoder is electrically connected to a control console, the driven gear meshes with the drive gear, the drive gear is mounted on the output end of the drive servo motor, and the drive servo motor is mounted on one side of the mounting slot.

[0014] In a preferred embodiment, the indexing rotation mechanism includes an indexing housing, a servo motor, a reducer, a turntable spindle, and a support bearing. The indexing housing is a cylindrical structure and is fixed at the center of the machining groove. The support bearing is fitted inside the indexing housing, and the servo motor is fixed inside the machining groove. The output end of the servo motor passes through the support bearing and connects to the bottom surface of the indexing plate.

[0015] In a preferred embodiment, the machining mechanism includes a support base, a feed back plate, a feed slide, a feed motor, a screw, a feed hanger, and a workpiece. The support base is fixed around the indexing plate, the feed back plate is fixed to the top of the support base, and the feed slide has a threaded sleeve on its inner side. One end of the screw is connected to the output end of the feed motor, and the other end is fitted with the threaded sleeve and rotates helically. The feed motor is fixed to the top of the feed back plate, one side of the feed slide abuts against the edge of the feed back plate and slides in engagement, and the feed hanger is fixed to the outer side of the feed slide.

[0016] In a preferred embodiment, the workpiece includes a rotary motor, sprockets, a chain, a clamping housing, a machining shaft, and a clamping head. The rotary motor is fixed to the feed plate. The sprockets are symmetrically arranged, with a chain nested around the outer side of each sprocket and engaging for transmission. The output end of the rotary motor is connected to one of the sprockets, and the other sprocket is fixedly connected to the machining shaft. The clamping housing is fixed to the feed plate, and the machining shaft is located inside the clamping housing. The clamping head is threadedly engaged with the clamping housing. Drilling, tapping, and beveling tools are mounted on the end of the machining shaft via a flat key.

[0017] A process for machining beveled nuts, applied to the above-mentioned tooling, includes the following steps: Step 1: Tooling initialization and parameter setting. According to the specifications and angle of the inclined nut to be processed, set the indexing angle of the indexing rotary mechanism, the feed parameters and cutting parameters of each processing mechanism in the control panel, set the tilt angle of the tilting drive, calibrate the zero reference of the tilting shaft through encoder feedback, and replace the elastic chuck that matches the outer circle of the nut blank. Step 2: Loading and clamping. Place the hexagonal nut blank into the elastic chuck at the loading station. The cylinder of the chuck control component is activated, pushing the control rod to slide upward along the through-hole. The rotating bearing at the end of the control rod presses upward against the ring-shaped conical surface at the bottom of the elastic chuck. Under the action of the conical surface, the elastic chuck radially contracts along the three ring-shaped expansion and contraction seams, thus centering and clamping the nut blank. Step 3: Indexing and Drilling. The servo motor of the indexing rotation mechanism is reduced in speed by the reducer and drives the turntable spindle and indexing plate to rotate at a set angle. The tilting clamping mechanism that clamps the workpiece is rotated to the drilling position. At this time, the clamping block is in a vertical state. The locking cylinder of the positioning and locking mechanism drives the plug pin to insert into the vertical locking hole on the side of the clamping block to achieve rigid locking. The machining mechanism of the drilling position is started. The rotating motor drives the machining shaft through the sprocket and chain to drive the drill bit to rotate. The feed motor drives the screw to rotate. The screw drives the feed slide to feed vertically along the feed back plate through the threaded sleeve. The threaded bottom hole is drilled in the center of the nut blank. Step 4: Tapping. The indexing plate rotates again to the set angle, and the workpiece is moved to the tapping station. The clamping block remains vertical, and the insertion pin is inserted into the vertical locking hole to lock it. The machining mechanism of the tapping station is started. The rotating motor drives the machining shaft through the sprocket and chain to rotate the tap. The feed motor drives the feed slide to feed vertically. The feed amount is synchronized with the tap pitch. The internal thread is tapped in the bottom hole of the thread. After tapping to the set depth, the rotating motor reverses and the feed slide rises synchronously to remove the tap. Step 5: Inclined milling. The indexing plate rotates again to the set angle, and the workpiece is moved to the inclined milling station. The locking cylinder of the positioning and locking mechanism drives the insertion pin to exit from the vertical locking hole. The drive servo motor of the inclined drive component starts and drives the inclined shaft to rotate through the drive gear and driven gear. The inclined shaft drives the clamping block, elastic chuck and workpiece to rotate around the inclined shaft axis to the set inclined angle. The encoder detects the rotation angle of the inclined shaft in real time and feeds it back to the control console. After the set angle is reached, the drive servo motor stops. The locking cylinder drives the insertion pin to insert into the inclined locking hole on the side of the clamping block to achieve rigid locking. The machining mechanism of the inclined milling station starts. The rotation motor drives the machining shaft to rotate through the sprocket and chain, and the feed motor drives the feed slide to feed vertically, milling an inclined surface of the set angle on the end face of the nut. Step 6: Unloading. After the inclined milling is completed, the insert pin head exits from the inclined locking hole. The servo motor drives the inclined shaft in the opposite direction to drive the clamping block back to the vertical state. The indexing plate rotates again to the set angle. The workpiece is moved to the unloading station. The cylinder of the chuck control component is reset. The control rod slides down. The rotating bearing loosens the ring clamp cone surface. The elastic chuck opens under its own elasticity. The finished inclined nut is removed. Step 7: Continuous cycle processing. Loading, drilling, tapping, bevel milling and unloading operations are performed simultaneously at multiple stations on the indexing plate. Each time an indexing rotation is completed, each station completes one process synchronously. The tilting drive and positioning locking mechanism work together to achieve precise switching and rigid positioning of the workpiece between vertical and tilted states, realizing continuous automated processing of the bevel nut.

[0018] The beneficial effects of this invention are as follows: 1. This invention utilizes the coordinated operation of a tilting clamping mechanism and a positioning locking mechanism to address mass production machining scenarios where the tool tilt angle is fixed and only the workpiece posture can be adjusted. The tilting clamping mechanism enables precise switching between the workpiece's vertical machining posture and its inclined surface machining posture. The positioning locking mechanism, with its insert pins inserted into vertical and inclined locking holes respectively, achieves rigid mechanical locking throughout the entire process. Compared to traditional simple tooling relying on motor brakes and gear self-locking for limiting, this invention directly bears the cutting load during machining, effectively preventing workpiece angular deviation and micro-vibration during processing. It achieves the goal of completing all machining processes—drilling, tapping, and inclined milling of inclined nuts—in a single clamping setup, eliminating accumulated errors from multiple clamping and positioning operations and significantly improving the dimensional consistency of batch machining.

[0019] 2. This invention uses an encoder on the tilt drive component to detect the tilt axis rotation angle in real time and feed it back to the control console, thus forming a closed-loop angle control. This eliminates the need to replace angle shims or readjust the vise, significantly improving machining efficiency. Compared to existing five-axis CNC machining centers, this dedicated fixture has the advantages of simple structure, low cost, and fast machining cycle time. It is suitable for the industrial mass production needs of large quantities of single-type inclined nuts, while simultaneously balancing machining accuracy and production efficiency. Attached Figure Description

[0020] Figure 1 This is an overall structural diagram of the present invention.

[0021] Figure 2 This is a partial component structure diagram of the present invention.

[0022] Figure 3 This is a structural diagram of the indexing rotation mechanism of the present invention.

[0023] Figure 4 This is a structural diagram of the indexing plate of the present invention.

[0024] Figure 5 This is a structural diagram of the processing mechanism of the present invention.

[0025] Figure 6 This is a breakdown diagram of the processing mechanism of the present invention.

[0026] Figure 7 This is a structural diagram of the tiltable clamping mechanism of the present invention.

[0027] Figure 8 This is a structural diagram of the clamping base of the present invention.

[0028] Figure 9 This is a structural diagram of the clamping block of the present invention.

[0029] Figure 10 This is a structural diagram of the chuck control component of the present invention.

[0030] Figure 11 This is a structural diagram of the tilting drive component of the present invention.

[0031] Figure 12 This is a structural diagram of the positioning and locking mechanism of the present invention.

[0032] In the diagram: 1. Frame base; 11. Machining slot; 2. Control console; 3. Indexing rotary mechanism; 31. Indexing housing; 32. Servo motor; 33. Reducer; 34. Turntable spindle; 35. Support bearing; 4. Indexing plate; 41. Mounting slot; 411. Positioning hole; 42. T-slot; 421. T-bolt; 5. Machining mechanism; 51. Support base; 52. Feed back plate; 53. Feed slide; 531. Threaded sleeve; 54. Feed motor; 55. Screw; 56. Feed hanging plate; 57. Rotary motor; 58. Sprocket; 581. Chain; 59. Clamping housing; 591. Machining shaft; 592. Clamping head; 6. Tilting clamping mechanism; 61. Clamping base; 611 612. Rotating groove; 62. Positioning protrusion; 63. Clamping block; 64. Vertical locking hole; 65. Inclined locking hole; 66. Circular groove; 67. Through opening; 68. Inclined shaft; 69. Elastic chuck; 60. Ring clamp conical surface; 61. Ring clamp expansion joint; 62. Micro motor; 63. Chuck control component; 64. Cylinder; 65. Control rod; 66. Rotating bearing; 66. Top plate; 67. Inclined drive component; 68. Drive servo motor; 69. Drive shaft; 60. Drive gear; 61. Driven gear; 62. Encoder; 79. Positioning and locking mechanism; 70. Locking cylinder; 71. Fixed back plate; 72. L-shaped fixed plate; 73. Insertion pin. Detailed Implementation

[0033] The present application will now be described in further detail with reference to the accompanying drawings. It should be noted that the following specific embodiments are only used to further illustrate the present application and should not be construed as limiting the scope of protection of the present application. Those skilled in the art can make some non-essential improvements and adjustments to the present application based on the above application content. Example

[0034] like Figures 1 to 3 As shown, a tooling for machining beveled nuts includes a frame base 1 and a control console 2 mounted on the frame base 1. The top of the frame base 1 has a machining groove 11, which is a circular recess for accommodating an indexing rotation mechanism 3 and a machining mechanism 5. The control console 2 is PLC-controlled and equipped with a touch screen for parameter setting, status display, and fault alarms, and is mounted on one side of the frame base 1.

[0035] A dividing rotary mechanism 3 is provided at the center of the machining slot 11. A dividing plate 4 is fixed on the top of the dividing rotary mechanism 3. Five machining mechanisms 5 are arranged around the outer periphery of the dividing plate 4, corresponding to the loading station, drilling station, tapping station, inclined milling station and unloading station respectively. The central angle between adjacent machining mechanisms 5 is 72°. Five sets of tilting clamping mechanisms 6 are equidistantly arranged around the top edge of the dividing plate 4. Each set of tilting clamping mechanisms 6 corresponds to one station. A positioning locking mechanism 7 is provided on one side of the tilting clamping mechanism 6.

[0036] like Figure 3 As shown, the indexing rotation mechanism 3 includes an indexing housing 31, a servo motor 32, a reducer 33, a turntable spindle 34, and a support bearing 35. The indexing housing 31 is a cylindrical structure, fixed at the center of the machining groove 11, and fastened to the machine frame base 1 by hexagonal bolts. The support bearing 35 is a tapered roller bearing, fitted into the bearing hole inside the indexing housing 31. The servo motor 32 is fixed on a motor mounting plate inside the machining groove 11. The reducer 33 is a planetary gear reducer, with the output end of the servo motor 32 connected to the input end of the reducer 33, and the output end of the reducer 33 connected to the lower end of the turntable spindle 34 via a flexible coupling. The turntable spindle 34 is vertically arranged, with its upper end connected to the indexing plate 4 via a flat key and a round nut. After being reduced in speed by the reducer 33, the servo motor 32 drives the indexing plate 4 to rotate intermittently in 72° steps. The servo motor 32 has a brake function; after indexing, the brake locks in place to prevent the indexing plate 4 from shifting under cutting force.

[0037] like Figure 2 and Figure 4 As shown, the top surface of the indexing plate 4 has five mounting slots 41 equidistantly spaced around its circumference. Each mounting slot 41 is a rectangular groove used to mount the tilting clamping mechanism 6. The bottom surface of each mounting slot 41 has two symmetrically arranged positioning holes 411 for positioning the tilting clamping mechanism 6. The bottom surface of each mounting slot 41 also has two symmetrically arranged T-slots 42. T-bolts 421 are installed within each T-slot 42, passing through the clamping base 61 and being locked in place with nuts, thus securing the tilting clamping mechanism 6 within the mounting slots 41.

[0038] like Figures 7 to 9 As shown, the tilting clamping mechanism 6 includes a clamping base 61, a clamping block 62, a tilting shaft 63, an elastic chuck 64, a chuck control component 65, and a tilting drive component 66.

[0039] The clamping base 61 has a cuboid structure with two symmetrical positioning protrusions 612 on the bottom. The positioning protrusions 612 fit into the positioning holes 411 on the bottom surface of the mounting groove 41 to achieve radial positioning. The clamping base 61 is then fastened in the mounting groove 41 by T-bolts 421 passing through the T-slots 42. The top of the clamping base 61 has a rotating groove 611, which is a U-shaped opening groove used to accommodate the lower end of the clamping block 62 and the tilting shaft 63.

[0040] The clamping block 62 is made of alloy and has a rectangular structure. Its lower end is hinged to the rotating groove 611 on the top of the clamping base 61 via an inclined shaft 63. The top of the clamping block 62 has a circular groove 623 for mounting the elastic chuck 64. One side of the clamping block 62 has a vertical locking hole 621 and an inclined locking hole 622. The center of the vertical locking hole 621 coincides with the axis of the insertion pin 74 when the clamping block 62 is in a vertical position. The center of the inclined locking hole 622 coincides with the axis of the insertion pin 74 after the clamping block 62 has been rotated and tilted by 30°. The other side of the clamping block 62 has a through-hole 624, which is a vertically elongated through hole for controlling the up-and-down sliding of the control rod 652.

[0041] The tilting shaft 63 is mounted at both ends in the shaft holes on both sides of the rotating groove 611 via bearings. The bearings are 6204 deep groove ball bearings, ensuring flexible rotation of the tilting shaft 63. The tilting shaft 63 is connected to the lower end of the clamping block 62 to achieve synchronous swinging. The swing center of the tilting shaft 63 coincides with the center of the end face of the nut blank held by the elastic chuck 64, ensuring that the center position of the nut end face remains unchanged when the clamping block 62 swings, only the angle changes.

[0042] like Figure 10 As shown, the elastic chuck 64 is cylindrical with a hexagonal inner hole that mates with the outer circle of the hexagonal nut blank. The bottom outer wall of the elastic chuck 64 has a ring-shaped conical surface 641. Three ring-shaped expansion and contraction slots 642 are evenly distributed axially along the side wall of the elastic chuck 64, extending from the front end face to the rear end face, dividing the front end of the chuck into three elastic claws. A micro motor 643, a DC geared motor, is connected to the bottom of the elastic chuck 64. The micro motor 643 is fixed inside the clamping block 62, and its output shaft is connected to the bottom of the elastic chuck 64 via a coupling. This micro motor controls the low-speed rotation of the elastic chuck 64, enabling the tilting and cutting of the nut's inclined surface at different positions.

[0043] The chuck control component 65 includes a cylinder 651, a control rod 652, a rotary bearing 653, and a top plate 654. The cylinder 651 is fixed above the through-hole 624 on one side of the clamping block 62 via the top plate 654. The top plate 654 is an L-shaped plate made of 45# steel and is fixed to the top side of the clamping block 62 with bolts. The control rod 652 is made of 45# steel, fitted into the through-hole 624 and sliding up and down. The upper end of the control rod 652 extends into the circular groove 623, and the lower end is connected to the piston rod of the cylinder 651 via a floating joint. The rotary bearing 653 is nested in the upper end of the control rod 652, and the outer circumferential surface of the rotary bearing 653 contacts the outer side of the ring-shaped conical surface 641 at the bottom of the elastic chuck 64. When the piston rod of cylinder 651 extends upward, it pushes the control rod 652 to slide upward along the through-hole 624. The rotating bearing 653 at the end of the control rod 652 presses upward against the ring clamp conical surface 641. The force of the conical surface causes the elastic chuck 64 to contract radially along the three ring clamp expansion and contraction seams 642, centering and clamping the nut blank. When the piston rod of cylinder 651 retracts, the control rod 652 slides downward, the rotating bearing 653 releases the ring clamp conical surface 641, and the elastic chuck 64 opens under its own elasticity, releasing the workpiece. The rotating bearing 653 is nested on the outside of the ring clamp conical surface 641. When the elastic chuck 64 rotates under the drive of the micro motor 643, the rotating bearing 653 rotates accordingly without affecting the rotation of the chuck.

[0044] like Figure 11 As shown, the tilting drive 66 includes a drive servo motor 661, a drive shaft 662, a drive gear 663, a driven gear 664, and an encoder 665. The drive servo motor 661 is fixed to one side of the mounting slot 41 by a motor bracket. One end of the drive shaft 662 is connected to the output end of the drive servo motor 661 via a flexible coupling, and the other end is fitted with the drive gear 663. The driven gear 664 is fixed to one end of the tilting shaft 63 and meshes with the drive gear 663 for transmission. The drive servo motor 661 drives the tilting shaft 63 to rotate after the gear pair reduces speed. The encoder 665 is a 17-bit absolute rotary encoder, connected to the other end of the tilting shaft 63 via a coupling. The encoder 665 is electrically connected to the control console 2, which detects the rotation angle of the tilting shaft 63 in real time and feeds it back to the control console 2, forming a closed-loop angle control.

[0045] like Figure 12As shown, the positioning and locking mechanism 7 includes locking cylinders 71, a fixed back plate 72, an L-shaped fixing plate 73, and a pin head 74. Two locking cylinders 71 are installed inside the fixed back plate 72. The fixed back plate 72 is a rectangular plate made of 45# steel. The L-shaped fixing plate 73 is an L-shaped angle plate made of 45# steel. The fixed back plate 72 is fixed to one side of the mounting groove 41 by bolts, so that the output shafts of the two locking cylinders 71 are aligned with the vertical locking hole 621 and the inclined locking hole 622 on the side of the clamping block 62, respectively. The pin head 74 has a guide cone at its head and is threadedly connected to the front end of the piston rod of the locking cylinder 71. When the clamping block 62 is in a vertical state, the upper locking cylinder 71 drives the pin head 74 to insert into the vertical locking hole 621 to achieve rigid locking; when the clamping block 62 rotates and tilts to a set angle, the lower locking cylinder 71 drives the pin head 74 to insert into the inclined locking hole 622 to achieve rigid locking. This structure employs a dual-station plug-in locking mechanism, corresponding to two machining states: vertical drilling and tapping, and tilt milling. It solves the problems of tilting clamping mechanisms lacking mechanical limits after angle adjustment and the transmission structure being susceptible to deformation and wobbling under cutting forces. The two mechanisms work together to achieve precise angle adjustment and rigid locking, improving the overall machining rigidity and precision stability of the equipment. During locking, the cutting force is directly transmitted to the clamping base 61 and indexing plate 4 through the plug-in pin 74. The tilting shaft 63 and gear pair do not bear the cutting load, significantly improving system rigidity and component lifespan during machining.

[0046] like Figure 5 and Figure 6 As shown, machining mechanism 5 includes a support base 51, a feed back plate 52, a feed slide 53, a feed motor 54, a screw 55, a feed lifting plate 56, and a workpiece. The three machining mechanisms 5 have the same structure, only differing in the cutting tools mounted on the end of the machining shaft 591, which are a drill bit, a tap, and a face milling cutter, respectively.

[0047] The support base 51 is bolted to the frame base 1 surrounding the indexing plate 4. The feed back plate 52 is a vertical plate made of 45# steel and is bolted to the top of the support base 51. Two parallel linear guide rails are provided on the inner side of the feed back plate 52. The feed slide 53 is made of 45# steel and has a slider on its inner side that cooperates with the linear guide rails, allowing it to slide vertically along the feed back plate 52. A threaded sleeve 531 is provided in the middle of the inner side of the feed slide 53. The threaded sleeve 531 is made of copper alloy and has a trapezoidal internal thread.

[0048] The feed motor 54 is an AC servo motor, bolted to the top of the feed back plate 52. One end of the screw 55 is connected to the output end of the feed motor 54 via a flexible coupling, and the other end is fitted into a threaded sleeve 531, engaging with it in a helical rotational fit. When the feed motor 54 drives the screw 55 to rotate, the screw 55 drives the feed slide 53 to feed vertically along the feed back plate 52 via the threaded sleeve 531. The feed hanger 56 is bolted to the outside of the feed slide 53 and moves synchronously with the feed slide 53.

[0049] The workpiece includes a rotary motor 57, sprockets 58, a chain 581, a clamping housing 59, a machining shaft 591, and a clamping head 592. The rotary motor 57 is a three-phase asynchronous motor, fixed to the feed hanger 56 via a motor mount. Two sprockets 58 are symmetrically arranged; one sprocket 58 is fixed to the output shaft of the rotary motor 57, and the other sprocket 58 is fixed to the upper end of the machining shaft 591. The chain 581 is nested outside the two sprockets 58 and engages for transmission, driving the machining shaft 591 to rotate via the sprocket and chain drive from the rotary motor 57. The clamping housing 59 is a cylindrical housing made of 45# steel, bolted to the bottom of the feed hanger 56. The machining shaft 591 is located inside the clamping housing 59, supported at both ends by angular contact ball bearings. The clamping head 592 engages with the internal thread at the lower end of the clamping housing 59 to lock the tool. The machining shaft 591 has drilling, tapping and beveling tools installed at its end via a flat key. The drilling station is equipped with a high-performance cobalt high-speed steel twist drill, the tapping station is equipped with a spiral groove tap, and the beveling milling station is equipped with an indexable end mill.

[0050] The working principle of the tilting clamping mechanism 6 in this embodiment is as follows: the drive servo motor 661 of the tilting drive component 66 starts, and drives the tilting shaft 63 to rotate via the drive gear 663 and the driven gear 664. The tilting shaft 63 drives the clamping block 62, the elastic chuck 64, and the workpiece to rotate around the axis of the tilting shaft 63. The encoder 665 detects the rotation angle of the tilting shaft 63 in real time and feeds it back to the control console 2. When the rotation angle reaches the set value, the control console 2 controls the drive servo motor 661 to stop. At this time, the tilting locking hole 622 on the side of the clamping block 62 is aligned with the insertion pin 74 below the positioning locking mechanism 7. The locking cylinder 71 drives the insertion pin 74 to insert into the tilting locking hole 622 to achieve rigid locking. When it is necessary to return to the vertical position, the locking cylinder 71 drives the plug pin 74 to exit the tilting locking hole 622, drives the servo motor 661 to drive the tilting shaft 63 to rotate in the opposite direction, and the encoder 665 stops after detecting the zero position. The upper locking cylinder 71 drives the plug pin 74 to insert into the vertical locking hole 621 to achieve rigid locking in the vertical position.

[0051] The clamping principle of the elastic chuck 64 is as follows: the piston rod of the cylinder 651 extends upward, pushing the control rod 652 to slide upward along the through-hole 624. The rotating bearing 653 at the end of the control rod 652 presses upward against the ring-shaped conical surface 641 at the bottom of the elastic chuck 64. Due to the taper of the ring-shaped conical surface 641, the radial component of the force exerted by the rotating bearing 653 on the ring-shaped conical surface 641 causes the elastic chuck 64 to contract radially along the three ring-shaped expansion and contraction seams 642, reducing the size of the hexagonal inner hole and centering and clamping the hexagonal nut blank. When releasing the workpiece, the piston rod of the cylinder 651 retracts, the control rod 652 slides downward, the rotating bearing 653 releases the ring-shaped conical surface 641, and the elastic chuck 64 opens under its own elasticity, the hexagonal inner hole returns to its original shape, and the workpiece is released. When it is necessary to tilt the nut at different positions of the inclined surface, the micro motor 643 drives the elastic chuck 64 to rotate at low speed, and the rotating bearing 653 rotates accordingly without affecting the rotation of the chuck, thereby realizing the cutting of the inclined surface at different positions.

[0052] The machining process for the beveled nut in this embodiment includes the following steps: Step 1: Tooling Initialization and Parameter Setting. Based on the specifications of the hexagonal beveled nut to be machined, set the indexing angle of the indexing rotary mechanism 3 to 72° and the indexing delay to 0.5 seconds on the touchscreen of control console 2. Set the drilling parameters, tapping parameters, and milling parameters. Set the tilt angle of the tilting drive component 66 to 30°. Start the drive servo motor 661. Use the encoder 665 to calibrate the zero-position reference of the tilting shaft 63, ensuring the encoder reading is zero in the vertical position.

[0053] Step 2: Loading and Clamping. Place the hexagonal nut blank into the elastic chuck 64 at the loading station, ensuring the bottom surface of the nut blank is flush with the bottom surface of the circular groove 623. The cylinder 651 of the chuck control component 65 actuates, extending the piston rod upwards and pushing the control rod 652 upwards along the through-hole 624. The rotating bearing 653 at the end of the control rod 652 presses upwards against the ring-shaped conical surface 641 at the bottom of the elastic chuck 64. Under the radial force of the conical surface 641, the elastic chuck 64 radially contracts along the three ring-shaped expansion and contraction seams 642, reducing the size of the hexagonal inner hole and centering and clamping the hexagonal nut blank. At this time, the clamping block 62 is in a vertical position. The locking cylinder 71 above the positioning and locking mechanism 7 drives the insertion pin 74 to insert into the vertical locking hole 621 on the side of the clamping block 62 to achieve rigid locking.

[0054] Step 3: Indexing and Drilling. The servo motor 32 of the indexing rotation mechanism 3 starts, and after being reduced in speed by the reducer 33, drives the turntable spindle 34 and the indexing plate 4 to rotate 72°, transferring the tilting clamping mechanism 6, which clamps the workpiece, from the loading station to the drilling station. After indexing, the servo motor 32 engages the brake and locks the workpiece, while the insertion pin 74 remains rigidly locked in the vertical locking hole 621. The machining mechanism 5 at the drilling station starts. The rotary motor 57 drives the machining shaft 591 to rotate via the sprocket 58 and chain 581. The feed motor 54 drives the screw 55 to rotate, and the screw 55, via the threaded sleeve 531, drives the feed slide 53 to feed vertically along the feed back plate 52, drilling a threaded hole in the center of the nut blank. After drilling is completed, the feed motor 54 reverses, the feed slide 53 quickly retracts, and the rotary motor 57 stops.

[0055] Step 4: Tapping. The indexing plate 4 rotates 72° again, and the workpiece is transferred from the drilling station to the tapping station. The clamping block 62 remains vertical, and the insertion pin 74 is inserted into the vertical locking hole 621 to lock it in place. The machining mechanism 5 of the tapping station starts, and the rotary motor 57 drives the machining shaft 591 to rotate via a sprocket and chain. The feed motor 54 drives the feed slide 53 to feed vertically, tapping the internal thread in the threaded hole. After tapping to the set depth, the rotary motor 57 reverses, and the feed slide 53 rises synchronously to remove the tap. Then the rotary motor 57 stops.

[0056] Step 5: Inclined Milling. The indexing plate 4 rotates 72° again, and the workpiece is transferred from the tapping station to the inclined milling station. The locking cylinder 71 above the positioning and locking mechanism 7 drives the insertion pin 74 to exit from the vertical locking hole 621, releasing the vertical locking. The drive servo motor 661 of the tilting drive component 66 starts, driving the tilting shaft 63 to rotate via the drive gear 663 and the driven gear 664. The tilting shaft 63 drives the clamping block 62, the elastic chuck 64, and the workpiece to rotate around the axis of the tilting shaft 63. The encoder 665 detects the rotation angle of the tilting shaft 63 in real time and feeds it back to the control console 2. When the rotation angle reaches 30°, the control console 2 controls the drive servo motor 661 to stop. At this time, the inclined locking hole 622 on the side of the clamping block 62 is aligned with the insertion pin 74 below. The locking cylinder 71 drives the insertion pin 74 to insert into the inclined locking hole 622 to achieve rigid locking. The machining mechanism 5 of the inclined milling station starts, and the rotary motor 57 drives the machining shaft 591 to rotate via a sprocket and chain, thereby rotating the face milling cutter. The feed motor 54 drives the feed slide 53 to feed vertically, milling a 30° inclined surface on the upper end face of the nut. After milling is completed, the feed slide 53 retracts, and the rotary motor 57 stops.

[0057] Step Six: Unloading. After the inclined milling is completed, the locking cylinder 71 drives the insertion pin 74 to exit from the inclined locking hole 622, releasing the inclined locking. The servo motor 661 drives the inclined shaft 63 to rotate in the reverse direction. The encoder 665 stops after detecting the zero position, and the clamping block 62 returns to the vertical state. The upper locking cylinder 71 drives the insertion pin 74 to insert into the vertical locking hole 621 to achieve vertical locking. The indexing plate 4 rotates 72° again, and the workpiece is moved to the unloading station. The cylinder 651 of the chuck control component 65 resets, the piston rod retracts, the control rod 652 slides downward, the rotating bearing 653 releases the ring clamp conical surface 641, and the elastic chuck 64 opens under its own elasticity. The operator or robot arm removes the machined inclined nut from the elastic chuck 64.

[0058] Step 7: Continuous Cyclic Machining. Loading, drilling, tapping, bevel milling, and unloading operations are performed simultaneously at the five stations of the indexing plate 4. Each 72° indexing rotation completes one process at each station. The tilting drive 66, in conjunction with the positioning and locking mechanism 7, enables precise switching and rigid positioning of the workpiece between vertical and tilted states, requiring no manual intervention and achieving continuous automated machining of the bevel nut.

[0059] The embodiments described above are merely examples of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention.

Claims

1. A tooling for machining beveled nuts, comprising a frame base (1) and a control console (2) mounted on the frame base (1), wherein the top of the frame base (1) is provided with a machining groove (11), the center of the machining groove (11) is provided with an indexing rotation mechanism (3), the top of the indexing rotation mechanism (3) is fixed with an indexing plate (4), and the periphery of the indexing plate (4) is provided with a plurality of machining mechanisms (5), characterized in that, The indexing plate (4) has several tilting clamping mechanisms (6) equidistantly arranged around its top edge, and a positioning locking mechanism (7) is provided on one side of each tilting clamping mechanism (6). The indexing plate (4) has several mounting grooves (41) equidistantly spaced on its top surface, and the bottom surface of the mounting grooves (41) is symmetrically provided with T-shaped grooves (42). The tiltable clamping mechanism (6) includes a clamping base (61), a clamping block (62), a tilting shaft (63), an elastic chuck (64), a chuck control component (65), and a tilting drive component (66). The clamping base (61) is fixed in the mounting groove (41). The top of the clamping base (61) is provided with a rotating groove (611). The lower end of the clamping block (62) is fixedly connected to the tilting shaft (63). The two ends of the tilting shaft (63) are rotatably connected to the inner side of the rotating groove (611). The elastic chuck (64) is installed on the top of the clamping block (62). The chuck control component (65) is located at the bottom of the elastic chuck (64). The tilting drive component (66) is fixedly connected to one end of the tilting shaft (63). The positioning and locking mechanism (7) includes a locking cylinder (71), a fixed back plate (72), an L-shaped fixed plate (73), and a plug pin (74). There are two locking cylinders (71), which are installed inside the fixed back plate (72). The fixed back plate (72) is fixed to one side of the mounting groove (41) by the L-shaped fixed plate (73). The plug pin (74) is fixedly connected to the output end of the locking cylinder (71).

2. The tooling for machining beveled nuts according to claim 1, characterized in that, The mounting groove (41) has a symmetrically arranged positioning hole (411) on its bottom surface, and the clamping base (61) has a symmetrically arranged positioning protrusion (612) on its bottom surface. The positioning protrusion (612) fits into the positioning hole (411). The T-slot (42) has a T-bolt (421) inside it. The clamping block (62) has a vertical locking hole (621) and an inclined locking hole (622) on one side.

3. The tooling for machining beveled nuts according to claim 2, characterized in that, The clamping block (62) has a circular groove (623) at the top, and the elastic chuck (64) is embedded in the circular groove (623). The bottom outer wall of the elastic chuck (64) has a ring clamping cone surface (641). The side wall of the elastic chuck (64) has three ring clamping expansion and contraction slots (642) evenly distributed along the axial direction. The bottom of the elastic chuck (64) is connected to a micro motor (643).

4. The tooling for machining beveled nuts according to claim 3, characterized in that, The clamp control component (65) includes a cylinder (651), a control rod (652), a rotating bearing (653), and a top plate (654). The clamping block (62) has a through-hole (624) on one side. The control rod (652) fits into the through-hole (624) and slides up and down. The control rod (652) extends into the circular groove (623). One end of the control rod (652) is connected to the rotating bearing (653), and the other end is connected to the output end of the cylinder (651). The cylinder (651) is fixed above the through-hole (624) by the top plate (654). The rotating bearing (653) is nested on the outside of the ring clamp cone surface (641).

5. The tooling for machining beveled nuts according to claim 4, characterized in that, The tilting drive (66) includes a drive servo motor (661), a drive shaft (662), a drive gear (663), a driven gear (664), and an encoder (665). The driven gear (664) is fixed at one end of the tilting shaft (63), and the encoder (665) is connected to the other end of the tilting shaft (63) via a coupling. The encoder (665) is electrically connected to the control console (2). The driven gear (664) meshes with the drive gear (663). The drive gear (663) is installed at the output end of the drive servo motor (661), and the drive servo motor (661) is installed on one side of the mounting slot (41).

6. The tooling for machining beveled nuts according to claim 5, characterized in that, The indexing rotation mechanism (3) includes an indexing housing (31), a servo motor (32), a reducer (33), a turntable spindle (34), and a support bearing (35). The indexing housing (31) is a cylindrical structure and is fixed at the center of the machining groove (11). The support bearing (35) is fitted inside the indexing housing (31). The servo motor (32) is fixed inside the machining groove (11). The output end of the servo motor (32) passes through the support bearing (35) and connects to the bottom surface of the indexing plate (4).

7. The tooling for machining beveled nuts according to claim 6, characterized in that, The processing mechanism (5) includes a support base (51), a feed back plate (52), a feed slide (53), a feed motor (54), a screw (55), a feed lifting plate (56), and a workpiece. The support base (51) is fixed around the indexing plate (4), the feed back plate (52) is fixed on the top of the support base (51), and the feed slide (53) is provided with a threaded sleeve (531) on its inner side.

8. The tooling for machining beveled nuts according to claim 7, characterized in that, One end of the screw (55) is connected to the output end of the feed motor (54), and the other end is fitted with a threaded sleeve (531) and rotates in a spiral manner. The feed motor (54) is fixed on the top of the feed back plate (52). One side of the feed slide (53) abuts against the edge of the feed back plate (52) and slides in a sliding manner. The feed hanging plate (56) is fixed on the outside of the feed slide (53).

9. The tooling for machining beveled nuts according to claim 8, characterized in that, The workpiece includes a rotary motor (57), a sprocket (58), a chain (581), a clamping housing (59), a machining shaft (591), and a clamping head (592). The rotary motor (57) is fixed on the feed plate (56). The sprockets (58) are symmetrically arranged, and the chain (581) is nested on the outside of the sprockets (58) and engaged for transmission. The output end of the rotary motor (57) is connected to one of the sprockets (58), and the other sprocket (58) is fixedly connected to the machining shaft (591). The clamping housing (59) is fixed on the feed plate (56), and the machining shaft (591) is located inside the clamping housing (59). The clamping head (592) is threadedly engaged with the clamping housing (59). Drilling, tapping, and bevel milling tools are installed at the end of the machining shaft (591) via a flat key.

10. A machining process for a beveled nut machining fixture as described in claim 9, characterized in that, Includes the following steps: Step 1: Tooling initialization and parameter setting. According to the specifications and angle of the inclined nut to be processed, set the indexing angle of the indexing rotation mechanism (3), the feed parameters and cutting parameters of each processing mechanism (5) in the control console (2), set the tilt angle of the tilting drive (66), calibrate the zero position reference of the tilting shaft (63) through the encoder (665), and replace the elastic chuck (64) that matches the outer circle of the nut blank. Step 2, loading and clamping: The hexagonal nut blank is placed into the elastic chuck (64) at the loading station. The cylinder (651) of the chuck control component (65) is activated, pushing the control rod (652) to slide upward along the through-hole (624). The rotating bearing (653) at the end of the control rod (652) presses upward against the ring clamping cone surface (641) at the bottom of the elastic chuck (64). Under the action of the cone surface, the elastic chuck (64) contracts radially along the three ring clamping expansion and contraction seams (642) to center and clamp the nut blank. Step 3: Indexing and Drilling. The servo motor (32) of the indexing rotary mechanism (3) is reduced in speed by the reducer (33) and drives the turntable spindle (34) and the indexing plate (4) to rotate at a set angle, turning the tilting clamping mechanism (6) that clamps the workpiece to the drilling position. At this time, the clamping block (62) is in a vertical state. The locking cylinder (71) of the positioning locking mechanism (7) drives the insertion pin head (74) to insert into the side of the clamping block (62). The vertical locking hole (621) achieves rigid locking. The machining mechanism (5) of the drilling station is started. The rotating motor (57) drives the machining shaft (591) to rotate the drill bit via the sprocket (58) and chain (581). The feed motor (54) drives the screw (55) to rotate. The screw (55) drives the feed slide (53) to feed vertically along the feed back plate (52) via the threaded sleeve (531). The threaded bottom hole is drilled in the center of the nut blank. Step 4: Tapping. The indexing plate (4) rotates again to the set angle, and the workpiece is moved to the tapping station. The clamping block (62) remains vertical. The insertion pin (74) is inserted into the vertical locking hole (621) to lock. The processing mechanism (5) of the tapping station is started. The rotating motor (57) drives the processing shaft (591) through the sprocket chain to rotate the tap. The feed motor (54) drives the feed slide (53) to feed vertically. The feed amount is synchronized with the tap pitch. The internal thread is tapped in the bottom hole of the thread. After tapping to the set depth, the rotating motor (57) reverses and the feed slide (53) rises synchronously to remove the tap. Step 5: Inclined milling. The indexing plate (4) rotates again to the set angle, and the workpiece is moved to the inclined milling station. The locking cylinder (71) of the positioning locking mechanism (7) drives the insertion pin (74) to exit from the vertical locking hole (621). The drive servo motor (661) of the inclined drive component (66) starts, and drives the inclined shaft (63) to rotate through the drive gear (663) and the driven gear (664). The inclined shaft (63) drives the clamping block (62), the elastic chuck (64), and the workpiece to rotate around the axis of the inclined shaft (63) to the set inclined angle. The encoder... (665) Real-time detection of the rotation angle of the tilting shaft (63) and feedback to the control console (2). After reaching the set angle, drive the servo motor (661) to stop. The locking cylinder (71) drives the plug pin head (74) to insert into the tilting locking hole (622) on the side of the clamping block (62) to achieve rigid locking. The machining mechanism (5) of the inclined milling station starts. The rotating motor (57) drives the machining shaft (591) through the sprocket chain to drive the face milling cutter to rotate. The feed motor (54) drives the feed slide (53) to feed vertically and mill an inclined surface with a set angle on the end face of the nut. Step 6: Unloading. After the inclined milling is completed, the insert pin (74) exits from the inclined locking hole (622), and the drive servo motor (661) drives the inclined shaft (63) in the opposite direction to drive the clamping block (62) back to the vertical state. The indexing plate (4) rotates again to the set angle, and the workpiece is moved to the unloading station. The cylinder (651) of the chuck control component (65) is reset, the control rod (652) slides down, the rotating bearing (653) loosens the ring clamp cone surface (641), and the elastic chuck (64) opens under its own elasticity. The finished inclined nut is removed. Step 7: Continuous cycle processing. Loading, drilling, tapping, inclined milling and unloading operations are performed simultaneously at multiple stations on the indexing plate (4). Each time an indexing rotation is completed, each station completes one process synchronously. The tilting drive (66) and the positioning locking mechanism (7) work together to achieve precise switching and rigid positioning of the workpiece between the vertical and tilted states, thereby realizing the continuous automated processing of the inclined nut.

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