A drilling and milling composite CNC machine tool for machining automobile crankshafts

Abstract

This invention relates to the field of crankshaft machining technology and discloses a drilling and milling composite CNC machine tool for machining automotive crankshafts. The machine tool includes a base, on the top of which is fitted a clamping unit for limiting the crankshaft body. A mounting seat is also fixedly installed on the top of the base, and this mounting seat is equipped with a machining unit for drilling oblique oil holes in the crankshaft body via an adjusting mechanism on its top. A support assembly for supporting the crankshaft body is installed within the mounting seat, and the support assembly includes a movable groove formed within the mounting seat. This drilling and milling composite CNC machine tool for machining automotive crankshafts effectively solves the problem in the prior art where oblique oil holes are distributed in different axial sections of the crankshaft. When performing multi-station oil hole machining, frequent changes to the journal positions corresponding to the support mechanism are required, which increases the machining time of the crankshaft and thus affects the production efficiency of batch crankshaft machining.

Description

Technical Field

[0001] This invention relates to the field of crankshaft machining technology, and more specifically to a drilling and milling composite CNC machine tool for machining automobile crankshafts. Background Technology

[0002] The crankshaft is a core component of engine power output. The machining accuracy of its shaft directly determines the smoothness of engine operation, transmission efficiency and overall service life. Drilling and milling of the crankshaft's inclined oil holes are key precision processes. These processes have extremely high requirements for hole position tolerance, hole-shaft perpendicularity and hole wall surface quality. They are usually completed using composite CNC machine tools that integrate clamping, drilling and milling functions to reduce positioning errors caused by multiple clamping.

[0003] In the combined drilling and milling process of inclined oil holes, the cutting action of the tool induces multi-directional complex cutting loads on the shaft surface, which can easily cause flexural deformation and cutting chatter in the slender crankshaft, leading to machining defects such as hole position misalignment, hole diameter deviation, and deterioration of hole wall roughness. Therefore, during machining, auxiliary support mechanisms need to be added at the journals adjacent to the oil holes to be machined. These mechanisms constrain the radial and circumferential movement of the crankshaft in multiple dimensions to ensure the stability of the machining system. However, since the inclined oil holes are distributed in different axial sections of the crankshaft, frequent changes to the journal positions corresponding to the support mechanisms are necessary when performing multi-station oil hole machining. These adjustments to the support mechanism positions increase the crankshaft machining time, thus affecting the production efficiency of batch crankshaft machining. Summary of the Invention

[0004] To address the aforementioned shortcomings of existing technologies, this invention provides a drilling and milling composite CNC machine tool for machining automotive crankshafts. This tool effectively solves the problem in existing technologies where oblique oil holes are distributed across different axial sections of the crankshaft. When performing multi-station oil hole machining, it is necessary to frequently change the journal station corresponding to the support mechanism. Such adjustments to the position of the support mechanism increase the machining time of the crankshaft, thereby affecting the production efficiency of batch machining of crankshafts.

[0005] To achieve the above objectives, the present invention provides the following technical solution: This invention provides a drilling and milling composite CNC machine tool for machining automobile crankshafts, comprising: The base has a clamping unit for limiting the crankshaft body mounted on its top. The top of the base is also fixedly mounted with a mounting seat, and the mounting seat is equipped with a machining unit for opening oblique oil holes in the crankshaft body via an adjusting unit set on its top. The mounting base is equipped with a support assembly for supporting the crankshaft body. The support component includes a movable slot formed in the mounting base, and the movable slot has multiple slots arranged in an array along the central surface of the mounting base. The movable slot is equipped with a clamping block by a bearing shaft set inside it. The base is equipped with an abutment block by a lifting unit set on its top. The clamping block and the abutment block are respectively provided with V-shaped grooves inside. The mounting base is equipped with a switching unit on its outer side for adjusting the angle of the clamping block. When the switching unit contacts the clamping block, it drives the clamping block to rotate and separates the clamping block from the abutment block on the same side.

[0006] Furthermore, the mounting base has a slot that communicates with the movable groove, and a shaft that passes through the slot is rotatably mounted in the mounting base. A cam is fixedly mounted on the outer circumference of the shaft, and the number of cams corresponds one-to-one with the number of slots.

[0007] Furthermore, a drive motor is fixedly installed inside the mounting base, and a drive gear is fixedly installed at the output end of the drive motor, while a driven gear that meshes with the drive gear is fixedly installed at the end of the shaft.

[0008] Furthermore, a roller is fitted on the side of the clamping block away from the V-groove, and a torsion spring is fitted on the outer circumferential surface of the bearing shaft, and two torsion springs are provided and symmetrically distributed along the center plane of the bearing shaft.

[0009] Furthermore, the switching unit includes a fixed plate connected to the outside of the regulating unit, and an abutment plate is rotatably mounted on the bottom of the fixed plate. Two abutment plates are provided and symmetrically distributed along the center plane of the fixed plate, and a movable plate is hinged to the bottom of the abutment plate.

[0010] Furthermore, the switching unit also includes a rotary unit for driving one of the abutment plates to rotate; The rotary unit includes a transmission gear fixedly installed on the outside of one of the abutment plates. The fixed plate has a movable plate slidably installed on it via a guide groove provided on its outside. The movable plate is fitted with a rack that meshes with the transmission gear on its outside.

[0011] Furthermore, a fixing frame is fixedly installed on the outer side of the fixing plate, and a guide rod connected to the outer side of the moving plate is slidably installed inside the fixing frame. The guide rod is connected to the fixing frame through a return spring provided on its outer side.

[0012] Furthermore, a magnetic component is fixedly installed on the outer side of the fixing frame, and the magnetic component is connected to the moving plate by magnetic force.

[0013] The technical solution provided by this invention has the following advantages compared with the prior art: This invention features multiple sets of support components. Multiple independent support components are arranged in an array along the crankshaft axis of the machine tool. After the crankshaft is clamped, all journals are simultaneously held by corresponding clamping blocks and abutment blocks, providing multi-point rigid support for the entire crankshaft throughout the process. When the machining unit moves axially, the switching unit moves synchronously with the adjusting unit, applying a thrust only to the clamping block at the current machining station to deflect it away. The support constraints at other stations remain effective at all times, eliminating the need for overall movement and repositioning of the support mechanism, completely saving the auxiliary time for support repositioning. Furthermore, the support... The support avoidance and machining feed are seamlessly connected. The fixed plate of the switching unit is directly fixed to the moving part of the adjusting unit, maintaining axial synchronous displacement with the machining unit. When the machining unit feeds to the target station, the inclined abutment plate first contacts the clamping block, simultaneously triggering the corresponding support electromagnetic block to de-energize and unlock. As the feed continues to advance, the abutment plate pushes the clamping block to deflect and complete the avoidance. After the machining is completed, the unit moves away, and the clamping block automatically resets and re-electromagnetically locks under the action of the torsion spring, shortening the auxiliary time and improving the efficiency of crankshaft batch machining. Attached Figure Description

[0014] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are merely some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without any creative effort.

[0015] Figure 1 This is a three-dimensional structural diagram of an embodiment of the present invention; Figure 2 This is a three-dimensional structural diagram of the support component according to an embodiment of the present invention; Figure 3 This is a three-dimensional structural diagram of the shaft and cam according to an embodiment of the present invention; Figure 4 This is a cross-sectional view of the mounting base according to an embodiment of the present invention; Figure 5 This is an embodiment of the present invention. Figure 4 A magnified structural diagram of part A in the middle; Figure 6 This is a schematic diagram of the three-dimensional separation structure of the switching unit in an embodiment of the present invention; Figure 7 This is a schematic diagram of the three-dimensional transformation structure of the abutment plate according to an embodiment of the present invention; Figure 8 This is a cross-sectional planar structural diagram of the clamping block and the abutment block according to an embodiment of the present invention; Figure 9 This is a cross-sectional structural diagram of the crankshaft body according to an embodiment of the present invention.

[0016] The labels in the diagram represent: 100. Crankshaft body; 1. Base; 2. Clamping unit; 3. Mounting seat; 31. Slot; 32. Shaft; 33. Cam; 34. Drive motor; 35. Driving gear; 36. Driven gear; 4. Adjusting unit; 5. Machining unit; 6. Support assembly; 61. Movable slot; 62. Bearing shaft; 621. Torsion spring; 63. Clamping block; 631. Roller; 64. Abutment block; 65. V-groove; 66. Switching unit; 661. Fixed plate; 6611. Guide slot; 662. Abutment plate; 663. Movable plate; 664. Transmission gear; 665. Moving plate; 6651. Rack; 6652. Guide rod; 6653. Return spring; 666. Fixed frame; 6661. Magnetic component. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0018] The present invention will be further described below with reference to embodiments.

[0019] Example: Please see Figures 1-9 This invention provides a technical solution: a drilling and milling composite CNC machine tool for machining automobile crankshafts, comprising: The base 1 has a clamping unit 2 for limiting the crankshaft body 100 mounted on its top. The base 1 also has a mounting seat 3 fixedly mounted on its top. The mounting seat 3 is equipped with a processing unit 5 for opening oblique oil holes in the crankshaft body 100 via an adjustment unit 4 located on its top. The mounting base 3 is equipped with a support component 6 for supporting the crankshaft body 100. The support assembly 6 includes multiple movable slots 61 formed within the mounting base 3, arranged in an array along the central surface of the mounting base 3. Clamping blocks 63 are mounted on the movable slots 61 via bearing shafts 62 located within them. An abutment block 64 is mounted on the base 1 via a lifting unit located on its top. V-shaped grooves 65 are respectively formed inside the clamping blocks 63 and abutment blocks 64. The support assembly 6 adopts a separate design for the clamping blocks 63 and abutment blocks 64. When the clamping block 63 returns to its initial position under the action of the torsion spring 621, the lifting assembly pushes the abutment block 64 to close with the clamping block 63. At this time, the electromagnetic blocks inside the abutment block 64 and clamping block 63 are energized, generating a strong magnetic attraction force, causing the two to rigidly adhere as a whole. The V-shaped grooves 65 inside both form a clamping space that precisely matches the outer wall of the journal. This structure not only restricts the crankshaft's vertical and horizontal movement in the radial direction, but also restricts its slight rotation in the circumferential direction, providing a highly rigid multidimensional constraint benchmark through the dual action of mechanical and electromagnetic mechanisms. The mounting base 3 is equipped with a switching unit 66 for adjusting the angle of the clamping block 63. When the switching unit 66 contacts the clamping block 63, it drives the clamping block 63 to rotate and separates the clamping block 63 from the abutment block 64 on the same side. The machine tool is arranged with multiple independent support components 6 in an array along the crankshaft axis. After the crankshaft is clamped, all journals are simultaneously clamped by the corresponding clamping blocks 63 and abutment blocks 64, providing multi-point rigid support for the entire crankshaft throughout the process. When the machining unit 5 moves axially, the switching unit 66 moves synchronously with the adjustment unit 4, applying a thrust only to the clamping block 63 of the current machining station to deflect it and avoid it. The support constraints of the other stations remain effective at all times. There is no need for overall movement or repositioning of the support mechanism, which completely eliminates the auxiliary time for support repositioning, realizes continuous processing, and helps to improve the batch processing efficiency of the crankshaft body 100.

[0020] The mounting base 3 has a slot 31 that communicates with the movable slot 61. A shaft 32 that passes through the slot 31 is rotatably mounted in the mounting base 3, and a cam 33 is fixedly mounted on the outer circumference of the shaft 32. The number of cams 33 and slots 31 are arranged in a one-to-one correspondence. The clamping block 63 has a degree of freedom of movement in the slot 31. When the clamping block 63 deflects upward around the central axis of the bearing shaft 62, its tail end rotates in the opposite direction around the central axis of the bearing shaft 62. At this time, the inner wall of the slot 31 does not mechanically limit the clamping block 63. When the clamping block 63 performs a reset action, its tail end deflects upward around the central axis of the bearing shaft 62 until the clamping block 63 returns to the initial position. At this time, the inner wall of the slot 31 forms a rigid block on the tail end of the clamping block 63, so that the clamping block 63 is locked in the initial position.

[0021] A drive motor 34 is also fixedly installed inside the mounting base 3, and a drive gear 35 is fixedly installed at the output end of the drive motor 34, and a driven gear 36 that meshes with the drive gear 35 is fixedly installed at the end of the shaft 32.

[0022] A roller 631 is mounted on the side of the clamping block 63 away from the V-groove 65, and a torsion spring 621 is mounted on the outer circumference of the bearing shaft 62. Two torsion springs 621 are provided and are symmetrically distributed along the center plane of the bearing shaft 62.

[0023] The switching unit 66 includes a fixed plate 661 connected to the outside of the regulating unit 4, and an abutment plate 662 is rotatably mounted on the bottom of the fixed plate 661. Two abutment plates 662 are provided and symmetrically distributed along the central plane of the fixed plate 661. A movable plate 663 is hinged to the bottom of the abutment plate 662. The switching unit 66 also includes a rotary unit for driving one of the abutment plates 662 to rotate. The rotary unit includes a transmission gear 664 fixedly mounted on the outside of one of the abutment plates 662. A movable plate 665 is slidably mounted on the fixed plate 661 via a guide groove 6611 on its outside. A rack 6651 meshing with the transmission gear 664 is fitted on the outside of the movable plate 665. A fixed frame 666 is fixedly mounted on the outside of the fixed plate 661, and a guide rod 6652 connected to the outside of the movable plate 665 is slidably mounted inside the fixed frame 666. The guide rod 6652 is connected to the fixed frame 666 via a return spring 6653 on its outside.

[0024] By setting a guide rod 6652 and a return spring 6653, one end of the return spring 6653 is connected to the guide and the other end is connected to the fixed frame 666. No matter whether the moving plate 665 moves forward or backward along the guide groove 6611, the return spring 6653 on the guide rod 6652 will produce elastic deformation. When the magnetic component 6661 stops working, the elastically deformed return spring 6653 will drive the moving plate 665 to return to the initial position, which is convenient for the processing of the next crankshaft body 100.

[0025] A magnetic component 6661 is fixedly installed on the outer side of the fixed frame 666, and the magnetic component 6661 is connected to the movable plate 665 by magnetic force. The magnetic component 6661 is an electromagnet, and a permanent magnet is provided on the movable plate 665. Since the polarity of the permanent magnet is constant, when the movable plate 665 needs to slide forward along the guide groove 6611, the magnetic component 6661 controls the direction of its internal current so that the magnetic component 6661 and the permanent magnet have opposite polarities, and thus they will attract each other. When the movable plate 665 needs to move in the opposite direction along the guide groove 6611, the direction of the internal current of the magnetic component 6661 changes, and the magnetic component 6661 and the permanent magnet have the same polarity. Thus, the force between the magnetic component 6661 and the movable plate 665 is a magnetic repulsion force, which can force the movable plate 665 to slide in the opposite direction along the guide groove 6611.

[0026] Working principle and advantages of the drilling and milling composite CNC machine tool used for machining automobile crankshaft body 100: Since the inclined oil holes on the crankshaft body 100 are distributed in different axial sections of the crankshaft body 100, when performing multi-station oil hole machining, it is necessary to frequently change the journal station corresponding to the support mechanism. Such position adjustment of the support mechanism will increase the machining time of the crankshaft body 100, thereby affecting the production efficiency of batch machining of the crankshaft body 100.

[0027] In the waiting state, the control system drives the drive motor 34 in the mounting base 3 to operate. The drive gear 35 at its output end rotates at a constant speed and drives the meshing driven gear 36, causing the shaft 32 to rotate around its own central axis. At the same time, the cam 33 fixedly mounted on the shaft 32 rotates accordingly. When its flange abuts against the bottom of the clamping block 63, the cam 33 applies a thrust to the clamping block 63. This thrust overcomes the elastic threshold of the torsion spring 621 on the bearing shaft 62, forcing the clamping block 63 to deflect into the slot 31 around the center line of the bearing shaft 62 to the limit position. At the same time, the lifting assembly drives the abutment block 64 to move down synchronously, so that the abutment block 64 and the clamping block 63 separate to the maximum gap. The external hoisting equipment moves the crankshaft body 100 to be processed into the base 1, and the crankshaft body 100 is limited and fixed by the three-jaw chuck in the clamping unit 2 in conjunction with the tailstock.

[0028] After the crankshaft body 100 is clamped, the drive motor 34 reverses, causing the cam 33 to rotate in the opposite direction via the gear transmission mechanism. The thrust of the cam 33 on the clamping block 63 gradually decreases, and under the elastic restoring force of the torsion spring 621, the clamping block 63 rotates in the opposite direction around the bearing shaft 62 to reset. During the reset process, the tail of the clamping block 63 is mechanically blocked by the inner wall of the slot 31 and positioned at the initial position, at which time its bottom remains parallel to the central axis of the crankshaft body 100. Subsequently, the lifting assembly drives the abutment block 64 to move upward and close with the clamping block 63. The electromagnetic blocks set inside both are energized to generate magnetic attraction force, making the clamping block 63 and the abutment block 64 rigidly attracted into a whole structure. The V-shaped grooves 65 on the inner walls of both form a clamping space that matches the main journal of the crankshaft body 100, thereby constraining the radial runout and circumferential micro-runout of the crankshaft body 100 in multiple dimensions, providing a stable reference for subsequent high-precision drilling and milling.

[0029] It is worth noting that both inner walls of the V-groove 65 are made of elastic material. The clamping block 63 and the abutment block 64 of this invention are separate. They are only attracted by electromagnetic force at the moment of closure. The electromagnetic attraction process allows the two V-grooves 65 to undergo a slight relative approach displacement. When the main journal is small due to the blank tolerance, the lifting component drives the abutment block 64 to move upward, and the two V-grooves 65 adaptively shrink the closing gap. If the shaft diameter is large, the closing angle is slightly larger. This "flexible closure and rigid locking" achieved by electromagnetic attraction ensures the high consistency of the machining reference of the inclined oil hole. In addition, the V-groove 65 itself has an automatic centering characteristic and can be adapted to crankshaft journals within a certain diameter range. With the height adjustment of the abutment block 64 lifting unit and the deflection allowance of the clamping block 63, it can be adapted to the machining of crankshafts of different specifications without replacing the support block.

[0030] During processing, the adjusting unit 4 drives the processing unit 5 to move. To prevent the clamping block 63 from obstructing the part to be processed, the switching unit 66 of the present invention is activated. In the rotary unit fixedly installed on the moving seat of the adjusting unit 4, the magnetic component 6661 is energized to generate magnetic attraction, attracting the moving plate 665 equipped with a permanent magnet to move along the guide groove 6611. The rack 6651 on the moving plate 665 drives the transmission gear 664 meshing with it to rotate, forcing the abutment plate 662 connected to the transmission gear 664 to deflect around the hinge point. Under the transmission of the linkage mechanism, the abutment plate 662 on the other side and the movable plate 663 move together, so that the rectangular frame mechanism composed of the fixed plate 661, the two abutment plates 662 and the movable plate 663 is deformed into a parallelogram structure, and the abutment plate 662 is in an inclined state.

[0031] When the processing unit 5 is fed, the rotary unit drives the rack 6651 and gear through magnetic attraction, causing the original rectangular frame to deform into a parallelogram. The bottom abutment plate 662 becomes tilted. As the unit moves forward, the tilted abutment plate 662 will precisely push the clamping block 63 at the corresponding station, avoiding rigid contact between the abutment plate 662 and the tail end of the clamping block 63 during the movement, which would hinder the normal movement of the processing unit 5.

[0032] When the machining unit 5 feeds to the first inclined oil hole machining station, the inclined abutment plate 662 first contacts the clamping block 63 at the station. At this time, the abutment block 64 and the electromagnetic block in the clamping block 63 are de-energized and released from attraction. As the machining unit 5 continues to feed, the inclined abutment plate 662 pushes the clamping block 63 to overcome the elastic force of the torsion spring 621 and deflect it again until the clamping block 63 slides along the inclined surface to the horizontal movable plate 663 and maintains the maximum deflection angle, thereby completely exposing the spindle journal at that location. Subsequently, the tool in the machining unit 5 completes the drilling and milling operation of the inclined oil hole at a preset angle.

[0033] It is worth noting that a roller 631 is installed at the contact position between the clamping block 63 and the abutment plate 662. When the inclined abutment plate 662 is fed by the assembly and pushes the clamping block 63, the two will slide relative to each other on the contact surface. If the surface-to-surface contact is used directly, it is a sliding friction pair with a large coefficient of friction. By adding a roller 631 at the contact point, the kinematic pair is transformed into a rolling friction pair. The coefficient of rolling friction is much smaller than the coefficient of sliding friction, which greatly reduces the tangential resistance. This allows the feeding thrust of the abutment plate 662 to be smoothly converted into an effective torque that deflects the clamping block 63, eliminating motion jerking.

[0034] After the processing at this station is completed, the processing unit 5 continues to move, the clamping block 63 disengages from the limit of the movable plate 663, and resets under the action of the torsion spring 621. The electromagnetic block is re-energized and clamps the crankshaft body 100. At the same time, the inclined abutment plate 662 contacts the next set of clamping blocks 63, repeating the above action cycle, thereby realizing the continuous processing of multi-station inclined oil holes.

[0035] Multiple sets of support components 6 are arrayed on the machine tool base 1. After the crankshaft is clamped, multiple sets of abutment blocks 64 and clamping blocks 63 together form all-round support for each main journal of the crankshaft through V-grooves 65. When the inclined oil hole in any section of the crankshaft needs to be machined, this set of support components 6 always maintains the limiting effect on the entire crankshaft. Since the support is multi-point parallel, wherever the tool moves, only local support avoidance is needed, which completely saves the time of overall support mechanism displacement, repositioning and locking.

[0036] After the crankshaft body 100 is processed, the operator stops the electromagnetic blocks of each set of clamping blocks 63 and abutment blocks 64 simultaneously. At this time, the drive motor 34 drives the drive gear 35 to rotate again, and together with the driven gear 36 and shaft 32, it can drive the cam 33 to act on the clamping block 63 again, so that the clamping block 63 is lifted upward synchronously until the clamping block 63 moves to the limit position. At the same time, the operator controls the lifting component to force the abutment block 64 to reset. After the clamping block 63 and the abutment block 64 are separated, the external hoisting equipment takes the processed crankshaft body 100 out of the clamping unit 2, and then places the next crankshaft body 100 to be processed into the clamping unit 2.

[0037] After all the inclined oil holes on the main journal of the crankshaft body 100 are machined, the magnetic component 6661 is de-energized, and the moving plate 665 is reset under the action of the return spring 6653, restoring the tilted abutment plate 662 to its initial horizontal state. For batch processing where the starting positions of adjacent workpieces alternate, this invention can change the current direction of the magnetic component 6661, converting the original magnetic attraction force into a magnetic repulsion force, driving the moving plate 665 to move in the opposite direction along the guide groove 6611, causing the abutment plate 662 to tilt and deflect in the opposite direction. Therefore, without needing to readjust the crankshaft body 100 or the overall machine tool support position, the next workpiece can be machined starting from the end position of the previous workpiece, significantly shortening the machining auxiliary time and greatly improving the batch production efficiency of the crankshaft body 100.

[0038] By changing the direction of the current input to the magnetic component 6661 through the control system, the magnetic component 6661 and the permanent magnet on the moving plate 665 can freely switch between "magnetic attraction" and "magnetic repulsion". When switching to magnetic repulsion, the moving plate 665 moves in the opposite direction along the guide groove 6611, driving the transmission gear 664 to rotate in the opposite direction, thereby causing the abutment plate 662 to tilt in the opposite direction. This gives the switching unit 66 a bidirectional avoidance function, allowing the machine tool to flexibly determine the direction of the starting point of the next workpiece based on the processing end point of the previous workpiece.

[0039] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions will not cause the essence of the corresponding technical solutions to deviate from the protection scope of the technical solutions of the embodiments of the present invention.

Claims

1. A drilling and milling composite CNC machine tool for machining automobile crankshafts, characterized in that, include: The base (1) is equipped with a clamping unit (2) for limiting the crankshaft body (100) on its top. The base (1) is also fixedly installed with a mounting seat (3), and the mounting seat (3) is equipped with a machining unit (5) for opening oblique oil holes in the crankshaft body (100) by means of an adjustment unit (4) set on its top. The mounting base (3) is equipped with a support component (6) for supporting the crankshaft body (100). The support component (6) includes a movable groove (61) opened in the mounting base (3), and the movable groove (61) is provided in multiple and arranged in an array along the center surface of the mounting base (3). The movable groove (61) is equipped with a clamping block (63) through a bearing shaft (62) set inside it. The base (1) is equipped with an abutment block (64) through a lifting unit set on its top. The clamping block (63) and the abutment block (64) are respectively provided with V-shaped grooves (65). The mounting base (3) is equipped with a switching unit (66) for adjusting the angle of the clamping block (63). When the switching unit (66) contacts the clamping block (63), it drives the clamping block (63) to rotate and separates the clamping block (63) from the abutment block (64) on the same side.

2. The drilling and milling composite CNC machine tool for machining automobile crankshafts according to claim 1, characterized in that: The mounting base (3) has a slot (31) that communicates with the movable slot (61). A shaft (32) that passes through the slot (31) is rotatably installed in the mounting base (3). A cam (33) is fixedly installed on the outer circumference of the shaft (32). The number of cams (33) and slots (31) are arranged in a one-to-one correspondence.

3. A drilling and milling composite CNC machine tool for machining automobile crankshafts according to claim 2, characterized in that: The mounting base (3) is also fixedly installed with a drive motor (34), and the output end of the drive motor (34) is fixedly installed with a drive gear (35), and the end of the shaft (32) is fixedly installed with a driven gear (36) that meshes with the drive gear (35).

4. A drilling and milling composite CNC machine tool for machining automobile crankshafts according to claim 1, characterized in that: The clamping block (63) is equipped with a roller (631) on the side away from the V-groove (65), and a torsion spring (621) is equipped on the outer circumferential surface of the bearing shaft (62), and the torsion spring (621) is provided in two and symmetrically distributed along the center plane of the bearing shaft (62).

5. A drilling and milling composite CNC machine tool for machining automobile crankshafts according to claim 1, characterized in that: The switching unit (66) includes a fixed plate (661) connected to the outside of the regulating unit (4), and an abutment plate (662) is rotatably mounted on the bottom of the fixed plate (661). The abutment plate (662) has two plates and is symmetrically distributed along the center plane of the fixed plate (661). A movable plate (663) is hinged to the bottom of the abutment plate (662).

6. A drilling and milling composite CNC machine tool for machining automobile crankshafts according to claim 5, characterized in that: The switching unit (66) also includes a rotary unit for driving one of the abutment plates (662) to rotate; The rotary unit includes a transmission gear (664) fixedly installed on the outside of one of the abutment plates (662). The fixed plate (661) has a movable plate (665) slidably installed on it through a guide groove (6611) on its outside. The movable plate (665) is fitted with a rack (6651) that meshes with the transmission gear (664) on its outside.

7. A drilling and milling composite CNC machine tool for machining automobile crankshafts according to claim 6, characterized in that: A fixing frame (666) is fixedly installed on the outside of the fixing plate (661), and a guide rod (6652) connected to the outside of the moving plate (665) is slidably installed inside the fixing frame (666). The guide rod (6652) is connected to the fixing frame (666) through a return spring (6653) provided on its outside.

8. A drilling and milling composite CNC machine tool for machining automobile crankshafts according to claim 7, characterized in that: A magnetic component (6661) is fixedly installed on the outside of the fixed frame (666), and the magnetic component (6661) is connected to the movable plate (665) by magnetic force.

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