A milling machine for processing ventilation holes of straight copper bars

Abstract

The utility model relates to processing machine tool technical field discloses a milling machine for linear copper bar vent hole processing, its characterized in that, including machine tool, be provided with three processing units on the machine tool, three processing units can independently along the length direction of machine tool removal, processing unit includes two milling heads, two milling heads can along the length direction of machine tool perpendicular horizontal removal synchronously, and two milling heads can independently carry out vertical removal and parallel to the length direction of machine tool removal, still be provided with workpiece fixture mechanism on the machine tool, workpiece fixture mechanism is used for positioning and clamping the copper bar of processing, processing unit still includes tool magazine system, tool magazine system is used for the automatic tool changing of milling head. The utility model has multiple independent control's processing unit, can realize the multi -hole synchronous high -efficient processing of long workpiece, and satisfies the requirement of high accuracy and small aperture processing.

Description

Technical Field

[0001] This utility model relates to the field of machine tool technology, and in particular to a milling machine for machining ventilation holes in straight copper busbars. Background Technology

[0002] In the field of large motor manufacturing, rotor coils are typically composed of long, straight copper busbars. To improve heat dissipation efficiency, numerous planar ventilation holes of varying sizes need to be machined on these busbars. These ventilation holes vary greatly in size (length 20mm–90mm, width 2.5mm–25mm) and require high machining accuracy (e.g., width error ≤ ±0.05mm). Especially for narrow, elongated holes less than 4mm wide, extremely high spindle speeds are required to achieve reasonable cutting linear speeds, which is difficult to meet with ordinary CNC milling machines.

[0003] Currently, the processing of such workpieces is mostly carried out step-by-step and piece-by-piece using general-purpose machine tools, which results in low production efficiency, cumbersome positioning and clamping, and poor consistency in machining accuracy. With the development of intelligent manufacturing, the processing of ventilation holes is being incorporated into the intelligent production line of rotor coils, creating an urgent need for a dedicated CNC milling machine capable of automatic clamping, simultaneous multi-hole processing, and high speed and precision. Utility Model Content

[0004] The purpose of this utility model is to provide a milling machine for machining ventilation holes in straight copper busbars, which has multiple independently controllable machining units, enabling simultaneous and efficient machining of multiple holes in long workpieces, and meeting the requirements of high precision and small hole diameter machining.

[0005] The above-mentioned technical objective of this utility model is achieved through the following technical solution: A milling machine for machining ventilation holes in straight copper busbars includes a machine tool with three machining units. Each machining unit can move independently along the length of the machine tool. Each machining unit includes two milling heads, which can move synchronously horizontally perpendicular to the length of the machine tool, and can also move independently vertically and parallel to the length of the machine tool. The machine tool also includes a workpiece clamping mechanism for positioning and clamping the copper busbar to be machined. The machining unit further includes a tool magazine system for automatically changing tools for the milling heads.

[0006] As a further feature of this invention, the machine tool includes a work base bed and a milling head bed arranged in parallel. The work base bed and the milling head bed are connected by bolts and locating pins, and mounting surfaces and bolt holes for extending the bed are reserved on the connecting end faces. The workpiece clamping mechanism is disposed on the work base bed. Multiple T-slots are provided on the upper surface and the front and rear sides of the work base bed for installing and adjusting the workpiece clamping mechanism. The machining unit is disposed on the milling head bed.

[0007] As a further feature of this invention, each of the machining units includes a sliding base, and a first longitudinal moving mechanism is provided between the sliding base and the milling head bed. The first longitudinal moving mechanism includes a first linear guide rail disposed between the sliding base and the machine tool and a first longitudinal driving component for driving the sliding base to move. The first linear guide rail is disposed along the length direction of the machine tool, and the first longitudinal driving component includes a rack disposed along the length direction of the machine tool, a gear meshing with the rack, and a motor for driving the gear to rotate.

[0008] As a further feature of this invention, an upper slide is provided on the lower slide, and a transverse moving mechanism is provided between the upper slide and the lower slide. The transverse moving mechanism includes a second linear guide rail and a transverse driving mechanism. The second linear guide rail is arranged along the length direction perpendicular to the machine tool, and the transverse driving mechanism includes a motor and a ball screw.

[0009] As a further feature of this invention, a column is fixedly mounted on the upper slide block, and two milling heads are mounted on the column. The tool magazine system is symmetrically distributed on both sides of the column and corresponds to each milling head.

[0010] As a further feature of this invention, the milling head includes a connecting block and a spindle portion. A third linear guide rail is provided on the side of the column along the length of the machine tool. The connecting blocks of the two milling heads are slidably mounted on the third linear guide rail. A second longitudinal drive assembly is provided on the column to drive the two connecting blocks to move independently along the linear guide rail. A fourth linear guide rail is provided on the connecting block. The fourth linear guide rail is vertically mounted. The spindle portion is slidably connected to the fourth linear guide rail. A vertical drive assembly is provided on the connecting block to drive the spindle portion thereon to move vertically.

[0011] As a further feature of this invention, the workpiece clamping mechanism includes a placement block, multiple independent pneumatic clamping units, a side-supporting unit, and several roller devices. The placement block is provided with a placement groove, which is an L-shaped groove. The L-shaped groove includes a bottom surface and a side surface. The bottom surface and side surface are positioned with the bottom surface and side surface of the copper busbar being processed as positioning references. The clamping unit and the side-supporting unit are located on the side of the machine tool opposite to the bottom surface and side surface of the placement groove, and can move along the length of the machine tool. A positioning block is provided on one side of the machine tool, and the multiple roller devices are liftable and adjustable to lift and transport the copper busbar so that it rests against the positioning block.

[0012] As a further feature of this invention, the copper busbar is divided into a front processing section and a rear processing section along its length. In the front processing section, the positioning side of the placement groove is close to the milling head, and in the rear processing section, the positioning side of the placement groove is far away from the milling head.

[0013] The beneficial effects of this utility model are: This invention provides a milling machine for machining ventilation holes on straight copper busbars. The machine features three independently movable machining units along its length, each integrating a dual-milling-head structure. This enables simultaneous or sequential, efficient machining of multiple ventilation holes on long copper busbars, significantly improving production efficiency. Addressing the challenges of machining small ventilation holes with high precision requirements, the milling head utilizes a high-speed electric spindle specifically designed for narrow holes. Simultaneously, the long-stroke motion mechanism employs a gear-rack and linear guide, ensuring both movement accuracy and system rigidity, thus meeting workpiece precision requirements.

[0014] The workpiece clamping mechanism integrates automatic conveying, pneumatic positioning and clamping, and in-situ detection functions, enabling rapid, accurate, and safe workpiece clamping. By setting positioning references in different areas and combining them with selectively operable clamping units, the spatial interference problem in machining the ventilation holes on both sides of the copper busbar is cleverly solved. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 This is a schematic diagram of the overall structure of this embodiment; Figure 2 yes Figure 1 Enlarged diagram of part A in the middle; Figure 3 This is a side view of the structure in this embodiment; In the figure, 1 is the machine tool, 11 is the work base bed, 12 is the milling head bed, 13 is the T-slot, 2 is the machining unit, 21 is the milling head, 22 is the lower slide, 23 is the first longitudinal moving mechanism, 24 is the upper slide, 25 is the transverse moving mechanism, 26 is the column, 27 is the connecting block, 28 is the spindle, 3 is the workpiece clamping mechanism, and 4 is the tool magazine system. Detailed Implementation

[0017] The technical solution of this utility model will now be clearly and completely described with reference to specific embodiments. Obviously, the described embodiments are only a part of the embodiments of this utility model, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without creative effort are within the scope of protection of this utility model.

[0018] A milling machine for machining ventilation holes in straight copper busbars includes a machine tool 1, three machining units 2, and a workpiece clamping mechanism 3.

[0019] Machine tool 1 adopts a parallel layout with two beds, including a work platform bed 11 specifically for mounting and fixing the workpiece clamping mechanism 3, and a parallel milling head bed 12 specifically for carrying and guiding the movement of the machining unit 2. Both beds are made of robust cast iron and are connected by a modular segmented design. The segments are precisely connected and rigidly joined by precision-machined locating surfaces, locating pins, and high-strength bolts. Standardized interfaces are reserved at the docking ends, allowing the total length of the bed to be flexibly extended according to future needs, providing good scalability.

[0020] The upper surface and front and rear sides of the work base bed 11 are machined with a series of T-slots 13, forming a multifunctional and adjustable installation reference surface. In particular, the middle T-slot 13 of the upper surface is set as the reference for installation and adjustment. All clamping elements can move flexibly and lock along the T-slot 13 to accommodate copper busbar workpieces of different lengths, widths and clamping positions.

[0021] The three machining units 2 are the core moving parts that perform cutting operations. They are structurally identical and independently mounted on the milling head bed 12. Each machining unit 2 includes a sliding base 22, which is connected to the milling head bed 12 via a high-rigidity first linear guide and driven by a first longitudinal drive assembly. The first longitudinal drive assembly includes an AC servo motor, a double gear, and a hardened helical rack. The AC servo motor drives the double gear, which meshes with the hardened helical rack mounted on the bed, enabling the entire unit to move longitudinally along the length of the machine tool 1 with a large stroke and high speed. This longitudinal movement uses a high-precision grating ruler that runs through the entire length of the bed for position feedback, achieving full closed-loop control and ensuring positioning accuracy and dynamic stability over long distances.

[0022] An upper slide 24 is provided on the lower slide 22. The two are connected by a transverse moving mechanism 25. The transverse moving mechanism 25 includes a second linear guide and a transverse driving mechanism. The transverse driving mechanism includes a motor and a ball screw. Specifically, a precision ball screw is driven by an independent servo motor to achieve transverse movement perpendicular to the longitudinal direction. This transverse movement adopts a fully closed-loop control and is responsible for the precise positioning of the milling head 21 in the workpiece width direction.

[0023] Each machining unit 2 has a column 26 fixed to an upper slide 24 at its top. Two completely independent vertical milling heads 21 are mounted side-by-side on the front of this column 26. Each milling head 21 has two independent axes of motion: one is a vertical feed motion driven by a servo motor and a ball screw; the other is a longitudinal fine-tuning motion driven by another servo motor and ball screw along a short guide rail on the side of the column 26, used to flexibly adjust the distance between the two milling heads 21 to accommodate different hole spacings. The core driving component of the milling head 21 is a built-in electric spindle with an ISO 30 taper bore and an automatic tool draw mechanism. The spindle is internally cooled by circulating water to maintain thermal stability under high-speed operation. To support continuous automated machining, two disc-type tool magazines are symmetrically installed on the left and right sides of each column 26, which can automatically change and store tools for the corresponding milling head 21.

[0024] Specifically, the milling head 21 includes a connecting block 27 and a spindle 28. A third linear guide is provided on the side of the column 26 along the length of the machine tool 1. The connecting blocks 27 of the two milling heads 21 are slidably mounted on the third linear guide. A second longitudinal drive assembly is provided on the column 26 to drive the two connecting blocks 27 to move independently along the linear guide. A fourth linear guide is provided on the connecting block 27. The fourth linear guide is vertically mounted. The spindle 28 is slidably connected to the fourth linear guide. A vertical drive assembly is provided on the connecting block 27 to drive the spindle 28 thereon to move vertically. Both the second longitudinal drive assembly and the vertical drive assembly are implemented by a servo motor driving a ball screw.

[0025] The workpiece clamping mechanism 3 is a key device to ensure accurate positioning and reliable clamping of the workpiece, and it is entirely mounted on the work base bed 11. The workpiece clamping mechanism 3 includes a placement block, multiple independent pneumatic clamping units, a side-lifting unit, several roller devices, and a fixed positioning block. The placement block is provided with a placement groove, which is an L-shaped groove. The L-shaped groove includes a bottom surface and a side surface, and the bottom surface and side surface are used as positioning references for the bottom surface and side surface of the copper busbar being processed.

[0026] Multiple independent pneumatic clamping units and pneumatic side-lifting units can be flexibly arranged and adjusted along the T-slot 13 of the work base bed 11. The roller device is height-adjustable and includes driving rollers and driven rollers. During operation, the copper busbar is first placed on the rollers of the roller device in the raised state; then, the driving roller driven by the motor smoothly transports the copper busbar until its end face is close to the fixed positioning block set on one side of the bed; next, multiple independent side-lifting units arranged along the length of the copper busbar act sequentially to push the side of the copper busbar against the positioning reference surface on the placement block; after the side positioning is completed, the roller device descends, and multiple independent pneumatic clamping units fall down to firmly clamp the copper busbar onto the work base bed 11.

[0027] To efficiently process the ventilation holes on both sides of the copper busbar, the copper busbar is divided into a front processing section and a rear processing section along its length. The two areas are set with mirrored positioning reference surfaces; that is, in the front processing section, the positioning side of the slot is close to the milling head 21, and in the rear processing section, the positioning side of the slot is away from the milling head 21. When processing one side of the ventilation hole, the CNC program intelligently controls the clamping unit and side-support unit, which may interfere with the milling cutter path, to remain stationary, automatically freeing up processing space, thus achieving interference-free automated operation for processing holes on both sides. All clamping and side-support units are equipped with position detection sensors to ensure that the machine tool 1 can only start the processing program after the system confirms that the clamping is in place, ensuring operational safety and processing reliability.

[0028] In terms of overall machine integration, the following key systems are also included: First, the CNC and electrical control system, whose core adopts the Siemens 840Dsl CNC system, equipped with three independent operating stations. Each operating station is equipped with a monitor with a mouse, a machine tool 1 operating panel, an electronic handwheel, and an emergency stop button. This system manages all logical actions through a built-in PLC and rationally distributes the three machining units 2 into multiple channels, which can realize centralized coordination and synchronous machining of the six milling heads 21, and also allow any one milling head 21 to operate independently.

[0029] Secondly, there is the chip removal and cooling system. The chip removal system adopts a comprehensive solution combining air blowing and dust extraction. Each milling head 21 machining area is equipped with a nearly enclosed protective cover, with air vents arranged around the perimeter inside the cover. Air is blown outwards to lift the fine copper chips generated during machining, and a dust extraction device concentrates the chip-laden airflow to the chip conveyor and chip collection carriage located in the middle of the machine bed. The cooling system consists of two parts: one is an internal circulating water cooling device for the electric spindle, with its water tank located on the back of the column 26, made of rust-proof and corrosion-resistant materials and equipped with a liquid level alarm function; the other is a cooling system for the cutting area, using alcohol cooling that directly acts on the contact point between the tool and the workpiece, effectively reducing temperature and minimizing the impact of cutting heat.

[0030] In addition, it includes an automatic lubrication and safety protection system. The lubrication of each moving part of the machine tool 1 (such as guideways and lead screws) is handled by multiple independent automatic lubricators. Each lubrication point has an independent oil tank, and an oil collection box is provided around the bed to recover excess lubricating oil and keep the work area clean. The protection system comprehensively covers the moving parts: the longitudinal and transverse movement areas of the milling head 21 use stainless steel telescopic protective covers, and the vertical movement area uses accordion-style protective covers, working in conjunction with the overall protective cover to effectively isolate the cutting area.

[0031] All clamping and side-top units are equipped with position detection sensors, which are interlocked with the CNC system to ensure that the machining cycle cannot start if the fixture is not confirmed to be clamped in place, thus ensuring operational safety from both hardware and software perspectives.

[0032] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A milling machine for machining ventilation holes in straight copper busbars, characterized in that, The machine tool (1) is provided with three processing units (2). Each of the three processing units (2) can move independently along the length of the machine tool (1). Each processing unit (2) includes two milling heads (21). The two milling heads (21) can move horizontally in a direction perpendicular to the length of the machine tool (1) at the same time. The two milling heads (21) can also move vertically and parallel to the length of the machine tool (1) independently. The machine tool (1) is also provided with a workpiece clamping mechanism (3). The workpiece clamping mechanism (3) is used to position and clamp the copper busbar to be processed. The processing unit (2) also includes a tool magazine system (4). The tool magazine system (4) is used to automatically change tools for the milling heads (21).

2. The milling machine for machining ventilation holes in straight copper busbars according to claim 1, characterized in that, The machine tool (1) includes a work base bed (11) and a milling head bed (12) arranged in parallel. The work base bed (11) and the milling head bed (12) are connected by bolts and positioning pins. The connection end face is reserved with mounting surface and bolt holes for extending the bed. The workpiece clamping mechanism (3) is set on the work base bed (11). The upper plane and front and rear sides of the work base bed (11) are provided with multiple T-shaped grooves (13) for installing and adjusting the workpiece clamping mechanism (3). The processing unit (2) is set on the milling head bed (12).

3. A milling machine for machining ventilation holes in straight copper busbars according to claim 2, characterized in that, Each of the processing units (2) includes a sliding base (22), and a first longitudinal moving mechanism (23) is provided between the sliding base (22) and the milling head bed (12). The first longitudinal moving mechanism (23) includes a first linear guide rail provided between the sliding base (22) and the machine tool (1) and a first longitudinal driving component for driving the sliding base (22) to move. The first linear guide rail is provided along the length direction of the machine tool (1), and the first longitudinal driving component includes a rack provided along the length direction of the machine tool (1), a gear meshing with the rack, and a motor for driving the gear to rotate.

4. A milling machine for machining ventilation holes in straight copper busbars according to claim 3, characterized in that, The lower slide (22) is provided with an upper slide (24), and a transverse moving mechanism (25) is provided between the upper slide (24) and the lower slide (22). The transverse moving mechanism (25) includes a second linear guide rail and a transverse driving mechanism. The second linear guide rail is arranged along the length direction perpendicular to the machine tool (1), and the transverse driving mechanism includes a motor and a ball screw.

5. A milling machine for machining ventilation holes in straight copper busbars according to claim 4, characterized in that, A column (26) is fixedly installed on the upper slide (24), and two milling heads (21) are installed on the column (26). The tool magazine system (4) is symmetrically distributed on both sides of the column (26) and corresponds to each milling head (21).

6. A milling machine for machining ventilation holes in straight copper busbars according to claim 5, characterized in that, The milling head (21) includes a connecting block (27) and a spindle (28). A third linear guide is provided on the side of the column (26) along the length of the machine tool (1). The connecting blocks (27) of the two milling heads (21) are slidably disposed on the third linear guide. A second longitudinal drive assembly is provided on the column (26) to drive the two connecting blocks (27) to move independently along the linear guide. A fourth linear guide is provided on the connecting block (27). The fourth linear guide is vertically disposed. The spindle (28) is slidably connected to the fourth linear guide. A vertical drive assembly is provided on the connecting block (27) to drive the spindle (28) thereon to move vertically.

7. A milling machine for machining ventilation holes in straight copper busbars according to claim 1, characterized in that, The workpiece clamping mechanism (3) includes a placement block, multiple independent pneumatic clamping units, a side-top unit, and several roller devices. The placement block is provided with a placement groove, which is an L-shaped groove. The L-shaped groove includes a bottom surface and a side surface. The bottom surface and the side surface are positioned with the bottom surface and the side surface of the copper busbar as the positioning reference. The clamping unit and the side-top unit are located on the side of the machine tool (1) opposite to the bottom surface and the side surface of the placement groove, and can move along the length of the machine tool (1). A positioning block is provided on one side of the machine tool (1). The multiple roller devices can be raised and lowered to lift and transport the copper busbar so that it rests against the positioning block.

8. A milling machine for machining ventilation holes in straight copper busbars according to claim 7, characterized in that, The copper busbar is divided into a front processing section and a rear processing section along its length. In the front processing section, the positioning side of the placement groove is close to the milling head (21), and in the rear processing section, the positioning side of the placement groove is far away from the milling head (21).

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