1. What is a gantry milling machine
A gantry milling machine is referred to as a gantry milling machine. It is a milling machine with a portal frame and a long horizontal bed. The gantry milling machine can use multiple milling cutters to machine the surface at the same time, and the machining accuracy and production efficiency are relatively high. It is suitable for machining the flat and inclined surfaces of large workpieces in batch and mass production. CNC gantry milling machines can also process space curved surfaces and some special parts.
Second, the structure of the gantry milling machine
The gantry milling machine consists of a portal frame, a bed worktable and an electrical control system.
The portal frame consists of uprights and top beams, with beams in the middle. The beam can move up and down along the guide rails of the two columns. There are 1-2 milling heads with vertical spindles on the beam, which can move laterally along the guide rail of the beam. A milling head with a horizontal spindle can also be installed on the two columns respectively, which can move up and down along the column guide rails. These milling heads can machine several surfaces simultaneously. Each milling head has a separate electric motor (power up to 150 kW), speed change mechanism, operating mechanism and spindle components.
The long horizontal bed has a movable work table and is covered with a protective cover. During processing, the workpiece is mounted on the worktable and then moves longitudinally.
The gantry milling machine also has some variants to adapt to different processing objects.
①Gantry boring and milling machine: the cross beam is equipped with a milling and boring head, its main shaft (sleeve or ram) can be used for axial motorized feed and has a motion fine-tuning device, the fine-tuning speed can be low to 5 mm/min. Boring and milling operations can be performed.
②Gantry drilling and milling machine: There is a power head on the beam, and the drill bit or milling cutter can be installed through the adaptor to complete the drilling and milling operations.
The X-axis guide rail is installed on the bed of the gantry milling machine, and the table of the gantry milling machine is fastened across the bed. A gantry frame is arranged on the movable spanning frame above the worktable, and the gantry frame also includes: a gantry frame carriage, and the gantry frame carriage is movably clamped on the X-axis guide rail. The Z-axis guide rail is installed on the gantry. The cross beam is provided with a Z-axis carriage, the cross beam is movably clamped on the Z-axis guide rail through the Z-axis carriage, and a Y-axis guide rail is also installed on the cross beam. Milling device, the milling device of the gantry milling machine is movably installed on the Y-axis guide rail, so that the gantry frame can perform three-dimensional space milling processing of X, Y, and Z axes under the control of the numerical control circuit control system. The CNC gantry milling machine has high-precision milling, drilling, boring, cutting and other operations.
Three, the performance characteristics of the gantry milling machine
The gantry milling machine has the characteristics of sufficient rigidity, high efficiency, convenient operation, simple structure and comprehensive performance. Its specific performance characteristics vary according to the type, model and manufacturer, and have a lot to do with the technology used. Taking SK series three-axis CNC gantry milling as an example, its performance characteristics are:
1. The vertical milling head is equipped with TX400 heavy-duty gantry milling head, double rectangular guide rails, and strong rigidity.
2. The milling head is equipped with a ball screw, a pneumatic broach device, and is driven by a servo motor.
3. The side milling head is equipped with a V5 type gantry milling head, and an independent lubricating device is installed.
4. One-click conversion of general milling/NC milling to three-axis CNC system, which can be programmed and operated manually by using the expansion panel, which is highly implementable in the actual machining process.
5. The advance and retreat of the bed, the upper and lower beams, and the upper and lower end milling heads are all equipped with Taiwan ball screws, which are driven by servo motors.
6. Equipped with synchronous belt and synchronous wheel.
7. Hand-held electronic handwheel unit, convenient for three-axis tool setting.
8. The unique safety interlocking device for lifting and lowering the beam ensures the repeated positioning accuracy of the machine tool.
9. Taiwan standard cycloid pump set is lubricated continuously, and the failure rate is low.
Fourth, gantry milling machine operating procedures
1. The work should be clamped with pressure plates, screws or special tools. Do not use a general wrench to add a casing, so as not to slip off and hurt people.
2. The tool must be clamped firmly, otherwise it is not allowed to drive.
3. Before working, it is necessary to check the operation of the transmission part of the machine tool, and install the baffle of the machine tool before it can run.
4. When milling various workpieces, especially rough milling, slow cutting should be performed at the beginning.
5. When moving the worktable and the tool rest, the fixing screws should be loosened first.
6. When loading and unloading knives, a copper hammer or a mallet should be used to lightly strike to prevent the knife fragments from flying out and hurting people.
7. During cutting, it is not allowed to change the speed and adjust the tool, and it is forbidden to touch or measure the workpiece by hand.
