CNC Automatic Horizontal Drilling Machine

EQUIPPED WITH
4 horizontal drilling spindles
2 milling machines for pockets
2 horizontal milling machines for slot, stopped slot, prolonged slot, kerf, rebated kerf (with shaped wheel), QM (bevel cut)
The machine features:
2 slab conveyors with manually adjusted width for processing slabs of different sizes. Alongside each conveyor there is a guide to keep the slab aligned
4 drilling units, 2 on each side of the machine, which can travel along the whole length of the machine
2 cutting units for the pocket placed above two drilling units on each side of the machine
2 cutting units for slot/kerf placed above two drilling units on each side of the machine
2 mechanical stops to hold the slab in position during processing.
Work cycle
Processing occurs when the slab is not moving. The two conveyors move the slab to the mechanical stops. Before reaching them, speed is reduced to allow for smooth, precise positioning.
Then, drilling and pocket cutting are performed, or slots and kerfs are made. Once processing is over, the slab is moved backwards, the two mechanical stops retract, and the conveyors bring the slab to the discharge point.
A new slab is placed on the conveyors, and cycle is started again.
Machine specifications:
Slab max width: 180 cm
Slab min width: 25 cm
Max distance between 2 holes: 190 cm
Min distance between 2 holes without milling machine: 18 cm
Min distance between 2 holes with milling machine: 23 cm
Handling
Spindle handilng along the whole length of the machine and of the two carts is operated along precision guides by means of recirculating ball slide guides.
Motion is operated by precision rolled screws with recirculating ball bushes and precision gearboxes. The four spindles and the two carts are operated by brushless motors coupled with precision gearboxes and driven by electronic drivers which are in turn CNC-operated.
Precision in positioning
Precision in positioning is lower than +/- 0.2 mm.
Output
Depending on the material used (marble, tender or hard granite) the typical hole with 6-8 mm diameter and 25-30 mm depth is completed in 20-30 seconds. The distance between two slabs is about 20 cm which entails a motion time of about 20 seconds. Therefore, 4 holes are completed in 40-50 seconds, with an output of 290-360 holes per hour. The average repositioning time is about 5 seconds.
Lubrication
Lubrication of moving parts is centralized and automated. An automated lubrication cycle for periods when the machine is not used is also available.
Positioning system
It is automated thanks to an industrial computer. The operator must set slab width, hole position with reference to the mechanical stops, make requests for holes with or without pocket, and the automatic system will provide the necessary motions for the drilling heads and the carts.
Once the machine is positioned, the automated work cycle is started.
The height of the drilling spindles is adjusted by using a motor-reducer operated by two buttons on the spindle columns.
4 holes on each side of the slab can be made, along with two pockets on one side, as well as slots, prolonged slots, and kerfs.
The computer features also the following utilities:
Generation of drilling programs, storing of the programs by code (brand), list of and changes to the programs (on the machine) sorted by order
Generation of drilling programs, storing of the programs by code (brand), list of and changes to the programs on PC so that they can be later stored in the machine by using a floppy disc, and sorted by order
Displaying of drilling programs
Displaying of machine status (diagnostics)
Automatic synchronising
Storing and displaying of drilled slabs and of the holes made as of a given date (password required) Lubrication cycles for periods when the machine is not used.

Parameters	Unit	DRILLING UNIT	HOLE POCKET UNIT	SLOT/KERF UNIT
Cutting Groove Diameter	mm	-	200	200
Speed adjustment (cont.)		Hydraulic brake for 1/2	Gearbox for 1, 2, and 3	Gearbox for 1 and 2
Max. working thickness	mm	-	-	6
Pocket position		-	Along the vertical axis of the hole	-
Max. stroke	mm	80	-	-
Speed	mm/min	Slow fwd (1)Fast fwd 2) Fast rtn (3)	Slow fwd (1)Fast fwd 2) Fast rtn (3)	Fast fwd (1) Fast rtn (2)
Stroke adjustment		Mechanical with backing devices; electronic with magnetic sensors	Mechanical with backing devices; electronic with magnetic sensors	Mechanical with backing devices; electronic with magnetic sensors
Characteristics		Holed axis for point cooling, pneumatic operating with hydraulic brake	Pneumatic operating with hydraulic brake	Pneumatic operating with gearbox
Rotation speed	r/min	5600	2800	2800
Total motor power	kw	1.1	2.2	3.7