JPH0160382B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is a device for automatically adjusting the fluctuation of the center of gravity when an attachment is attached to the ram of the spindle head of a machine tool, particularly a bed-mounted transverse slicing boring machine.

In floor-mounted horizontal milling machines, machining is often carried out by attaching an attachment to the ram, and since the attachment generally has a considerable weight, the position of the center of gravity of the spindle head changes by attaching it.
For this reason, when an attachment is attached, the center of gravity position is adjusted by changing the amount of balance according to its weight. However, since there are several types of attachments and their weights are not constant, it is necessary to set the balance amount depending on the weight each time they are attached. Recently, there has been a strong demand for automation from machine tool users, and in order to meet this demand, it has been desired to automatically attach and detach attachments and also automatically adjust the center of gravity.

The present invention has been made from this point of view, and its object is to generate a signal indicating the type of attachment and the fact that it has been attached when an attachment is attached to the ram, and to automatically adjust the center of gravity using this signal. The purpose of this invention is to provide an automatic center of gravity adjustment device.

A diagram showing an example will be described below. A spindle head 1 of a horizontal milling boring machine is guided in vertical movement by a column (not shown), and a balance weight 4 is attached above it via a wire 2 and a pulley 3 to balance the weight. A ram 5 movable laterally in the figure is inserted into the spindle head 1, and a tool or attachment (none of which is shown) is attached to the left end of the ram 5. The ram 5 is moved left and right by a servo motor 6, gears 7 and 8, and a ball screw 9. The right end of the ball screw 9 is connected to a potentiometer 12 via gears 10 and 11.

The movable terminals of the potentiometer 12 are connected to fixed resistors 13 of the same number as the types of attachments to be used.
14, 15, . . . and one side of the variable resistor 16 via a selection relay 17. These fixed resistors 13, 14, 15, ... and variable resistor 1
The other side of the amplifier 6 is connected to the input side of the amplifier 18 after all of them are connected, and the output side of the amplifier 18 is connected to the electromagnetic part of the electromagnetic relief valve 19. The discharge side of the pump 20 is connected to the electromagnetic relief valve 19, and is also connected to one side of a cylinder 22 fixed to the balance weight 4 via a pipe 21, and the other side of the cylinder 22 is connected to a tank 23. . The piston 24 in the cylinder 22 is connected to the wire 2 on one side, and the balance force is adjusted by changing the tension of the wire 2 on the one side according to the hydraulic pressure.

Next, the operation of the present invention will be explained. Since the amount of balance given to the head stock 1 by the ram 5 changes depending on its position, the position is given to the potentiometer 9 from the ball screw 9 via the gears 10 and 11. On the other hand, when an attachment is attached to the ram 5, the type of attachment is selected by attaching coded group dogs to different positions according to the type of attachment, and reading these dogs with a corresponding limit switch. This signal causes fixed resistance 1
3, 14, 15,... is selected by the selection relay 17, a voltage determined by the potentiometer 12 connected in series with the selected fixed resistance is applied to the amplifier 18, and the amplification is performed. After increasing the width with the pump 18, the electromagnetic relief valve 19 closes the pump 20.
control the discharge pressure. The discharge pressure of the pump 20 is applied to the upper side of the cylinder 22, and when the pressure is high, the tension in the wire 2 increases, that is, the headstock 1
The balance force on the left side of increases.

Note that the variable resistor 16 is the fixed resistor 13, 14, 15.
When using an attachment other than the attachment corresponding to..., the resistance corresponding to the weight is manually adjusted. Further, when cutting with a normal tool without using an attachment, an appropriate resistance value is set.

As described above, the present invention changes the position of the potentiometer according to the amount of movement of the ram, and
A fixed resistor selected depending on the type of attachment is added in series with this potentiometer to generate a voltage, which is amplified by an amplifier to control the electromagnetic relief valve. By adjusting the hydraulic pressure, the tension of the wire on one side was changed to adjust the balance amount. For this reason, the balance force is adjusted according to the amount of movement of the ram, and when an attachment is installed, it is automatically adjusted to achieve the appropriate balance according to the type of attachment used, resulting in efficient automated work. It provides machinery.

[Brief explanation of drawings]

The figure is a mechanical diagram showing an embodiment of the present invention. 1... Spindle head, 2... Wire, 4... Balance weight, 5... Ram, 9... Screw, 12... Potentiometer, 13, 14, 15... Fixed resistor, 18... Amplifier , 19...electromagnetic relief valve,
20...Pump, 22...Cylinder, 24...Piston.

Claims (1)

[Claims] 1 A spindle head that moves up and down, a ram that is inserted into the spindle head and moves in a direction perpendicular to the direction of movement of the spindle head and that attaches a tool or attachment to its tip, and a balance weight that balances the weight of the ram. and a potentiometer whose resistance is changed by a screw that moves the ram;
a fixed resistor connected in series to the potentiometer and selected according to the type of the plurality of attachments; an amplifier for amplifying the voltage input by the fixed resistor and the potentiometer; an electromagnetic relief valve that is controlled by the output of the pump and adjusts the discharge pressure of the pump; a cylinder that is operated by the discharge pressure of the pump and is attached to one side of the balance weight; and a wire that connects the piston in the cylinder and the headstock. Automatic adjustment device for the center of gravity of the spindle head.