JPS6042009Y2 - Machine tool feed control device - Google Patents

Description

[Detailed description of the invention] [Technical field] This invention relates to a feed control device for a machine tool such as a drilling machine, and particularly relates to an oil cylinder having a piston that moves integrally with a moving body of either a processing tool or a workpiece. The present invention relates to a feed control device for a machine tool that controls the feed speed of a moving body by adjusting the amount of oil discharged.

[Prior art]

Conventionally, as shown in FIG. 1, for example, in this type of device, a cylinder 4 is disposed on the outer periphery of a main shaft cylinder 2, and a piston 5 of the cylinder 4 is provided integrally with the main shaft cylinder 2. The forward moving side of 4 is an air chamber 4A, and the backward moving side is an oil chamber 4B. Furthermore, a pneumatic/hydraulic converter 12 is connected to the oil chamber 4B, and the converter 12
A parallel circuit including a throttle valve 11 and a check valve 13 is provided between the oil chamber 4B and the throttle valve 11, and a switching valve is provided in parallel with the throttle valve 11 and the check valve 13 for switching between rapid feed and cutting feed of the main spindle cylinder 2. 14 is provided, and when compressed air is supplied to the air chamber 4A side of the cylinder 4, most of the oil in the oil chamber 4B is moved forward through the switching valve 14 in fast forward motion, and then when the switching valve 14 is switched. , the oil chamber 4 only through the throttle valve 11
B oil is discharged into the converter 12 and the throttle valve 1
The forward movement of the main shaft cylinder 2 is controlled according to the discharge amount regulated by 1, and when the main shaft cylinder 2 moves backward, compressed air is supplied to the air chamber side of the pneumatic/hydraulic converter 12, and the converter 12 oil was supplied to the cylinder 4 through the check valve 13 and the piston 5 and the main shaft cylinder 2 were moved back.

However, in this case, compressed air is supplied into the converter 12 so that the main shaft cylinder 2 returns to its original position, and the oil pressure in the oil chamber 4b of the cylinder 4 is increased. When the switching valve 16 is switched so as to move forward, the air in the converter 12 is immediately communicated with the atmosphere, and the pressure of the air in the converter 12 is rapidly reduced, so that the oil pressure and the air pressure are reduced. As a result, the oil level in the converter, which was being compressed, suddenly fluctuates, causing some of the oil to flow out in the form of mist along with the air, and as a result, the oil inside the oil cylinder It had a defect that caused the amount of oil to decrease.

Particularly, when compressed air is supplied into the converter 12 and the oil in the converter 12 is introduced into the cylinder 4, and the amount of oil remaining at the bottom of the converter 12 is small, the remaining oil may be removed as described above. The oil level tends to fluctuate rapidly due to a sudden drop in air pressure, and a large amount of oil tends to flow out together with the air.

〔the purpose〕

Therefore, the present invention has been devised to eliminate such defects, and is to provide a throttle valve in the discharge section that discharges the compressed air of the converter into the atmosphere, and to gradually discharge the compressed air into the atmosphere. The throttle valve prevents the air pressure inside the converter from dropping rapidly and prevents the oil in the converter from leaking to the outside.

〔Example〕

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The details will be explained below with reference to the drawings showing an embodiment of the present invention as a drilling machine.

A main shaft cylinder 2 that rotatably supports the main shaft 1 is movably supported by a machine frame 3, and a cylinder 4 fixed to the machine frame 3 is disposed around the outer periphery of the main shaft cylinder 2. A piston 5 fixed to the outer periphery of the main shaft cylinder 2 is slidably disposed, and inside the cylinder 4, an air chamber 4A is formed above the piston 5, and an oil chamber 4B is formed below. .

The main shaft 1 has an upper end connected to a pulley 7 via a spline 6, and is rotationally driven by an electric motor 9 connected to the pulley 7 via a belt 8.

Further, a drill 1a is attached to the lower end of the main shaft 1.

Further, a switch operating cam 10 is attached to the lower end of the main shaft cylinder 2 so as to extend parallel to the main shaft cylinder 2, and a first and second micro switch L is mounted opposite to the operating cam 10.
S-1 and LS-2 are each provided in the machine frame 3 so as to be movably adjustable.

A pneumatic/hydraulic converter 12 is connected to the oil chamber 4B of the cylinder 4 via a throttle valve 11, and a check valve 13 and a first solenoid valve 14 are connected in parallel with the throttle valve 11, respectively. has been done.

The pneumatic/hydraulic converter 12 has a connection port 12B with the cylinder 4 at its lower end, and an air supply port 12 at its upper end.
A is provided, and a float 15 is floated on the internal oil level to stabilize the oil level.

The air supply port 12A of the pneumatic/hydraulic converter 12 and the air chamber 4A of the cylinder 4 are connected to the second solenoid valve 1.
6 connection ports 16a and 16b, respectively.

A compressed air supply source 17 is connected to the supply port 16c of the solenoid valve 16, a muffler 19 is connected to one discharge port 16d via a second throttle valve 18, and a silencer 19 is connected to the other discharge port 16d. A muffler 20 is connected to 16e.

The drawing shows the main shaft cylinder 2 in its original position.
In this state, the first and second Tsuremade valves 1
4.16 are not connected to each other, the air chamber 4A side of the cylinder 4 is communicated with the atmosphere, and the air supply port 12A of the pneumatic/hydraulic converter 12 is connected to the compressed air supply source 17, and the compressed air is supplied. Compressed air from the source 17 is supplied to the air supply port 12A of the pneumatic/hydraulic converter 12, the liquid level is pressed downward, and the oil on the converter 12 side is compressed toward the cylinder 4 side.

In this state, when a power switch (not shown) is turned on, the electric motor 9 is rotated, and the belt 8 is rotated.
, the main shaft 1 is rotated via the pulley 7 and the spline 6,
Drill 1a is driven to rotate.

Next, when the start switch (not shown) is pressed, the second solenoid valve 16 is energized, and the compressed air from the compressed air supply source 17 is supplied to the air chamber 4A of the cylinder 4, causing the piston 5 to move. The main shaft cylinder 2 is moved forward through the shaft.

Further, along with pressing the start switch (not shown),
The first solenoid valve 14 is also energized, and most of the oil discharged from the oil chamber 4B of the cylinder 4 as the piston 5 moves is transferred to the air pressure via the first solenoid valve 14.
is introduced into the hydraulic converter 12.

As oil is introduced into the converter 12, the oil level is moved upward, and the air in the converter 12 is transferred to the second solenoid valve 16, the second throttle valve 18, and the silencer 1.
9 to the atmosphere.

At this time, since the amount of air released from the converter is regulated by the second throttle valve 18, the air pressure in the converter 12 does not drop suddenly but is gradually lowered. Since oil is smoothly led out from the oil chamber 4B to the pneumatic/hydraulic converter 12 via the first lever valve 14, the main shaft cylinder 2 is moved forward at a rapid rate.

During the forward movement of the main shaft cylinder 2, the switch operating cam 10 engages with the micro switch LS-1, and the switch ts-1
When activated, the solenoid valve 14 is energized and the oil in the oil chamber 4B of the cylinder 4 is led out to the pneumatic/hydraulic converter 12 only through the first throttle valve 11. The main shaft cylinder 2 is fed for cutting at a speed adjusted by the first throttle valve 11.

Note that the microswitch LS-1 continues to be operated by the action of the switch actuating cam 10 even if the main shaft cylinder 2 is further moved forward.

When the main shaft cylinder 2 is fed for cutting and the switch actuating cam 10 engages with the micro switch LS-2 and the switch is actuated, the second solenoid valve 16 is energized.
The supply of compressed air to the cylinder 5 is stopped, and compressed air is supplied from the compressed air supply source 17 to the air supply port 12A of the pneumatic/hydraulic converter 12, and the oil level is pushed down by the supply, and the oil level is pushed down to the converter 12. The oil therein is led out to the oil chamber 4B of the cylinder 4 via the check valve 13, and the piston 5 is pushed upward accordingly, causing the main shaft cylinder 2 to quickly return to its original position.

The air in the air chamber 4A of the cylinder 4 is discharged into the atmosphere via the second solenoid valve 16 and the muffler 20.

The present embodiment is operated as described above, and the second throttle valve 1 is connected to the discharge port 16d of the second Tsuremade valve 16.
8 is connected, when the compressed air supplied to the air supply port 12A of the pneumatic/hydraulic converter 12 is released into the atmosphere as the second solenoid valve 16 is switched, the The discharge amount is regulated by the second throttle valve 18, and the air pressure in the converter 12 does not drop suddenly but gradually decreases. There is no possibility that the oil will leak out in the form of mist along with the air.

Further, the present invention is not limited to the above-mentioned embodiment, and may be modified as appropriate without departing from the gist of the present invention. This may be implemented in a feeding device for a table that transfers objects, and furthermore, although the second throttle valve 18 in this embodiment can change the discharge amount, it may not be possible to change the discharge amount. .

〔effect〕

As detailed above, this invention prevents oil from leaking from the pneumatic/hydraulic converter to the outside by installing a throttle valve in the circuit where the compressed air in the pneumatic/hydraulic converter is released into the atmosphere. It is possible to do so, and its practical effects are extremely large.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of a conventional drilling machine, and FIG. 2 is an explanatory diagram of an embodiment of the present invention. 1 is the main shaft, 2 is the main shaft cylinder, 4 is the cylinder, 5 is the piston,
11 is a first throttle valve, 12 is a pneumatic/hydraulic converter, 1
3 is a check valve, 14 is a first solenoid valve, 16 is a second solenoid valve, 7 is a compressed air supply source, and 18 is a second throttle valve.

Claims (1)

[Claims for Utility Model Registration] A machine tool in which a movable body 2 supporting either a processing tool 1a or a workpiece is reciprocated toward the other, the movable body 2 having a piston 5 connected to it. The forward moving side of the piston 5 is an air chamber 4A, and the backward moving chamber side of the piston 5 is an oil chamber 4B.The lower end is connected to the oil chamber 4B of the cylinder 4, and
a pneumatic/hydraulic converter 12 provided with an air supply port 12A at its upper end; and an oil cylinder connected between the converter 12 and the cylinder 4 and flowing toward the converter 12 at least when processing the processing tool 1a. a first throttle valve 11 that regulates the amount of oil discharged from No. 4 and controls the forward movement speed of the moving body 2; When oil is introduced into the converter 12 from the cylinder 4 as the piston 5 is moved forward, its own passage is opened and closed to switch the feed speed of the moving body 2. A switching valve 14, which is provided in parallel with the switching valve 14 and the first throttle valve 11, allows oil to flow from the converter 12 toward the cylinder 4, and prevents oil from flowing in the opposite direction. A check valve 13 for blocking, a connection port 16a connected to the air supply port 12A of the converter 12, a connection port 16b connected to the air chamber 4A of the cylinder 4, and a compressed air supply source 17 connected It has a supply port 16c and first and second discharge ports 16d and 16e that are open to the atmosphere, and when the movable body 2 moves forward, the supply port 16c and the connection port 16b are provided.
A state in which compressed air is supplied to the air chamber 4A of the cylinder 4 by connecting the converter 12 to the atmosphere by connecting the connection port 16a and the first discharge port 16d, and a state in which the converter 12 is communicated with the atmosphere, and a return movement of the moving body 2 At times, the supply port 16c and the connection port 16a are connected to supply compressed air into the converter 12, and the connection port 16b and the second discharge port 16e are connected to communicate the air chamber 4A of the cylinder 4 with the atmosphere. a switching valve 16 that can be switched to a different state; and a second throttle valve connected to a discharge port 16d of the switching valve 16 for regulating the amount of compressed air discharged from the converter 12 into the atmosphere from the discharge port 16d. 18. A feed control device for a machine tool comprising: