JPH0440142B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for checking the diameter of a material in an automatic bar processing device, and in particular, the material is checked when replacing a bar in an automatic lathe for processing bars, and bars with small diameters are mixed in. This article relates to a method to prevent this from happening.

It is well known that automatic bar processing equipment, especially NC automatic lathes, grips and rotates a bar on the main shaft with a collection chuck, and processes this using a tool such as a cutting tool.

In this case, the collect chuck can handle variations in the diameter of the material and can grip it, but it cannot handle bars with mixed material diameters, and the chuck can grip and rotate the bars. That becomes impossible.

When a bar with a large diameter material is mixed in, the bar is stopped at the rear end of the chuck and does not protrude into the machining area, and accidents to the processing equipment are unlikely to occur. If this is the case, the tip of the bar will pass through the collect chuck and protrude into the processing area.

At this time, since the bar is being fed by the feed bar of the automatic bar feeding device, the tip of the bar comes into contact with a part of the processing device and stops.

When a machining cycle is started in this state, even though the spindle chuck is closed and rotating, the bar is not gripped and therefore does not rotate, and even when a tool, etc. approaches, it is not processed, and the bar and tool etc. may interfere with each other, causing accidents such as breakage of the cutting tool or damage to the turret or spindle.

This has been widely known for a long time, but when manually replenishing the material shelf of an automatic bar feeder with bars as in the past, it is easy to notice the difference in material diameter, and the operator is also Because we are careful to check the materials, accidents like this rarely occur.

However, in recent years, automation of bar processing has progressed, and processing systems aiming for completely unmanned operation have been launched.
The replenishment of bars to the automatic bar feeder will also be affected by the automatic replenishment of bars stored in the bar stockyard by automatic guided vehicles. There has been a risk that the raw material diameter bar is supplied to the processing equipment as is without being checked.

Of course, the problem would be solved if there was a system that measures and checks the material diameter before feeding the bar, but
Since the probability of these accidents occurring is very low (probably close to zero), it is therefore not efficient to measure the diameter of all materials.

The present invention has been made in view of the above points, and after replacing the bar with a new one and closing the spindle chuck, the bar is pressed with a predetermined biasing force in the feeding direction by an automatic bar feeder. By determining that the material diameter is small (the bar is not checked) when the bar moves relative to the spindle, it is possible to easily check for a small material diameter with the addition of a small mechanism. This is what we are trying to do.

An example in which the present invention is applied to an NC automatic lathe with an automatic bar feeder will be described below.

FIG. 1 is a front view of an NC automatic lathe with an automatic bar feeder to which the present invention is applied. In the figure,
The NC automatic lathe 1 has a headstock 2 that slides in the axial direction, and a collection chuck provided on the headstock 2 grips and rotates a bar that is fed through a through hole in the main spindle.

A guide bush 3 is provided in front of the headstock (on the right side in the figure), and the bar material inserted through the main spindle 2 and fed is supported by the guide bush 3 and protrudes forward. Processed by processing means.

An automatic bar feeder 5 is provided at the rear of the NC automatic lathe 1 (to the left in the figure). In the automatic bar feeding device 5, long bars are stored and supported in a guide pipe 9 provided on a frame 8 fixed on two stands 6 and 7, and are fed to a feeding bar (details will be described later). Therefore, it is pressed in the forward direction (rightward), and as the bar is processed, it is sent out sequentially and fed into the main shaft.

As the processing of this bar progresses and the bar reaches a predetermined length, the feed bar moves back inside the guide pipe 9 while holding the bar, discards this bar (building material), and creates a new long length. automatically feeds the bar into the spindle.

The configurations of the NC automatic lathe 1 and automatic bar feeder 5 and their respective structures are already known, so they will not be described in detail here.

FIG. 2 shows an embodiment of the material diameter checking device of the present invention, which is installed at the rear end of the automatic bar feeder 5. As shown in FIG. The figure is a partially cross-sectional perspective view of the automatic bar feeder 5 seen from the back side.
A guide pipe 9 is arranged above. The guide pipe 9 has a hollow tubular shape and is provided with a notch groove 9a in the upper part.

A feed bar 10 is fitted into the guide pipe 9, and a finger chuck 13 at the tip of the feed bar 10 grips a bar w, and a chain connected to a blade 14 provided at the center 15 in the direction in which the bar material is supplied (to the left in the figure). The chain 15 is biased in the direction of the arrow with a predetermined tension by a motor and a torque clutch (not shown), and is wound between a pulley 16 and a pulley (not shown) provided at the front end of the bar supply device 5. It's being passed around.

At the rear end of the frame 8, there is a backward end detection mechanism 17 that detects when the feed bar 10 has returned to the rearmost position, and a rearward end detection mechanism 17 that detects when the feed bar 10 has returned to the rearmost position, and which removes the remaining material from the finger chuck 13 when the feed bar 10 has returned to the rearmost position. A stopper 18 for pushing out is provided. There are two limit switches 19 and 20 in front of the backward end detection mechanism 17 (on the left side in the figure), and the material diameter is checked by these limit switches. 2
Each of the limit switches 19, 20 is movable along the frame 8 and fixed at an appropriate position depending on the length of the bar.

As the bar material being processed progresses and becomes shorter, the feed bar 10 is moved back and the bar material is replaced with a new long bar material. The method and device for discharging the short bar, supplying a new long bar, and gripping the bar at this time are already known and will not be described in detail here.

After a new long bar is fed into the guide pipe, a motor (not shown) rotates, the pulley 16 rotates in the direction of the arrow, and the feed bar 10 moves the bar w into the main shaft of the NC automatic lathe 1. The tip of the bar w protrudes into the processing area and comes into contact with a part of the processing device, such as a cutting tool, a stopper, etc., and the bar's forward movement is stopped. At this time, the first limit switch 19 is fixed at a position where it is pressed and activated by the blade 14 of the feed bar 10, and the second limit switch 20 is fixed slightly forward of it.

If the diameter of the bar material fed into the guide pipe is too large, the tip of the bar material W will be stuck to the rear end of the chuck of the main shaft and will not protrude into the machining area. 14 does not advance to the normal position and does not press the first limit switch 19, so if the first limit switch 19 does not operate within a predetermined time after the feed bar 10 starts moving forward, the material diameter of the bar material is increased. It determines this and issues a signal.

When the tip of the bar w protrudes into the machining area and comes into contact with a parting tool, a stopper, etc. and stops, the first limit switch 19 is pressed and activated. The operation of this first limit switch serves as a confirmation signal, and the NC automatic lathe 1 begins to operate. The chuck of the main shaft of the NC automatic lathe 1 closes and grips the bar, and as the main shaft rotates, supporting members such as the parting tool and stopper that were in contact with the tip of the bar move back. At this time, if the diameter of the bar material is the specified size,
Since the bar is gripped strongly enough by the spindle chuck, the bar will not move in the axial direction due to the pressing force of the feed bar 10. However, if the diameter of the material is small, the feed bar will not be gripped by the spindle chuck. 10
The blade 14 presses and operates the second limit switch 20, which determines that the diameter of the material is small and issues a signal.

When these signals indicating that the material diameter is large or material diameter is small are received, the NC lathe immediately stops, lights up a signal light or other means to indicate that there is an abnormality, calls for a worker, and removes the bar material. Take necessary measures such as replacement.
Even if a predetermined period of time has elapsed since the NC automatic lathe 1 started operating, if there is no signal for large material diameter or small material diameter, it is assumed that a bar of the predetermined material diameter has been fed and has been chucked normally. Judgment, NC automatic lathe 1
Processing is started at , and the detection means for checking the material diameter is cut off.

Since the present invention is configured as described above, it is possible to check the material diameter by adding a small amount of equipment to the conventionally used automatic bar feeder, and it is possible to check the diameter of the material by adding a small amount of equipment to the conventionally used automatic bar feeder. This has many benefits, such as enabling automatic operation of the rods and preventing accidents caused by the mixing of rods with different diameters.

[Brief explanation of drawings]

FIG. 1 is a front view showing an example of an automatic bar processing device, and FIG. 2 is a partially cutaway perspective view of the left end of the automatic bar feeding device shown in FIG. 1, viewed from the rear. 1...NC automatic lathe, 2...headstock, 5...bar automatic feeder, 8...frame, 9...guide pipe,
10...Feeding bar, 14...Blade, 19,20...
Limit switch.

Claims (1)

[Scope of Claims] 1. A main shaft that inserts and grips and rotates a bar; a processing means disposed in front of the main shaft that processes the bar that is gripped and rotated by the main shaft; In an automatic bar processing device having an automatic bar feeding device that sequentially feeds the bar into the spindle from the rear as the bar is being processed, and automatically replaces the bar with a new long bar when the processing of the bar is completed. In this method of checking the material diameter, after replacing the bar with a new long bar using an automatic bar feeder, the main shaft grips the bar, and then the automatic bar feeder moves the bar in the feeding direction. Pressure is applied, the presence or absence of relative movement between the spindle and the bar material is detected, and if relative movement between the spindle and the bar material is detected within a predetermined time, it is determined that the material diameter is not the predetermined diameter. A method for checking the material diameter in automatic bar processing equipment.