JPS6026907Y2 - Attachment mounting bolt removal detection device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for detecting removal of an attachment mounting bolt, and more particularly to a device for detecting that a mounting bolt has completely come off the ram side of a machine tool.

Conventionally, for example, when removing an attachment on a plano mill, it was possible to accidentally rotate the draw bolt in the main shaft for lifting the attachment to remove the attachment even though all of the attachment mounting bolts were not completely removed. there were.

As a result, the motor that drives the draw bolt may be overloaded, the attachment may be tilted when only some of the mounting bolts are removed, or the mounting bolt may be completely removed. If the bolt is not removed, the opening of the bolt may be damaged.

An object of the present invention is to provide an attachment mounting bolt removal detection device that detects when all of the attachment mounting bolts are completely removed from the ram of a machine tool.

This invention supplies compressed air from the compressed air supply section to each of the bolt holes of the plurality of mounting bolts that fixes the attachment to the ram of the machine tool through a throttle, and also increases the air pressure between the throttle and the mounting bolts. This objective is distantly achieved by providing a pressure switch that is activated by a change in the pressure, and using this pressure switch to detect whether or not a mounting bolt is screwed into each bolt hole.

Hereinafter, embodiments of the present invention will be described based on illustrations.

1 to 3 show an embodiment in which the attachment mounting bolt removal detection device according to the present invention is applied to a plano mill as a machine tool.

In FIG. 1, a so-called angle head type attachment 2 is fixed to a ram 1 of a plano mill with a mounting bolt 3. As shown in FIG.

The ram 1 is formed to have a square cross section (see FIG. 2), and the mounting bolts 3 are screwed into bolt holes 4 drilled at four corners of the ram 1, respectively.

Further, these bolt holes 4 are provided on the same virtual circumference centered on the main shaft 6 of the ram 1 at intervals of 90 degrees from each other.

Each of the bolt holes 4 is in communication with the lower end side of an air passage 5, and these air passages 5 are bored in the ram 1 along the longitudinal direction of the main shaft 6 of the ram 1, and are connected to the upper end side of the ram 1. are connected to the mounting bolt removal detection section 7 at the respective locations.

The main shaft 6 rotatably supported by the ram 1 is formed into a substantially circular tube shape, and a draw bolt 8 is inserted by a string into the hollow portion of the main shaft 6.

The draw bolt 8 lifts a vertical shaft 9 of the attachment 2, and a taper bush 11 is interposed between the vertical shaft 9 and the lower end of the main shaft 6 to center the main shaft 6 and the vertical shaft 9. There is.

On the other hand, a nut runner 12 is screwed onto the upper end of the draw bolt 8, and this nut runner 12 is rotatable at a predetermined height by a support member 13 that is integrated with the ram 1 or attached to the ram 1, but cannot be changed in the axial direction. The chucking motor 1
4, the vertical shaft 9 can be lifted or lowered.

The vertical shaft 9 is rotatably supported by the attachment 2, a key 16 is interposed between it and the main shaft 6, and a bevel gear 17 is fixed to the lower end side.

The bevel gear 17 meshes with a bevel gear 19 fixed to an attachment main shaft 18, and a cutter 20 is attached to the attachment main shaft 18.

Note that the reference numeral 21 in the figure is a key for positioning the ram 1 and the attachment 2.

The mounting bolt removal detection section 7 is equipped with a compressed air source 31 as a compressed air supply section, as shown in FIG. After that, it is branched into four parts and introduced into each bolt hole 4.

The compressed air after branching is communicated with the bolt hole 4 through each throttle 34, and a pressure switch 35 is provided between each throttle 34 and the bolt hole 4. It is activated when it is completely removed from the bolt hole 4 and the pressure inside the air passage 5 is reduced.

Further, all the pressure switches 35 are connected to the chucking motor 14, and the chucking motor 14 is configured not to be driven unless all the pressure switches 35 are operated.

Next, the operation of this embodiment will be explained.

The solenoid valve 33 is operated to supply compressed air at a predetermined pressure to each air flow path 5 in advance.

When attempting to remove the attachment 2 for replacement or indexing, the mounting bolt 3 must be removed first, but when the mounting bolt 3 is removed, compressed air flows out from the bolt hole 4. The pressure inside the air flow path 5 is reduced and the pressure switch 35 is activated.

At this time, each air passage 5 is provided with a throttle 34, so that when only one of the mounting bolts 3 is removed, all the compressed air flows out from the removed bolt hole 4. There is no possibility that all the air flow paths 5 will be depressurized.

All mounting bolts 3 have been removed, and each pressure switch 35 has been removed.
chucking motor 14 only when all are activated.
If any one of the mounting bolts 3 is not completely removed, the chucking motor 14 will not be driven.

When the chucking motor 14 is driven, the drive gear 15
, the draw bolt 8 is lowered via the nut runner 12, and the attachment 2 is separated from the ram 1 and lowered.

This embodiment has the following effects.

It is possible to detect whether or not each mounting bolt 3 has been removed from the ram 1, and the chucking motor 14 will not be driven unless all the mounting bolts 3 are completely removed.
The chucking motor 14 may be overloaded, the draw bolt 8 may be rotated by mistake even though some of the mounting bolts 3 have not yet been removed, causing the attachment 2 to tilt, or the mounting bolt 3 may be accidentally rotated. There is no longer any risk of damaging the bolt or the threaded part of the bolt hole 4.

Also, due to changes in air pressure in the air flow path 5, the mounting bolt 3
Since the device detects the removal status of the ) is also less difficult.

In addition, air piping is generally provided in many factories, which has the effect that the compressed air source 31 can be easily obtained.

In addition, in the above-mentioned Example, although the machine tool was explained as a plano mill, other machine tools may be sufficient.

Furthermore, the number of mounting bolts 3 is not limited to four, and may be three or less, or five or more.

Moreover, the mutual positional relationship of the bolt holes 4 corresponding to the respective mounting bolts 3 does not necessarily have to be arranged at equal intervals on the same virtual circumference.

However, if they are placed at equal intervals, attachment 2
This has the effect that it is possible to index and install the mount at any mounting angle.

Further, in the above-described embodiment, if the pressure switch 35 and the chucking motor 14 are connected and all the mounting bolts 3 are not completely removed, the chucking motor 14
Although the explanation has been made assuming that the pressure switch 35 is not driven and is in a so-called ink-locked state, the pressure switch 35 and the chucking motor 14 are not connected, and the operating state of the pressure switch 35, that is, the removal state of the mounting bolt 3, cannot be confirmed. , the operation may be performed by a working tool separately from the driving operation of the chucking motor 14.

As described above, according to the present invention, it is possible to detect that all of the attachment mounting bolts have been completely removed.

[Brief explanation of the drawing]

Fig. 1 is a partially cutaway front view showing an embodiment in which the mounting bolt removal detection device according to the present invention is applied to a plano mirror, Fig. 2 is a sectional view taken along the line ■-■ in Fig. 1, 3
The figure is a system diagram of the compressed air supply path in the mounting bolt removal detection section of the embodiment. 1... Ram of plano mill as machine tool body, 2... Attachment, 3... Mounting bolt, 4... Bolt hole, 5... ... Air flow path, 6 ... Main shaft, 7 ... Mounting bolt removal detection section, 14 ... Chucking motor,
31...Compressed air source as a compressed air supply unit,
34... Throttle, 35... Pressure switch.

Claims (1)

[Scope of utility model registration request] A plurality of mounting bolts for fixing the attachment to the ram of a machine tool, a plurality of bolt holes into which each of these mounting bolts is screwed, an air passage opened in each bolt hole and closed by the mounting bolt, Removal of an attachment mounting bolt, characterized in that the flow path is provided with a compressed air supply unit that supplies compressed air through a restriction, and a pressure switch provided between the restriction and the bolt hole. Detection device.