JPH039963Y2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a device for preventing chatter in a boring tool having a long quill.

<Prior Art> A boring tool used for boring processing has one end attached to a main shaft 1 and the other end rotatably supported by a supporter 2, as shown in FIG. In order to suppress the chatter of the boring tool 3, conventionally, a plurality of damper members 6 were fitted into the hollow hole 5 of the quill 4, and a gap was provided between the damper members 6 and the hollow hole 5 in the radial direction. The gap between the damper member 6 and the quill 4 provides vibration damping properties.

In the above-mentioned boring tool, when the diameter of the drilled hole in the workpiece becomes smaller, the outer diameter of the quill must be reduced, making it difficult to provide a damper member within the quill.

To counter this, a lever is provided on the bed so that it can be rotated around an axis parallel to the axis of rotation of the quill, and a weight is provided at one end of the lever to force the lever against the cylindrical outer surface of the quill using gravity to prevent vibration. A device has been devised.

<Problems to be solved by the invention> Since the above-mentioned vibration prevention device is configured to place a weight on the cylindrical outer surface of the quill after the boring tool moves forward, a cylinder device that lifts one end of the lever on the weight side is required. Is required. or,
When moving the boring tool forward, a limit switch is required to confirm that one end of the lever has been lifted. As a result, there was a problem in that the cost of the entire device increased.

<Means for Solving the Problems> The present invention has been made to solve the above-mentioned problems.A weight that contacts the cylindrical outer peripheral surface of the quill from above is provided so as to be movable in the vertical direction. An engaging member is provided that comes into contact with the weight in order to restrict the downward movement beyond a predetermined level, and at least one of the quill and the weight is formed with a tapered portion that comes into contact and lifts the weight when the boring tool moves forward.

<Operation> The boring tool is advanced in a state where the weight is in contact with the locking member and its descent is restricted. As the boring tool moves forward, the quill and the weight come into contact with each other at the tapered portion, and the weight is lifted and rests on the cylindrical outer peripheral surface of the quill.

<Example> Hereinafter, an example of the present invention will be described based on the drawings. In FIGS. 1 and 2, 10 is a spindle head installed on a bed (not shown), and this spindle head 10 is movable in the left-right direction in FIG. A main shaft 11 is rotatably supported on the main shaft head 10 so as to be rotatable around a horizontal axis, and a boring tool 12 is coaxially attached to one end of the main shaft 11. The boring tool 12 consists of a quill 13 that is long in the axial direction of the main shaft 11 and has a cylindrical cross section, and a cutting tool 14 that is attached to the quill 13 at several locations in the axial direction. A tapered portion 15 is formed at one end of the quill 13.

Further, a table 20 is installed on the bed (not shown), and a supporter 21 is installed on this table 20. The supporter 21 is equipped with a rotary tube 22 that rotates about the same axis as the main shaft 11, and by inserting one end of the quill 13 into the rotary tube 22, one end of the quill 13 is rotatably supported. It's summery. The workpiece W is on the table 20.
is placed on the workpiece W, and machined holes Wa are formed at several locations in the axial direction of the main spindle 11 in the upper part of the workpiece W.

A top plate 31 is attached to a support 30 erected on the bed, and a pair of brackets 32 are attached to the lower surface of the top plate 31 so as to project downward. A support shaft 33 is rotatably supported by these brackets 32 around an axis parallel to the axis of the boring tool 12, and the center portion 33a of this support shaft 33 is shaped like a drum so that the diameter becomes thinner toward both ends. It is formed.

A lever 34 is supported on the support shaft 33 so that it can float around an axis perpendicular to the axis of the boring tool 12. It is supported so that it can be used. A stopper 35 is attached to the lower surface of one end of the lever 34 and is attached to the cylindrical outer peripheral surface of the quill 13 near the supporter 21, and a weight 36 is attached to the upper surface of one end of the lever 34.

A locking member 40 is provided at the lower end of the pair of brackets 32.
is fixed so as to protrude toward the table 20 side, and when the lever 34 comes into contact with this locking member 40, the lowering of one end of the lever 34 on the weight 36 side is restricted. The position of the lower end of one end of the lever 34 is set so that the lower surface of the stopper 35 comes into contact with the tapered portion 15 of the quill 13.

Next, the operation will be explained based on the above-described configuration. One end of the lever 34 on the weight 36 side is lowered by its own weight, and the workpiece W is carried in from a direction perpendicular to the axis of the main spindle 11 with the lever 34 in contact with the engaging member 40. Next, the workpiece W is raised by a known lift device (not shown), and the spindle head 10 and the boring tool 12 are advanced with the cutting tool 14 facing upward. As a result, one end of the quill 13 passes through the plurality of machined holes Wa, and as shown in FIG.
comes into contact. When the boring tool 12 is further advanced, one end of the lever 34 on the weight 36 side is lifted along with the tapered portion 15, and the lever 34 is separated from the engagement member 40. The boring tool 12 is inserted into the rotary cylinder 22 of the supporter 21 while sliding on the lower surface of the stopper 35. Next, by moving the spindle head 10 forward while rotating the spindle 11, the machined hole Wa is
processing is done. At this time, quill 13 is the winning amount of 3
The boring tool 12 is rotated while sliding against the quill 13, and a downward force from the weight 36 is applied to the quill 13, thereby preventing the occurrence of chatter in the boring tool 12. The boring tool 12 will not be shaken unless a force exceeding the load of the weight 36 is applied to the quill 13. Moreover, even if a force exceeding the load of the weight 36 acts on the quill 13,
Since the load of the weight 36 acts in a direction that cancels out the repeated displacement of the quill 13, the boring tool 12
The chatter will stop immediately.

Since one end of the lever 13 is lifted by the taper portion 15 as the boring tool 12 moves forward in this manner, a cylinder device for raising and lowering one end of the lever 13 is not required.

When the machining of the machining hole Wa is completed, the rotation of the main shaft 11 is stopped at a position where the cutting tool 14 faces upward, and then the workpiece W is raised. When the spindle head 10 is moved backward in such a state, the lever 13 follows the taper portion 15.
One end of the lever 13 is lowered and the lever 13 comes into contact with the engaging member 40 . When the quill 13 is further retreated, the quill 13 is pulled out from the plurality of machined holes Wa.

In addition, as shown in FIG. 4 as another modification,
An actuating member 51 to which a weight 50 is attached is guided by a top plate 52 so as to be movable in the vertical direction, and this actuating member 5
An engaging portion 53 that contacts the top plate 52 may be formed at the upper end of the weight 1 to restrict the downward movement of the weight 50.

In addition, as another modification, the quill 13 is added to the deposit 35.
An inclined surface (tapered portion) may be formed that is inclined in the axial direction.

As another modification, the lever 34 or the stopper 35 itself may have the function of a weight without providing a separate weight 36.

As another modification, if the spindle 11 can be stopped rotating while the cutting tool 14 is oriented horizontally, and the workpiece W can be released in the direction in which the cutting tool 14 is separated from the machined hole Wa, the workpiece W can be hit in the middle of the quill 13. Gold 3
5 may be brought into contact with each other.

<Effects of the invention> As described above, the invention provides a weight that contacts the cylindrical outer surface of the quill from above and is movable in the vertical direction. Since a mating member is provided and at least one of the quill and the weight is formed with a tapered part that abuts and lifts the weight by advancing the boring tool, a cylinder device and a limit switch are not required, and the cost of the entire device can be reduced.

[Brief explanation of the drawing]

Fig. 1 is a plan view of a chatter prevention device showing an embodiment of the present invention, Fig. 2 is a sectional view taken along the line - - in Fig. 1, Fig. 3 is a diagram of the state in which the weight is lifted, and Fig. 4 is another modification. FIG. 5 is a longitudinal sectional view of a chatter prevention device, and FIG. 5 is a sectional view of a conventional chatter prevention device. 11... Main spindle, 12... Boring tool, 13
... Quill, 14 ... Bit, 15 ... Taper part, 33 ... Support shaft, 34 ... Lever, 35 ...
Money, 36, 50... Weight, 40... Engaging member, 53... Engaging portion.

Claims (1)

[Claims for Utility Model Registration] (1) A device for preventing chatter in a boring tool in which one end of a long quill is attached to the main shaft and a cutting tool is attached to the quill so that the cutting edge protrudes from the outer peripheral surface of the quill. A weight that abuts the outer peripheral surface of the cylinder from above is provided so as to be movable in the vertical direction, an engaging member that abuts the weight is provided to prevent the weight from descending beyond a predetermined level, and at least one of the quill and the weight is attached to a boring tool. A chatter prevention device for a boring tool, characterized by forming a tapered part that lifts a contact weight when moving forward. (2) The chatter prevention device for a boring tool according to claim 1, wherein the tapered portion is formed at the tip of the quill.