JPH03281112A - Boring device - Google Patents

Abstract

PURPOSE:To improve the roundness accuracy of a bore hole, by providing a work clamp device, boring tool, work head, moving member and bore inside pressing member on the working device of the bore hole of an engine block. CONSTITUTION:A work 10 having a bore hole 10 spreads the bore holes 10b, 10d, 10f excepting a work object to the outside in the diameter direction at their bores by a bore inside pressing member after being clamped, deforming the bore holes 10b, 10d, 10f and also deforming the bore holes 10a, 10c, 10e as well with their deflection. The boring of the bore holes 10a, 10c, 10e is performed in this state. When a tool is separated from the bore holes 10a, 10c, 10e, the bore inside pressing member is also separated. At this time, the bore holes 10a, 10c, 10e become a nonroundness shape like a dotted line A. The processing of unworked bore holes 10b, 10d, 10f is then performed, but a residual distortion B is caused on the worked bore holes 10a, 10c, 10e by the cutting force in the working time thereof. It becomes in a roundness shape with this distortion B and nonroundness shape A being set off.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a hole machining device for machining a plurality of bore holes.

<Prior Art> Conventionally, when machining a plurality of bore holes arranged in a workpiece of an automobile engine block, for example, as shown in FIG. 7 and FIG. A plurality of spaced bore holes 1, 3.5 are machined into perfect circular shapes, and then the workpiece is transferred to the adjacent processing station and the boring tool M4. The remaining bore holes 2, 4.6 are machined into a perfect circular shape using M5 and M6, and one workpiece is machined. The reason for dividing the bore hole machining process as described above is that it is extremely difficult to arrange a boring tool in accordance with the arrangement of the bore holes because the distance between adjacent bores is short.

<Problems to be Solved by the Invention> However, due to the cutting force during machining of the bore holes 2, 4.6, residual strain is generated in the bore holes 1, 35, which have been machined first, resulting in the distortion shown by the two-dot chain line in Fig. 9. Since the hole is deformed into an elliptical shape, there is a risk that the accuracy of the roundness of the bore hole may deteriorate.

<Means for Solving the Problems> The present invention has been made to solve the above-mentioned problems. a boring tool; a machining head to which the boring tool is mounted and movable in a direction parallel to the axis of the bore hole; and inserting the boring tool into an unmachined bore other than the bore to be machined into which the boring tool is inserted; A moving member that is detached, and a bore inner pressing member that is provided on the moving member so as to be expandable and contractible in the radial direction of the unprocessed bore, and that expands and distorts and deforms the unprocessed bore, thereby simultaneously deforming the bore to be processed. It is something that

<Operation> With the above-described configuration, after a workpiece having a bore hole is clamped by the clamp device, the moving member is inserted into the bore hole other than the one to be machined, and the bore inner pressing member provided on the moving member presses the bore. It expands outward in the radial direction, distorting and deforming the bore hole other than the one to be machined, and also distorting and deforming the bore hole to be machined. Under the above conditions, the bore hole to be machined is bored. When the machining head rises and the boring tool leaves the bore hole, the moving member also causes the bore inner pressing member to separate from the unmachined bore hole. At this time,
The unprocessed bore hole returns to its original shape, and the processed bore hole is processed into a perfect circular shape, but when the expansion of the bore inner pressing member is released, it becomes a non-circular shape as shown by the two-dot chain line A in Fig. 5a. It becomes circular. Next, two tools are inserted into the unmachined bore hole using the machining head, and the unmachined bore hole is machined. Residual strain occurs in the bore hole. This distortion and the above-mentioned non-round shape when the bore inner pressing member is expanded cancel each other out, and the machined bore becomes a perfect circle shape, and the roundness accuracy of the bore after processing is improved. > Examples of the present invention will be described below based on the drawings.

In FIGS. 1 and 2, a work W such as an engine cylinder block has a plurality (six) of bores 10 arranged in an array, and one end surface perpendicular to the axis of the bore hole 10 is used as a reference surface 11. It is fixed to the jig main body 12.

The jig main body 12 includes a reference block 13 against which the reference surface 11 of the workpiece W comes into contact, and clampers 14 and 15 that press the reference surface 11 against the reference bronck 13. An end 14a of the clamper 14 is connected to a cylinder 17a, and is provided on the jig main body 12 with the support shaft 16 as the center of swing.An end 15a of the clamp bar 15 is connected to a cylinder 17b, and is provided on the jig body 12 with the support shaft 16 as the center of swing. as the center of oscillation,
It is provided in the jig main body 12. These clampers 14
．． 15 are arranged at the four corners of the workpiece W, for example.

A positioning dowel pin 20 is provided at the bottom of the jig main body 12 and is movable up and down by a circuit cylinder, and a dowel hole 21 corresponding to this positioning dowel pin 20 is formed in the reference surface 11 of the work W. There is. The work W is positioned by fitting the knock pin 20 into the knock hole 21.

An auxiliary clamper 24 and a natural clamper 25 are erected on support stands 22 and 23 on the jig main body 12 so as to sandwich the workpiece W along the conveyance direction of the workpiece W. An auxiliary clamper 24 is attached to the upper part 22a of the support stand 22, which comes into contact with the left side outline of the work W in FIG. is attached.

Note that the auxiliary clamper 24 uses a cylinder 26 to hold the workpiece W.
The clamper 25 can be moved forward and backward relative to the workpiece W by means of the cylinder 27.

A connecting plate 40 is provided behind the natural clamper 25 of the support base 23. A cylinder 42 that is movable downward is connected to one end 41 of the connecting plate 40. A support plate 44 substantially parallel to the north surface of the workpiece W is connected to the other end 43 of the connection plate 40. A moving member 45 inserted into the bore 10 is provided on the support plate 44 . This moving member 45 includes a pair of bore inner pressing members 46, 4.
7 is slidably inserted in the radial direction. The diametrically outer sides of these bore inner pressing members 46, 47 are formed in a semicircular arc shape so that they can be easily inserted into the bore 10. Further, the axially opposing surfaces of the bore inner pressing members 46 and 47 are concave. Bottom portions 46a and 47b are formed.

Between these bottom parts 46a and 47a is a spring 4B that urges the bore inner pressing members 46 and 47 to the bore diameter outer side.
is interposed therein, and the urging force of this spring 48 causes the bore inner pressing members 46, 47 to press against the flange 46a.

The work W
As shown in FIG. 2, since a space S is formed that extends in the vertical direction, the bore 10 is distorted and deformed radially outward by the expansion of the bore inner pressing pins 46,47. Note that the moving members 45 are arranged at every other bore 10 arranged in plurality.

Reference numeral 50 denotes a transfer machine which is movable in the transport direction for transporting the workpiece W to the next process, as shown in FIG. 3, and is rotatable about the axis.

The transfer bar 50 crosses the conveyance direction at a position in front of the support stand 23, and the transfer bar 50 is provided with transfer arms 51 located at the front and rear of the workpiece W.

In the direction of conveyance of the work W by the transfer par 50,
A processing device 32 and a processing device 33 are installed apart from each other, and each processing device 32.33 has a processing head 32a, 33 that is moved up and down via a ball screw of a circuit by a motor 34.35.
a, and boring tools 30a and 30b that are rotatably provided around a vertical axis on each of the processing heads 32a and 33a and are rotationally driven by motors 32b and 33b.

These boring tools 30a make the bore holes 10a, 1
0c and 10e are machined, and bore holes 10b, 10d, and 10f are machined using a boring tool 30b.

Next, the operation of the present invention will be explained based on the above-described configuration.

First, the work W is sandwiched between the transfer arms 51 and transported to the processing device 32 by the transfer par 50. The clamper 14 is moved to the support shaft 16 by the cylinder 17a.
The cylinder 17b causes the clamper 15 to swing counterclockwise about the support shaft 18, so that the reference surface 11 of the work W is aligned with the reference block 13.
The workpiece is fixed by contacting the dowel pin 2.
0 fits into the dowel hole 21 formed in the work W by the cylinder of the circuit, and the work W is positioned.

When the workpiece W is positioned and fixed as described above, the fourth
As shown in Figures 5a, 5b and 6, the cylinder 4
2, the moving member 45 positioned above the bore holes 10b, 10d, and 10f is inserted into each bore hole 10 via the connecting plate 40. Bore inner pressing member 46.47 of each moving member 45
The inner peripheries of the bores tob, 10d, and LOf are pressed and distorted radially outward by the biasing force of the spring 48 housed therein, thereby deforming them into an elliptical shape as shown by the two-dot chain line in FIG. As the bore holes 10b, 10d, and 10f are deformed, the bore holes 10a, 10c, and 10e are also deformed. In the above state, the hollowing tools 30a, 30a, 30a are lowered by the motor 34 via the ball screw of the circuit and inserted into the bore holes 10a, 10c, 10e.
Perform processing of 0c and 10e. Bore holes 10a, 10c, 1
0e is processed into a perfect circle.

When the bore holes 10a, 10c, 10e are finished, the boring tools 30a, 30a, 30a are raised to the initial position by the motor 34, and then the cylinder 42
The bore holes 10b and 10d.

The moving member 45, 45, 45 inserted in 10f is the connecting plate 4
Rising through 0. At this time, the bore holes 10a, 10c, and 10d, which are machined into perfect circular shapes, are connected to the bore inner pressing portions 46, 4.
By releasing the expansion in step 7, it elastically returns to the elliptical shape shown by the two-dot chain line A in FIG. 5a.

Next, in order to process the bore holes 10b, 10d, and 10f, the workpiece W is held between the transfer arms 51 and conveyed to the processing device 33 by the transfer par 50. The positioning and fixing of the workpiece W in the processing device 33 is the same as the operation when processing the bore holes 10a, 10c, and 10e described above, so a description thereof will be omitted here.

0 Next, the three hollowing tools 31a, 31a, 31a drill into the bores 10b, 10d,
1. It is inserted into the bore holes 10b, 10d, 10f by the motor 35 via the pole screw of the circuit, and the bore holes 10b, 10d, IOf are processed. Here, the moving member 4 processed into a perfect circular shape in the previous process
5 are bore holes 10b, 10c1. ．． The bore holes 10a, 10c, and 10e, which are deformed into elliptical shapes as shown by the two-dot chain line A in FIG. 5a by separating from the bore hole f, are separated from the bore hole f.
Due to the influence of cutting force when machining ob, 10d, and 10f,
Since it is distorted into an elliptical shape as shown by the two-dot chain line B in FIG. 5b, the distortion of this line B and the elliptical shape of the line A in FIG. , the roundness accuracy of the bore hole improves.

As described above, the present invention is advantageous when machining a plurality of arranged every other bore holes 10, 10b, 10d, 1 . Of
1. In the previous step, bore holes 10a, 10c, 10e were formed.
The bore holes 10b, 10d,
When machining 10f, the residual stress is removed and the distortion of the bore holes 10a, 10c, 10e is eliminated by elastic force, and the circular accuracy of the bore hole 10 is improved.

<Effects of the Invention> As described above, the present invention is advantageous in that when applying pressure to every other bore hole in a plurality of arrays in the pre-process and post-process, it is possible to By inserting a bore inner pressing member into the processed bore hole and distorting and deforming the unprocessed bore hole outward, the bore hole to be processed can also be deformed,
In this state, it is processed into a perfect circle, and by releasing the deformation by the bore inner pressing member, it is deformed into a non-perfect circular shape. Due to the cutting force when machining the unmachined bore hole in a subsequent process, residual distortion occurs in the machined bore hole. This residual strain and the non-perfect circular shape indicated by -F when the bore inner pressing member is expanded are offset, and the machined bore hole returns to a perfect circular shape. Therefore, the roundness accuracy of the bore hole is improved.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the workpiece distortion processing device of the present invention, and FIG.
The figure is a diagram to explain the bore pusher No. 1 part, Figure 3 is a diagram showing the processing equipment arranged on the processing line, Figure 4,
5a, 5b, and 6 are leap diagrams showing the order of machining the bore in the present invention, and FIGS. 7 to 9 are diagrams showing the order of machining the conventional bore. 10... Bore hole, 11... Reference surface, 12... Jig body, 13... Reference block, 1415... Clamp device, 20... Dowel pin for positioning, 23... Support stand, 24... Auxiliary clamper, 25... Natural clamper, 30a 30b... Boring tool, 3
2.33...Processing equipment, 40...Vertical movement bar, 45
...Moving member, 46.47...Bore inner pressing member,
50...Transfer bar, 5I...Transfer arm.

Claims (1)

[Claims] (1) A clamp device that clamps a workpiece that has a plurality of arranged bore holes, a boring tool that processes the bore holes, and the boring tool that is mounted and moved in a direction parallel to the axis of the bore holes. a movable member that is inserted into and removed from a raw bore other than the bore to be machined into which the boring tool is inserted; and a movable member that is provided so as to be expandable and contractable in the radial direction of the raw bore. and a bore inner pressing member that simultaneously deforms the bore to be machined by distorting and deforming the unmachined bore.