SU486887A1 - Device for EDM flashing curvilinear holes - Google Patents

Description

one

This invention relates to the EDM technology. With the help of EDM firmware, curvilinear holes, such as lubrication, and gas exhaust ducts, can be obtained in hard-to-reach places of machines and devices.

Devices for electroerosive flashing of curvilinear holes of constant curvature by a radially curved electrode-tool fixed in an electrode holder mounted rotatably around an axis coinciding with the center of curvature of the electrode-tool are known. In this case, the electrode holder is rotated due to the direct action of the spindle of the machine on any part of the shoulder of the electrode holder.

When machining holes h: a large radius of curvature, such devices have very large dimensions, while the machining accuracy is reduced due to the long arm length of the electrode holder.

In order to increase the machining accuracy and reduce the size of the device, when flashing holes of a large radius of curvature, a removable insert with copy grooves is inserted into the proposed device, along which guide fingers attached to the electrode holder are mixed under the influence of the machine spindle. These grooves are made concentric to the electrode-tool, bent along the radius corresponding to the curvature of the machined hole.

FIG. 1 shows the proposed device; in fig. 2 shows a section along A-A in FIG. one.

The device includes a frame 1 installed on the table of the electroerosive machine,

in which are placed the pushers 2, resting on the springs 3. In the vertical groove of the frame fixed by pins 4 a removable insert 5 with two curvilinear copied grooves. The electrode holder 6 is made

in the form of a bar and held in the upper position by the pushers 2. The radially curved electrode-tool 7, whose cross section corresponds to the contour of the hole being pierced, is fixed on the bar 8,

installed in the electrode holder, with a screw 9. The fingers 10 are secured to the electrode holder and inserted into the slots of the interchangeable insert. There are collars on the fingers that prevent lateral displacement of the electrode holder. Item 11 is mounted on a stand 12 mounted on the table 13 of the machine. The roller 14, mounted on the shpinindle 15 of the machine, acts on the electrode holder. Copy grooves in a replaceable insert are made concentric with respect to the center of curvature of the electrode-tool. In this case, the values of the radii RI and Rz of the copier grooves are determined depending on the radius of the curvature of the electrode tool, the distance I1 between its axis and the axis of the copier groove nearest to it, and the distance I2 between the grooves.

Processing using the device is carried out as follows.

The roller 14 acts on the electrode holder, as a result of which the latter rotates around the center Oi, which is the center of curvature of the tool electrode. At the end of the patch, the spindle moves up and under the action of springs 3 and pushers 2, the electrode holder moves to its original position.

The dimensions of the fixture do not depend on the radius of the hole being forgiven. The transition from one radius to another is accomplished by changing the electrode tool and the interchangeable insert.

Due to the rigid direction of the fingers, an accurate movement of the electrode tool along the desired arc is ensured.

Subject invention

A device for electroerosive forgiveness of curvilinear holes of constant curvature by an arcuate electro-tool fixed in an electrode holder that can be rotated around an axis that coincides with the center of curvature of the tool electrode, in order to increase machining accuracy and reduce dimensions

when flashing holes of a large radius of curvature, it has a removable insert embedded with at least two coping grooves concentric to the tool electrode, which include

guide pins attached to the electrode holder.

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