Wire electric discharge machining apparatus
An upper guide assembly includes an upper wire guide, an upper power feed contact, and a power feed contact movement device, and a lower guide assembly includes a lower power feed contact. The upper power feed contact and the lower power feed contact are configured to contact the wire electrode to supply power by moving in a horizontal direction from initial positions not contacting the wire electrode. The power feed contact movement device is configured to move the upper power feed contact in the horizontal direction from the initial position by a predetermined offset amount. The offset amount is set based on a machining condition including at least one of a condition of the wire electrode, a condition of a workpiece, and a surface roughness required for a cut surface of the workpiece.
1 . A wire electric discharge machining apparatus, comprising a wire electrode, an upper guide assembly, and a lower guide assembly,
wherein the upper guide assembly and the lower guide assembly are respectively provided above and below a workpiece, and the upper guide assembly comprises an upper wire guide, an upper power feed contact, and a power feed contact movement device,
the lower guide assembly comprises a lower wire guide and a lower power feed contact,
the wire electrode is guided by the upper wire guide and the lower wire guide and performs discharge machining on the workpiece,
the upper power feed contact and the lower power feed contact are configured to contact the wire electrode to supply power to the wire electrode by moving in a horizontal direction from initial positions not contacting the wire electrode,
the power feed contact movement device is configured to move the upper power feed contact in the horizontal direction from the initial position by a predetermined offset amount,
the offset amount is set based on a machining condition, and
the machining condition comprises at least one of a condition of the wire electrode, a condition of the workpiece, and a surface roughness required for a cut surface of the workpiece.
2 . The wire electric discharge machining apparatus as claimed in claim 1 , comprising:
a machining condition setting device; and an offset amount setting device,
wherein the machining condition setting device sets the machining condition,
the offset amount setting device, based on data indicating a relationship between the machining condition and the offset amount, sets the offset amount in accordance with the machining condition set by the machining condition setting device, and
the power feed contact movement device is configured to move the upper power feed contact by the offset amount set by the offset amount setting device.
3 . The wire electric discharge machining apparatus as claimed in claim 2 ,
wherein the condition of the wire electrode comprises at least one of a material and a diameter of the wire electrode.
4 . The wire electric discharge machining apparatus as claimed in claim 2 ,
wherein the condition of the workpiece comprises at least one of a material and a thickness of the workpiece.
5 . The wire electric discharge machining apparatus as claimed in claim 2 ,
wherein the offset amount is set, so that the offset amount in a case where the surface roughness is equal to or less than a predetermined threshold is smaller than the offset amount in a case where the surface roughness is greater than the threshold.
6 . The wire electric discharge machining apparatus as claimed in claim 1 ,
wherein the condition of the wire electrode comprises at least one of a material and a diameter of the wire electrode.
7 . The wire electric discharge machining apparatus as claimed in claim 6 , comprising:
wherein the condition of the wire electrode comprises the diameter of the wire electrode, and
the offset amount is set so that the offset amount in a case where the diameter is equal to or greater than a predetermined threshold is smaller than the offset amount in a case where the diameter is less than the threshold.
8 . The wire electric discharge machining apparatus as claimed in claim 7 , comprising:
wherein the offset amount in the case where the diameter is equal to or greater than the threshold is set so that the upper power feed contact contacts the wire electrode.
9 . The wire electric discharge machining apparatus as claimed in claim 7 , comprising:
wherein the offset amount in the case where the diameter is equal to or greater than the threshold is set so that the upper power feed contact does not contact the wire electrode.
10 . The wire electric discharge machining apparatus as claimed in claim 6 ,
wherein the condition of the workpiece comprises at least one of a material and a thickness of the workpiece.
11 . The wire electric discharge machining apparatus as claimed in claim 6 ,
wherein the offset amount is set, so that the offset amount in a case where the surface roughness is equal to or less than a predetermined threshold is smaller than the offset amount in a case where the surface roughness is greater than the threshold.
12 . The wire electric discharge machining apparatus as claimed in claim 1 ,
wherein the condition of the workpiece comprises at least one of a material and a thickness of the workpiece.
13 . The wire electric discharge machining apparatus as claimed in claim 1 ,
wherein the offset amount is set, so that the offset amount in a case where the surface roughness is equal to or less than a predetermined threshold is smaller than the offset amount in a case where the surface roughness is greater than the threshold.
14 . The wire electric discharge machining apparatus as claimed in claim 13 , comprising:
wherein the offset amount in the case where the surface roughness is equal to or less than the threshold is set so that the upper power feed contact contacts the wire electrode.
15 . The wire electric discharge machining apparatus as claimed in claim 13 , comprising:
wherein the offset amount in the case where the surface roughness is equal to or less than the threshold is set so that the upper power feed contact does not contact the wire electrode.