JPS5981022A - Wire cut taper machining method - Google Patents

Abstract

PURPOSE:To enable a work to be machined in an optional tapered shape, by extending a straight line, which connects corresponding points on upper and bottom sufaces of the work machined in the tapered shape, and obtaining crossing points between the extended straight line and control surfaces so as to control the route of an electrode, in the case of the work provided with a space between the upper and the bottom surfaces of the work and the control surfaces of the wire electrode. CONSTITUTION:A work is machined by wire cut electric discharge machining in a tapered shape having different shapes between upper and bottom surfaces of the work. A wire electrode WR is controlled in the direction of two axes (XY axes) on control surfaces FCS, SCS of a guide and moved by control in the direction of four axes in total. Coordinates of points Qi, Ri, in which a straight line, connecting two points P1, P2 and extended, crosses the control surfaces FCS, SCS, are obtained from the coordinates of the machining points P1, P2 on the upper and the bottom surfaces US and DS of the work WK machined in said shape. The guide of the wire electrode is moved on a route connecting these crossing points, thus enabling the work to be machined in an optional tapered shape.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a wire cut taper machining method, and in particular, the relative movement between the shear wire and the workpiece is achieved by simultaneously controlling two axes on two control planes and simultaneously controlling four axes as a whole. The present invention relates to a wire cut taper processing method in which a predetermined taper processing is performed on a workpiece by controlling

As is well known, a wire cut free-flow milling machine (t) is one in which a wire is stretched between an upper guide and a lower guide, and an electrical discharge is generated between the wire and the workpiece to process the workpiece. The workpiece is fixed on the table and moved in the X and Y directions according to the instructions from the numerical control device along the machining shape.
Let's do it. In this case, if the wire is stretched perpendicularly to the table (workpiece), the machining shape on the top surface of the workpiece and the first surface will be the same, and the upper guide or lower guide will be moved in the X, Y direction (() axis, (1) The upper kite or the lower guide is deviated in a direction perpendicular to the one direction in which the workpiece is moved, and the wire is tilted relative to the workpiece. The machining shape is the same as that of the wire, and so-called taper machining is performed in which the loe surface is inclined.

Figure 1 is a clear diagram of the oil for taper machining, where the wire WR is placed between the upper guide UG and the lower guide DG.
It is stretched at a predetermined angle with respect to K. Now, set the lower surface PL of the work WK to the program shape (the upper surface Q of the work WK
, U may be a program shape) and 17, and the taper angle α and the distance 1tl between the upper guide UG and the lower guide DG.
11. The distance from the lower guide DG to the lower surface dimension of the workpiece WK, the offset i d+ of the lower kite DG with respect to the lower surface PLK of the workpiece, and the offset amount d of the upper guide LJG,
are respectively (11=h*tinα−d,=n*tgna−h°tan(1−;”He1nn
α-d.

It can be expressed as The machining width is d8i.

Therefore, depending on the four movements of the workpiece, the offset amount d,,d,
Upper guide U to which wire WR is stretched so that
By controlling the movement of (), taper processing with a taper angle α can be performed as shown in FIG.

In the figure, the dotted line and the one-point ψt1 line are the passages of the upper guide UG and lower guide DG. As mentioned above, wire cut electric discharge machining commands include a program path on the bottom or top surface of the workpiece, and a feed point on the program path.
velocity, Taber angle α, said distance) 1. If a command such as h is given, processing will be carried out according to the command.

By the way, recently, the top surface shape and bottom surface shape are completely different from each other.
For example, there is a demand for parts whose top surface is a straight line and whose bottom surface is an arc.

However, conventional taper processing methods have not been able to process parts with very large shapes.

In light of the above, it is an object of the present invention to provide a novel taper machining method that can process a component having a given upper and lower surface shape.

Hereinafter, the present invention will be explained in detail with reference to the drawings.

In the following explanation, the program plane will be referred to as the first control plane (X
The surface to which the lower guide is moved will be described as the second control surface (UV lower guide movement surface), but the present invention is not limited to stiffness as a method of selecting the control surface.

FIG. 3 is an explanatory diagram of the relationship between the control surface and the component surface, WK
i, j components, [J S is the top surface of the component, L) 8 iJ component bottom surface, Wllll wire, FO8r, t program surface 1st control L11tfri (X Y program surface)
, SO8 is the second control surface (UV lower guide movement surface) which is the movement surface of the lower guide, and 1 part WK is the upper surface U of the part.
S parallel parts] -hl) 8 is t+, -LjlXYbuc
The +f ram 1iiFO8, the UV guide moving surface SO8, and the VC are arranged so as to be parallel to each other.

In Figures 4 and 5, the top surface of the part is circular, and the part 1
When the il shape is a square, it is an explanatory diagram illustrating the wire passage in the XY zigzag plane and the v1 guide movement.
)) The figure shows the projection of the LXY program onto the JV lower guide ladder plane. In Fig. 4, the tiX Y program plane F08 and the part top 1lliIUS are Pj,
-F guide moving surface SO8 and the bottom surface of the component])S?
5+ feet apart. As a result, the wire path PILI) on the XY program plane FO8 is circular, but
V lower guide 44 'dHJj plane SO8 wire passage DG
P has a flat shape with a distorted square. on the other hand,
In Figure 5, the XY program plane FO8 and the top surface U of the component are shown.
The lower guide moving surface SO8 and the lower surface of the component are also separated from each other. As a result, the XY program plane F (3
The wire path PRP of 8 is no longer circular but has a distorted shape, and the wire path D of the UV lower guide #trend SO8
GI) is also not square but has a distorted shape.

Now, the present invention I/(Now, H
When there is a gap between the two surfaces, find the position of the point (projection point) where a straight line connecting corresponding points on the top surface of the component and the bottom surface of the component intersects the control surface of the set with the gap,
After that, the wires are set so that they simultaneously trace corresponding points on the XY program plane, UV lower guide, and V moving plane.
Using the position data of these corresponding points, four-axis control is performed to perform four machining operations with different shapes on the top and bottom surfaces of the parts.

FIG. 6 is an explanatory diagram illustrating the taper processing method of the present invention. In the figure, v3 is the distance from the top surface US of the component to the bottom surface J) S, V4 is the distance from the top surface US of the component to the XY block plane F (j S, and ■ is the distance from the top surface of the component Uv lower kite movement surface S (i is the distance to 8.

In addition, Pl is a point on the wire path at the top surface U''S of the component, and a point on the wire path at the bottom surface U''S of the component, and the points P, , P, are known and the first
It is assumed that they correspond to each other. Furthermore, Qi and Ri are the direct expansion P connecting the corresponding points b and h on the top and bottom surfaces of the component.
, the points (projection points) where the plane intersects the XY program plane 1i' OS and the %UV lower guide movement plane SO8, respectively.
It is. Also, the origin of the machine coordinate system is 0, and the coordinate axes Xm,
Ym and Zm shall be taken as shown in the figure (however, Y
axis perpendicular to the paper).

Now, V,, V,, V, and points J',, P
, is known as described below. Therefore, from these 11 values, the XY program surface O8 and UV] guide movement surface 8
Coordinates of projection points Qi and Ri at 08 (XMt, Y
M>.

ZMt ), (XM, , YM, , ZM, )
h, these corresponding projection points Qi, Ri
(i = 1.2...) is controlled simultaneously on the X and Y program planes, and U and V are simultaneously controlled on the UVT-guide movement plane, resulting in a total of 4 simultaneous axes as a whole.
By controlling the axis, desired parts can be obtained.

Now, if the coordinates of point P are (xx, yx, o) and the coordinates of point h are (x2.Yt, -V,), then the unit vector of vector B (=RQi) in the same direction as wire W Each axis component "t J+ k is i = (xt - xt)/shi4-'xl - xt
') wa ('It -Vt-)'-+Vs' (1
) J = CYl-'It)/%/(X animals-xt,
l"-+ 0'*-return'-+-v,' (21k =
Vs / v" (Xt - Xt 7+ ('It -
Yt) + VB" (31. Therefore, the Z-axis coordinate ZM of point Qi is ZM, = November・k ==lDI"Vs/'v'(xt Xt) +CYt
3't)"+VT(41) By the way, ZM is equal to the distance from 1fii U S to the XY program plane on the part, so V4 = IB! ・vl/
V/(XI%)”+-(Yr-:Yt)”+Vs”
− becomes. Therefore, the magnitude of vector B is .

”: From, the X-axis and Y-axis external coordinate values of the projection point qH XM1゜T
hl, Namazoilzo1] To X11 = XI + November ・1Thf,
= V, + IHI −j, and the projection point Qid)
A sign is sought. Similarly, each axis coordinate value XM of the shadow point Ri of the UV-tokaido displacement ji#.

zM, =-V6O13 becomes.

Next, from equations (6) to (9), we can calculate the projection point coordinates Xi, 'Yi on the XY program plane, and the projection point from the projection point Qi on the XY program plane to the projection JR・i on the UV lower guide axis dynamic plane) Find the axis components Ui and Vi of /I/, Xi, Y
i, Ui, Vi fN (3 data in the memory as ii: (, fi. output, Xi.

Yi, Di, Vi are the axial components of the lower guide movement vector, and Xi, Yi are the axial components of the workpiece movement vector when the top surface of the part and the XY program plane are aligned. Become.

Then, from now on, for all corresponding points on the second side and the bottom side of the part,
51, (6) to (9), 11111 for ft11 type t
Next Xi, Yi, Ui.

Find Vi (i = 1.2.3...), and in memory, i
If Ui and Vi are determined, the stiffness will be set as No data and 1-
A No. tape is created using the No. tape (tape operation), or a wire cut electrical discharge machine is controlled by the same 4-axis control using the No. tape (tape operation) or reading out one block at a time from the memory (memory operation).

Next, inputting the shape of the top and bottom surfaces of the component will be explained in detail. FIG. 7 is a partial plan view of the parts. Now, let's look at the line elements in the top surface shape of the component PUP and the bottom surface shape of the component PDP (
17,0,,G,,G,;G,,G4. G6
．． G, and line element ()1 to, G, and G, ,G, and 06. G7 and 080. Assuming that . . . corresponds to each other, the part shape definition program will be as follows. However, point S, ~”Ion arc Cl + Ot
+ (Jl is the already defined tear+l) 0'>.

(Jl:81.82.1 (to:S@, 87.1 o,':c,,c嶌S,,S,,4゜G4:
Gf v GWS? l S@+40Gs:
8. , 8. , iG, : 8. , 8. , IGi: 0. , OW, S,, S,, 50
G8: 8. , S,,, s.

Oka, in the above program, CW indicates a clockwise circular arc, and the numbers 1, 40, and 50 at the end are the number of divisions of each line element Gi. When the number of divisions is 2 or more, each division point is obtained during the No data creation process, and the VC is calculated for each corresponding division point.
(61~(91, (Xi according to formula 10.

Yi, Ui, and Vi are calculated and output as No data.

FIG. 8 is a block diagram of the present invention, and FIG. 9 is a process flow diagram.

A No. data creation program is stored in ROM No. 1 in advance. In addition, the shape data of the upper and lower surfaces of the parts X, ~V62 (the above-mentioned part shape description) is read from the tape 102 by the data reader 03 and stored in the RAM 104.
Then, read the shape data and perform the following step (a).

By (b), the coordinates of corresponding points on the top surface of the component and the top surface of the component are determined and sequentially stored in the RAM 106.

(a) Determine whether the number of divisions of two corresponding line elements is 2 or more. , 1, the end point of each line element is stored in the LLAM 105 as the corresponding point coordinate, and the next line element data is stored as L'5.
Take it.

(b) If the number of divisions is 2 or more, the coordinates of the division points of each line element are determined and used as corresponding point coordinates, which are stored in the RAM 106 7 and the next line element data is read. Oka, as shown in the 10th inscription, the number of divisions is M, and the coordinates of the two points are 1,000 it seven o' (xa
, Ya' + (xbs )'b) and the coordinates of the division points of the direct expansion connecting the two points xj, yj (j:=:1,2...
...M)ilLX3 = x3+ -F;, (x
b-xa)yj=yR+M(yb-ya). Also, as shown in Figure 10), θO is the center angle, r is the arc radius, M is the number of divisions, θ (0/%1) is the angular increment, and the straight line connecting the center Op and the arc starting point Os is The angle with the axis is ψ, and the shank is the coordinates of the dividing point xj, yj.

(J=L 2*...M)F'iX*=XB
, Ys=YB
θyj=Xj−1・5ino+Yj−1 fist■θ.

Once all the corresponding points have been calculated and stored through the above processing,
The processing unit 105 uses each corresponding point and formulas (6) to (9) and formula 01 to calculate Xi, Yi, Ui, Vi (i
=1.2. ...) and set this as No data in R.
, AM 106. As a result of the above, the top surface of the part and
'This means that No. data with a different F-plane shape has been created on the RAM 106.

After that, the No. data is passed through the tape punch 107 to υ tape 1.
08 to create a No. tape. Helmet.

It is also possible to directly read the No. data one block at a time from the RAM 106 and input it to the No. 201 device 201 to press it to perform the tapering process.

As described above, according to the present invention, even when the upper and lower surface shapes of parts are different, four-way taper processing can be performed, and the field of application of the wire cutting machine can be expanded. Even if there is a gap in the surface position on at least one of the top surface of the component and the XY program surface, or the bottom surface of the component and the UV lower guide movement surface, it is possible to perform taper machining in which the surface shape and bottom surface shape are different. , extremely useful.

[Brief explanation of drawings]

Figures 1 and 2 are explanatory diagrams of conventional taper processing, Figure 3 is an explanatory diagram of the relationship between the control surface and the component surface, and Figures 4 and 3f! 5
Figure 6 is an explanatory diagram of the wire passage on the XY programmable plane and the UV transfer plane when the L side shape of the part is a circle and the lower side shape of the part is square. FIG. 7 is a partial plan view of the parts, FIG. 8 is a block diagram of the present invention, FIG. 9 is a flowchart of FiNo data creation processing, and FIG. 10 is an explanatory diagram of divided Q-output. W It...Wire, WK...Part, US...Part top surface, 1) S...Part 1 side, FOS...XY program surface, SCS...UV) Guide movement surface 4th Times (8)

Claims (1)

[Claims] In a wire cut taper machining method in which the relative displacement Bψ between the wire and the workpiece is controlled by simultaneous two-axis control t7 on two control planes, and simultaneous four-axis control on the whole and t, and a predetermined taper process is performed on the workpiece, "Parts" - Surface and 1st
QIfIi control surface and a space between the two 1al on at least one of the set of the component lower surface and the second control surface.
/' When the tl is different, the top surface of the component and the component T 1r
Along the straight line connecting the corresponding points of ii, and il
The position of the projection point is determined by projecting the point on the set of control surfaces with the distance between the first and second control surfaces i:oV).
A wire cut chip card single force method characterized in that simultaneous four-axis control is performed using position data of corresponding points on the first and second control surfaces so that the wire simultaneously traces corresponding points on the first and second control surfaces. .