JPH0767849B2 - Thermal transfer method and apparatus for three-dimensional curved surface - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for performing foil transfer on a transfer surface having a three-dimensional curved surface by a hot stamp method, and an apparatus for carrying out the method.

[Conventional technology]

As a conventional thermal transfer device, as shown in FIG. 9, a workpiece a is placed on a jig receiver 51 mounted on a table 50, and a heated roll 52 is placed on the workpiece a via a transfer foil b. There is known a structure in which a foil is transferred to the surface of the work a by vertically pressing the work a. However, in this type of thermal transfer device, it is difficult to perform foil transfer on the surface of the work a having a three-dimensional curved surface. In this case, the lifted hot stamping machine appropriately divides the foil transfer site and double-presses it. The foil is thermally transferred by means of a hydraulic servo copying hot stamping machine, or the foil is thermally transferred by moving the work roll relatively by a hydraulic servo along a copying plate arranged in parallel with the work.

[Problems to be Solved by the Invention]

However, in the conventional device having the above-mentioned configuration, when the double punching is performed as in the former case, a joint between the foils is generated, and the quality is deteriorated due to a large variation in stamping. In the latter case, the hydraulic servo is used. There is a problem in that the equipment including the above is expensive and the drive unit of the apparatus has to be changed by changing the work, and the utility as a general-purpose machine is poor.

The present invention was created in view of the above problems, and enables hot stamping on a three-dimensional curved surface,
It is an object of the present invention to provide a thermal transfer device having a simple structure.

[Means for Solving the Problems]

Here, in the thermal transfer method and apparatus for a three-dimensional curved surface according to the present invention, the work 1 having a three-dimensional curved surface to be a foil transfer target means, as shown in FIG. 1 (a), a rotary shaft continuous with the facing portion 1a. The curved surface 1b around W has a different work curvature (arc A1 → A2) on the A side and curvature B (circle B1 → B2) on the B side, and forms a three-dimensional curved surface in a twisted state. pointing.

That is, according to the principle of the present invention, as shown in FIG. 1 (b), the foil transfer is performed only by the horizontal relative movement of the roll 2, and the face portion 1a is moved in the surface direction on the work mounting jig 3. The workpiece 1 can be regarded as an approximate two-dimensional curved surface by inclining (arrow θ) and selecting the rotation axis W ′ such that the curvatures on the A side and the B side approximately match.

[Action]

Therefore, as shown in FIGS. 2 (a) to 2 (d), the workpiece mounting jig 3 is heated and the linear movement between the facing portions 1a of the workpiece a under the roll 2 (arrow A) is performed. Part 1b
By rotating (corresponding to the arrow B) the corresponding portions with the rotation axis W'as an axis, the three-dimensional curved surface can be foil-transferred by the two-dimensional movement, and the structure of the device can be simplified. .

〔Example〕

According to the thermal transfer method for a three-dimensional curved surface according to the present invention, based on the above-mentioned principle, a work 1 having a foil transfer surface bent in a three-dimensional direction is inclined and supported in the surface direction so that the workpiece W is rotated around the axis W. Form an approximate quadric surface consisting of a curved surface portion 1b having parallel curved surfaces and a facing portion 1a continuous to the curved surface portion 1b, by linearly moving the facing portion 1a in the approximate quadric surface, and the curved surface portion 1b as described above. By rotating in the two-dimensional direction with the axis W as the rotation axis, the foil is continuously transferred onto the foil transfer surface having the three-dimensional curved surface, and the method is the work 1 bent in such a three-dimensional direction. This is realized by linearly moving and rotating in two dimensions the work mounting jig 3 having a work fitting groove for fitting the foil transfer surface in a substantially flush manner.

Next, an embodiment relating to a thermal transfer device for carrying out the thermal transfer method will be described with reference to FIGS.

FIG. 3 and FIG. 4 show the foil transfer state of the thermal transfer device. Reference numerals 11 and 11 denote a pair of guide rods which are horizontally installed on the upper surface of the machine base 12. The sliding block 13 slidably installed (arrow A) makes a linear motion along the guide rod 11 by the reciprocating drive cylinder 14 composed of a hydraulic cylinder inserted between the machine bases 12. Reference numeral 15 is a work mounting jig whose one end is rotatably mounted between the upper bearing projections 16 and 16 of the sliding block 13 via a rotary shaft 17, and the work mounting jig 15 is a fifth mounting jig. As shown in the figure, it is composed of a curved surface portion 15b having a curved surface which is formed around the rotary shaft 17 and is substantially parallel to the rotary shaft 17, and a face portion 15a which is continuous from the curved surface portion 15b. A work mounting surface having a work fitting groove 15c for fitting the foil transfer surface substantially flush is formed, and the swing end of the work mounting jig 15 and the sliding block 13 are formed.
Rotary drive cylinder 18 consisting of a hydraulic cylinder interposed between
Is rotated (arrow B) about the rotating shaft 17. Further, 19 is a machine base above the sliding portion of the work mounting jig 15.
A thermal transfer roll 19 made of silicon resin that is pivotally mounted to the machine frame 12a installed on the machine frame 12 via a pressure adjusting mechanism 20 in a vertical direction with respect to a suspension plate 21 fixed to the machine frame 12a. The thrust rods 30 and 30 projecting from both sides of the sliding frame 23 are externally fitted to the constructed guide rods 22 and 22, and the motor 2
A suspension block 25 having a thermal transfer roll 19 rotatably driven by 4 at the lower end thereof is connected to a sliding frame 23 via a vertical low-friction cylinder 26. The thermal transfer roll 19 is axially installed so that the roll surface is parallel to the foil transfer surface b of the work a.

FIG. 6 shows a pressure regulating mechanism, and 27 is the above machine frame.
A balancer that is connected to one end of a chain 29 that is wound around a pulley 28 that is axially installed on 12a, connects the sliding frame 23 to the other end, and keeps the low-friction cylinder 26 at a predetermined pressure through a precision air regulator 31. It becomes a structure that connects with.

Further, 32 is a foil supply mechanism that stretches and supplies the foil ribbon c along the lower surface of the thermal transfer roll 19, and the foil ribbon c is a machine frame.
It is wound around a foil ribbon roll 33 provided with a back tension motor (not shown) pivotally provided at one end of 12a, and after passing through the tips of the foil guide bars 34 and 35 fixedly installed on the machine frame 12a, The foil ribbon c is moved at a predetermined speed by being wound on a winding reel 37 which is configured to be rotationally driven by a winding motor 36 fixed to the other end of the machine frame 12a. Further, a foil pushing bar 39 is formed on the cylinder 38 which is located between the foil guide bar 34 and the thermal transfer roll 19 and extends and contracts in the vertical direction from the machine frame 12a side. Transfer surface b
The structure is adapted to the rotation of the workpiece mounting jig 15 in the two-dimensional direction.

The thermal transfer device having the above-described structure is shown in FIGS. 7 and 8 (a),
This is used when heat-transferring a foil to a foil transfer surface b having a three-dimensional curved surface shown by hatching, for example, an inner lens of an automobile lamp as a work a as shown in (b). Work fitting groove 15c of jig 15
To fit. When the apparatus is driven, the machine frame 12a descends, the foil guide bars 34 and 35 press the foil ribbon c so that the transfer foil contacts the work a, and at the same time, the thermal transfer roll 19 descends to move the foil transfer surface b of the work a. Press the transfer foil in contact with. At this time, the tips of the foil guide bars 34, 35 are on the foil transfer surface b.
Since it is located on the lower side, the adhesion of the transfer foil is improved.

The thermal transfer roll 19 is heated at a constant temperature required for transfer, and the balancer 27 and the precision air regulator 31 are used.
By this action, the foil ribbon c is pressed with a predetermined pressure set in advance.

At the same time as the thermal transfer roll 19 is pushed down, the reciprocating drive cylinder 14 extends, and the work mounting jig 15 slides along the guide rods 11 and 11 (to the right in FIGS. 3, 4, and 5). The transfer foil is transferred onto the face portion of the foil transfer surface b of the work a carried by the work mounting jig 15 by the movement. When the thermal transfer roll 19 reaches the end of the face transfer surface b, the reciprocating drive cylinder 14 stops and the foil pushing cylinder 38
Is extended, and the foil pushing bar 39 presses the foil ribbon c so that the transfer foil contacts along the curved surface direction of the foil transfer surface b of the work a, and at the same time, the rotary drive cylinder 18 is shortened and the work mounting jig 15 is moved. It revolves around the rotating shaft 17 as a central axis. By this rotation, the heat transfer roll is formed on the curved surface of the foil transfer surface b of the work a carried by the work mounting jig 15 via the foil ribbon c.
The 19 rolls under pressure, and the transfer is also applied to the curved surface portion to complete the transfer.

At the time of the transfer, the foil ribbon c is fed and moved by the winding motor 36 at the same speed as the moving speed of the foil transfer surface b of the work a, and the thermal transfer roll 19 is tilted at the same angle as the foil transfer surface b. Therefore, the foil ribbon c moves in close contact with the foil transfer surface b of the work a.

〔The invention's effect〕

As described above, according to the thermal transfer method and apparatus for a three-dimensional curved surface according to the present invention, the curved surface portion is approximated to the curved surface portion by carrying the workpiece substantially facing portion having the three-dimensional foil transfer curved surface with respect to the workpiece mounting jig. The next curved surface can be used, and the foil transfer can be easily performed by connecting the linear movement with respect to the facing portion and the rotational movement in the two-dimensional direction with respect to the curved portion, and as a result, the structure of the thermal transfer device can be simplified. It has an extremely excellent effect.

[Brief description of drawings]

1 (a) and 1 (b) are overall perspective views showing the relationship between a work and a work mounting jig showing the principle of the present invention, and FIGS. 2 (a) to 2 (d) are thermal transfer rolls of the work mounting jig. FIG. 3 is a schematic front view showing a state of foil transfer to a face part of a work, FIG. 3 is a schematic front view showing a foil transfer state to a face part of a work, and FIG. FIG. 5 is an enlarged front view showing the drive mechanism of the work attachment jig, FIG. 6 is a side view of the main part showing the pressure adjusting mechanism, and FIG. 7 shows the pressure contact state between the thermal transfer roll and the work. 8A is a perspective view showing an example of a work, FIG. 8B is a cross-sectional view of relevant parts, and FIG. 9 is a schematic front view showing a conventional thermal transfer device. 1 …… Workpiece, 2 …… Thermal transfer roll 3 …… Workpiece mounting jig, W, W ′ …… Rotating shaft 11 …… Guide rod, 13 …… Sliding block 14 …… Reciprocating drive cylinder 15 …… Workpiece mounting cure Tool, 15a …… Face part 15b …… Curved part, 17 …… Rotary shaft 18 …… Rotation drive cylinder, 19 …… Heat transfer roll 20 …… Pressure adjusting mechanism, 24 …… Motor 25 …… Low friction cylinder 31 …… Precision air regulator 32 …… Foil supply mechanism 34,35 …… Foil guide bar, 36 …… Winding motor 37 …… Winding reel a …… Work, b …… Heat transfer surface c …… Foil ribbon

Claims (5)

[Claims] 1. A curved surface portion having a curved surface parallel to the axis and a confronting portion continuous to the curved surface portion by carrying a work having a foil transfer surface bent in a three-dimensional direction in an inclined direction in the surface direction. And a three-dimensional curved surface is continuously formed by linearly moving the face portion in the approximate quadric surface and rotating the curved surface portion in the two-dimensional direction with the axis as the rotation axis. A thermal transfer method for a three-dimensional curved surface, characterized by transferring foil onto a foil transfer surface. 2. A work mounting jig having a work fitting groove for fitting a work having a foil transfer surface formed of a three-dimensional curved surface in a substantially flush manner, wherein the work is linearly moved and rotated in a two-dimensional direction. The thermal transfer method for a three-dimensional curved surface according to claim 1. 3. A work mounting jig for supporting a work having a foil transfer surface formed of a three-dimensional curved surface in a plane direction so as to form an approximate two-dimensional curved surface on an axis, and a work mounting jig. Work reciprocating drive means for moving the shaft in parallel, work rotating drive means for rotationally displacing the shaft, and a work pressure adjusting mechanism for the work carried by the work mounting jig, which is positioned above and below the work mounting jig so as to be vertically movable. Thermal transfer characterized by comprising a thermal transfer roll that is pressed down and heated at a predetermined pressure via a heat transfer roll, and a foil feeding mechanism that feeds and moves a foil ribbon stretched between the transfer roll and the work at a predetermined speed. apparatus. 4. The thermal transfer apparatus according to claim 3, wherein the thermal transfer roll is provided with an inclined axis parallel to the foil transfer surface of the work. 5. The pressure adjusting mechanism is structured such that a low friction cylinder is inserted between the thermal transfer roll and its suspension structure, and the air pressure supplied to the low friction cylinder is controlled to be constant by an air regulator. The thermal transfer device according to claim 3 or 4.