JPS5928184B2 - thermal transfer device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a thermal transfer device that is capable of continuous transfer to the outer circumferential surface of various three-dimensional objects. The object of the present invention is to achieve continuous and uniform transfer over the entire surface.

By the way, methods for thermally transferring various characters, figures, patterns, etc. onto the surface of articles are conventionally known and have been practiced for various articles.

However, among the devices that perform such thermal transfer, there is a device that uses a roll-shaped transfer body that enables continuous transfer, and is suitable for transfer that goes around the outer circumference of a three-dimensional object. It is prized as a gift. However, in conventional thermal transfer devices that use such a transfer roll, continuous transfer onto a cylindrical surface is difficult because the transfer pressure and transfer speed of the transfer roll against the transfer surface must be kept constant from beginning to end. Even if it is easy, continuous transfer to a transfer surface other than a cylindrical surface is difficult, and there remains room for improvement in this point. Therefore, the present inventor developed a thermal transfer device capable of continuous transfer even to transfer surfaces other than cylindrical surfaces, as disclosed in Japanese Patent No. 933559 (Japanese Patent Publication No. 53-912).
This has already been proposed in claim 1 of Patent Publication No. 4).

That is, this thermal transfer device is characterized by being equipped with a pressure control system for keeping the transfer pressure of the transfer roll against the transfer surface constant and a speed control system for keeping the transfer speed constant. The actual transfer pressure and transfer speed of the transfer roll against the transfer surface can be detected, and fluctuations thereof can be automatically corrected. However, such a known thermal transfer device assumes that the actual transfer width of the transfer surface is constant from beginning to end, so when transferring to a transfer surface where the actual transfer width is partially different, The transfer pressure, which is supposed to be kept constant by the pressure control system, actually fluctuates and acts on the transfer surface, making it impossible to achieve uniform and good transfer to the entire transfer surface. Be looked at.

That is, the pressure control system adopted in this thermal transfer device controls the total transfer pressure applied by the entire transfer roll to the entire width of the transfer surface, and controls the transfer pressure of the unit transfer width 9. It's not something you do. Therefore, for example, as shown in FIG. 1 and FIG.
When continuous transfer is performed on the surface in the direction of the arrow with the surface as the transfer surface opening, the actual transfer width is equal to the total transfer width W in each section of , V, and the width of the window C in the section of In the section 9, where the width a is subtracted (W-a), the width B and c of the window 2 and ho are subtracted (W-b-e), so using each section I,, V as a reference, When controlling the total transfer pressure of the transfer roller, if the transfer pressure of the unit transfer width in each section of 9 is excessive, when controlling the total transfer pressure based on each section of , I, . In other words, when the transfer pressure of the unit transfer width member 9 becomes excessive, the amount of heat transferred from the heated transfer roll to the transfer surface through thermal conduction through the transfer film becomes excessive, so that the pressure of the transfer film is applied. This causes undesirable elongation in the transferred area, causing cracks in the transfer foil and deformation of the transferred pattern, or excessive thermal deformation on the transferred surface. Furthermore, when the transfer pressure of the unit transfer width member 9 is insufficient, the amount of heat transferred by the above-mentioned heat conduction is also insufficient, resulting in insufficient transfer of the transfer foil from the transfer film to the surface to be transferred, and subsequent interference with other objects. The foil tends to peel off due to abrasion. The present invention addresses the above-mentioned problems, and even if the actual transfer width of the surface to be transferred is partially different, in order to uniformly and efficiently perform continuous transfer on the entire surface, it is possible to The total transfer pressure of the transfer roll on the transfer surface is corrected in a preprogrammed order and content based on the partial difference in the actual transfer width on the surface, so that the transfer pressure of the unit transfer width abutment v is always constant. This is how it was done. This will be explained in detail below with reference to the embodiment shown in FIG. In the figure, reference numeral 1 denotes a transfer roll made of a heat-resistant elastic material such as silicone rubber, which is rotatably supported at the tip of a support frame 3 that can move forward and backward along a guide 2, and is heated by an appropriate heat source (not shown). shall be carried out.

Reference numeral 4 denotes a hydraulic cylinder for pressing the transfer roll 1 against the surface to be transferred, and is adapted to move the support frame 3 forward and backward in conjunction with the piston 5.

However, the article A shown in FIGS. 1 and 2 to be transferred from a transfer film (not shown) is mounted on a rotating jig 6 for supporting and rotating the article, either one or two as shown in the figure. The individual holder 9 is attached so that its outer circumferential surface, which is the transfer surface opening, faces the transfer roll 1. A drive mechanism 10 interposed between the two is a hydraulic motor as one drive source. On the other hand, the above-described hydraulic cylinder 4 and the above-described hydraulic motor 10 are assumed to be driven by hydraulic pressure applied from an appropriate hydraulic source 11 via a servo valve 12 or 13.
2 and 13 are appropriately controlled by a pressure control section A or a speed control section B as described below, so that the transfer pressure and transfer speed during transfer are kept constant.

That is, the pressure control section A includes a pressure command circuit 14 for setting the transfer pressure, and a pressure detector 15 using a load cell or the like for detecting the actual transfer pressure via the rod 3.
and a strain amplifier 16, and a servo amplifier 17 for controlling the servo valve 12 by comparing the set value and the detected value, and applies the transfer roll 1 under a set transfer pressure. The speed control unit B includes a speed command circuit 18 for setting the transfer speed and a tachogenerator for detecting the actual transfer speed from the transfer roll 1. It is composed of a speed detector 19 used and a servo amplifier 20 for operating the servo valve 13 by comparing the set value and the detected value, and controls the transfer roll 1 at a set transfer speed. It is designed to rotate. However, what the above-mentioned pressure control section A can control is the total transfer pressure applied by the entire transfer roll 1 to the entire width of the opening of the transfer surface, and only when the transfer roll 1 is applied to the entire width of the transfer surface opening. It is not the transfer pressure of the unit transfer width 9 for the transfer surface opening.

Therefore, the pressure control unit A includes a correction controller 21 for outputting pressure correction commands according to the degree of difference in the actual transfer.
and a transfer position detector 2 for checking the progress of transfer.
A pressure correction section C consisting of 2 is added. That is, the above-mentioned correction controller 21 adjusts the total transfer pressure applied by the transfer roller 1 to the transfer surface B for one section when transferring to the article A as shown in FIGS. 1 and 2, for example. is P1,
A pressure correction command with contents such as P2 for the section, P3 for the section, P5 for the section V, and the like is output and given to the servo amplifier 17 of the pressure control section A. It is assumed that the content of the pressure command is corrected, and in that case, the total transfer pressure P1 to P5 in each section is as follows, where P is the total transfer pressure with respect to the total transfer width W of the transfer surface opening. The widths A, b, and c in each of these sections are set according to the actual transfer width, which varies depending on the presence or absence of window edges and ho.

The setting of the total transfer pressure for each section is programmed in advance based on the partial difference in the actual transfer width at the opening of the transferred surface, and is programmed in the correction controller 21 in the order from P1 to P5. shall be input and stored. The transfer position detector 22 is used to constantly check in which section the transfer to the transfer surface is currently being performed, and uses a pulse encoder, for example, to detect the transfer position from the rotation angle of the transfer roll 1. The correction controller 21 is driven by the detection signal to cause the controller to output the correction contents manually entered in advance for the section to which the current transfer position belongs. There is. That is, the correction controller 21
In response to the detection signals continuously given from 2, pressure correction commands are output one after another to the pressure control unit A according to the pre-stored order, based on the total transfer pressure set for the current transfer position. Therefore, the controller has a memory that sequentially stores the total transfer pressure set for each section mentioned above, and a transfer position detector 22 that responds to the transfer position sensor 22. It is appropriate to employ a combination with a microprocessor that sequentially reproduces the contents of the memory. In the above-described configuration, it is assumed that article A is now supported by rotating jig 6 as shown in FIG.

Then, the article A is rotated by the hydraulic motor 10 while being supported by the rotating jig 6. Further, a transfer roll 1 that performs transfer from a transfer film (not shown) to the surface to be transferred is pressed by a hydraulic cylinder 4 to the opening of the surface to be transferred, and is rotated as the object rotates. be done. However, in this case, the transfer pressure that should be exerted on the transfer surface B of the transfer roll 1, that is, the total transfer pressure P that the entire roll applies to the entire width of the transfer surface opening, is based on the case where there is no pressure correction section C in the transfer roller 1. When considering this, it is set by the pressure command circuit 14 of the pressure control unit A, and the servo valve 12 is operated based on the pressure command from the circuit, and the hydraulic cylinder 4 responds to the actual transfer target. The actual total transfer pressure applied to the transferred surface in this way is immediately detected by the pressure detector 15, and strain is applied to correct the difference from the pressure setting value. Since it is fed back from the amplifier 16 to the servo amplifier 17, the total transfer pressure P is exactly equal to the initially set desired total transfer pressure P. Therefore, when the transfer surface opening is, for example, the outer peripheral surface of an article having a circular cross section, the total transfer pressure of the transfer roll 1 against the surface is, of course, equal to the set value and constant from beginning to end.
Even when the outer circumferential surface of an article has a non-circular cross-sectional shape, fluctuations in the total transfer pressure due to the shape can be corrected by the feedback-based correction function of the pressure control unit A as described above. As a result, the total transfer pressure of the transfer roll against the transfer surface is equal to the set value and remains constant from beginning to end.On the other hand, the transfer speed at this time rotates to follow the rotation of the article A. It is determined by nothing but the circumferential speed of the transfer roll 1, and therefore by the rotational speed of the article and the radius of rotation of the roll contact area on its outer peripheral surface.

However, this transfer speed is determined by the speed command circuit 1 of the speed control section B.
8, the servo valve 13 is operated based on the speed command from the circuit, and the hydraulic motor 10 responds to rotate the article A, thereby giving 49 degrees. -A? 〉d)
P×) RI Tsume d Sai Must Be Jf Length 4 Good Pattern 4 * The red printing speed is immediately detected by the speed detector 19 and fed back to the servo amplifier 20 in order to correct the difference with the speed setting value. , exactly equal to the initially set desired transfer rate. Therefore, if the surface to be transferred is, for example, the outer peripheral surface of an article with a circular cross section, the transfer speed of the transfer roll 1 to the surface is, of course, constant and equal to the set value from beginning to end. Even when the outer circumferential surface of an article has a The transfer speed of the transfer roll is now equal to the set value of 9 and is maintained constant throughout. When the transfer performed in this manner is for an article A as illustrated in FIGS. The total transfer pressure P is corrected as follows based on the partial difference in the actual transfer width at the opening of the transfer surface.

Assuming that transfer is currently being performed on the section I at the transfer surface opening, the correction controller 21 at this time sends a pressure correction command to the pressure control unit A to set the total transfer pressure to P1. The direction is output and the control system is made to follow it.
Next, when the transfer to the transfer surface B progresses from the section I to the section I, this is detected by the transfer position detector 22, and the correction controller 21 outputs a pressure correction command to set the total transfer pressure to P2. and the pressure control section A is made to follow this. Similarly, as the transfer to the transfer surface B progresses to each section of ,V, the correction controller 21 outputs the total transfer pressure as P, ,P,
, P5 are sequentially output, and the pressure control section A is made to follow each of them. However, the total transfer pressure P1 to P5 corrected based on the pressure correction command from the pressure correction section C is different from each section 1 of the transfer surface opening as described above.
Since it is set based on the actual transfer width at −V, the transfer pressure P of the unit transfer width abutment v in each of these sections is
1/P2,P,′,P! , becomes. That is, the transfer pressure of the unit transfer width abutment 9 against the opening of the transferred surface is maintained constant throughout even if the actual transfer width of the surface is partially different. As described above, in the case where the outer peripheral surface of a three-dimensional article is used as the transfer surface, the total transfer pressure and transfer speed on the transfer surface are basically maintained constant from beginning to end, while
The total transfer pressure is corrected based on the partial difference in the actual transfer width, so that the transfer pressure of the unit transfer width 9 can be maintained constant from beginning to end. Not only can continuous transfer be easily carried out on the outer circumferential surface of the surface, but also the continuous transfer on the surface can be expected to be uniform and good even if the actual transfer width is partially different.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing an example of the invention, FIG. 2 is a developed plan view, and FIG. 3 is a system diagram showing an embodiment of the invention. DESCRIPTION OF SYMBOLS 1... Transfer roll, 4... Hydraulic cylinder, 6 one rotation jig, 10... Hydraulic motor, 12, 13... Servo valve 14... Pressure command circuit, 15... Pressure detector ,1
6... Strain amplifier, 17... Servo amplifier,
18... Speed command circuit, 19... Speed detector, 20
...Servo amplifier, 21...Correction controller, 22...
・Transfer position detector, A...target article, mark...transferred surface, A...pressure control section, B...speed control section, C...
Pressure correction section.

Claims (1)

[Claims] 1 It has a transfer roll that can move forward and backward with respect to the transfer surface of the target article, a cylinder that presses the roll against the transfer surface, a rotating jig that supports the article while rotating it, and a motor that rotates it. And in the above cylinder,
A pressure command circuit that sets the total transfer pressure on the transferred surface of the transfer roll and a pressure detector that detects the actual total transfer pressure, and the set value of the former and the detected value of the latter are compared to determine the actual total transfer pressure. The motor is equipped with a pressure control section consisting of a servo amplifier that maintains the transfer speed according to the set value, and the motor includes a speed command circuit that sets the transfer speed of the transfer roll, a speed detector that detects the actual transfer speed of the roll, In a configuration equipped with a speed control unit including a servo amplifier that compares the former set value and the latter detected value and maintains the actual transfer speed as the set value, the actual transfer width on the transfer surface is A correction controller that stores in advance the individual total transfer pressure set for each part based on the local difference according to the transfer order, and a correction controller that constantly detects the current transfer position on the transfer surface and adjusts the position. A pressure correction section is added to the pressure control section, and includes a transfer position detector that sequentially outputs a pressure correction command based on the preset total transfer pressure from the correction controller to the pressure control section. . A thermal transfer apparatus, wherein the content of a pressure command given to the cylinder from a pressure control section is corrected by a pressure correction command from the correction controller.