JPS633788Y2 - - Google Patents

Description

[Detailed description of the invention] The invention is based on the design of a plastic sheet with a pattern printed on it.The edge of a continuous sheet in the form of a long strip is held by a feeding chain so that each design can be molded to fit the mold precisely. This relates to a positioning device for a pattern-printed plastic sheet molding machine that feeds a pattern-printed plastic sheet by a length that is an integral multiple of A continuous belt-shaped plastic sheet with a pattern is fed by a feed chain that bites the edge of the edge, and a pulse motor driven by the feed chain, which is driven by a set number of pulses slightly greater than the required feed amount of the chain. , a pulse generator that converts the rotation speed of the feed rotation unit into a digital pulse signal, subtracts a set pulse value of the pulse motor from the generated pulse signal train, and stops the motor when the deviation value is zero; and the printed pattern. A mark sensor facing the passage area of the pulse motor is provided, and a first motor stop signal is sent out in relation to when the set pulse value of the pulse motor becomes a subtractive value immediately before stopping, and that first signal and the mark sensor This positioning device for a pattern-printed plastic sheet molding machine is characterized in that a pulse motor is commanded to stop by outputting a logical product of mark detection signals, and the printing pattern is aligned with the molding section by the stoppage.

In a plastic sheet forming machine, a continuous plastic sheet is printed with vertical and horizontal designs that match the forming part of the thermoforming device, and the sheet feeding device installed in the forming machine is adjusted to a value slightly greater than the required feed rate. The servo feeding device is driven by a pulse motor set to A device is known in which the deviation value is subtracted based on the number of generated pulses and the sheet feeding device is stopped when the deviation value becomes zero. Since the feeding device feeds a slightly large amount of pattern-printed plastic sheets, a master sensor is installed that detects the pattern when the feeding stops, and when the sensor detects a white area between the printed patterns on the plastic sheet, the sensor detects the pattern. The next feed is controlled by correction, and when the sensor detects a printed pattern, the next feed amount is slightly corrected in the direction of decrease. However, although the excessive feed amount of this servo feeding device is small, it is only possible to correct the next feed amount.

In view of the above, the present invention improves the feed amount of the pattern-printed continuous sheet by the feed chain each time so that the printed pattern matches the forming part of the thermoforming device, and improves the feed amount of the conventional feed amount by modifying the conventional device. In comparison, the purpose is to enable more precise alignment of printed designs.

An embodiment of the present invention will be described in the next section.

The attached drawing shows a known sheet forming machine whose main parts are a thermoforming device 2 and a feeding chain 4 that feeds a continuous band-shaped plastic sheet a with a pattern printed on it by clamping both edge ends of the same with an arbitrary clamp device. As shown in FIG. 2, a pattern-printed plastic sheet a is provided with blocks c printed with a plurality of printed patterns b in the vertical and horizontal directions, and each pattern b is aligned with the thermoforming device. The forming portions 3 are arranged in the column direction and the row direction.

The feeding chain 4 serves as a feeding device for feeding the pattern-printed plastic sheet a on which the printed pattern b is printed, and the feeding chain 4 is driven by a pulse motor 5. 6 is a pulse generator (known in the art) that converts the rotation speed of the feed rotation unit driven by the pulse motor 5 into a digital pulse signal; 7 is a feed chain 4;
The pattern-printed plastic sheet a is fed in the direction of the thermoforming device 2 by the
It is a mark sensor that detects the passing of the pattern b printed on the mark sensor, and has a function of optically detecting the printed pattern b of each individual in the column. In this example, the pattern b
The pattern _b1 of each block c is detected.

The pulse motor 5 is set to a pulse value slightly larger than the required feed amount L of the pattern-printed plastic sheet a, so as not to cause a shock at the beginning of the feed and to avoid a sudden stop at the end of the feed. As is clear from the speed curve in Fig. 3, the pulse array of the set pulse number has a pulse array zone in which the number of rotations is increased sequentially at the beginning, a pulse array zone that provides a predetermined high number of rotations, and a pulse array zone at the end. and a pulse array zone in which the rotational speed is sequentially decreased.

The pulse signal train generated by the pulse generator 6 is
The set pulse value of the motor 5 is subtracted, and when the deviation value is zero, the motor is stopped. However, if the mark sensor 7 is in good condition, the pulse motor 5 is
stops before being stopped by the pulse signal from the pulse generator.

When the intermittent feed of the pattern printed plastic sheet a is 500 mm and the feed amount per pulse of the setting pulse signal is set to 0.1 mm, the first motor stop signal P corresponds to the feed amount of 5 mm at the end of the feed. occurs in the interval. The interval of the feed amount of 5 mm is also the feed amount between the blank portion of the sheet between the patterns b and _b1 and the end of the pattern b, which the mark sensor 7 detects.

When the mark sensor 7 detects the passing of the symbol b ₁ in the above-mentioned standby state, the theoretical product of the first motor stop signal and the symbol detection signal in an AND circuit, etc. is established, and a motor stop signal is sent to the pulse motor 5.
to stop. The printed pattern plastic sheet a, which detects the pattern _b1 and stops, accurately aligns each pattern b with each molding section 3 of the thermoforming device 1 using its stopping position.

A counter 8 subtracts the set number of pulses of the pulse motor 5 by the pulses generated by the pulse generator 6. In this embodiment, when the pulse motor 5 decelerates by sequentially going to the pulse sequence zone of deceleration and one feed approaches the end, that is, when the subtraction value is reached immediately before the stop, the motor stop first signal is P
is sent out to wait for the detection signal input from the mark sensor (see Fig. 3).

The device of the present invention uses a pulse motor 5 set with a pulse value slightly larger than the necessary feed amount to feed a continuous strip-shaped plastic sheet a with a pattern printed on it in the direction of a thermoforming device 2 through a feeding chain 4, and a mark sensor 7 prints the pattern. The system is configured to detect the pattern b and send out a detection signal, and at the same time apply it to the pulse motor 5 as a stop command signal to stop the feeding of the pattern-printed plastic sheet a. Even if there is
This produces an effect of accurately aligning the printed pattern b with the forming part of the thermoforming device 2 without accumulating errors in the feed amount, and achieves extremely reliable alignment between the printed pattern b and the forming part 3. It has an effect that can be used.

[Brief explanation of the drawing]

The attached drawings show one embodiment of the present proposal, and Fig. 1 is a schematic side view, Fig. 2 is a plan view of the pattern-printed plastic sheet a and the feeding chain 4, and Fig. 3 is a diagram showing the feeding speed. It is a curve diagram. 1... Sheet forming machine, 2... Thermoforming device, 3...
...Molding section, 5...Pulse motor, 6...Pulse generator, 7...Mark sensor, a...Design printed plastic sheet, b, b ₁ ...Printed design.

Claims (1)

[Scope of utility model registration request] For a thermoforming device equipped with molding sections arranged in columns and rows, a feeding chain that feeds a continuous belt-shaped plastic sheet with a printed pattern corresponding to the molding sections by biting the rim; A feed chain-driven pulse motor is driven by a set number of pulses slightly greater than the required feed amount of A pulse generator that subtracts the set pulse value of the pulse motor and stops the motor when the deviation value is zero, and a mark sensor facing the passage area of the printed pattern are provided, and the set pulse value of the pulse motor is set immediately before stopping. A first motor stop signal is sent out in relation to the subtraction value, and the AND output of the first signal and the mark detection signal of the mark sensor is used to command the pulse motor to stop, and this stop causes the printed pattern to be formed as described above. A positioning device for a pattern-printed plastic sheet molding machine, which is characterized by aligning parts.