JPH0358900B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a heating device in a vacuum forming machine used to heat-form sheets made of synthetic resin, expanded polystyrene, or the like.

BACKGROUND TECHNOLOGY Generally, when forming a sheet, the sheet is sequentially unrolled from a sheet roll, fed intermittently in predetermined size increments, heated once by a heating device during the movement path, and then formed into a predetermined shape by a forming device. It is sent to the next process. By the way, when some kind of trouble occurs during sheet forming and the machine is to be inspected and repaired, or the mold of the forming equipment is replaced, etc., the sheet will be overheated if the heating device is left running, so it is normal to turn off the heating. Turn off the power to the device, but even when the power is turned off, its radiant heat remains at a very high temperature (approximately 500
600°C), the radiant heat caused the sheet to heat and soften and sag under its own weight, causing the sagging part to come into contact with the lower heater and cause the sheet to burn.

Therefore, conventionally, when inspecting and repairing a machine or replacing a mold, a device such as the one shown in FIG. 1 was used to move the heater out of the sheet transport path. That is, in the same figure, 1 is the machine frame of the vacuum forming machine, 2
is a heating device comprising a sheet 3 which is intermittently transported by an appropriate transport means, and an upper heater 4 and a lower heater 5 installed at predetermined positions in the transport path of the sheet 2. 6 is a carrier having a U-shaped cross section on which the heaters 4 and 5 are mounted; 7 is a rail installed perpendicular to the transport path of the sheet 2; on this rail 7, the carrier 6 can be moved via wheels 8; Place it. 9 is an air cylinder for moving the carrier 6. When inspecting and repairing the machine or replacing the mold, the air cylinder 9 is activated to extend the rod 10 and push the carrier 6 out of the machine frame 1 as shown by the dashed line.When the work is completed, the carrier 6 is Move into machine frame 1.

Further, there is a heating device described in Japanese Patent Publication No. 39-2068, which is capable of preventing excessive heating of the sheet. This is to retract the divided heaters in symmetrical directions on both sides by reciprocating the divided heaters in a straight line in the horizontal direction or by reciprocating them in an arc shape.

Problems to be solved by the invention However, the above conventional heater 4,
5 outside the machine frame 1, a temporary evacuation space for the carrier 6 is required, which requires a larger installation space and places restrictions on the installation location.
In addition, since the heating time of the sheet 2 is within a few seconds, even if the power to the heaters 4 and 5 is turned off and the heaters 4 and 5 are evacuated outside the machine frame 1, the hanging portion 2a of the sheet 2 is heated during the movement. The sheet 2 was excessively heated by the radiant heat of the heater 5, causing the hanging portion 2a to sag further, and the sheet 2 to catch the end portion 5a of the heater 5 moving outward, causing the sheet 2 to burn. Conversely, heaters 4 and 5 are on machine frame 1.
When the engine moves inwards, the edge portion 2a of the seat 2 is overheated, resulting in seat loss upon restart.

In addition, according to a known technology described in Japanese Patent Publication No. 39-2068, which retracts the heater in both directions by moving it back and forth in a straight line in the horizontal direction, even though the heater is divided, the machine frame is Temporary evacuation space is required for the split heater on both sides, which limits the installation location, and since the split heater moves horizontally, the stroke time during movement causes uneven heating, causing the seat to be exposed to the radiant heat of the heater. Therefore, there is a problem of excessive heating. On the other hand, according to a type in which the split heater moves back and forth in an arc shape, the split heater is attached to a right triangular frame member that rotates around a pivot point, and when retracting in both directions, the split heater The outer apex of the frame member separates from the sheet at the same time as the frame member moves, but the inner right-angled apex of the frame member moves in an arc shape along the sheet, so uneven heating occurs due to the stroke time of the inner right-angled apex, and the sheet moves away from the frame member. The radiant heat of the split heater from the inside right angle part causes excessive heating from both the top and bottom surfaces, which causes the sheet to droop further, and when the frame member rotates, the inside right angle top part of the frame member hits the hanging sheet. The sheet may catch fire.

An object of the present invention is to prevent excessive heating of the sheet and to make effective use of the installation space.

Means for Solving the Problems The present invention was proposed in view of the above problems, and is installed in the transport path of sheets that are intermittently fed by a predetermined size, and can be raised and lowered in a direction perpendicular to the machine frame. an upper heater mounted on the seat, a lifting means for raising and lowering the upper heater, and a lower heater comprising a pair of split heaters installed opposite the upper heater and divided at the center position in the width direction of the seat. , a parallel link mechanism that is swingably attached to the machine frame and supported so that each divided heater of the lower heater can be symmetrically retracted outward diagonally downward while keeping it in a horizontal position; It is equipped with a swinging means for moving.

Function During machine maintenance and inspection, the upper heater moves upward vertically while maintaining its horizontal position, and at the same time, the divided heaters of the lower heater move symmetrically outward diagonally downward while maintaining their horizontal position. Move to evacuate. Therefore, uneven heating does not occur during movement of the heater, and it is possible to reliably prevent the sheet from being excessively heated by the radiant heat of the heater.

Embodiment FIGS. 2 to 5 show embodiments of the present invention. In the same figure, 11 is a machine frame of a vacuum forming machine, and 12 is a transfer device 1 that sequentially repeats the sheet roll winding as appropriate.
3, the sheet is intermittently transported by a predetermined size; 14 is a heating device consisting of an upper heater 15 provided in the transport path of the sheet 12; and a lower heater 16 installed symmetrically with the upper heater 15; The upper heater 15 is supported by an elevating means a so as to be vertically movable, and the lower heater 16 is divided at the center position in the width direction of the sheet 12, and the divided heaters 17a and 17b are moved in a fan-shaped trajectory in both directions. It is supported so that it can be moved while drawing. In the elevating means a of the upper heater 15, 18 is a rotating shaft rotatably supported on the machine frame 11 in the width direction via brackets 19, 19, and this rotating shaft 18 has reverse threads 20a, 2
0b is formed, and an operating handle 21 is attached to one end thereof. Reference numerals 22 and 22 denote suspension bodies that are screwed into the right-hand screw 20a and left-hand screw 20b of the rotating shaft 18 so as to be movable in the axial direction. 23, the upper ends of levers 24, 24 are rotatably pivoted and suspended, and the lower ends of the levers 24, 24 are rotatable on a mounting plate 26 attached to the upper heater 15 via a bracket 25. The heater 15 is suspended by attaching it to the heater 15. 27, 27 are wheels rotatably supported on the shaft portions 23, 23 on both sides of the suspension bodies 22, 22, 28, 28 are support frames fixed to the machine frame 11 in the width direction; 29; , 29 are rails fixed to the support frames 28, 28, and the wheels 27, 27 of the suspension bodies 22, 22 are placed on the rails 29, 29. Reference numeral 30 indicates a guide rod fixed upright at the corner of the mounting plate 26 of the upper heater 15, and 31 indicates a guide rod 30.
The guide rod 3 is a guide cylinder fixed to the support frames 28, 28 in correspondence with the guide cylinder 31.
to be slidably inserted into the

32a and 32b are brackets 3 at four symmetrical positions in the width direction of the lower horizontal frame 33 of the machine frame 11.
8 which is rotatably pivoted upright via 4a and 34b.
The split heaters 17a and 17b of the lower heater 16 are pivoted to the upper ends of the links 32a and 32b via brackets 41a and 41b, respectively, to form parallelogram link mechanisms 35a and 35b. The heaters 17a and 17b are supported so that they can be symmetrically retracted diagonally downward to the outside while being maintained in a horizontal position. Reference numerals 36a and 36b are transmission shafts rotatably bridged between the inner brackets 34a and 34b, and the above inner links 32a and 32b.
In order to rotate simultaneously, the base ends of the links 32a and 32b are fixed to the shaft ends of the respective transmission shafts 36a and 36b, and levers 37a and 37b are fixed to the substantially central portions of the transmission shafts 36a and 36b, respectively. and make them stand up. b is the above-mentioned parallelogram link mechanism 35
This is a swinging means for swinging a and 35b. In the swinging means b, 38a and 38b are air cylinders installed at symmetrical positions on both sides of the machine frame 11 via brackets 39a and 39b.
The ends of the rods 40a, 40b of 8a, 38b are connected to levers 37 which are supported by the transmission shafts 36a, 36b.
a, 37b, and the air cylinder 38
The above-mentioned links 32a, 32 are activated by the operation of a, 38b.
By rotating b, the divided heaters 17a and 17b
Move diagonally downward on both sides.

Next, the operation of the present invention will be explained as follows.

If it becomes necessary to inspect or repair the machine or replace the mold during the molding of the sheet 12, the heating device 14
After turning off the power, the upper and lower heaters 15 and 16 are moved respectively. That is, when moving the upper heater 15, the operation handle 21 is operated to rotate the rotating shaft 18 in a predetermined direction, and the suspension members 22, 2 are screwed into the right-hand screw 20a and the left-hand screw 20b.
2 is moved symmetrically outward in the axial direction. The above hanging body 2
As the levers 2 and 22 move, the levers 24 and 24 tilt outward about the lower end pivot portions as fulcrums, and the upper heater 15 is pulled upward and separated from the seat 12 while being held in a horizontal position. Thereby, the sheet 12 will not be heated and softened by the radiant heat of the upper heater 15, and excessive heating of the sheet 12 can be prevented. It goes without saying that the rotating shaft 18 may be rotated electrically instead of manually using the operating handle 21.

The lower heater 16 is moved simultaneously with the movement of the upper heater 15. That is, the air cylinder 38
a, 38b is activated and the rods 40a, 40b are retracted, the levers 37a, 37b are moved to the transmission shaft 36.
The inner links 32a and 32b, whose base ends are fixed to the transmission shafts 36a and 36b, rotate outward about the levers 37a and 36b.
a, 37b, the inner and outer links 32a, 32b rotate around their lower end pivot points as fulcrums, and the parallelogram link mechanism 35a is configured in conjunction with the split heaters 17a, 17b. ,3
5b, the divided heaters 17a and 17b are moved in a fan-shaped trajectory from the center position in the width direction of the seat 12 and moved separately in both directions while being maintained in a horizontal position, and are held at predetermined positions diagonally downward on both sides. be done. In addition, at this time, the divided heaters 17a, 1
7b does not come out of the machine frame 11.

When inspection and repair of the machine or mold replacement is completed, the upper heater 15 rotates the rotary shaft 18 in the opposite direction and lowers it, and the divided heaters 17a and 17b of the lower heater 16 are operated by the air cylinder 38a,
38b is actuated to extend the rods 40a, 40b, move them inwardly, and return them to their original positions.

Effects of the Invention In the present invention, the upper heater is supported so as to be vertically movable, and each of the divided heaters of the lower heater is supported so as to be movable symmetrically toward the outside and downward.
The heater is always supported within the machine frame of the molding machine and never comes out of the machine frame. Therefore, the installation space is about half that of the conventional heater, and there are no restrictions on the installation location. Moreover, during maintenance and inspection of the machine, the divided heaters of the upper and lower heaters are moved upward and diagonally downward on both sides at the same time while being kept in a horizontal position, so there is no uneven heating, and the heaters are It is possible to reliably prevent the sheet from being excessively heated by heater radiant heat during movement.

In addition, each divided heater of the lower heater moves separately from the center position in the width direction of the sheet to the left and right, so even if the sheet sags due to heating and softening, the sheet will not be overheated. Even if the sheet hangs down significantly, there is no heater heat source below it, so there is no risk of the sheet burning. In particular, the lower heater, which is the main cause of overheating, is a split type, but the upper heater, which does not have much effect on overheating, is a non-divided type that can be moved up and down in the vertical direction, resulting in lower manufacturing costs. , can be provided at low cost.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of a conventional heating device. Second
3 is a side view of the upper heater, FIG. 4 is a side view of the lower heater, and FIG. 5 is an explanatory diagram of the operating state of the lower heater. 11...Machine frame, 12...Seat, 14...Heating device, 15...Upper heater, 16...Lower heater, 17a, 17b...Divided heater, 35a,
35b... Link mechanism, a... Lifting means, b...
Swinging means.

Claims (1)

[Claims] 1. An upper heater that is installed in the transport path of sheets that are intermittently fed by a predetermined size and that is mounted on the machine frame so that it can be raised and lowered in a vertical direction, a lifting means that moves the upper heater up and down, and the upper heater. A lower heater consists of a pair of split heaters that are installed facing each other and are divided at the center position in the width direction of the seat, and a lower heater that is swingably installed on the machine frame and that each split heater of the lower heater is horizontally A heating device for a vacuum forming machine, comprising: a parallel link mechanism that is supported so as to be symmetrically retracted and moved diagonally downward to the outside while maintaining the posture; and a swinging means for swinging the parallel link mechanism.