JP2011104940A - Vacuum forming apparatus and vacuum forming method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To make a resin sheet adhered on a substrate without forming wrinkle or unevenness. <P>SOLUTION: A resin sheet 117 is made to face a substrate 115 loaded on a mold 102 while clamping in the long side edge of rectangular resin sheet 117 with first and second clamp members 201, 202 and in the short side edge with a third clamp member 203. The second clamp member 202 is unclamped from the resin sheet 117 after heat softening the clamped resin sheet 117. The mold 102 moves to approach the resin sheet 117. During the process, motion of the mold 102 is transmitted to the first clamp member 201 through a support member 106, a base member 204, a slide body 207, etc. and the first clamp member 201 moves to distort the resin sheet 117. The resin sheet 117 thereafter is mold clamped while contacting the substrate 115 and vacuum formed. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a vacuum forming apparatus and a vacuum forming method used for closely attaching a resin sheet to a base material such as a bumper of an automobile.

  FIG. 8 is a schematic diagram for explaining an example of a conventional vacuum forming method as a premise of the present invention. In a vacuum forming apparatus 901 shown in FIG. 8A, a molding die 903 is attached to a table 902. The table 902 is provided with a hole 902a for vacuuming AB (FIG. 8D). Further, a base material 904 (for example, a bumper of an automobile) is mounted on the upper surface of the molding die 903. A presser box 905 is disposed above the molding die 903. The presser box 905 is a box whose bottom surface is open. A vent 906 is open on the side surface of the presser box 905. Both the table 902 and the presser box 905 move up and down. Further, the vacuum forming apparatus 901 includes a gripping device 908 that positions a flat resin sheet 909 between the molding die 903 and the presser box 905 and grips the resin sheet 909 horizontally.

  When the resin sheet 909 is brought into close contact with the base material 904 using such a vacuum forming apparatus 901, first, the heater 910 moves to a position where the resin sheet 909 held by the holding apparatus 908 is sandwiched, The sheet 909 is heated (FIG. 8B). Subsequently, the heater 910 retreats from the position where the resin sheet 909 is sandwiched, and the table 902 and the molding die 903 are raised to bring the base material 904 into contact with the resin sheet 909 softened by heating (FIG. 8C). Thereafter, the presser box 905 is lowered to close the gap between the presser box 905 and the molding die 903, and vacuuming AB is performed between the molding die 903 and the resin sheet 909, thereby forming the molding die 903 and the resin sheet 909. Are brought into close contact with each other (FIG. 8D). At the same time, the compressed air AA blows in the compressed air AA from the vent 906, and the resin sheet 909 is compressed and formed (FIG. 8D). Subsequently, the table 902 and the molding die 903 are lowered, the presser box 905 (not shown in FIG. 8E) is raised, and the gripping device 908 releases the resin sheet 909 (FIG. 8E). Thereafter, the end portion of the resin sheet 909 protruding from the base material 904 is cut off, and a finished product is completed.

  As described above, in the vacuum forming method described above, the base material 904 is moved up and down with respect to the resin sheet 909 extending in the horizontal direction, and the base material 904 is brought into close contact with the resin sheet 909. For this reason, in the base material 904, a region (region Q1 shown in FIG. 8 (c)) that is greatly inclined with respect to the resin sheet 909 and a region (FIG. 8 (c)) that faces parallel to the resin sheet 909. In the region Q2) shown, the thickness of the resin sheet 909 is different.

  On the other hand, vacuum forming is performed after the resin sheet is deformed according to the shape of the base material. For example, in Patent Document 1, a support member 22 that protrudes from a clamp member 21 that holds the edge of the resin sheet J and supports the lower surface of the resin sheet J is provided on a desired portion (center portion) of the resin sheet J that is desired to have a slack. B) extends along both sides, and a pair of auxiliary holding means 20 composed of a clamp member 21 and a support member 22 are moved close to each other to give a slack to the central portion B.

Japanese Unexamined Patent Publication No. 2009-039862 (FIGS. 3, 6, and 8)

  In the vacuum forming method described in Patent Document 1, a part of the edge of the resin sheet is heated without being fixed, and the part is suspended and deformed by its own weight. For this reason, unevenness occurs in the thickness of the resin sheet, and wrinkles occur in the resin sheet.

  An object of the present invention is to make a resin sheet adhere to a substrate without unevenness without causing wrinkles.

  The vacuum forming apparatus of the present invention includes a molding die for mounting a base material, a first clamp part for clamping a part of one opposing edge of a rectangular resin sheet, and one opposing edge of the resin sheet. A second clamp part that clamps at least a part of the resin sheet, and a third clamp part that clamps the other opposing edge part of the resin sheet, and clamps each edge part of the resin sheet to provide the resin. A resin sheet gripping part that causes the sheet to face the substrate, a heating part that heats and softens the resin sheet clamped by the first clamp part, the second clamp part, and the third clamp part, and A conveying unit that moves at least one of the molding die and the resin sheet to move the resin sheet closer to and away from the base material, and transmits the movement of the molding die and the resin sheet that are moved closer to and away from the substrate by the conveying unit. A transfer unit configured to move the first clamp unit and to deform the resin sheet in a state of being clamped by the first clamp unit and the third clamp unit and unclamped by the second clamp unit; A vacuum forming part for clamping and vacuum forming the resin sheet in contact with the substrate by the part.

  The vacuum forming method of the present invention includes a first clamp part that clamps a part of one opposing edge part of a rectangular resin sheet, and a first clamp part that clamps at least a remaining part of the one opposing edge part of the resin sheet. Each of the edges of the resin sheet is clamped by a resin sheet gripping portion provided with a clamp portion of 2 and a third clamp portion for clamping the other opposing edge of the resin sheet, and mounted on a molding die A step of causing the resin sheet to face the substrate, a step of heat-softening the resin sheet clamped to the first clamp portion, the second clamp portion, and the third clamp portion, and the heat-softening step. A step of unclamping the second clamp portion from the resin sheet, and moving at least one of the molding die and the resin sheet to move the resin sheet closer to and away from the substrate. A step of transmitting the movement of approaching and separating between the molding die and the resin sheet to the first clamp part to deform the heat-softened resin sheet; and the resin sheet in contact with the substrate. And clamping and vacuum forming.

  According to the present invention, the resin sheet deforms while the resin sheet and the base material are close to and away from each other, and after the deformation, the resin sheet comes into contact with the base material to perform clamping and vacuum forming. , Without causing wrinkles, it can be adhered to the substrate without unevenness.

It is a front view of a vacuum forming apparatus. It is a side view of a shaping die. (A) is a front view of a resin sheet holding part. (B) is a top view of a resin sheet holding part. (A) is a top view which shows a part of resin sheet holding part. (B) is a front view which shows a part of resin sheet holding part. (A)-(c) is a schematic diagram which shows the flow of the vacuum forming method. (A)-(c) is a schematic diagram which shows the flow of the vacuum forming method. (A) is a perspective view of the vacuum forming apparatus showing a state immediately before the contact body comes into contact with the base member before the deformation of the resin sheet. (B) is a perspective view of the vacuum forming apparatus which shows a mode after a contact body contacts a base member and a resin sheet deform | transforms. It is a schematic diagram for demonstrating an example of the conventional vacuum forming method used as the premise of this invention.

  One embodiment will be described with reference to FIGS. For convenience of explanation, this embodiment is referred to as a first embodiment. FIG. 1 is a front view of the vacuum forming apparatus 101. The vacuum forming apparatus 101 is for forming a resin sheet 117 in close contact with a base material 115 such as an automobile bumper mounted on the molding die 102. The vacuum molding apparatus 101 includes a molding die 102 and a resin sheet gripping portion. 103, a heater 104 as a heating unit, a presser box 105, a support member 106, and a cylinder device 107.

  The molding die 102 has a convex shape protruding upward, and a convex surface 111 is formed on the upper surface. The molding die 102 is placed on the table 112. The table 112 is provided with a hole 114 for evacuation by the suction device 113. A base material 115 is mounted on the convex surface 111 of such a molding die 102. The suction device 113 and the hole portion 114 constitute a vacuum forming portion 113a.

  The presser box 105 is disposed above the molding die 102. The presser box 105 is a box whose bottom surface is open. A vent hole 116 is opened on the side surface of the presser box 105.

  The resin sheet gripping part 103 clamps each edge of the resin sheet 117, positions the resin sheet 117 horizontally between the molding die 102 and the presser box 105, and a base material mounted on the molding die 102. Face 115. In FIG. 1, the resin sheet gripping portion 103 is schematically shown. Details of the resin sheet gripping portion 103 and the resin sheet 117 will be described later with reference to FIGS. 3 (a) and 3 (b).

  The heater 104 is transported in the horizontal direction by the heater transport device 118, and moves between a heating position that sandwiches the resin sheet 117 and a retracted position that is retracted from the heating position. The heater 104 positioned at the heating position heats and softens the resin sheet 117 clamped to the resin sheet gripping portion 103. FIG. 1 shows a state where the heater 104 is positioned at the heating position. When the heater 104 is positioned at the retracted position, the upper surface of the resin sheet 117 clamped by the resin sheet gripping portion 103 faces the presser box 105, and the lower surface of the resin sheet 117 is a base mounted on the molding die 102. It faces the material 115.

  The vacuum forming apparatus 101 includes a table transfer device 119 as a transfer unit. The table transport device 119 transports the table 112 in the vertical direction. As a result, the resin sheet 117 clamped by the resin sheet gripping portion 103 and the base material 115 attached to the molding die 102 are brought close to and away from each other.

  The vacuum forming apparatus 101 includes a press box transport device 120. The presser box transport device 120 transports the presser box 105 in the vertical direction. Here, the presser box 105 is formed with an opening edge portion 105a facing downward. Further, a sealing surface 102 a is formed on the molding die 102. The sealing surface 102a and the opening edge portion 105a are shaped to fit each other. When the press box 105 is lowered by driving the press box transport device 120, the opening edge 105a and the seal surface 102a come into contact with each other. The presser box transport device 120 further lowers the presser box 105 to press-contact the opening edge 105a and the seal surface 102a, and seals the space surrounded by the molding die 102 and the presser box 105.

  FIG. 2 is a side view of the molding die 102. Please refer to FIG. 1 and FIG. The support members 106 are provided at two locations (in FIG. 1, the front side and the back side of the drawing mold 102 in FIG. 1, and the left and right sides of the forming mold 102 in FIG. 2). Each of these two support members 106 includes an arm 121 and a contact body 122. The arm 121 is disposed adjacent to the molding die 102 and extends in the vertical direction. The arm 121 is connected to a cylinder device 107 disposed adjacent to the molding die 102, and is displaced in the vertical direction by driving the cylinder device 107. The contact body 122 is a rod-shaped member, and is attached to the upper end of the arm 121 and extends in the horizontal direction. As the arm 121 moves up and down, the contact body 122 is displaced between a position above the maximum height of the base material 115 and a position lower than this.

  FIG. 3A is a front view of the resin sheet gripping portion 103. FIG. 3B is a plan view of the resin sheet gripping portion 103. The resin sheet gripping part 103 includes a first clamp part 201, a second clamp part 202, and a third clamp part 203, and clamps the rectangular resin sheet 117.

  The 1st clamp part 201 clamps a part of edge part of each long side in the resin sheet 117. As shown in FIG. In more detail, the 1st clamp part 201 clamps two places which divide the long side of the resin sheet 117 into three equal parts, as shown to Fig.3 (a).

  The 2nd clamp part 202 is an edge part of each long side in resin sheet 117, Comprising: The location which is not clamped by the 1st clamp part 201 is clamped. More specifically, the second clamp portion 202 includes a central clamp portion 202a positioned at the two first clamp portions 201 on each long side of the resin sheet 117, a short side of the resin sheet 117, and the first clamp portion. 201, and an end clamp portion 202b positioned between the two.

  In addition, the 2nd clamp part 202 (the center clamp part 202a, the edge clamp part 202b) may clamp all the locations which are not clamped by the 1st clamp part 201 among the long sides of the resin sheet 117. And you may clamp the one part location which is not clamped by the 1st clamp part 201 among the long sides of the resin sheet 117. FIG.

  The 3rd clamp part 203 clamps the edge part of each short side in the resin sheet 117. FIG.

  Here, the 1st clamp part 201 and the center clamp part 202a are provided in the upper surface of the base member 204 on a flat plate. The end clamp part 202 b and the third clamp part 203 are provided on the upper surface of the frame member 205. The frame member 205 is disposed below the base member 204. The base member 204 is not connected to the frame member 205.

  FIG. 4A is a plan view showing a part of the resin sheet gripping portion 103. FIG. 4B is a front view showing a part of the resin sheet gripping portion 103. A rail 206 is provided on the upper surface of the base member 204. The rail 206 is located at the end of the base member 204 and extends parallel to the long side of the resin sheet 117. A slide body 207 is attached to the rail 206. The slide body 207 holds the first clamp part 201. For this reason, the first clamp part 201 is slidable along the rail 206. The slide body 207 is connected to one end of the link bar 208. A fixing point 209 that is fixed to the frame member 205 is provided at the other end of the link bar 208. The base member 204 includes a guide member 211 that extends downward. The guide member 211 enters a guide hole 212 (see FIG. 7B) provided in the frame member 205 and is slidable with respect to the guide hole 212. The guide member 211 restricts the movement of the base member 204 so that the base member 204 moves only in the vertical direction.

  The base member 204, the slide body 207, and the link bar 208 serve as the movable member 210. That is, when the base member 204 is displaced upward and away from the frame member 205, the link bar 208 rotates about the fixed point 209, and the slide body 207 slides along the rail 206 in a direction away from the central clamp portion 202a. Let As a result, as shown in FIG. 4B, the first clamp unit 201 moves so as to draw an arc centered on the fixed point 209, and deforms the resin sheet 117 being clamped.

  FIGS. 5A to 5C and FIGS. 6A to 6C are schematic views showing the flow of the vacuum forming method. Hereinafter, a procedure for forming the resin sheet 117 in close contact with the base material 115 using the vacuum forming apparatus 101 of the present embodiment will be described.

  First, the base material 115 is mounted on the convex surface 111 of the molding die 102. Then, each side of the resin sheet 117 is clamped to the resin sheet gripping portion 103, the resin sheet 117 is oriented horizontally, and the resin sheet 117 faces the molding die 102. In more detail, the edge part of the long side of the resin sheet 117 is clamped to the 1st clamp part 201 and the 2nd clamp part 202, and the side part of the short side of the resin sheet 117 is made to the 3rd clamp part 203. Clamp.

  Next, the heater conveyance device 118 is driven to position the heater 104 at the heating position (position where the resin sheet 117 is sandwiched), and the heater 104 is driven to heat the resin sheet 117 (FIG. 5A). Thereby, the resin sheet 117 is softened. At this time, each edge portion of the resin sheet 117 is held by each of the first clamp portion 201, the second clamp portion 202, and the third clamp portion 203, so that the softened resin sheet 117 is under its own weight. It is prevented that it hangs down and is deformed into an unintended shape.

  Next, the heater 104 is stopped, and the heater conveyance device 118 is driven to position the heater 104 at the retracted position (position retracted from the heating position). Subsequently, the table transport device 119 is driven to raise the table 112 and the molding die 102 (FIG. 5B). In this process, the contact body 122 of the support member 106 contacts the bottom surface of the base member 204. Here, immediately before the contact body 122 contacts the bottom surface of the base member 204, the resin sheet 117 is unclamped by the second clamp portion 202.

  FIG. 7A is a perspective view of the vacuum forming apparatus 101 before the resin sheet 117 is deformed and showing a state immediately before the contact body 122 contacts the base member 204. FIG. 7B is a perspective view of the vacuum forming apparatus 101 showing a state after the contact body 122 contacts the base member 204 and the resin sheet 117 is deformed. Here, with reference to FIG. 7A and FIG. 7B, how the resin sheet 117 is deformed as the molding die 102 moves upward will be described. As described above, immediately before the contact body 122 contacts the bottom surface of the base member 204, as shown in FIG. 7A, the first clamp part 201 and the third clamp part 203 clamp the resin sheet 117. However, the second clamp portion 202 does not clamp the resin sheet 117. In this state, when the table transport device 119 is driven and the table 112 is raised, the support member 106 is also raised, and the contact body 122 pushes the base member 204 upward (see FIGS. 4B and 7B). ). As a result, the link bar 208 rotates about the fixed point 209, and the slide body 207 slides along the rail 206. At this time, the first clamp unit 201 moves while drawing an arcuate trajectory TR as shown in FIG. Therefore, the change in the length of the end region of the resin sheet 117 from the first clamp part 201 to the third clamp part 203 (from the length L1 shown in FIG. 7A to the length shown in FIG. 7B). Change to the length L2) is a change in the case of evacuation without using the vacuum forming apparatus 101 of the present embodiment (from the length L3 shown in FIG. 8A to the length L4 shown in FIG. 8C). Is much smaller). Further, the link bar 208 rotates and the first clamp portion 201 slides, so that the shape of the resin sheet 117 approximates the base material 115 mounted on the molding die 102. Here, the movable member 210 (the base member 204, the slide body 207, and the link bar 208) and the support member 106 constitute a transmission portion 213.

  Returning to the description based on FIGS. 5A to 5C and FIGS. 6A to 6C. After sliding the first clamp part 201 to deform the resin sheet 117 (FIG. 5C), the cylinder device 107 is driven to move the support member 106 downward (FIG. 6A). Thereby, the deformed resin sheet 117 is in contact with the base material 115.

  Subsequently, the press box transport device 120 is driven to lower the press box 105 (FIG. 6A), and the resin sheet 117 is clamped and sealed with the press box 105 and the molding die 102 (FIG. b)). In this state, the suction device 113 is driven to perform suction from the hole 114, the resin sheet 117 is vacuum-formed, and the resin sheet 117 is adhered to the base material 115. At the same time, compressed air is formed by blowing compressed air from the vent 116 (FIG. 6B). By performing vacuum forming and pressure forming, the resin sheet 117 is brought into close contact with the base material 115 and becomes a molded product 214 (see FIG. 6C). After the molding is completed, the press box transport device 120 is driven to raise the press box 105, and the table transport device 119 is driven to lower the table 112 (FIG. 6C). Thereby, a molded product can be taken out from the molding die 102. After taking out the molded product, the cylinder device 107 (see FIG. 6A) is driven to position the support member 106 below the maximum height of the base material 115.

  As described above, according to the vacuum forming apparatus 101 of the present embodiment, the resin sheet 117 is deformed while the resin sheet 117 and the base material 115 approach and separate from each other, and the deformed resin sheet 117 contacts the base material 115. Thus, mold clamping and vacuum forming are performed, and therefore the resin sheet 117 can be adhered to the base material 115 without unevenness without causing wrinkles.

  In the present embodiment, the support member 106 that moves together with the molding die 102 pushes up the base member 204, the link bar 208 rotates, and the slide body 207 slides along the rail 206, thereby The clamp part 201 moves. That is, the resin sheet 117 is deformed by the change in the structure of each member. For this reason, the mechanism for deforming the resin sheet 117 does not fail due to the heat from the heater 104.

  Note that the mechanism for sliding and moving the first clamp unit 201 is not limited to the link mechanism using the link bar 208 as described above, but is also performed using an air cylinder, a motor, or the like that is driven along with the upward movement of the table 112. One clamp part 201 may be moved.

  Further, in the present embodiment, the table transport device 119 transports the table 112 in the vertical direction, and the resin sheet 117 and the base material 115 mounted on the molding die 102 come close to and away from each other. However, it suffices that at least one of the molding die 102 and the resin sheet 117 moves and the resin sheet 117 approaches and separates from the base material 115. For example, as another embodiment, the vacuum forming apparatus 101 includes a resin sheet conveyance device (not shown) that conveys the resin sheet gripping portion 103 in the vertical direction, and the resin sheet gripping portion 103 moves in the vertical direction. Thus, 117 clamped by the resin sheet gripping portion 103 and the base material 115 mounted on the molding die 102 may be brought close to and away from each other.

  In the present embodiment, the heater 104 moves and the resin sheet 117 clamped by the resin sheet gripping portion 103 is sandwiched between and the heater 104 heats the resin sheet 117. However, as another embodiment, the resin sheet gripping portion 103 is heated. May move so that the resin sheet 117 is positioned between the heaters 104.

DESCRIPTION OF SYMBOLS 101 Vacuum forming apparatus 102 Molding die 103 Resin sheet holding part 104 Heater (heating part)
106 Support member 113 Suction device (vacuum forming part)
115 Base material 117 Resin sheet 119 Table transport device (transport unit)
201 1st clamp part 202 2nd clamp part 203 3rd clamp part 209 Fixed point 210 Movable member 213 Transmission part

Claims (3)

A mold for mounting the substrate,
A first clamping part for clamping a part of one opposing edge of the rectangular resin sheet; a second clamping part for clamping at least a part of the other opposing edge of the resin sheet; and the resin A third clamp portion that clamps the other opposing edge of the sheet, and a resin sheet gripping portion that clamps each edge of the resin sheet and causes the resin sheet to face the substrate;
A heating unit for heating and softening the resin sheet clamped to the first clamp unit, the second clamp unit, and the third clamp unit;
A transport unit that moves at least one of the molding die and the resin sheet to move the resin sheet closer to and away from the base;
The movement of the molding die and the resin sheet by the conveying unit is transmitted to move away from the first clamp unit, and the second clamp unit is clamped by the first clamp unit and the third clamp unit. A transmission part for deforming the resin sheet in an unclamped state by the clamp part;
A vacuum forming section for clamping and vacuum forming the resin sheet in contact with the substrate by the transport section;
A vacuum forming apparatus comprising: The transmission unit is
A support member that moves with the molding die;
A movable member that has a fixing point that is fixed to the resin sheet gripping portion, is moved in contact with the support member, and moves the first clamp portion;
including,
The vacuum forming apparatus according to claim 1. A first clamping part for clamping a part of one opposing edge of the rectangular resin sheet; a second clamping part for clamping at least a part of the other opposing edge of the resin sheet; and the resin A third clamp portion that clamps the other opposing edge portion of the sheet, and clamps each edge portion of the resin sheet by a resin sheet gripping portion, and faces the resin sheet to the base material mounted on the molding die A process of
Heating and softening the resin sheet clamped to the first clamp part, the second clamp part, and the third clamp part;
Unclamping the second clamp part from the heat-softened resin sheet;
Moving at least one of the molding die and the resin sheet to move the resin sheet close to and away from the substrate;
Transmitting the movement of approaching and separating between the molding die and the resin sheet to the first clamp part to deform the heat-softened resin sheet;
A step of clamping and vacuum forming the resin sheet in contact with the substrate;
A vacuum forming method comprising:

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