JP6764558B2 - How to manufacture the structure - Google Patents

Description

The present disclosure relates to a method for manufacturing a structure in which at least a part of the outer peripheral surface of a pipe is covered with resin.

Conventionally, a structure in which at least a part of the outer peripheral surface of a pipe is covered with resin has been known as an interior material or a functional member of a commercial facility, a building material, or a packaging material. For example, as shown in Patent Document 1 below, it is a hollow double wall structure composed of a front wall, a back wall, and a peripheral wall forming a hollow portion between the front wall and the back wall, and is hollow. It is known that a pipe is arranged in the part.

Japanese Patent No. 3680193

By the way, in a structure in which at least a part of the outer peripheral surface of the pipe is covered with resin, the pipe is mainly used for the purpose of increasing the rigidity or strength of the structure, or by connecting to another member via the pipe. It is used for the purpose of making the structure rotatable around the pipe axis. In particular, in the latter case, highly accurate positioning of the pipe in the rotational direction may be required so that the pipe can be appropriately connected to other members to be connected.
However, in the conventional manufacturing method of a structure in which at least a part of the outer peripheral surface of the pipe is covered with resin, the pipe is axially rotated due to the shrinkage of the resin in the process of cooling the hot molten resin in contact with the pipe. A force is generated to rotate the pipe, which may cause the position of the pipe in the rotational direction around the axis to deviate from the design position when the structure is completed.

Therefore, it is an object of the present disclosure to improve the accuracy of the position in the rotational direction around the axis of the pipe when manufacturing a structure in which at least a part of the outer peripheral surface of the pipe is covered with resin. ..

One aspect of the present disclosure is a method for manufacturing a structure in which at least a part of the outer peripheral surface of the pipe is covered with resin, and the molding surface of the mold is brought into contact with at least a part of the outer peripheral surface of the pipe. as rotation about the axis of the pipe is restricted, to hold the pipe to the holding member, the holding member is movable in the axial direction of the pipe, the forming surface and the pipe a molten resin sheet The resin is molded by pressing against the outer peripheral surface of the pipe, and the holding member is configured to cover at least a part of the outer peripheral surface of the pipe which is not covered with the resin in the structure. The holding member is provided in the axial direction of the pipe between a first position that does not cover at least a part of the outer peripheral surface of the pipe and a second position that covers at least a part of the outer peripheral surface of the pipe. It is characterized by being movable.

In the manufacturing method, the holding member may be configured to cover at least a part of the outer peripheral surface of the pipe which is not covered with the resin in the structure.

In the manufacturing method, the holding member is located between a first position that does not cover at least a part of the outer peripheral surface of the pipe and a second position that covers at least a part of the outer peripheral surface of the pipe. It may be movable in the axial direction of.

In the manufacturing method, the cross section of the portion of the outer peripheral surface of the pipe covered with the resin may have a non-circular shape.

In the manufacturing method, in the laminated body, the pipe is made of a ferromagnetic material, and in the mold, a magnet is arranged in the vicinity of the molding surface in contact with at least a part of the outer peripheral surface of the pipe. You may.

In the manufacturing method, the mold includes a pipe support portion that supports the pipe, and the pipe support portion has a contact surface that contacts one end of the pipe and the contact surface from the other end of the pipe to the contact surface. An urging means for urging the other end of the pipe in the direction toward the pipe may be provided.

According to the method for manufacturing a structure according to the present disclosure, when manufacturing a structure in which at least a part of the outer peripheral surface of the pipe is covered with resin, the accuracy of the position in the rotational direction around the axis of the pipe is good. Can be.

It is a perspective view of the retractable multipurpose sheet which concerns on embodiment. It is a top view of the resin board which concerns on embodiment. It is sectional drawing which shows the AA cross section of FIG. It is a figure explaining the assembly method of the resin board which concerns on embodiment. It is a figure which shows a part of the manufacturing apparatus used for manufacturing the resin board which concerns on embodiment. It is a figure explaining the operation of a holding member. It is an enlarged perspective view which shows a part of a part of a split die before and after the pipe is inserted into a split die. It is a figure explaining the operation of the ball plunger before and after the pipe is inserted into a split mold. It is a figure which looked at the pipe included in the resin board which concerns on embodiment from the arrow view G, I of FIG. It is a figure which looked at the holding member from the arrow view G, H of FIG. It is a figure explaining the engaging operation of a pipe and a holding member. It is a figure explaining the manufacturing method of the resin board which concerns on embodiment. It is a figure explaining the manufacturing method of the resin board which concerns on embodiment. It is a figure explaining the manufacturing method of the resin board which concerns on embodiment. It is a figure explaining the manufacturing method of the resin board which concerns on embodiment. It is a figure explaining the manufacturing method of the resin board which concerns on embodiment. It is a figure explaining the manufacturing method of the resin board which concerns on embodiment. It is a figure explaining the engaging operation of a pipe and a holding member in the modified example of embodiment. It is a figure explaining the engaging operation of a pipe and a holding member in the modified example of embodiment.

(1) Resin board according to the embodiment (an example of a structure)
Hereinafter, the structure of the resin board according to the embodiment of the present invention will be described. The resin board according to the embodiment is a member constituting the seating surface of the retractable multipurpose seat.
FIG. 1 is a perspective view of the retractable multipurpose sheet 100 according to the embodiment. The retractable multipurpose sheet 100 includes a resin board 1 and a storage portion 5.
The resin board 1 includes a resin laminate 2 that is mainly used as a seating surface for multiple purposes, and a pipe 3 that is attached to the resin laminate 2. A part of the pipe 3 is covered with the resin laminate 2. The exposed portion of the pipe 3 that is not covered by the resin laminate 2 is attached to the storage portion 5, whereby the resin laminate 2 of the resin board 1 is configured to be rotatable around the axis of the pipe 3. .. Although the connection structure between the pipe 3 of the resin board 1 and the storage portion 5 is not shown, high accuracy is required for the position of the pipe 3 in the rotational direction around the axis in order to properly connect with the storage portion 5.

FIG. 1 shows a case where the retractable multipurpose sheet 100 is in a used state, but when it is not in a used state, the resin laminate 2 of the resin board 1 rotates around the axis of the pipe 3 and is stored. It is configured to be housed in the recess 5a of the portion 5.

Next, the structure of the resin board 1 according to the embodiment will be described in more detail with reference to FIGS. 2 to 4. FIG. 2 is a plan view of the resin board 1 according to the embodiment. FIG. 3 is a cross-sectional view showing a cross section taken along the line AA of FIG. FIG. 4 is a diagram illustrating a method of assembling the resin board 1 according to the embodiment.

As shown in FIG. 2, the resin board 1 is a substantially rectangular plate-shaped member as a whole, and the pipes 3 are arranged in parallel with the short side in a state of being separated from the end corresponding to the short side thereof. The central portion 3C of the pipe 3 is built in the resin laminate 2 (that is, covered with resin), and the right end portion 3R and the left end portion 3L of the pipe 3 are exposed for connection with the storage portion 5. ing.
As shown in FIG. 3, the resin laminate 2 includes a first resin sheet 21 formed on the front side, a second resin sheet 22 mainly formed on the back side, and a first resin sheet 21. It has a laminated structure composed of a core material 23 interposed between the second resin sheets 22. The first resin sheet 21 is a sheet that serves as a seating surface for the retractable multipurpose sheet 100.

Both the first resin sheet 21 and the second resin sheet 22 are non-foaming resins, and the resin material thereof is not limited, but is a thermoplastic resin such as polyolefin, and the polyolefin is low density polyethylene or straight chain. Examples thereof include low-density polyethylene, high-density polyethylene, polypropylene, ethylene-propylene copolymers and mixtures thereof.

The core material 23 is molded using, for example, a thermoplastic resin. The resin material is not limited, and includes, for example, any of polyolefins such as polypropylene and polyethylene, acrylic derivatives such as polyamide, polystyrene and polyvinyl chloride, or a mixture of two or more kinds. The core material 23 occupies a large proportion of the volume of the resin board 1, and is preferably a foamed resin foamed using a foaming agent in order to reduce the weight. The foaming ratio of the foamed resin used as the core material 23 is, for example, in the range of 10 to 60 times, and is typically 30 times. The foaming ratio is a value obtained by dividing the density of the mixed resin before foaming by the apparent density of the foamed resin after foaming.

The pipe 3 is made of a ferromagnetic metal, and may be subjected to surface treatment such as plating in order to improve the slipperiness of the surface if necessary. The cross-sectional shape of the pipe 3 is not particularly limited, but the cross-sectional shape of the central portion 3C built in the resin laminate 2 is such that the pipe 3 rotates around the central axis after the completion of the resin board 1 and the storage portion 5 is used. The non-circular shape is preferable so that the connection is not difficult (that is, in order to maintain the position of the pipe 3 around the central axis with high accuracy). In the example shown in FIG. 3, the cross-sectional shape of the central portion 3C of the pipe 3 is an elliptical shape as a non-circular shape, but the shape is not limited to this shape, and may be, for example, a polygonal shape.
The cross-sectional shapes of the right end portion 3R and the left end portion 3L of the pipe 3 are appropriately designed according to the shape of the storage portion 5 to be connected.
At least one end of the pipe 3 is provided with a notch for restricting the rotation of the pipe 3 around the axis when molding the resin laminate 2, and this point will be described later.

In the method for manufacturing the resin board 1 of the present embodiment, the resin laminate 2 is molded by vacuum forming, which will be described later, and the resin board 1 is assembled based on the molded resin laminate 2.
Steps S1 to S3 of FIG. 4 show each step in order when assembling the resin board 1 based on the molded resin laminate 2. Step S1 of FIG. 4 shows a state immediately after molding of the resin laminate 2 of the resin board 1. Immediately after molding of the resin laminate 2, the second resin sheet 22 is formed longer than the first resin sheet 21 in the direction in which the long side of the resin board 1 extends, and the second resin sheet 22 is formed longer. The central portion 3C of the pipe 3 is incorporated in the resin laminate 2 by folding back the end portion of the resin sheet 22.

More specifically, as shown in step S1 of FIG. 4, the second resin sheet 22 immediately after molding, which will be described later, has a thin portion serving as a hinge H in the direction in which the long side of the resin board 1 extends, and the thin wall portion. Includes a sheet end portion 22a outside the portion. The end of the sheet end 22a is the sheet end 22e of the second resin sheet 22.

Next, as shown in step S2 of FIG. 4, the sheet end portion 22a of the second resin sheet 22 is folded back toward the first resin sheet 21 with the hinge H as the center from the state of step S1. As a result, the sheet end 22e of the second resin sheet 22 and the stepped portion 21s of the first resin sheet 21 come into contact with each other, and the front surface of the resin board 1 is in the vicinity of the stepped portion 21s of the first resin sheet 21. Becomes a smooth surface. After the sheet end 22a of the second resin sheet 22 is folded back, the hole 221 is opened using a hole opening device (not shown) such as a drill.
Finally, as shown in step S3 of FIG. 4, rivets R (two places as a whole of the resin board 1 as shown in FIG. 1) are inserted through the holes 221. As a result, the sheet end portion 22a of the second resin sheet 22 is fixed to the first resin sheet 21, and the resin board 1 is completed.

(2) Method for Manufacturing Resin Board Next, the method for manufacturing the resin board 1 of the present embodiment will be described.

(2-1) Preparation Step Before Molding First, in manufacturing the resin board 1, the preparation step before molding will be described with reference to FIGS. 5 to 11. FIG. 5 is a diagram showing a part of a manufacturing apparatus used for manufacturing the resin board 1 according to the embodiment. FIG. 6 is a diagram illustrating the operation of the holding members 60R and 60L. FIG. 7 is an enlarged perspective view showing a part of the split mold 51 before and after the pipe 3 is inserted into the split mold 51. FIG. 8 is a diagram illustrating the operation of the ball plunger (described later) before and after the pipe 3 is inserted into the split mold 51. FIG. 9 is a view of the pipe 3 included in the resin board 1 according to the embodiment as viewed from the arrows G and H of FIG. FIG. 10 is a view of one holding member 60R as viewed from the arrows G and I of FIG. FIG. 11 is a diagram illustrating an engagement operation between the pipe 3 and one of the holding members 60R.

In the method for manufacturing the resin board 1 according to the present embodiment, the holding member is held before molding so that the pipe 3 is not displaced or rotated during molding of the resin laminate 2 using the split dies 51 and 52. The pipe 3 is fixed to the molding surface 51a of the split mold 51 using at least one of 60R and 60L. In the example described below, the holding member 60R regulates the rotation of the pipe 3 around the central axis.
FIG. 5 is a view seen from a direction orthogonal to the molding surface 51a of one of the split dies 51, and shows a state in which the pipe 3 is held by the holding members 60R and 60L. When the pipe 3 is held by the holding members 60R and 60L, the holding members 60R and 60L are configured to cover the right end 3R and the left end 3L of the pipe 3, respectively.

One end of each of the holding members 60R and 60L is connected to the rods 70R and 70L. The actuators 80R and 80L are configured to drive the rods 70R and 70L so that the rods 70R and 70L move back and forth along the central axis of the pipe 3, thereby driving the holding members 60R and 60L.

Hereinafter, a method of holding the pipe 3 by the holding members 60R and 60L will be described with reference to FIG. In FIG. 6, in step S10, the holding members 60R and 60L are located at positions on the outer peripheral surface of the pipe 3 that do not cover the right end 3R and the left end 3L (an example of the first position), and in step S11, the holding members 60R and 60L are located. 60L is at a position (an example of the second position) of the outer peripheral surface of the pipe 3 that covers the right end portion 3R and the left end portion 3L.
The split mold 51 is provided with a pipe support portion 40 for supporting the pipe 3.

In step S10 of FIG. 6, first, the pipe 3 is set in the pipe support portion 40 of the split mold 51 by an operator or a manipulator (not shown). As will be described in detail later, the pipe support portion 40 of the split mold 51 is provided with a recess having a shape that matches the pipe 3, so that the position of the pipe 3 in the rotation direction is appropriate in the recess. The operator or manipulator sets the pipe 3. As shown in FIG. 6, a magnet M is embedded in the pipe support portion 40 of the split mold 51 at a position where it comes into contact with the surfaces of the right end portion 3R, the center portion 3C, and the left end portion 3L of the pipe 3. Since the ferromagnetic pipe 3 is fixed (temporarily held) to the split mold 51 by the magnetic force, the pipe 3 does not fall in the step S10.
In the example shown in FIG. 6, the magnet M is embedded corresponding to substantially the entire axial direction of the pipe 3, but the present invention is not limited to this example. As long as the pipe 3 can be temporarily held by the magnet M, the magnet M may be embedded corresponding to a part of the region of the pipe 3 (for example, only the region corresponding to the central portion 3C).

As shown in FIG. 6, it is preferable that one or a plurality of lead-in holes DP are formed in the pipe support portion 40 facing the outer peripheral surface of the central portion 3C of the pipe 3. The lead-in hole DP can effectively draw the molten resin into a narrowed region between the molding surface 51a of the split die 51 and the central portion 3C of the pipe 3 when shaping the molten resin in the molding step described later. It is provided so that it can be done. The central portion 3C of the pipe 3 and the portion of the molding surface 51a corresponding to the central portion 3C are in contact with each other, but due to the dimensional error of the shapes of the two and / or the difference in the surface roughness of the two, they are between the two. Is formed with a slight gap, and air is sucked through the gap during molding to effectively draw the molten resin into the narrowed region between the molding surface 51a of the split mold 51 and the central portion 3C of the pipe 3. Can be done.

Next, in step S11, the actuators 80R and 80L are controlled to move the holding members 60R and 60L in directions close to each other. As a result, the holding member 60R moves to a position that covers the right end portion 3R of the pipe 3, and the holding member 60L moves to a position that covers the left end portion 3L of the pipe 3. At this time, the pipe 3 is fixed inside the holding member 60R so that the pipe 3 does not rotate during the molding of the resin laminate 2.

Here, in step S10 of FIG. 6, a method of setting the pipe 3 on the pipe support portion 40 of the split mold 51 will be described with reference to FIG. 7. FIG. 7 shows an enlarged part of the pipe support portion 40 in which the right end portion 3R of the pipe 3 is set.
The pipe support portion 40 is a portion that supports the pipe 3 and is provided in the split mold 51. As shown in FIG. 7, the pipe support portion 40 includes an end surface 44R (an example of an abutting surface) that abuts on the end surface of the right end portion 3R, which is one end of the pipe 3, and a left end portion 3L, which is the other end of the right end portion 3R. An urging means for urging the end surface of the left end portion 3L in the direction from the end surface to the end surface 44R may be provided. As an example of the urging means, the ball plunger 48 will be mentioned in the following description.

As shown in the upper view of FIG. 7 (a view showing the state before the pipe is inserted), the pipe support portion 40 of the split mold 51 mounts a part of the outer peripheral surface of the pipe 3 on the entire axial direction of the pipe 3. It is configured so that it can be placed on the mounting surface 45. A pipe insertion region 41 defined by side walls 42 and 43 for restricting the pipe 3 from falling off due to rotation is formed at the end of the pipe support portion 40 in which the right end portion 3R of the pipe 3 is arranged. The end surface 44R of the pipe insertion area 41 for positioning the end surface of the right end portion 3R is formed in the pipe insertion region 41 by abutting the end surface of the right end portion 3R of the pipe 3. The end face 44R of the pipe insertion region 41 is formed of a substantially semicircular region, and a magnet M is embedded therein. As shown in the lower view of FIG. 7 (a view showing the state after the pipe is inserted), the end face of the right end 3R of the pipe 3 is held by the magnetic force on the end face 44R of the pipe insertion region 41 by the magnet M, and the pipe The misalignment of 3 in the axial direction is suppressed.

In the resin board 1 according to the present embodiment, in order to more accurately position the end surface of the right end portion 3R of the pipe 3 in the axial direction, the pipe support portion 40 is provided with an urging means for pressing the pipe 3 against the end surface 44R. It may be provided. As described above, as an example of such urging means, an example in which a ball plunger is used will be described with reference to FIG.

FIG. 8 schematically shows the pipe support portion 40 of the split mold 51 when viewed from the arrow G of FIG. In the pipe insertion region 41 of the pipe support portion 40, a left end surface 44L is formed so as to face the right end surface 44R. As shown in FIG. 8, the split mold 51 has a built-in ball plunger 48 on the left side of the end surface 44L of the pipe insertion region 41, and the tip of the ball of the ball plunger 48 is directed from the end surface 44L to the end surface 44R. It is protruding. Here, assuming that the total length of the pipe 3 is L1 and the distance between the ball tip of the ball plunger 48 and the end surface 44R of the pipe insertion region 41 before the pipe 3 is inserted into the pipe insertion region 41 is L2, L2 < It has an L1 relationship.

Since the relationship of L2 <L1 is established before the pipe 3 (total length L1) is inserted into the pipe insertion area 41, the ball of the ball plunger 48 is moved to the end face 44L side by inserting the pipe 3 into the pipe insertion area 41. Displace. In the state after the pipe 3 is inserted, the end surface of the left end portion 3L of the pipe 3 does not come into contact with the end surface 44L of the pipe insertion region 41, and a gap is secured between the two. In the state where the pipe 3 is inserted into the pipe insertion area 41, the pipe 3 is urged by the spring of the ball plunger 48, whereby the pipe 3 is pressed against the right end surface 44R of the pipe insertion area 41. Since the state in which the pipe 3 is pressed against the end surface 44R of the pipe insertion region 41 is maintained until the molding of the resin described later is completed, the position of the end surface of the right end portion 3R of the pipe 3 on the completed resin board 1 is accurate. Is in a high state.
Further, when the right end portion 3R of the pipe 3 is required to have high mounting accuracy with the connecting portion (not shown) of the storage portion 5 to which the pipe 3 is connected, the accuracy of the axial length of the pipe 3 is required. Since the end face of the right end 3R of the pipe 3 is surely pressed against the end face 44L even when the height is not high, the accuracy of axial positioning of the end face of the right end 3R of the pipe 3 on the completed resin board 1 is improved. Can be high.

The urging means for pressing the pipe 3 against the end surface 44R is not limited to the ball plunger described above. For example, the member that comes into contact with the end surface of the left end portion 3L of the pipe 3 is not limited to the ball. The member may be any member as long as it can transmit a force to the right with respect to the end surface of the left end portion 3L of the pipe 3, and may be, for example, a plate-shaped member. Further, a leaf spring may be used instead of the coil spring or together with the coil spring.
In order to improve the accuracy of positioning the end surface of the left end portion 3L of the pipe 3 in the axial direction, an urging means such as a ball plunger 48 is built in the right side of the pipe support portion 40, contrary to the above-mentioned case. 3 may be pressed against the left end surface 44L of the pipe insertion region 41.

Next, a method of fixing the pipe 3 by the holding member 60R will be further described with reference to FIGS. 9 to 11. In the example described below, the case where the rotation regulation of the pipe 3 is performed on the holding member 60R side will be described, but the same rotation regulation structure is applied to the holding member 60L side instead of the holding member 60R side or together with the holding member 60R side. It will be understood by those skilled in the art that it is possible to do so.
FIG. 9 shows a part of the shape of the end of the right end portion 3R of the pipe 3. As shown in FIG. 9, two notches 3a are provided at the end of the right end portion 3R of the pipe 3.
FIG. 10 shows the shape of the holding member 60R. As shown in FIG. 10, the holding member 60R includes a wall portion 601 having a U-shaped cross section and an engaging pin 602 provided near the end face on the side close to the holding member 60L. The engagement pin 602 is fixed to the inner wall of the wall portion 601 by welding or press fitting. The diameter of the engagement pin 602 is slightly smaller than the width of the notch 3a of the pipe 3.
The cross section of the wall portion 601 is not limited to the U-shape illustrated in FIG. 10, and may be circular or elliptical.

In FIG. 11, a step S10 in which the holding member 60R does not cover the right end 3R of the outer peripheral surface of the pipe 3 and a step S11 in which the holding member 60R covers the right end 3R of the outer peripheral surface of the pipe 3 Shows the relationship between the holding member 60R and the pipe 3. The stages S10 and S11 in FIG. 11 correspond to the stages S10 and S11 in FIG. 6, respectively.
As shown in FIG. 11, when shifting from the step S10 to the step S11, the wall portion 601 of the holding member 60R moves so as to cover the right end portion 3R of the pipe 3 fixed to the molding surface 51a of the split mold 51. To do. Then, at the position where the engaging pin 602 fixed to the inner wall of the wall portion 601 of the holding member 60R is inserted into the notch 3a of the right end portion 3R of the pipe 3, the movement of the holding member 60R is controlled to stop. Will be done. As a result, the displacement of the pipe 3 with respect to the split mold 51 is regulated, and the rotation of the pipe 3 around the central axis is regulated.

As shown in step S11 of FIG. 11, when the holding member 60R is stopped, it is preferable that the engaging pin 602 of the holding member 60R does not come into contact with the stopper of the notch 3a of the pipe 3. When the engaging pin 602 comes into contact with the stopper of the notch 3a of the pipe 3, the engaging pin 602 exerts a force to push the pipe 3 to the left, which causes the ball of the ball plunger 48 to be displaced to the left, thereby causing the pipe. This is because the position of the end surface of the right end portion 3R of 3 may shift to the left side.

(2-2) Molding process A molding process is performed after the preparation process. 12 to 17 are diagrams for explaining the molding process of the resin board 1 according to the embodiment, respectively. In each figure, the cross section of the divided dies 51 and 52 at the center is shown, and the aspect ratio of the resin board 1 to be molded does not necessarily match those shown in FIGS. 1 to 3.
As shown in FIG. 12, in the molding process of the resin board 1, a pair of split dies 51 and 52 corresponding to the shape of the resin laminate 2 of the resin board 1 are prepared. That is, the molding surface 51a of the split mold 51 has a shape corresponding to the first resin sheet 21, and the molding surface 52a of the split mold 52 has a shape corresponding to the second resin sheet 22. By the preparation step described above, the pipe 3 is fixed to the molding surface 51a of the split die 51.
The split mold 51 is provided with sliding portions 511, 512, and the split mold 52 is provided with sliding portions 521 and 522. The sliding portion 511 and the sliding portion 521 can slide in the directions facing each other, and the sliding portion 512 and the sliding portion 522 can slide in the directions facing each other.

First, as shown in FIG. 12, in step S20, molten resin sheets (parisons) P and P are extruded from an extruder (not shown) and hung between the split dies 51 and 52.

Next, as shown in FIG. 13, in step S21, the sliding portions 511 and 521 are moved (sliding) in directions close to each other, and the sliding portions 521 and 522 are moved (sliding) in directions close to each other. By allowing the tip of each sliding portion to come into contact with the molten resin sheet P. As a result, a closed space is formed between the molding surface 51a of the split mold 51 and the molten resin sheet P, and a closed space is formed between the molding surface 52a of the split mold 52 and the molten resin sheet P.
Although not shown, each of the divided dies 51 and 52 has a built-in vacuum chamber, and a communication passage for vacuum suction is provided between the vacuum chamber and the molding surfaces 51a and 52a. Then, the air in the closed space is sucked from the communication passage by the vacuum chamber. By this suction, as shown in step S22 of FIG. 14, the pair of molten resin sheets P and P are pressed against the molding surfaces 51a and 52a, respectively, and are molded (formed) into a shape along the molding surfaces 51a and 52a, respectively. To. At this time, as shown in FIG. 6, a lead-in hole DP is formed in the split mold 51 facing the outer peripheral surface of the central portion 3C of the pipe 3, and the air in the closed space is sucked from the lead-in hole DP. Therefore, the molten resin can be effectively drawn into the narrowed region between the molding surface 51a of the split mold 51 and the outer peripheral surface of the central portion 3C of the pipe 3.

Next, as shown in FIG. 15, in step S23, each sliding portion is returned to the initial position (the same position as in FIG. 12), and the melt formed on the forming surfaces 51a and 52a of the dividing dies 51 and 52. The core material 23 held by the manipulator 90 is accurately positioned between the resin sheets P and P. Then, one surface of the core material 23 is pressed against the molten resin sheet P formed on the molding surface 52a. As a result, the core material 23 is welded and fixed to the molten resin sheet P formed on the molding surface 52a.

Next, as shown in FIG. 16, in step S24, the split dies 51 and 52 are molded to sandwich the molten resin sheets P and P and the core material 23. By this mold clamping, the other surface of the core material 23 is pressed against the molten resin sheet P formed on the molding surface 51a of the split mold 51 and welded.
A pinch-off portion (not shown) is provided on the outer periphery of the split dies 51 and 52 so as to surround the molding surfaces 51a and 52a of the split dies 51 and 52, and the molten resin sheets P and P are formed by molding. At the pinch-off portion, the peripheral edges of the pair of molten resin sheets P and P are welded to form a parting line (not shown).

Next, the split dies 51 and 52 are opened. Then, the actuators 80R and 80L are controlled to move the holding members 60R and 60L in directions away from each other (in short, steps S11 to S10 in FIG. 6). As a result, the fixing of the pipe 3 by the holding member 60R is released, and the holding members 60R and 60L cover the right end 3R and the left end 3L of the pipe 3, respectively (an example of the second position) and do not cover the pipe 3 (first position). The holding members 60R and 60L move to (an example of one position).

After moving the holding members 60R and 60L, the molded product is taken out as shown in step S25 of FIG. Then, by cutting the burr formed along the parting line with a cutter, the resin laminate 2 into which the pipe 3 is inserted can be obtained. Finally, as described with reference to FIG. 4, the resin laminate 2 into which the pipe 3 is inserted is opened with a hole 221 after bending the sheet end portion 22a of the second resin sheet 22 at the hinge H. The resin board 1 is completed by fixing the sheet end portion 22a to the first resin sheet 21 with a rivet R through the hole 221.

As described above, according to the method for manufacturing the resin board 1 (an example of the structure) according to the present embodiment, at least a part of the outer peripheral surface of the pipe 3 is brought into contact with the molding surface 51a of the split mold 51, and the pipe is formed. The molten resin is molded by holding the pipe 3 on the holding member 60R and pressing the molten resin sheet P against the molding surface 51a and the outer peripheral surface of the pipe 3 so that the rotation around the axis of 3 is restricted. At this time, in the process of cooling and solidifying the molten resin in contact with the pipe 3, a force for rotating the pipe 3 around the central axis may act due to heat shrinkage of the resin, but the pipe 3 rotates around the central axis. It is fixed to the molding surface 51a so as to be regulated. Therefore, in the method for manufacturing the resin board 1 of the present embodiment, it is possible to prevent the pipe 3 from rotating around its central axis due to heat shrinkage of the resin.

Further, according to the method for manufacturing the resin board 1 according to the present embodiment, the right end portion 3R and the left end portion 3L, which are exposed portions of the pipe 3, are covered with the holding member 60R and the holding member 60L, respectively, during the molding of the resin. ing. Therefore, since the resin does not adhere to the outer peripheral surfaces of the right end portion 3R and the left end portion 3L of the pipe 3 in the resin molding process, it is not necessary to remove unnecessary resin from the outer peripheral surface of the pipe 3 after molding. ..

Although the embodiment of the present invention has been described in detail above, the method for producing the structure of the present invention is not limited to the above-described embodiment, and various improvements and changes have been made without departing from the gist of the present invention. Of course, it is also good.

In the above embodiment, the method of fixing the pipe by the holding member is not limited to the method illustrated in FIG. 11, and other methods may be adopted. 18 and 19 are diagrams for explaining the engagement operation of the pipe and the holding member in the modified example of the embodiment, respectively.

In the example shown in FIG. 18, the pipe 3A according to the modified example includes a pipe portion 31 and two engaging pins 32 provided in the vicinity of the end surface of the pipe portion 31. Two notches 60Aa are provided at the end of the holding member 60A according to the modified example. That is, the configuration is opposite to that of the method shown in FIG. 11 in that an engaging pin is provided on the pipe side and a notch is provided on the holding member side.
As shown in FIG. 18, when shifting from the step S10 to the step S11, the holding member 60A is moved so as to cover the end portion of the pipe 3A fixed to the molding surface 51a of the split mold 51. Then, the notch 60Aa provided in the holding member 60A is controlled so that the movement of the holding member 60A is stopped at the position where the engaging pin 32 at the end of the pipe 3A is received. As a result, the displacement of the pipe 3A with respect to the split mold 51 is regulated, and the rotation of the pipe 3A around the central axis is regulated.

In the example shown in FIG. 19, only the holding member is different from that shown in FIG. The end portion of the holding member 60B according to the modified example forms a flat plate-shaped portion (flat plate portion).
As shown in FIG. 19, when shifting from the step S10 to the step S11, the holding member 60B is moved so as to cover the end portion of the pipe 3 fixed to the molding surface 51a of the split die 51. Then, at the position where the flat plate portion of the holding member 60B is inserted into the notch 3a of the right end portion 3R of the pipe 3, the movement of the holding member 60B is controlled to stop. As a result, the displacement of the pipe 3 with respect to the split mold 51 is regulated, and the rotation of the pipe 3 around the central axis is regulated.
As shown in FIG. 19, the holding member does not necessarily have to cover the end portion of the pipe 3, but it is necessary because the resin adheres to the outer peripheral surface of the end portion of the pipe 3 in the subsequent resin molding step. Accordingly, after molding the resin, the resin adhering to the end of the pipe 3 is removed.

In the pipe fixing methods exemplified in FIGS. 11, 18, and 19, respectively, a method of providing two notches and engaging pins at one end of the pipe to fix the pipe is shown, but one cutting method is shown. It may be fixed by notches and engaging pins.

In the method for manufacturing the resin board 1 according to the above-described embodiment, the case where the resin laminate 2 of the resin board 1 is formed by vacuum forming has been described, but blow molding may be applied instead of vacuum forming. Vacuum forming and blow molding may be used together.
Further, in the method for manufacturing the resin board 1 according to the above-described embodiment, the case where the sheet-shaped molten resin sheets P and P are hung between the split dies 51 and 52 has been described, but the annular molten resin (annular parison) has been described. ) May be hung between the split dies 51 and 52 to perform resin molding.

100 ... Retractable multipurpose sheet, 1 ... Resin board (an example of a structure), 2 ... Resin laminate, 21 ... First resin sheet, 22 ... Second resin sheet, 22a ... Sheet edge, 221 ... Hole, 23 ... Core material, 3,3A ... Pipe, 3a ... Notch, 31 ... Pipe part, 32 ... Engagement pin, 3C ... Central part, 3R ... Right end part, 3L ... Left end part, 5 ... Storage part, 5a ... Recession , R ... rivet, H ... hinge, 40 ... pipe support, 41 ... pipe insertion area, 42, 43 ... side wall, 44R, 44L ... end face, 45 ... mounting surface, 48 ... ball plunger, 51, 52 ... split metal Mold, 51a, 52a ... Molded surface, 511,521 ... Sliding part, 60R, 60L, 60A, 60B ... Holding member, 60Aa ... Notch, 601 ... Wall part, 602 ... Engagement pin, 70R, 70L ... Rod, 80R, 80L ... actuator, 90 ... manipulator, M ... magnet, DP ... lead-in hole, P ... molten resin sheet

Claims (4)

A method for manufacturing a structure in which at least a part of the outer peripheral surface of a pipe is covered with resin.
The holding member holds the pipe so that at least a part of the outer peripheral surface of the pipe is brought into contact with the molding surface of the mold and the rotation of the pipe around the axis is restricted.
The holding member is movable in the axial direction of the pipe and
The resin is molded by pressing the molten resin sheet against the molding surface and the outer peripheral surface of the pipe .
The holding member is configured to cover at least a part of the outer peripheral surface of the pipe which is not covered with resin in the structure.
The holding member moves in the axial direction of the pipe between a first position that does not cover at least a part of the outer peripheral surface of the pipe and a second position that covers at least a part of the outer peripheral surface of the pipe. Characterized by being possible,
Method of manufacturing the structure. The cross section of the portion of the outer peripheral surface of the pipe covered with the resin is characterized by having a non-circular shape.
The method for manufacturing a structure according to claim 1 . The pipe is made of ferromagnet
The mold is characterized in that a magnet is arranged in the vicinity of the molding surface in contact with at least a part of the outer peripheral surface of the pipe.
The method for producing a structure according to claim 1 or 2 . A method for manufacturing a structure in which at least a part of the outer peripheral surface of a pipe is covered with resin.
The holding member holds the pipe so that at least a part of the outer peripheral surface of the pipe is brought into contact with the molding surface of the mold and the rotation of the pipe around the axis is restricted.
The mold includes a pipe support that supports the pipe.
The pipe support portion includes a contact surface that comes into contact with one end of the pipe, and an urging means that urges the other end of the pipe in a direction from the other end of the pipe toward the contact surface.
The resin is molded by pressing the molten resin sheet against the molding surface and the outer peripheral surface of the pipe.
Method of manufacturing the structure.

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