Manufacturing method of air pad for detecting biological information

Abstract

To provide a method for manufacturing a highly airtight air pad in which a triple joint part of a tube and a pair of sheets is air tightly sealed.SOLUTION: A manufacturing method of an air pad for biological information detection includes the steps of: forming a weld by welding circumferential edges of sheets 2 and 3 by welder processing, with a cushion material 4 disposed between the sheets 2 and 3 and at that time. forming an unwelded part 16 in which the sheets are not welded together; inserting one end side of a tube 5 into the unwelded part 16, and clamping the unwelded part 16 and one end side of the tube 5 by jigs 31 and 32 of the welder to weld the sheets of the unwelded part 16 to the tube 5, where a relational expression 2L / (π×D) of the length L of the unwelded part 16 and an outer peripheral length π×D (D is an outer diameter of the tube) of the tube 5 is defined as 1.02-1.30.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a method for manufacturing an air pad for detecting biological information such as changes in the lying position of the human body (turning over, etc.), human heart rate, breathing, etc. [Background technology]

[0002] One biological information detection system for detecting biological information includes an air pad (air bag) filled with air, an air tube with one end inserted into the air bag, and a cushioning material (sponge) placed inside the air bag. Air is sealed inside the air bag, and the other end of the air tube is connected to a pressure detection sensor device. Multiple air bags are placed between the bed (bedding) and the human body, and changes in the human body's lying position can be detected from changes in air pressure inside the air bags. Heartbeat and breathing can also be detected based on air pressure detection signals (Patent Documents 1 and 2).

[0003] Fig. 6 is a perspective view showing an example of an air pad, Figs. 7 and 8 are cross-sectional views taken along lines VII-VII and VIII-VIII in Fig. 6, Fig. 9 is a cross-sectional view taken along line IX-IX in Fig. 8, and Fig. 10 is an enlarged view of part X in Fig. 9. Fig. 11 is a perspective view showing a conventional method for manufacturing an air pad.

[0004] 6 to 9, this air pad 1 has sheets 2 and 3 whose peripheral edges are welded or heat-sealed, a cushioning material 4 such as sponge interposed between the sheets 2 and 3, and a tube 5 whose one end is inserted into the air pad 1. The sheets 2 and 3 and the tube are made of a thermoplastic synthetic resin such as polyvinyl chloride resin. As shown in FIG. 11, this air pad 1 is manufactured by placing the cushioning material 4 such as sponge and one end of the thermoplastic synthetic resin tube 5 between two thermoplastic synthetic resin sheets 2 and 3, and then welding or heat-sealing the peripheral edges of the sheets 2 and 3. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent No. 5887676 [Patent Document 2] Patent No. 4423481 Summary of the Invention [Problem to be solved by the invention]

[0006] As described above, when manufacturing the air pad 1 by welding or heat sealing the sheets 2 and 3, the cushioning material 4 and one end of the tube 5 are interposed between the sheets 2 and 3, and the peripheral edges of the sheets 2 and 3 are sandwiched between them using a welder or heat sealer, followed by applying pressure and heat. Because the sheets 2 and 3 and the tube 5 are made of a thermoplastic synthetic resin, the sheets 2 and 3 are fused together by this pressure and heat application. The outer peripheral surface of the tube 5 is also fused to the sheets 2 and 3.

[0007] However, as shown in Figure 10, at the triple junction (side surface of the tube) where the outer surface of the tube 5 and the sheets 2 and 3 meet, tiny gaps can occur between the three, causing air leaks and reducing the accuracy of heart rate and respiration detection.

[0008] An object of the present invention is to provide a method for producing a highly airtight air pad in which the triple joint between the tube and the pair of sheets is airtightly sealed. [Means for solving the problem]

[0009] The gist of the present invention is as follows.

[0010] [1] A method for manufacturing an air pad for detecting biological information, comprising a pair of thermoplastic synthetic resin sheets whose peripheral edges are welded or heat-sealed, a cushioning material placed in the space surrounded by the sealed portion between the sheets, and a thermoplastic synthetic resin tube having one end inserted into the space and the other end extending outside the air pad, a method for manufacturing an air pad for detecting biological information, the method comprising the steps of: placing the cushion material between a pair of sheets, welding or heat-sealing the peripheral edges of the sheets together, forming an unfused portion along one side of the sheets where the sheets are not fused; inserting one end of the tube into the unfused portion; and clamping the unfused portion and the tube inserted in the unfused portion with a jig of a welder or heat-sealing device to fuse the sheet and the tube in the unfused portion, wherein the method for manufacturing an air pad for detecting biological information comprises the steps of: (a) placing the cushion material between the pair of sheets, welding or heat-sealing the peripheral edges of the sheets together, forming an unfused portion along one side of the sheets where the sheets are not fused; (b) inserting one end of the tube into the unfused portion; and (c) clamping the unfused portion and the tube inserted in the unfused portion with a jig of a welder or heat-sealing device to fuse the sheet and the tube in the unfused portion; and (d) satisfying the relationship 2L / (π×D), where L is the length of the unfused portion in the direction parallel to the one side of the unfused portion and π×D is the outer diameter of the tube, and

[0011] [2] The method for manufacturing an air pad for detecting biological information according to [1], wherein the jig has a semi-cylindrical recess on the surface facing the sheet for clamping the unfused portion into which the tube is inserted, and the radius r of the semi-cylindrical recess, the outer diameter D of the tube, and the thickness t of the sheet at the unfused portion satisfy the relationship that the value of 2r / (D+2t) is 0.70 to 0.98.

[0012] [3] The method for manufacturing an air pad for detecting biological information according to [1] or [2], wherein the space is rectangular, the fused portion has a pair of longitudinal fused portions along the long sides of the space and a pair of short fused portions along the short sides of the space, and the unfused portion is provided at one location along either the side of one of the short fused portions or the side of one of the longitudinal fused portions.

[0013] [4] A method for manufacturing an air pad for detecting biological information according to [1 to 3], wherein the thickness of the sheet before fusion is 50 to 1000 μm, the outer diameter of the tube is 2.0 to 7.0 mm, the wall thickness of the tube is 0.5 to 1.5 mm, the length a of the portion fused by the jig in the longitudinal direction of the tube is 3.0 to 20.0 mm, and the length b in the direction perpendicular to the tube is 10.0 to 60.0 mm.

[0014] [5] The method for manufacturing an air pad for detecting biological information according to any one of [1] to [4], wherein the thermoplastic synthetic resin is one of vinyl chloride resin, polyethylene resin, polypropylene resin, polyurethane resin, and fluororesin, and the materials of the fused surfaces of the tube and the sheet are the same.

[0015] [6] A method for manufacturing an air pad for detecting biological information according to any one of [1] to [5], in which a metal rod or a thermosetting resin rod with an outer diameter E is inserted into the inner side of a tube with an inner diameter d, and welding or heat sealing is performed, whereby the value of E / d is 0.8 to 1.0.

[0016] [7] A method for manufacturing an air pad for detecting biological information according to any one of [1] to [6], wherein a thickness adjusting sheet made of a thermoplastic resin or a thermosetting resin having a softening point 20°C or more higher than that of the thermoplastic resin and having a thickness of T is sandwiched between the surfaces facing the jig and the sheet, and welded or heat sealed, wherein the value of T / ((Dd) / 2) is 0.03 to 0.30. [Effects of the Invention]

[0017] According to the manufacturing method of the present invention for detecting biological information, the outer surface of the tube and the pair of sheets are fused together airtight at the triple junction, preventing air leakage from this triple junction, resulting in the manufacture of a highly airtight air pad. The results of the airtightness test are shown in Figure 13. [Brief explanation of the drawings]

[0018] [Figure 1] 10A to 10C are perspective views illustrating a method for manufacturing an air pad for detecting biological information according to an embodiment. [Figure 2] FIG. 2 is an enlarged cross-sectional view taken along line II-II in FIG. [Figure 3] FIG. 3 is a schematic enlarged view of part III in FIG. 2. [Figure 4] 4 is a view taken along the arrow IV in FIG. 1, showing a state in which a tube is inserted into a tube insertion portion between sheets. [Figure 5]FIG. 1 is an explanatory diagram showing a welder welding or heat sealing method. [Figure 6] FIG. 1 is a perspective view showing an example of an air pad. [Figure 7] FIG. 7 is a cross-sectional view taken along line VII-VII in FIG. 6. [Figure 8] FIG. 8 is a cross-sectional view taken along line VIII-VIII in FIG. 6. [Figure 9] FIG. 9 is a cross-sectional view taken along line IX-IX in FIG. 8. [Figure 10] FIG. 10 is an enlarged view of the X portion of FIG. 9. [Figure 11] FIG. 10 is a perspective view showing a conventional method for manufacturing an air pad. [Figure 12] FIG. 1 is an explanatory diagram showing a welder welding or heat sealing method. [Figure 13] These are the results of welder welding or heat seal tests. DETAILED DESCRIPTION OF THE INVENTION

[0019] A method for manufacturing an air pad for detecting biological information according to an embodiment will be described below with reference to FIGS.

[0020] The structure of the air pad 1 manufactured by the manufacturing method for an air pad for detecting biological information according to this embodiment is the same as that shown in Figures 6 to 9. That is, the air pad 1 has sheets 2 and 3 whose peripheral edges are welded or heat-sealed, a cushioning material 4 interposed between the sheets 2 and 3, and a tube 5 whose one end is inserted into the air pad 1. The sheets 2 and 3 and the tube 5 are made of a thermoplastic synthetic resin. The sheets 2 and 3 have the same thickness.

[0021] The cushioning material 4 is placed in a portion (space) surrounded by the fused portions 11 to 15 fused by welding or heat sealing.

[0022] To manufacture an air pad using the manufacturing method for an air pad for detecting biological information according to this embodiment, as shown in Fig. 1, a cushioning material 4 (not shown in Fig. 1) is interposed between two sheets 2 and 3, and the peripheral edges of the sheets 2 and 3 are welded or heat sealed. Fused portions 11 to 15 that fuse the sheets 2 and 3 together are formed by the welder or heat sealing.

[0023] The sheets 2 and 3 are rectangular, and the fused portions 11 and 12 extend along both long sides 21 and 22 of the rectangular sheets 2 and 3. The fused portions 11 and 12 extend linearly from one short side 23 of the sheets 2 and 3 to the other short side 24.

[0024] The fused portion 13 extends linearly from the long side portion 21 to the long side portion 22 along one of the short sides 23 of the sheets 2 and 3 .

[0025] Fused portions 14, 15 extend linearly along short side portion 24. Fused portion 14 extends from long side portion 21 to near the center of short side portion 24 in the side direction. Fused portion 15 extends from long side portion 22 to near the center of short side portion 24 in the side direction. The length in the extension direction of fused portions 14, 15 is shorter than half the side length of short side portion 24. Therefore, near the center of short side portion 24 in the side direction, an unfused portion 16 of length L (Figure 3) is formed between fused portions 14, 15.

[0026] In the present invention, this length L is set to 1.02 to 1.30 times the outer circumferential length of the tube 5. That is, when the diameter (outer diameter) of the tube 5 is D, 2L / (π×D) is set to 1.02 to 1.30. 2L / (π×D) is preferably set to 1.02 to 1.20, and particularly preferably to 1.02 to 1.10, where π is the ratio of the circumference of the tube to its circumference.

[0027] As shown in Figure 1, after the peripheral portions of sheets 2 and 3 are fused at fused portions 11 to 15, one end of tube 5 is inserted into unfused portion 16 as shown by arrow IV, and is inserted further back than fused portions 14 and 15 (the state shown in Figure 4. Note that Figure 4 is a view taken along arrow IV in Figure 1 after the tube has been inserted into unfused portion 16, and tube 5 is shown in cross section).

[0028] Thereafter, as shown in Fig. 5, the unfused portion 16 and its neighboring area are sandwiched from above and below by jigs 31 and 32 of a welder or heat sealing device, and pressure and heat are applied. Semi-cylindrical recesses 31a and 32a are provided on the opposing surfaces of jigs 31 and 32 (the lower surface of jig 31 and the upper surface of jig 32 in Fig. 5) to receive the tube 5 and the sheets 2 and 3 that overlap the tube 5, respectively.

[0029] In this embodiment, the radius r of the semi-cylindrical recesses 31a, 32a is set so that the relationship between the radius r of the semi-cylindrical recesses 31a, 32a, the thickness t of the sheets 2, 3 (thickness before fusion), and the diameter D of the tube 5 is as follows: That is, the radius r is set so that 2r / (D+2t) is preferably 0.70 to 0.98, and particularly preferably 0.80 to 0.98.

[0030] As described above, by setting the relationship 2L / π·D between the length L of the unfused portion 16 and the outer circumferential length π·D of the tube 5 to a small value of 1.03 to 1.30, i.e., by setting the inner diameter of the unfused portion 16 cylindrically so that it is only slightly larger than the outer diameter of the tube 5, the tube 5 and the sheets 2, 3 are fused together using jigs 31, 32, thereby preventing gaps from forming at the triple junction of the tube 5 and the sheets 2, 3. This improves the airtightness of the air pad 1.

[0031] Furthermore, by ensuring that the relationship between the radius r of the semi-cylindrical recesses 31a, 32a of the jigs 31, 32 of the welding or heat-sealing device, the thickness t of the sheets 2, 3, and the diameter (outer diameter) D of the tube 5 satisfies 2r / (D+2t) = 0.70 to 0.98, the inner circumferential surfaces of the recesses 31a, 32a firmly press the sheets 2, 3 against the outer circumferential surface of the tube 5 during welding or heat sealing. This prevents gaps from forming at the triple junctions between the tube 5 and the sheets 2, 3. This results in extremely high airtightness of the air pad 1. It is preferable that the corners where the inner circumferential surfaces of the semi-cylindrical recesses 31a, 32a of the jigs 31, 32 intersect with the opposing surfaces of the jigs 31, 32 be as sharp (not rounded) as possible within the tolerance of the manufacturing precision of the jigs.

[0032] The opposing surfaces of jigs 31, 32 may be in direct contact with sheets 2, 3, or thickness adjusting sheets 37, 38 may be provided on the opposing surfaces as shown in Fig. 12. Also, as shown in Fig. 12, a cylindrical rod (or cylindrical pipe) 36 may be inserted into tube 5 to prevent it from being crushed when pressed by jigs 31, 32. The ratio E / d of the rod or pipe outer diameter E to the tube inner diameter d is preferably 0.8 to 1.0.

[0033] The air pad manufactured in this way has good airtightness, and therefore can be used to accurately detect biological information such as changes in the lying position of the human body, heart rate, and breathing over a long period of time.

[0034] In the above embodiment, only one space surrounded by fused portions 11 to 15 is formed between sheets 2 and 3, but the present invention can also be applied to a case where a sheet whose length in the direction of sides 23 and 24 is two or three times or more that of Figure 1 is used, two or three or more such spaces are provided, and a tube 5 is inserted into each space.

[0035] In the above embodiment, the unfused portion 16 is located on the short side, but it may be located on the long side. Also, it may be located not in the center but at a position shifted from the center.

[0036] Although the present invention is not particularly limited, preferred conditions for the sheets 2 and 3, the tube 5, the cushioning material 4, and the heat sealing are as follows.

[0037] <Sheets 2 and 3> Materials: The fusion surface is a single layer of vinyl chloride resin, polyethylene resin, polypropylene resin, polyurethane resin, fluororesin (PTFE resin, etc.), or a single or multiple layer of resin is laminated on the non-fusion surface. Thickness: 50 to 1000 μm, especially 100 to 500 μm

[0038] <Distance between fused parts> Distance between fused parts 11 and 12: 30 to 150 mm, especially 40 to 100 mm Distance between fused portion 13 and fused portions 14, 15: 160 to 1000 mm, particularly 200 to 800 mm

[0039] <Tube 5> Material: vinyl chloride resin, polyethylene resin, polypropylene resin, polyurethane resin, fluororesin (PTFE resin, etc.), etc., and it is particularly preferable that the material be the same resin as sheets 2 and 3. Outer diameter: 2.0 to 7.0 mm, especially 3.0 to 6.0 mm Wall thickness: 0.5 to 1.5 mm, especially 0.7 to 1.2 mm

[0040] <Cushioning material 4> Materials: Polyurethane resin sponge, polyethylene resin sponge, styrene butadiene rubber sponge, natural rubber sponge, chloroprene rubber sponge, ethylene propylene rubber sponge, acrylonitrile butadiene rubber sponge, and sponges made of these mixed materials, etc. Thickness: 3-30mm, especially 5-15mm

[0041] <Welder welding> Fusion methods: High-frequency welder welding, which uses high-frequency dielectric heating to directly heat and weld the heated part, and ultrasonic welder welding, which transmits ultrasonic vibrations to the heated part to heat and weld it, etc. Fusion temperature: 80 to 150°C, especially 100 to 120°C Fusion time: 2 to 60 seconds, especially 3 to 30 seconds

[0042] <Heat seal> Fusion method: Heating method using a hot wire or hot plate heated by an external heat source by heat conduction Fusion temperature: 80 to 180°C, especially 100 to 140°C Fusion time: 5 to 120 seconds, especially 10 to 60 seconds

[0043] <Rod or pipe inserted inside the tube> Materials: SUS, aluminum, brass, and other metals, thermosetting resin Outer diameter: 1.0 to 4.0 mm, especially 1.6 to 3.6 mm

[0044] <Thickness adjustment sheet> Materials: Fluorine resin, epoxy resin, thermosetting polyimide resin, etc. Thickness: 35μm~350μm, especially 45μm~250μm

[0045] <Sizes of fused portions a and b by jigs 31 and 32 near tube 5> Length a of the fused portion in the longitudinal direction of the tube 5 (FIG. 8): 3.0 to 20.0 mm, particularly 4.0 to 15.0 mm Length b of the fused portion in the direction perpendicular to the tube 5 (FIG. 9): 10.0 to 60.0 mm, particularly 20.0 to 50.0 mm [Explanation of symbols]

[0046] 1 air pad 2,3 seats 4 Cushioning material 5 tubes 11~15 Fusion part 16 Unfused area 21,22 Long side 23,24 Short side 31, 32 Welder fusion or heat sealing equipment jig 31a,32a recess 36 Rod inserted into tube 37,38 Thickness adjustment sheet

Claims

1. A method for manufacturing an air pad for detecting biological information, comprising: a pair of thermoplastic synthetic resin sheets whose peripheral edges are welded or heat-sealed; a cushioning material disposed in a space surrounded by the heat-sealed fused portion between the sheets; and a thermoplastic synthetic resin tube having one end inserted into the space and the other end extending outside the air pad, a step of placing the cushion material between a pair of the sheets, fusing the peripheral edges of the sheets together by welding or heat sealing, and forming an unfused portion along one side of the sheets where the sheets are not fused; a step of inserting one end of the tube into the unfused portion; a step of clamping the unfused portion and the tube inserted into the unfused portion with a jig of a welder or a heat sealer to fuse the sheet and the tube in the unfused portion, The relationship between the length L of the unfused portion in a direction parallel to the one side and the outer circumferential length π×D of the tube (D is the outer diameter of the tube), 2L / (π×D), is set to 1.02 to 1.30; and the jig has a semi-cylindrical recess on the surface facing the sheet for clamping the unfused portion into which the tube has been inserted, and the radius r of the semi-cylindrical recess, the outer diameter D of the tube, and the thickness t of the sheet at the unfused portion satisfy the relationship that the value of 2r / (D+2t) is 0.70 to 0.

98.

2. 2. The method for manufacturing an air pad for detecting biological information according to claim 1, wherein the space is rectangular, the heat-sealed fusion portion has a pair of longitudinal fusion portions along the longer sides of the space and a pair of transverse fusion portions along the shorter sides of the space, and the unfused portion is provided in one location along one side of one of the transverse fusion portions or one of the longitudinal fusion portions.

3. the thickness of the sheet before fusion is 50 to 1000 μm, the outer diameter of the tube is 2.0 to 7.0 mm, and the wall thickness of the tube is 0.5 to 1.5 mm; 3. The method for manufacturing an air pad for detecting biological information according to claim 1 or 2, wherein the fused portion fused by the jig has a length a in the longitudinal direction of the tube of 3.0 to 20.0 mm, and the fused portion has a length b in a direction perpendicular to the longitudinal direction of the tube of 10.0 to 60.0 mm when viewed in plan.

4. 4. The method for manufacturing an air pad for detecting biological information according to any one of claims 1 to 3, wherein the thermoplastic synthetic resin is any one of vinyl chloride resin, polyethylene resin, polypropylene resin, polyurethane resin, and fluororesin, and the materials of the fused surfaces of the tube and the sheet are the same.

5. 5. A method for manufacturing an air pad for detecting biological information according to any one of claims 1 to 4, wherein a metal rod or a thermosetting resin rod having an outer diameter E is inserted into the inner surface of a tube having an inner diameter d, and welded or heat-sealed, and the value of E / d is 0.8 to 1.

0.

6. A method for manufacturing an air pad for detecting biological information according to any one of claims 1 to 5, wherein a thickness adjustment sheet made of a thermoplastic resin or a thermosetting resin having a softening point 20°C or more higher than that of the thermoplastic resin and having a thickness T is sandwiched between the surfaces facing the jig and the sheet, and welder welding or heat sealing is performed, wherein the value of T / ((D-d) / 2) is 0.03 to 0.30.

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