WINDING APPARATUS

Abstract

A winding apparatus configured to wind a sheet material is provided. The apparatus includes a belt configured to contact an outermost circumferential surface of a rolled material to rotate the rolled material, and a belt driving device configured to rotationally drive the belt. The apparatus is configured such that a radius of curvature of a portion of the belt configured to be in contact with the rolled material increases in conjunction with an increase in a diameter of the rolled material. The rolled material is the sheet material wound to form layers in its thickness direction. The sheet material is a flexible sheet-shaped member.

Claims

1. A winding apparatus configured to wind a sheet material that is a flexible sheet-shaped member, the winding apparatus comprising: a belt configured to contact an outermost circumferential surface of a rolled material to rotate the rolled material, the rolled material being the sheet material wound to form layers in its thickness direction; and a belt driving device configured to rotationally drive the belt, the winding apparatus being configured such that a radius of curvature of a portion of the belt configured to be in contact with the rolled material increases in conjunction with an increase in a diameter of the rolled material.

2. The winding apparatus according to claim 1, further comprising a first guide roller and a second guide roller configured to guide movement of the belt such that the portion of the belt configured to be in contact with the rolled material forms an annular portion in a substantially C-shape including an opening, wherein the first guide roller and the second guide roller are arranged on one side of the annular portion adjacent to the opening, and the first guide roller is arranged on one side of an imaginary line, and the second guide roller is arranged on an opposite side of the imaginary line, the imaginary line running in a direction of the opening.

3. The winding apparatus according to claim 2, further comprising a path modifying mechanism including a contact portion in contact with the belt, and being capable of modifying and adjusting a traveling path of the belt, wherein the contact portion of the path modifying mechanism is configured to be displaced toward the annular portion in accordance with an increase in an outer diameter of the annular portion.

4. The winding apparatus according to claim 3, further comprising a regulator configured to regulate a position of the annular portion such that the annular portion is positioned on one side of the imaginary line.

5. The winding apparatus according to claim 4, further comprising two or more feed rollers configured to contact the sheet material to feed the sheet material to the annular portion, wherein the two or more feed rollers are arranged in a width direction with the annular portion interposed therebetween, the width direction being parallel to a central axis of the rolled material.

6. The winding apparatus according to claim 5, wherein the two or more feed rollers include a first feed roller and a second feed roller, the first feed roller and the second feed roller are arranged with the imaginary line interposed therebetween, and the first feed roller and the second feed roller are configured such that a frictional force generated at a contact portion between the first feed roller and the sheet material is smaller than a frictional force generated at a contact portion between the second feed roller and the sheet material.

7. The winding apparatus according to claim 6, further comprising a tension generator configured to hold a first end and a second end of the sheet material in the width direction and pull the sheet material in the width direction to generate tension in the sheet material.

8. The winding apparatus according to claim 7, wherein the belt is a toothed belt including a projection and a groove on a side opposite a surface configured to contact the rolled material.

9. A winding apparatus configured to wind a sheet material that is a bag portion of an airbag, the winding apparatus comprising: a belt configured to contact an outermost circumferential surface of a rolled material to rotate the rolled material, the rolled material being the sheet material wound to form layers in its thickness direction; and a belt driving device configured to rotationally drive the belt, the winding apparatus being configured such that a radius of curvature of a portion of the belt configured to be in contact with the rolled material increases in conjunction with an increase in a diameter of the rolled material.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Some example embodiments of the present disclosure will be described hereinafter with reference to the accompanying drawings, in which:

[0025] FIG. 1 is a schematic view of a winding apparatus according to a first embodiment;

[0026] FIG. 2 is a schematic view illustrating a structure of the winding apparatus according to the first embodiment; and

[0027] FIG. 3 is a schematic view illustrating the structure of the winding apparatus according to the first embodiment.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

[0028] The present embodiments show some examples where a winding apparatus according to the present disclosure is applied to a winding apparatus configured to wind a bag portion of a curtain airbag installed in a vehicle, such as a car. The bag portion is an example of a flexible sheet-shaped member.

[0029] Hereinafter, the bag portion will be referred to as sheet material B1 (see FIG. 1). The sheet material B1 wound in a spiral manner to form layers in its thickness direction will be referred to as rolled material B2 (see FIG. 3).

[0030] Arrows for indicating directions, oblique lines, or the like in each drawing are used to facilitate understanding of mutual relations between the drawings, the shape of members or portions, or the like. Therefore, orientation of the winding apparatus is not limited to how the winding apparatus is oriented in each drawing.

[0031] The directions in each drawing are provided to show the orientation of the winding apparatus of the present embodiment when it is installed in a manufacturing site. A drawing with the oblique lines does not always represent a cross-sectional view. With respect to at least a member or a portion explained with a reference numeral, at least one of such a member or a portion is disposed unless it is described using a term such as only one of.

[0032] In other words, unless it is described using a term such as only one of, two or more of such a member or a portion may be disposed. The winding apparatus of the present disclosure includes at least one of elements, such as at least a member or a portion explained with a reference numeral, or a structural component shown in the drawings.

First Embodiment

[0033] <1. Configuration of Winding Apparatus>

[0034] As shown in FIG. 1, a winding apparatus 1 includes at least a belt 3, a belt driving device 5 (see FIG. 2), a first guide roller 7, a second guide roller 9, a feed roller 11 (see FIG. 2), a path modifying mechanism 13, a regulator 15, and a tension generator 17 (see FIG. 2).

Belt

[0035] As shown in FIG. 3, the belt 3 is a continuous track configured to contact the outermost circumferential surface of the rolled material B2 to rotate the rolled material B2. The belt 3 according to the present embodiment is a toothed belt with projections and grooves on one side opposite the surface configured to contact the rolled material B2.

[0036] As shown in FIG. 1, the belt 3 runs over the first guide roller 7, the second guide roller 9 and an intermediate roller 13A of the path modifying mechanism 13. The first guide roller 7, the second guide roller 9, and the intermediate roller 13A are an example of a path guide member configured to guide the belt 3 along a traveling path.

[0037] As shown in FIG. 2, the belt 3 of the present embodiment has a dimension Wb in a width direction that is smaller than a dimension Ws of the sheet material B1 in the width direction. The term width direction refers to a direction parallel to the central axis of the rolled material B2, or of the respective shafts 7A and 9A of the first and second guide rollers 7 and 9.

Guide Roller

[0038] As shown in FIG. 3, the first guide roller 7 and the second guide roller 9 are configured to guide the belt 3 such that an annular portion 3A is formed by the belt 3. The annular portion 3A refers to a portion of the belt 3 configured to be in contact with the rolled material B2, and is an annular portion with a partial opening, that is a substantially C-shaped portion. In other words, an opening 3B is formed in the annular portion 3A.

[0039] As shown in FIG. 1, the first guide roller 7 and the second guide roller 9 are arranged on one side of the annular portion 3A adjacent to the opening 3B, that is, on the one side of the annular portion 3A opposite from the intermediate roller 13A.

[0040] The first guide roller 7 is arranged on a one side of an imaginary line Lo (on the upper side of the imaginary line Lo in FIG. 1). The second guide roller 9 is arranged on the opposite side of the imaginary line Lo (on the lower side of the imaginary line Lo in FIG. 1).

[0041] The imaginary line Lo is a line running in a direction that aligns with a direction of the opening 3B (a line representing an imaginary plane). The direction of the opening 3B is parallel to an imaginary line tangent to the outer circumference of the first guide roller 7 and an imaginary line tangent to the outer circumference of the second guide roller 9.

[0042] Of imaginary lines tangent to the outer circumference of the second guide roller 9, the imaginary line Lo according to the present embodiment is an imaginary line parallel to an imaginary line tangent to the outer circumference of the first guide roller 7. Specifically, the imaginary line Lo is a horizontal line tangent to the outer circumference of the second guide roller 9. More specifically, the imaginary line Lo is an imaginary line tangent to the outer circumference of the second guide roller 9 and a straight line between the first guide roller 7 and the second guide roller 9 orthogonal to a line segment connecting the center of the first guide roller 7 and the center of the second guide roller 9.

[0043] The horizontal line tangent to the outer circumference of the second guide roller 9 overlaps the solid line representing the belt 3. For this reason, the imaginary line Lo is drawn in FIG. 1 at a position where the imaginary line Lo does not overlap the solid line representing the belt 3 for clear distinction between the imaginary line Lo and the belt 3.

[0044] In the present embodiment, a shaft 9A of the second guide roller 9 (see FIG. 2) is supported by a frame 19. The shaft 9A is immovable with respect to the frame 19. A shaft 7A of the first guide roller 7 (see FIG. 2) is supported by a pivot arm 21.

[0045] The pivot arm 21 is an arm-shaped frame pivotably coupled to the frame 19. The pivot center of the pivot arm 21 is set at a position shifted from the shafts 9A and 7A toward the intermediate roller 13A.

[0046] As shown in FIG. 1, the first guide roller 7 and the second guide roller 9 are spaced apart from each other so that the opening 3B is formed. The sheet material B1 comes into contact with a portion of the belt 3 adjacent to the second guide roller 9, that is the belt 3 on the lower side of the opening 3b.

Path Modifying Mechanism

[0047] The path modifying mechanism 13 is capable of modifying and adjusting the traveling path of the belt 3. The path modifying mechanism 13 includes at least the intermediate roller 13A and a roller support 13B. The intermediate roller 13A is an example of a contact portion in contact with the belt 3.

[0048] The intermediate roller 13A contacts the belt 3 at a position shifted toward the annular portion 3A (to the left in FIG. 1) from the first guide roller 7 and the second guide roller 9 to rotate the belt 3, thereby regulating the traveling path of the belt 3.

[0049] The intermediate roller 13A includes a shaft (not shown) displaceable in directions parallel to the imaginary line Lo. The shaft is supported by the frame 19 in a displaceable manner. The roller support 13B together with the frame 19 supports the intermediate roller 13A in a displaceable manner.

[0050] The roller support 13B according to the present embodiment includes a spring, for example. The frame 19 is provided with an elongated hole (not shown) in which the shaft of the intermediate roller 13A is inserted. The major axis of the elongated hole is parallel to the imaginary line Lo.

[0051] As the outer diameter of the annular portion 3A increases, the intermediate roller 13A is displaced to be closer to the annular portion 3A. Thus, as winding of the sheet material B1 progresses and the diameter of the rolled material B2 increases, a portion of the belt 3 configured to be in contact with the rolled material B2 increases in size, in other words, the radius of curvature of the annular portion 3A increases, in conjunction with the increase in the diameter of the rolled material B2.

Regulator

[0052] The regulator 15 performs a function to regulate the position of the annular portion 3A such that the annular portion 3A is positioned on one side (in FIG. 1, the upper side) of the imaginary line Lo. The regulator 15 according to the present embodiment includes a roller configured to rotate in contact with the outer circumferential surface of the annular portion 3A. The roller is displaceable in accordance with a change in the outer diameter of the annular portion 3A.

Feed Roller

[0053] The feed roller 11 is a mechanism configured to contact the sheet material B1 and feed the sheet material B1 to the annular portion 3A. As shown in FIG. 2, the feed roller 11 according to the present embodiment includes at least four rollers 11A to 11D.

[0054] Specifically, the feed roller 11 includes a first feed roller and a second feed roller. The first feed roller includes two rollers 11A and 11B. The rollers 11A and 11B are arranged on a first side (on the upper side in FIG. 1) of the imaginary line Lo.

[0055] The second feed roller includes two rollers 11C and 11D. The rollers 11C and 11D are arranged on a second side (on the lower side in FIG. 1) of the imaginary line Lo.

[0056] Of the two rollers 11A and 11B of the first feed roller, a first roller is arranged on a first side of the annular portion 3A, that is the belt 3, in the width direction, and a second roller is arranged on a second side of the belt 3 in the width direction.

[0057] Similarly, of the two rollers 11C and 11D of the second feed roller, a first roller is arranged on the first side of the belt 3, that is the annular portion 3A, in the width direction, and a second roller is arranged on the second side of the belt 3 in the width direction.

[0058] Furthermore, the first feed roller and the second feed roller are configured such that a frictional force generated at a contact portion between the first feed roller (specifically, the rollers 11A and 11B) and the sheet material B1 is smaller than a frictional force generated at a contact portion between the second feed roller (specifically, the rollers 11C and 11D) and the sheet material B1.

[0059] Specifically, the first feed roller and the second feed roller each include a material different from each other. The roughness of the outer circumferential surfaces of the first feed roller is smaller than that of the outer circumferential surfaces of the second feed roller.

[0060] In the present embodiment, the hardness of the outer circumferential surfaces of the second feed roller is smaller than that of the outer circumferential surfaces of first feed roller. Thus, the outer circumferential surface of the second feed roller is configured to contact the sheet material B1 while elastically deforming so as to closely contact the sheet material B1.

[0061] The first feed roller is pressed toward the second feed roller via the pivot arm 21. In the present embodiment, the first feed roller is pressed toward the second feed roller using a pressing device (not shown) that utilizes gravity acting on, for example, a weight.

Belt Driving Device

[0062] The belt driving device 5 is a driving source configured to rotationally drive the belt 3. As shown in FIG. 2, the belt driving device 5 according to the present embodiment is configured to rotationally drive the second guide roller 9 to thereby rotationally drive the belt 3.

[0063] The belt driving device 5 is also configured to drive at least one of the first feed roller (specifically, the rollers 11A and 11B), or the second feed roller (specifically, the rollers 11C and 11D) (in the present embodiment, the second feed roller is driven) simultaneously with the second guide roller 9.

Tension Generator

[0064] As shown in FIG. 2, the tension generator 17 is a mechanism configured to pull the sheet material B1 in the width direction (in the left-right direction of the drawing in FIG. 2) and generate tension in the sheet material B1. Specifically, the tension generator 17 at least includes two holding components 17A and two pulling components 17B.

[0065] The two holding components 17A are sheet clamps configured to respectively pinch and hold the opposing ends of the sheet material B1 in the width direction. Each pulling component 17B is configured to exert a force on the corresponding holding component 17A so that the two holding components 17A are spaced apart from each other.

[0066] Each holding component 17A is rotatable in accordance with or in conjunction with rotation of the feed roller 11 or the rolled material B2. This enables the tension generator 17 to generate tension in the sheet material B1 in a direction parallel to the width direction irrespective of rotation of the rolled material B2.

[0067] <3. Feature of Winding Apparatus of Present Embodiment>

[0068] In the winding apparatus 1 according to the present embodiment, the belt 3 is configured to contact the outermost circumferential surface of the rolled material B2 to rotate the rolled material B2, thereby winding the sheet material B1 to form the rolled material B2. This makes it possible in the winding apparatus to reduce the diameter of a winding shaft or to eliminate the winding shaft.

[0069] In the present embodiment, when the belt 3 is driven, the belt 3 forming the annular portion 3A moves in a circular and rotating manner. At this time, the leading end of the sheet material B1 which has been fed to the annular portion 3A from the opening 3B contacts the inner wall of the annular portion 3A, and thus moves in a circular manner together with the belt 3 forming the annular portion 3A.

[0070] On this account, the leading end side of the sheet material B1 curls along the inner wall of the annular portion 3A (see FIG. 1), and an initial state of the rolled material B2, that is one roll of the sheet material B1, is formed. At this time, the belt 3 contacts the outermost circumferential surface of the rolled material B2 in the initial state and rotates, and the sheet material B1 is thus wound in the spiral manner (see FIG. 3).

[0071] Consequently, as winding of the sheet material B1 continuously progresses, the outer diameter of the rolled material B2 gradually increases. At this time, the belt 3 contacts the outer circumferential surface of the rolled material B2 such that the belt 3 substantially entirely covers the outer circumferential surface of the rolled material B2, since the annular portion 3A is substantially C-shaped.

[0072] This can enable the winding apparatus 1 to reliably rotate the rolled material B2, thus enabling reliable winding of the sheet material B1. In other words, if slipping occurs at a contact portion between the annular portion 3A (the belt 3) and the rolled material B2, the sheet material B1 cannot be wound efficiently.

[0073] To address this, the annular portion 3A is substantially C-shaped, the belt 3 thus contacts the substantially entire area of the outer circumferential surface of the rolled material B2. This hinders occurrence of slipping at the contact portion between the belt 3 and the rolled material B2 and thus can enable efficient winding of the sheet material B1.

[0074] The winding apparatus 1 is provided with the path modifying mechanism 13 capable of modifying and adjusting the traveling path of the belt 3, and the intermediate roller 13A of the path modifying mechanism 13 is configured to be displaced to be closer to the annular portion 3A as the outer diameter of the annular portion 3A increases.

[0075] This enables the inner diameter dimension of the annular portion 3A to be increased as winding of the sheet material B1 progresses. In other words, as winding of the sheet material B1 progresses, the outer diameter of the rolled material B2 increases accordingly.

[0076] Thus, to continuously wind the sheet material B1, it is necessary to increase the inner diameter dimension of the annular portion 3A in accordance with an increase in the outer diameter of the rolled material B2.

[0077] To address this, the intermediate roller 13A is displaceable to be closer to the annular portion 3A in accordance with an increase in the outer diameter of the annular portion 3A, that is the outer diameter of the rolled material B2. Thus, it is possible to increase the inner diameter dimension of the annular portion 3A in accordance with the progress of winding of the sheet material B1.

[0078] The winding apparatus 1 is provided with the regulator 15 configured to regulate the position of the annular portion 3A such that the annular portion 3A is positioned on one side of the imaginary line Lo. This makes it possible to reliably wind the sheet material B1 to form a roll.

[0079] If the center of the annular portion 3A is positioned on the imaginary line Lo, the leading end of the sheet material B1 orthogonally hits the inner wall of the annular portion 3A at the beginning of winding of the sheet material B1.

[0080] In this state, the leading end side of the sheet material B1 is in an unstable state where it is uncertain in which direction the leading end side will be bent. This is because the state is similar to that where links of a linkage are each positioned at a change point (which is also referred to as dead point).

[0081] At this time, if the leading end side of the sheet material B1 is bent in a direction opposite the direction originally intended, it may be no longer possible to properly wind the sheet material B1. However, the annular portion 3A is configured to be positioned on one side of the imaginary line Lo in the present embodiment.

[0082] Thus, the leading end side of the sheet material B1 is consistently bent toward the aforementioned side. This ensures that the sheet material B1 bents along the inner wall of the annular portion 3A. Further, this makes it possible to reliably wind the sheet material B1 to form a roll.

[0083] The winding apparatus 1 allows insertion of the leading end of the sheet material B1 into the annular portion 3A in both cases: a case where the leading end of the sheet material B1 is inserted into the annular portion 3A with the leading end side of the sheet material B1 folded into two; and a case where the leading end is inserted without the leading end side folded into two.

[0084] The feed rollers 11 according to the winding apparatus 1 are arranged on one side and the opposite side of the annular portion 3A in the width direction. This makes it possible to feed the sheet material B1 to the annular portion 3A without the sheet material B1 being angled with respect to the direction of feeding.

[0085] The winding apparatus 1 is configured such that the frictional force generated at the contact portion between the first feed roller (specifically, the rollers 11A and 11B) and the sheet material B1 is smaller than the frictional force generated at the contact portion between the second feed roller (specifically, the rollers 11C and 11D) and the sheet material B1.

[0086] This inhibits winding of the sheet material B1 from being obstructed even when the outer circumferential surface of the rolled material B2 is in contact with the first feed roller, and can enable reliable feeding of the sheet material B1.

[0087] Since the annular portion 3A is close to the first feed roller, winding of the sheet material B1 and feeding of the sheet material B1 may be obstructed as the outer diameter of the rolled material B2 increases and the rolled material B2 contacts the first feed roller.

[0088] However, because of the configuration of the winding apparatus 1 in which the frictional force generated at the contact portion between the first feed roller and the sheet material is smaller than the frictional force generated at the contact portion between the second feed roller and the sheet material B1, it is possible to inhibit occurrence of the obstruction.

[0089] The winding apparatus 1 includes the tension generator 17 configured to pull the sheet material B1 in the width direction and generate tension in the sheet material B1. This can enable reliable winding of the sheet material B1 with the winding apparatus 1, including winding of the sheet material B1 with a large dimension in the width direction.

[0090] The belt 3 of the winding apparatus 1 is a toothed belt with projections and grooves on one side opposite the surface configured to contact the rolled material B2. This can inhibit the belt 3 from slipping against the belt driving device 5.

Other Embodiments

[0091] In the above-described embodiment, a portion of the belt 3 configured to be in contact with the rolled material B2 constitutes the substantially C-shaped annular portion 3A. However, the present disclosure is not limited to this. According to the present disclosure, the portion of the belt 3 configured to be in contact with the rolled material B2 may form an arc shape with a circumferential angle of approximately 5 to 30 degrees, for example.

[0092] The belt 3 in the above-described embodiment is a toothed belt. However, the present disclosure is not limited to this. According to the present disclosure, the belt 3 may include a flat belt without projections and grooves, for example.

[0093] The path modifying mechanism 13 in the above-described embodiment is provided with the intermediate roller 13A and the roller support 13B including a spring. However, the present disclosure is not limited to this. According to the present disclosure, the roller support 13B may include an electrically controlled actuator, and include a contact portion composed of a member, such as a shoe, configured to make sliding contact with the belt 3.

[0094] In the above-described embodiment, the path modifying mechanism 13 is provided. However, the present disclosure is not limited to this. According to the present disclosure, the path modifying mechanism 13 may be eliminated in a case where, for example, the belt 3 includes rubber and is elastically stretchable.

[0095] In the above-described embodiment, the regulator 15 includes a roller. However, the present disclosure is not limited to this. According to the present disclosure, the regulator 15 may include a member, such as a shoe, configured to make sliding contact with the belt 3, for example.

[0096] In the above-described embodiment, the regulator 15 is provided. However, the present disclosure is not limited to this. According to the present disclosure, the regulator 15 may be eliminated in a case, for example, where the belt 3 rotates in a direction opposite the direction shown in FIG. 1, since gravity acts on the rolled material B2 and the annular portion 3A such that the annular portion 3A is positioned on the lower side of the imaginary line Lo in such a case.

[0097] In the above-described embodiment, the feed roller 11 is arranged on one side and the opposite side of the annular portion 3A. However, the present disclosure is not limited to this. According to the present disclosure, the feed roller 11 may be arranged only on one side of the annular portion 3A, for example.

[0098] The configuration in the above-described embodiment is such that the frictional force generated at the contact portion between the first feed roller (specifically, the rollers 11A and 11B) and the sheet material B1 is smaller than the frictional force generated at the contact portion between the second feed roller (specifically, the rollers 11C and 11D) and the sheet material B1. However, the present disclosure is not limited to this.

[0099] According to the present disclosure, the frictional force generated with the first feed roller and the frictional force generated with the second feed roller may be the same, provided that the annular portion 3A is arranged at a position sufficiently spaced apart from the feed roller 11, for example.

[0100] The pressing device in the above-described embodiment has a configuration in which gravity is utilized. However, the present disclosure is not limited to this. According to the present disclosure, the pressing device may be configured to press the first feed roller toward the second feed roller with a spring, for example.

[0101] In the above-described embodiment, the bag portion of the airbag is described as an example of the sheet material B1. However, application of the present disclosure disclosed herein is not limited thereto. In other words, the present disclosure may be applied to other types of the sheet material B1, for example.

[0102] Furthermore, the present disclosure is only required to coincide with the gist of the disclosure described in the aforementioned embodiments and thus should not be limited to the aforementioned embodiments. Therefore, the present disclosure may include a configuration obtained by combining at least two of the aforementioned embodiments, or a configuration obtained by eliminating part of the elements in the drawings or the elements described with reference numerals in the aforementioned embodiments.