The present invention relates to a shaft support structure in two members, which are molded articles made from synthetic resin, or the like, for supporting both sides of a rotating shaft provided on one member in a pair of shaft-bearing openings provided on the other member.
There is conventionally known, as an example of this kind of shaft supporting structure, an optical device having a connection plate having a shaft-bearing part and a rack having a rotating shaft, wherein two shaft-bearing openings are provided on the shaft-bearing part, at least one being constituted as a cutout hole, and a D-cut part to be inserted into the cutout hole is formed on an outer perimeter surface of the rotating shaft, whereby elimination of rattling in a thrust direction and in a radial direction is devised (see Patent Document 1).
Also, there is known, for example, one relating to a shaft support structure in a loop clutch made of synthetic resin, wherein a loop clutch body and a belt installation body are integrally molded simultaneously in one step, in a state in which a rotating shaft provided on the loop clutch body is inserted with play into a shaft-bearing opening provided on the belt installation body (see Patent Document 2).
Patent Document 1: Japanese Unexamined Patent Publication No. H5-187431
Patent Document 2: Japanese Examined Patent Publication No. H6-74802
However, in the prior art described in the abovementioned Patent Document 1, the external dimensions of the rotating shaft are set to be roughly equal to the internal dimensions of the shaft-bearing opening, and there is a problem that the two members (rack and connection plate) must be molded separately because a space in the mold during molding cannot be assured in a state in which the two members have been assembled (that is, a state in which the rotating shaft has been inserted in the shaft-bearing opening).
Also, in the prior art described in the abovementioned Patent Document 2, because the shaft-bearing structure is such that the rotating shaft is inserted with play in the shaft-bearing opening, a space in the mold can be assured, but there is a problem that rotational movement with good precision cannot be expected and the uses become limited.
The present invention is proposed in consideration of the problems of such conventional technology, and an object thereof is to provide a shaft support structure in a case when a rotating shaft provided on one of two members constituted by molded articles is supported in a pair of shaft-bearing openings provided on the other, wherein the precision of rotational movement can be assured to be good and simultaneous molding of the two members in the same mold is made possible.
According to a first aspect of the present invention, which was created in order to solve the abovementioned problems, a shaft support structure, relating to a rotating member (11) and shaft-bearing members (12, 13), which are molded articles, for supporting rotating shafts (24, 25) provided on the rotating member in a pair of shaft-bearing openings (32, 36) provided on the shaft-bearing member, wherein said rotating shaft has a held part (37) held in at least one shaft-bearing opening (36), said held part has a cross-section of a noncircular shape and a plurality of maximum outer perimeter edge parts (51, 52) arranged at a maximal distance from a center (C) of rotation and spaced apart from each other in a circumferential direction. Said at least one shaft-bearing opening has a noncircular shape and has a plurality of corresponding inner perimeter edge parts (53, 54) arranged in correspondence with said maximum outer perimeter edge parts. A distance from said center of rotation to said maximum outer perimeter edge parts and a distance from said center of rotation to said corresponding inner perimeter edge parts are the same in a state in which said rotating shaft is held in said at least one shaft-bearing opening, and at least one part between said maximum outer perimeter edge parts and said corresponding inner perimeter edge parts is in mutual sliding contact only in a case when said rotating shaft is within a prescribed range of rotation.
Also, according to a second aspect of the present invention, said maximum outer perimeter edge parts and said corresponding inner perimeter edge parts have arc forms having the same curvature as each other.
Also, according to a third aspect of the present invention, each of said maximum outer perimeter edge parts respectively is arranged in symmetric positions based on said center of rotation in a state in which each is spaced apart from each other in the circumferential direction; and said corresponding inner perimeter edge parts are arranged in plural in correspondence with the positions of said maximum outer perimeter edge parts.
Also, according to a fourth aspect of the present invention, said rotating shaft has an expanded-diameter part (29) formed adjacent to said held part in an axial direction of the shaft and in a position toward the side of the other end than the held part, and the expanded-diameter part projects outwardly from said held part than said maximum outer perimeter edge part in a diameter direction.
Also, according to a fifth aspect of the present invention, said rotating member has a coupling part (26) engageable with said shaft-bearing member; and said shaft-bearing member has a corresponding coupling part (38) for restricting rotational movement of the rotating member within said prescribed range of rotation by coupling with said coupling part.
Also, according to a sixth aspect of the present invention, said rotating member and said shaft member can be pre-assembled e in a state in which said rotating shaft is held in said at least one shaft-bearing opening.
According to the abovementioned first aspect of the present invention, in a structure relating to two members (a rotating member and a shaft-bearing member) which are molded articles, for supporting both sides of a rotating shaft provided on one (the rotating member) in a pair of shaft-bearing openings provided on the other (the shaft-bearing member): at least one part between the maximum outer perimeter edge parts and the corresponding inner perimeter edge parts is in mutual sliding contact only in the case when the rotating shaft is within a prescribed range of rotation; meanwhile, a gap arises between the outer perimeter edge of the rotating shaft and the inner perimeter edge of the shaft-bearing opening in the case when the rotating shaft is outside the prescribed range of rotation. Accordingly, there are excellent effects that, while the rotational movement of the rotating member can be assured to be good by rotating the rotating shaft within the prescribed range of rotation, the two members can be molded simultaneously in the same mold by performing molding in a state in which the rotating shaft is outside the prescribed range of rotation.
Also, according to the abovementioned second aspect of the present invention, the structures of the rotating shaft and the shaft-bearing opening are simplified, and the rotating shaft can be rotated with higher precision within the prescribed range of rotation.
Also, according to the abovementioned third aspect of the present invention, the structures of the rotating shaft and the shaft-bearing openings are simplified, and the range of rotation in which the precision of rotational movement of the rotating shaft can be assured to be good can be assured more widely.
Also, according to the abovementioned fourth aspect of the present invention, movement (rattling) of the rotating shaft in the axial direction can be restricted by contacting the expanded-diameter part to the end face of the shaft-bearing opening.
Also, according to the abovementioned fifth aspect of the present invention, rotational movement of the rotating shaft is assuredly limited to within the prescribed range of rotation, and the precision of the rotational movement can be assured to be good.
Also, according to the abovementioned sixth aspect of the present invention, molding can be performed easily in the state in which the rotating shaft is outside the prescribed range of rotation, and the operation of assembly after molding is simplified.
Examples in which the shaft support structure according to the present invention is applied to a cup holder are described below while referring to the drawings. This cup holder can be placed, for example, in a center console box provided between the driver's seat and the front passenger seat of a passenger car.
As illustrated in
The container-holding mechanisms 4 are arranged on a perimeter wall outside the container-receiving part 2 (on the side away from the other container-receiving part 2). The container-holding mechanism 4 has: a flap 11 made of synthetic resin, being provided to move in and out freely from an opening 5 on the container-receiving part 2, and pressing the beverage can, or the like (not illustrated) toward the perimeter wall inside the container-receiving part 2; a pair of shaft-bearing members 12 and 13, projecting sideways from the holder body 3 so as to confront each other, and supporting the flap 11 to rotate freely; and a torsion coil spring 14 made of metal, for urging the flap 11 toward the inside of the container-receiving part 2.
The flap 11, as illustrated in
The left rotating shaft 24 has a round-columnar form, and an annular raised part 27, for contacting with the left shaft-bearing member 12 (first support wall 31) and preventing rattling of the flap 11, is formed on the periphery thereof. Also, the right rotating shaft 25 has a vertically long noncircular cross-section, and a slit 28 is formed to be cut in from a leading end toward a base end of the right rotating shaft so as to divide the right rotating shaft 25 vertically. Also, an expanded-diameter part 29, having an expanded diameter in a diameter direction (vertical direction) thereof, is provided on the base end side of the right rotating shaft 25. The right rotating shaft 25, excluding the expanded-diameter part 29, has the same external shape (tapered external shape) as that of a held part 37 to be described in detail, or smaller on the leading end side thereof.
The left shaft-bearing member 12 has a roughly parallelepiped form having an open lower face, and has a first support wall 31, being a vertical wall, extending in the vertical direction on the inside (right shaft-bearing member 13 side) thereof as illustrated in
Also, the right shaft-bearing member 13 has a roughly parallelepiped form having an open right face, and has a second support wall 35 facing opposite the first support wall 31 of the left shaft-bearing member 12. A right shaft-bearing opening 36, in which the right rotating shaft 25 of the flap 11 is inserted, is formed on the second support wall 35. The right shaft-bearing opening 36 is a noncircular long hole extending in the left to right direction, and a state of holding of the right rotating shaft 25 is changed in accordance with a rotational position of the flap 11 (right rotating shaft 25), as is to be described. The right shaft-bearing opening 36 is formed on a thickened part on the second support wall 35, and a held part 37 (see
A torsion coil spring 14 is bent in a manner so that an arm 41 on one side of a coil part 40 crosses the center thereof, and a linear arm 42 is placed extending from the other side of the coil part 40, as illustrated in
The flap 11 is urged by the torsion coil spring 14 toward the inside of the container-receiving part 2, and is held in an initial state illustrated in
Meanwhile, when a beverage can, or the like, is inserted in the container-receiving part 2, the flap 11 is pressed and retracts toward the outside of the container-receiving part 2 in opposition to the urging force of the torsion coil spring 14, as illustrated in
As illustrated in
By such shaft support structure, in the state in which the right rotating shaft 25 is held in the right shaft-bearing opening 36, a distance from the center C of rotation to the maximum outer perimeter edge parts 51 and 52 and a distance from the center C of rotation to the minimum inner perimeter edge parts 53 and 54 become substantially the same. In other words, in the case when the right rotating shaft 25 is within the prescribed range of rotation, rattling in the diameter direction of the right rotating shaft 25 (flap 11) is prevented, and the precision of rotational movement can be assured to be good. Here, the prescribed range of rotation in the present embodiment is the range between the rotational position illustrated in
The maximum outer perimeter edge parts 51 and 52 and the minimum inner perimeter edge parts 53 and 54 can take various forms provided that at least the distances from the center C of rotation are the same. In the present embodiment, the maximum outer perimeter edge parts 51 and 52 and the minimum inner perimeter edge parts 53 and 54 have arc-form shapes having the same curvature as each other, whereby the structures of the right rotating shaft 25 and the right shaft-bearing opening 36 are simplified, and the right rotating shaft 25 can be rotated with higher precision within the prescribed range of rotation.
Also, the maximum outer perimeter edge parts 51 and 52 (the same also with respect to the minimum inner perimeter edge parts 53 and 54) respectively are arranged in symmetric positions based on the center C of rotation in a state being space apart from each other. By this, the range of rotation in which the precision of rotational movement of the right rotating shaft 25 can be assured to be good can be assured more widely. In the present embodiment, an example in which two maximum outer perimeter edge parts 51 and 52 are provided is presented, but the present invention is not limited to this, and the number of maximum outer perimeter edge parts 51 and 52 can be suitably changed (the same goes also with respect to the minimum inner perimeter edge parts 53 and 54). For example, the maximum outer perimeter edge parts 51 and 52 may be configured respectively with a plurality of outer perimeter edge parts having shorter arcs.
Also, an annular raised part 27 having a radius larger than that of the left shaft-bearing opening 32 is formed on the perimeter of the left rotating shaft 24. Meanwhile, the right rotating shaft 25 has an expanded-diameter part 29 projecting further outward than the maximum outer perimeter edge parts 51 and 52 of the held part 37 in the diameter direction. By this, the annular raised part 27 and the expanded-diameter part 29 respectively contact with the end face of the left shaft-bearing opening 32 (front face of first support wall 31) and the end face of the right shaft-bearing opening 36 (front face of second support wall 35), whereby movement of the flap 11 in the axial direction is restricted (that is, rattling in the axial direction between the first support wall 31 and the second support wall 35 is prevented).
Also, by the coupling between the rotation-restricting pin 26 and the rotation-restricting hole 38, rotational movement of the right rotating shaft 25 is assuredly limited to within the prescribed range of rotation, and the precision of the rotational movement can be assured to be good.
In the present embodiment, the rotating shafts of the flap 11 are configured with two rotating shafts (left rotating shaft 24 and right rotating shaft 25), but these can also be configured integrally as one rotating shaft. Also, the left rotating shaft 24 and the left shaft-bearing opening 32 may have the same structure, respectively, as the right rotating shaft 25 and the right shaft-bearing opening 36. Furthermore, the right shaft-bearing opening 36 does not necessarily have to be a closed hole, provided that it has at least the minimum inner perimeter edge parts 53 and 54 as described above. For example, the right shaft-bearing opening may be in a slit form in which at least one part is open, or the like, as indicated by the double-dotted line in
In the cup holder 1 having the above configuration, the left and right shaft-bearing members 12 and 13 (here, integrally formed with the holder body 3) and the flap 11 is produced by injection molding of synthetic resin in a provisionally assembled state in which the right rotating shaft 25 is inserted with play in the right shaft-bearing opening 36, as illustrated in
By this, in relation to the molds used for injection molding, the holder body 3 and the flap 11 can be simultaneously molded in the same mold, for example, by arranging a stationary mold below the shaft-bearing members 12 and 13, arranging a mobile mold above the shafts, and furthermore arranging a slider that is movable from the right of the right shaft-bearing member 13 in parallel with the right rotating shaft 25. In this case, the right rotating shaft 25 can be molded in a state being spaced apart from the right shaft-bearing opening 36, by inserting the slider in the gap G (in the present embodiment, a gap being formed with a constant size at the periphery of the right rotating shaft 25). Also, because the shaft-bearing members 12 and 13 and the flap 11 after molding are in a provisionally assembled state, it is easy for the operator to assemble the container-holding mechanisms 4.
A cup holder according to a second embodiment is next described while referring to
In the cup holder 1 according to the second embodiment, the configuration of the torsion coil spring 14 for urging the flap 11 and the configuration of the right rotating shaft 25 are different from the case of the first embodiment. The torsion coil spring 14 has a double-torsion shape in which two coil parts 40 and 40 are connected in series directly, as illustrated in
Also, as illustrated in
The present invention has been described in detail based on specific embodiments, but these embodiments are merely illustrations, and the present invention is not to be limited by these embodiments. The shaft support structure according to the present invention is not limited to the above-described cup holder, and can be used for various uses (for example, pipe clamp, lid part of a compartment, hinge part of a glove compartment, and the like), provided that there is at least a shaft support structure for supporting a rotating shaft and there are two members constituted by molded articles. Also, the material of the members is not limited to resin and may be metal, or the like, and the molding process also is not limited to injection molding, and die casting, or the like, can also be applied. Also, it is not the case that all of the constituent elements of the shaft support structure according to the present invention illustrated in the above embodiments are necessary, and the constituent elements can be used selectively within a range not deviating from the scope of the present invention.
1 Cup holder
2 Container-receiving part
3 Holder body
4 Container-holding mechanism
11 Flap (rotating member)
12 Left shaft-bearing member
13 Right shaft-bearing member
14 Torsion coil spring
24 Right rotating shaft
25 Left rotating shaft
26 Rotation-restricting pin (coupling part)
32 Left shaft-bearing opening
36 Right shaft-bearing opening
37 Held part
38 Rotation-restricting hole (corresponding coupling part)
51, 52 Maximum outer perimeter edge part
53, 54 Minimum inner perimeter edge part (corresponding inner perimeter edge part)
C Center of rotation
G Gap
Number | Date | Country | Kind |
---|---|---|---|
2010-048265 | Mar 2010 | JP | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
---|---|---|---|---|
PCT/JP2011/001065 | 2/24/2011 | WO | 00 | 9/13/2012 |