JP5296507B2 - Armrest - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an armrest which prevents breakage of a support mechanism and lowering of holding force. <P>SOLUTION: A support mechanism 50 includes a fixed support part 51 unrotatably provided with respect to a seat to rotatably support the armrest body 10, and a variable support part 52 which is provided at the fixed support part 51 and whose attitude is variable in the rotation direction of the armrest body 10. The support mechanism 50 also includes a holding part 53 with a plurality of holding tooth parts 75 which is provided at the armrest body 10 while facing the rotation center side of the armrest body 10 and arranged in an internally toothed gear shape centering on the rotation center. Further, the support mechanism 50 includes a stopper part 54 provided on the circumferential surface of the variable holding part 52, arranged in an outer gear shape correspondingly to the internally toothed gear formed with the holing tooth part 75, and having a plurality of support tooth parts 77 to be meshed with the holding tooth parts 75 in the holding attitude of the variable support part 52. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to an armrest provided with a support mechanism that rotatably supports an armrest body as a core member with respect to a seat.

  An armrest on which an arm is hung is provided on a seat attached to a vehicle such as a passenger car or on the side of the seat as a comfortable equipment that allows an occupant using the seat to maintain a comfortable posture. For example, as shown in FIG. 11, the armrest AR1 mounted on the seat S is rotatably attached to the side of the seat back S1 of the seat S and extends forward from the seat back S1 to a substantially horizontal posture when in use. It is configured to be used and retracted to a retracted posture standing on the side surface of the seat back S1 when not in use. By the way, the occupants of various physiques sit on the seat S, and the inclination angle of the seat back S1, the postures of the occupants, and the like are various, so the support mechanism 91 having a function of adjusting the angle of the armrest body 90 is provided. By arranging, the angle at the time of use of armrest AR1 respond | corresponds to the desire to adjust according to a passenger | crew.

  For example, the armrest includes a disk that is fixed to the armrest and has ratchet teeth on the peripheral surface, and a mounting plate that is fixed to a support shaft that is fixed to the seat, and ratchet claws provided on the mounting plate are attached to the ratchet teeth of the disk. Some have a so-called ratchet structure support mechanism configured to be able to hold the armrest at a predetermined angle by engaging from one direction (see Patent Document 1).

  As another armrest, a ratchet gear fixed to the seat and provided with a gear portion, a latch provided on the armrest and provided with a blade portion, and a so-called ratchet structure supporting mechanism provided with an elastic member is proposed. (See Patent Document 2). The support mechanism disclosed in Patent Document 2 is configured such that a plurality of blades in the blade portion of the latch are engaged with and disengaged from the gear portion of the ratchet gear when the latch is displaced, and the armrest can be held at a predetermined angle.

Further, as another armrest, a drum fixed to the seat, a case fixed to the armrest and rotatable relative to the drum, one end fixed to the case and wound around the drum, and the other end free. There has been proposed a so-called friction structure supporting mechanism having a coil spring (see Patent Document 3). In the support mechanism disclosed in Patent Document 3, when the armrest is rotated downward, the coil spring is tightened, and the torque of the coil spring makes the armrest unrotatable and held at a predetermined angle. Sometimes the coil spring loosens and the armrest is allowed to rotate.
Japanese Patent No. 2582264 JP-A-2005-65786 Japanese Patent No. 3891584

  In the support mechanism of the ratchet structure disclosed in Patent Document 1, when a load is applied to the armrest, stress concentrates on the contact portion between the rotation shaft portion of the ratchet pawl and the ratchet teeth, and a force is applied in the tangential direction of the pitch circle. . That is, since the stress acts so as to coincide with the direction of the shearing force of the ratchet teeth, there is a problem that the ratchet teeth are easily chipped. The angle adjusting mechanism of the ratchet structure disclosed in Patent Document 2 can disperse the stress applied to the blade portion because the blade portion of the latch and the gear portion of the ratchet gear are engaged by a plurality of blades. Similarly, since the stress acts so as to coincide with the direction of the shearing force of the gear portion of the ratchet gear, there is a problem that the gear portion is likely to be chipped. In addition, the blade portion of the latch and the gear portion of the ratchet gear have inclined surfaces, and the inclined surfaces come into contact with each other unless the blade portion and the gear portion mesh with each other, and a load is applied to the armrest. There is a problem that the blade portion of the latch is easily detached from the gear portion of the ratchet gear. Furthermore, although the angle adjustment mechanism of the friction structure disclosed in Patent Document 3 is a simplified structure, if it is used repeatedly, the holding force is reduced due to wear and deformation of the hinge shaft, and a load is applied to the armrest. When added, the problem of the armrest rotating downward is inherent.

  Therefore, in the present invention, in view of the above-mentioned problems inherent in the armrest according to the prior art, it has been proposed to suitably solve these problems, and an armrest that prevents breakage of the support mechanism and reduction in holding force is provided. The purpose is to provide.

In order to solve the problem and achieve the intended purpose, the invention according to claim 1
An armrest having a support mechanism that supports the armrest body so as to be rotatable in the vertical direction with respect to the seat,
The support mechanism is
A fixed support portion that is provided so as not to rotate with respect to the seat and supports the armrest body rotatably;
A variable support portion disposed on the fixed support portion and displaceable in a rotational direction of the armrest body;
A holding portion having a plurality of holding teeth arranged in an internal gear shape centered on the rotation center, the armrest main body facing the rotation center side of the armrest main body;
Provided on the peripheral surface of the variable support portion, and in the holding posture of the variable support portion, in line with the external gear shape centering on the rotation center corresponding to the internal gear formed by the holding tooth portion, A stopper portion having a plurality of support tooth portions capable of meshing;
A restriction portion provided on the fixed support portion and restricting displacement of the variable support portion in the holding posture in the downward rotation direction of the armrest body;
When the armrest body is rotated downward, the support tooth portion is guided by the tooth shape while being in contact with the holding tooth portion, and the armrest body is rotated in the downward direction so that the variable support portion is in the holding posture. When the armrest body is rotated upward, the support tooth portion is guided by the tooth shape of each other while being in contact with the holding tooth portion, so that the meshing of both the tooth portions can be released. The armrest body is configured to be displaced in the upward rotation direction so as to have a proper posture.

  Therefore, according to the first aspect of the invention, when the armrest body is rotated downward, the holding tooth portion of the holding portion and the support tooth portion of the stopper portion mesh with each other as the internal gear and the external gear, so that the variable support portion is As the holding posture, the posture of the armrest body can be reliably held. In addition, when the armrest body is rotated upward, the holding tooth portion and the support tooth portion are arranged by bringing the variable support portion into a posture capable of releasing the meshing of both tooth portions by contact between the holding tooth portion and the support tooth portion. Is released and the armrest body is appropriately rotated upward. Since the holding portion and the stopper portion mesh as a gear, chipping of the holding tooth portion and the support tooth portion is unlikely to occur and damage to the support mechanism can be prevented.

The invention described in claim 2
The holding portion and the stopper portion of the variable support portion in the holding posture are in a relationship in which the holding tooth portion and the supporting tooth portion mesh on the same reference circle,
The holding tooth portion and the supporting tooth portion are formed in a tooth profile that tapers from the tooth base toward the tooth tip so that the pressure angle at the pitch point between the holding tooth portion and the supporting tooth portion is an acute angle. The gist.
Therefore, according to the second aspect of the invention, since the holding tooth portion of the holding portion and the support tooth portion of the stopper portion are formed in a tapered tooth shape, both the tooth portions can mesh smoothly. In addition, since the pressure angle at the pitch point of the holding tooth portion and the support tooth portion is an acute angle, the stress acting on both tooth portions differs by an angle difference equivalent to the pressure angle with respect to the shear direction at the root of these tooth portions. It acts in the direction, and the tooth chipping of the tooth portion can be appropriately prevented.

The invention according to claim 3
The variable support portion is disposed rotatably with respect to the fixed support portion,
The gist of the invention is that the rotation center of the variable support portion is configured to be spaced apart from the line connecting the rotation center of the armrest body and the pitch point of both tooth portions in the direction in which the armrest body rotates downward. .
Therefore, according to the invention of claim 3, when a force in the downward rotation direction is applied to the armrest body, the variable support portion rotates in a direction in which the distance between the rotation center of the variable support portion and the pitch point decreases. Thus, the stopper portion is pressed toward the holding portion, and the support tooth portion of the stopper portion and the holding tooth portion of the holding portion are reliably engaged with each other. In addition, when a force in the upward rotation direction is applied to the armrest body, the variable support portion rotates in a direction in which the interval between the rotation center of the variable support portion and the pitch point increases, and the stopper portion is removed from the holding portion. As a result, the engagement between the support tooth portion of the stopper portion and the holding tooth portion of the holding portion is appropriately released.

The invention according to claim 4
The support mechanism includes a biasing member that biases the variable support portion toward the holding posture.
Therefore, according to the fourth aspect of the invention, the variable support portion can be held in the holding posture.

The invention described in claim 5
The support mechanism is provided at a rear end of the holding portion in the upward rotation direction of the armrest body, and abuts on the stopper portion when the armrest body rotates upward, so that the support tooth portion and the holding tooth portion cannot be engaged with each other. A first switching part for displacing the variable support part to a retreating position;
Provided in the variable support portion, the variable support portion is provided so as to extend on a displacement locus of the first switching portion in the retracted posture, and the first switching portion abuts when the armrest body is rotated downward. And a second switching portion that displaces the variable support portion to the holding posture.
Therefore, according to the fifth aspect of the invention, the variable support portion is displaced from the holding posture to the retracted posture while the armrest body is rotated upward, and the support tooth portion of the stopper portion and the holding tooth portion of the holding portion are engaged. To release. Accordingly, when the armrest is rotated downward, the support tooth portion of the stopper portion and the holding tooth portion of the holding portion do not mesh with each other, so that the armrest can be smoothly rotated downward. In addition, the variable support portion is displaced from the retracted posture to the holding posture while the armrest main body is rotated downward, so that the support tooth portion of the stopper portion and the holding tooth portion of the holding portion mesh with each other. Retained.

  According to the armrest according to the present invention, the support tooth portion of the stopper portion and the holding tooth portion of the holding portion mesh with each other as the internal gear and the external gear, so that the armrest body can be appropriately held. In addition, since the support tooth portion and the holding tooth portion are provided with a pressure angle, the stress acting at the pitch point of both tooth portions acts in a direction different from the shear direction at the root of these tooth portions, and the tooth portions It is possible to suitably prevent tooth missing. Moreover, when the force of a downward rotation direction acts on an armrest main body, the meshing degree of the support tooth part of a stopper part and the holding tooth part of a holding | maintenance part will become strong, and the holding power fall of an armrest main body can be prevented.

  Next, the armrest according to the present invention will be described below with reference to the accompanying drawings by giving a preferred embodiment. In the embodiment, an armrest attached to the left side portion of the seat back will be described as an example. In the embodiment, in a use state (indicated by a solid line in FIG. 11) extending substantially horizontally from the seat back S1 to the front of the vehicle, the vehicle longitudinal direction is the “longitudinal direction” of the armrest, and the vertical direction is the “short direction”. The left-right direction is referred to as the “lateral width direction”. Further, in the state of use, the side facing the front of the vehicle is the “front end side” of the armrest, the side facing the rear of the vehicle is the “rear end side”, and the side close to the seat back is the “seat back near side”, The side opposite to the seat back is referred to as the “seat back far side”.

  FIG. 1 is a side view showing the armrest AR of the embodiment in a state in which the skin material 14 and the cushion material 12 are transparently shown, FIG. 2 is a sectional view taken along the line II-II in FIG. 1, and FIG. FIG. The armrest AR of the embodiment includes a synthetic resin armrest body 10 as a core material, a cushion material 12 that covers the armrest body 10, and a skin material 14 that covers the cushion material 12. The armrest body 10 is attached to the seat back S1 using a support bolt B shown in FIG. 2 and the like, and is displaced in posture while rotating between a use position and a non-use position. The skin material 14 is made of the same material as the sheet skin material, and is made of synthetic resin such as polyvinyl chloride (PVC), fabric such as fabric or tricot, or genuine leather. The cushion material 12 is a foamed material such as urethane foam or sponge, and is foam-molded between the armrest body 10 and the skin material 14 by a foaming mold in which the armrest body 10 and the skin material 14 are inserted.

  As shown in FIGS. 1 and 2, the armrest main body 10 is configured by assembling the main body member 20 and the cover member 40 from the lateral width direction, and has a rigidity required for the armrest AR as a structure that receives a load applied to the armrest AR. Is secured. The armrest body 10 has a rear portion defined as a housing portion 10A for housing the support mechanism 50 at a position about 1/3 from the rear end in the longitudinal direction, and the front portion extends forward from the seat back S1. It becomes the support part 10B which takes out and supports an arm.

  The main body member 20 is a synthetic resin member that is injection-molded from a reinforced resin containing, for example, about 40% glass fiber in polyamide (PA). A partition wall 21 extending in the lateral width direction is formed, and is partitioned by the partition wall 21 into the accommodating portion 10A and the support portion 10B described above. As shown in FIGS. 1 and 3, in the accommodating portion 10 </ b> A, a plate-like first base wall portion 22 that extends from the seat back far side edge of the partition wall 21 to the rear end side is formed, In the support portion 10 </ b> B, a long plate-like second base wall portion (base wall portion) 23 extending from the seatback near side edge of the partition wall 21 to the front end side is formed. A main body outer peripheral wall portion (first projecting wall portion) 24 extending in the lateral width direction is provided on the outer peripheral end edges of the first base wall portion 22 and the second base wall portion 23 on the entire periphery of the main body member 20. It is formed over. That is, the outer peripheral wall portion 24 has the same width dimension over the entire circumference, and extends from the first base wall portion 22 toward the seat back side in the accommodating portion 10A, and in the support portion 10B, Two base wall portions 23 extend to the far side of the seat back.

  The first base wall portion 22 is formed with a circular recessed portion 25 that is recessed toward the seat back, and the first bolt insertion through which the support bolt B described above is inserted at the bottom center of the recessed portion 25. A hole 26 is formed. As shown in FIGS. 2 to 5, an outer peripheral rib 28 that protrudes in the circumferential direction over the entire circumference is formed in the seat back far side portion of the main body outer peripheral wall 24. The extension amount of the outer peripheral rib 28 from the main body outer peripheral wall portion 24 is set to be equal to the thickness of the cover outer peripheral wall portion 42 of the cover member 40 described later. Further, the second base wall portion 23 is provided with an intermediate protruding wall portion 30 extending in the longitudinal direction of the main body member 20 as will be described later. That is, the support portion 10B is arranged in parallel with a short distance in the short direction, and three projecting wall portions each having a base end continuous with the second base wall portion 23, that is, the main body outer peripheral wall portion 24, the middle The protruding wall portion 30 and the main body outer peripheral wall portion 24 are formed in a shape extending in the longitudinal direction.

  As shown in FIG. 3, the outer peripheral wall 24 of the main body described above is located on the outer surface of the armrest main body 10 at the distal end on the far side of the seat back, and the head of the occupant may come into contact therewith. It is formed into an R chamfered shape with a radius of 3.2 mm or more in accordance with the provision of “inner protrusion” in the related “ECE: ECONOMIC COMMISSION FOR EUROPE REGULATIONS”. That is, at the portion of the main body outer peripheral wall portion 24 that is positioned at the support portion 10B, the end edge of the main body outer peripheral wall portion 24 opposite to the intermediate protruding wall portion 30 at the distal end of the seat back is formed in an R chamfered shape. ing.

  As shown in FIGS. 1 to 4, the intermediate protruding wall portion 30 is formed on the second base wall portion 23 of the main body member 20 at a distance from the main body outer peripheral wall portion 24. As shown in FIG. 3, the intermediate projecting wall portion 30 has a second surface VF extending from an opening region VF sandwiched between the front end portions of the main body outer peripheral wall portions 24 and 24 facing in the short-side direction. The tip is formed so as to protrude in a direction away from the base wall portion 23. That is, the intermediate protruding wall portion 30 is formed so as to bulge an intermediate portion in the short direction of the second base wall portion 23 in the seat back far side direction and extend in the longitudinal direction. It is formed from a pair of upright wall portions 31, 31 that are spaced apart from each other in the short direction, which is the side-by-side direction, and that opposes each other, and a top wall portion 32 that connects the tips of the upright wall portions 31, 31 and extends in the longitudinal direction. ing. As shown in FIG. 5, the compatible wall portions 31, 31 are inclined so as to gradually approach each other from the second base wall portion 23 side toward the top wall portion 32 side. Accordingly, the intermediate projecting wall portion 30 has a mountain-shaped cross section broken in the short direction.

  Further, as shown in FIGS. 1 and 3, etc., the main body outer peripheral wall portions 24, 24 facing each other with the intermediate projecting wall portion 30 interposed therebetween are spaced apart from each other in the short direction by the opposing standing wall portions 31, 31. It forms so that it may increase gradually as it goes to a front-end | tip from the base wall part 23 side. In addition, the interval between the main body outer peripheral wall portions 24, 24 in the short direction is formed to be the same from the second base wall portion 23 side to the tip. Therefore, since the armrest body 10 has no undercut, the molded armrest body 10 can be easily removed without using a slide mold in injection molding. The main body outer peripheral wall portions 24, 24 are formed so that the distance in the short direction from the opposing standing wall portions 31, 31 becomes the same (becomes parallel) from the second base wall portion 23 side toward the tip. Even so, the armrest body 10 can be easily removed from the mold. Moreover, you may form so that the space | interval in the transversal direction of the main body outer peripheral wall parts 24 and 24 may increase gradually as it goes to the front-end | tip from the 2nd base wall part 23 side.

  The above-described intermediate protruding wall portion 30 protrudes toward the seat back far side of the armrest body 10, and there is a possibility that the occupant's head may come into contact with the top portion (tip). R-chamfered shape. That is, the central edge portions 33 and 33 extending in the longitudinal direction at the boundary portions between the top wall portion 32 and the standing wall portions 31 and 31 are formed in an R chamfer shape. The compatible wall portions 31 and 31 and the top wall portion 32 are formed to have substantially the same thickness as the main body outer peripheral wall portion 24. Therefore, even if each center edge part 33 and 33 is made into R chamfering shape with a radius of 3.2 mm or more, it is not necessary to enlarge the thickness of the compatible wall parts 31 and 31 and the top wall part 32. FIG.

  The cover member 40 is a synthetic resin member formed by injection molding from, for example, acrylonitrile / butadiene / styrene (ABS). The cover member 40 includes a plate-like portion 41 that covers the main body member 20 from the seat back near side, and extends along the outer peripheral edge of the plate-like portion 41 and extends from the plate-like portion 41 to the seat back far side. And a cover outer peripheral wall portion 42 formed to protrude. The plate-like portion 41 is formed in the same outline shape as the extending shape of the main body outer peripheral wall portion 24 of the main body member 20, so that the cover outer peripheral wall portion 42 contacts the outer peripheral surface of the main body outer peripheral wall portion 24. It is formed to extend. Therefore, when the cover member 40 is assembled to the main body member 20, as shown in FIGS. 2 and 3, the plate-like portion 41 covers the housing portion 10A and abuts against the second base wall portion 23, The cover outer peripheral wall portion 42 comes into close contact with the main body outer peripheral wall portion 24 and is aligned with the outer peripheral rib 28 described above. A circular opening 43 through which a support boss 68 of a sub bracket 56 constituting the support mechanism 50 described later is inserted is formed in a portion of the plate-like portion 41 corresponding to the accommodating portion 10A. In addition, the edge part 44 which is a boundary part of the plate-shaped part 41 of the cover member 40 and the cover outer peripheral wall part 42 is formed in R chamfering shape with a radius of 3.2 mm or more.

  The support mechanism 50 in the armrest AR of the embodiment is provided so as not to rotate with respect to the seat back S1 of the seat S, as shown in FIGS. 2, 4 and 5, and the armrest body 10 is attached to the seat back S1. A fixed support portion 51 that is rotatably supported in the vertical direction, and a variable support portion 52 that is disposed on the fixed support portion 51 and can be displaced in the rotational direction of the armrest body 10 are provided. Further, the support mechanism 50 includes a holding portion 53 provided on the armrest body 10 and a stopper portion 54 provided on the peripheral surface of the variable support portion 52. The support mechanism 50 holds the posture of the armrest body 10 by the holding tooth portion 75 of the holding portion 53 and the support tooth portion 77 of the stopper portion 54 meshing as tooth portions of the internal gear and the external gear on the same reference circle. In addition, the armrest body 10 is allowed to rotate up and down by releasing the engagement between the holding tooth portion 75 and the support tooth portion 77.

  As shown in FIGS. 2 and 4, the fixed support portion 51 is disposed outside the main bracket 55 disposed in the housing portion 10 </ b> A of the armrest body 10 and the seatrest near the armrest AR. The sub bracket 56 is in contact with the side surface of the back S1. The main bracket 55 is formed with a substantially cross-shaped fitting hole 57, and the sub bracket 56 is formed with a substantially cross-shaped fitting boss 58. Therefore, the main bracket 55 and the sub bracket 56 are connected to each other in a state where the plate-like portion 41 of the cover member 40 is sandwiched between the main bracket 55 and the sub bracket 56 by inserting and fitting the fitting boss portion 58 into the fitting hole portion 57. .

  As shown in FIGS. 4 and 5, the main bracket 55 is a plate-like member having a complicated contour shape, and in a state of being accommodated in the accommodating portion 10A, a circular connecting plate portion 59 positioned on the rear end side. And a support portion 60 on which the variable support portion 52 described above is disposed. The connecting plate portion 59 is formed with a circular boss portion 61 projecting toward the sub bracket 56 side, and the above-described fitting hole portion 57 is formed in the boss portion 61. The support portion 60 is formed with a circular mounting hole 62 for rotatably supporting the variable support portion 52, and an arcuate slide guide for supporting the gear head portion 74 provided on the variable support portion 52 from below. A surface 63 is formed. Further, a support piece 64 extending in the distal direction is provided on the upper portion of the support portion 60, and a first locking hole 65 for locking one leg TS1 of a torsion spring (biasing member) TS described later is formed. Is formed. Reference numeral 66 is located on the distal end side of the sliding guide surface 63 and is a support receiver that supports the gear head portion 74 when the variable support portion 52 is displaced to a holding posture (see FIG. 8B) described later. Part (regulatory part). That is, the support receiving portion 66 restricts the variable support portion 52 in the holding posture from being displaced in the downward rotation direction of the armrest body 10. Reference numeral 67 denotes a stopper piece that comes into contact with the end surface of the variable support portion 52 when the variable support portion 52 is displaced to a retracted posture (see FIG. 8A) described later. Reference numeral 76 denotes a contact portion that contacts a bulging portion 74A provided at the rear portion of the gear head portion 74 when the variable support portion 52 is displaced to the retracted posture.

  As shown in FIGS. 2 and 4, the sub bracket 56 protrudes into the armrest body 10 from a circular support boss 68 that fits into the circular opening 43 of the cover member 40 and an end surface of the support boss 68. And the fitting boss 58. A second bolt insertion hole 69 through which the support bolt B passes is formed at the center of the support boss portion 68 and the fitting boss portion 58.

  The variable support portion 52 has a rotation support boss portion 70 that fits into an attachment hole 62 formed in the main bracket 55 of the fixed support portion 51 on the side surface, and is attached to the main bracket 55 from the far side of the seat back. Then, the variable support portion 52 rotates in the rotation direction of the armrest body 10 with respect to the fixed support portion 51 around the rotation support boss portion 70 fitted in the mounting hole 62, and holds the holding posture (see FIG. 8B). And it can be displaced to a retracted posture (see FIG. 8A). The variable support portion 52 is formed with an outer rib 71 extending in a required width in the outer portion, and has rigidity that does not break even when a force applied to the armrest AR is applied. A contact piece (second switching portion) 72 extending toward the distal end is formed at the lower portion of the variable support portion 52. Further, in the vicinity of the gear head portion 74 provided in the variable support portion 52, a second locking hole 73 for locking the other leg portion TS2 of the torsion spring TS described above is formed.

  As shown in FIGS. 2 and 5, the holding portion 53 is formed integrally with the first base wall portion 22 at a portion adjacent to the partition wall 21 in the housing portion 10 </ b> A of the armrest body 10. The holding portion 53 is provided in an arc shape centering on the rotation center C1 of the armrest body 10 (the axis center of the support bolt B) and extends in the short direction, and a plurality of the holding portions 53 face the rotation center C1. It has 10 holding teeth 75 (in the embodiment, 10). That is, each holding tooth part 75 is formed in the state arranged in the shape of an internal gear centering on the rotation center C <b> 1 of the armrest body 10, and the holding part 53 has a meshing region G extending in the short direction of the armrest body 10. I have. Each holding tooth portion 75 is formed in, for example, an involute tooth profile with a pressure angle α = 20 °, and is formed in a tooth profile that tapers from the tooth root toward the tooth tip.

  The stopper portion 54 is provided on the peripheral surface of the gear head portion 74 provided on the upper portion of the variable support portion 52. In the holding posture of the variable support portion 52, the stopper portion 54 is arranged in an external gear shape centering on the rotation center C1 of the armrest body 10 corresponding to the internal gear formed by the holding tooth portion 75 of the holding portion 53. A plurality of (three in the embodiment) support teeth 77 that can mesh with the holding teeth 75 are provided. These supporting tooth portions 77 are formed in an involute tooth profile with a pressure angle α = 20 °, for example, and are formed in a tooth shape that tapers from the tooth root toward the tooth tip. It is considered as a module. That is, the holding portion 53 and the stopper portion 54 provided on the variable support portion 52 in the holding posture are in a relationship in which the holding tooth portion 75 and the support tooth portion 77 mesh with each other on the same reference circle. The holding tooth portion 75 and the support tooth portion 77 are moved from the tooth base to the tooth tip so that the pressure angle α at the pitch point P (see FIG. 7) between the holding tooth portion 75 and the support tooth portion 77 is 20 °. It is formed in a tooth profile that tapers toward. In the support mechanism 50 of the embodiment, the meshing position of the stopper portion 54 with respect to the holding portion 53 can be changed in nine stages in the meshing region G. Therefore, the armrest AR of the embodiment can be held in nine stages with different inclination angles.

  As shown in FIGS. 6 and 7, the first spring hole 65 formed in the support piece 64 of the main bracket 55 and the second lock hole 73 formed in the variable support portion 52 have the above-described torsion spring TS. Is built. In the mounted state in which the leg portions TS1 and TS2 are locked in the first locking hole 65 and the second locking hole 73, the torsion spring TS always increases the distance between the tips of the leg portions TS1 and TS2. It is energized in the direction to do. Then, as shown in FIG. 6, the distance between the first locking hole 65 and the second locking hole 73 changes in the process in which the variable support portion 52 moves between the holding posture and the retracting posture. ing. That is, when the variable support portion 52 is positioned approximately in the middle between the holding posture and the retracting posture, the interval between the first locking hole 65 and the second locking hole 73 is minimized, so that the variable support portion 52 is in the holding posture. When positioned and in the retracted position, the distance between the first locking hole 65 and the second locking hole 73 increases. Therefore, when the position where the first locking hole 65 and the second locking hole 73 are at the minimum interval is referred to as the “switching position” of the variable support portion 52, the variable support portion 52 is positioned closer to the holding posture than the switching position. In this case, the variable support portion 52 is displaced to the holding posture and held in the holding posture by the biasing force of the torsion spring TS. Further, when the variable support portion 52 is positioned on the retracted posture side of the switching position, the variable support portion 52 is displaced to the retracted posture and held in the retracted posture by the biasing force of the torsion spring TS. It has become.

  In the support mechanism 50 of the embodiment, as shown in FIG. 7, the rotation center C <b> 2 of the variable support portion 52 has a pitch point P that is the meshing position of the rotation center C <b> 1 of the armrest body 10 and both the tooth portions 75 and 77. It is comprised so that it may be spaced apart and located in the downward rotation direction of the armrest main body 10 from the line L which ties. Thereby, the space | interval N of the rotation center C2 of the variable support part 52 and the pitch point P of both the tooth parts 75 and 77 is comprised so that it may reduce gradually in the downward rotation direction of the armrest main body 10. FIG. Therefore, when a downward rotating force is applied to the armrest body 10, the support tooth portion 77 is guided in a mutual waveform while being in contact with the holding tooth portion 75, so that the variable support portion 52 assumes a holding posture. 10 in the downward rotation direction. For this reason, the stopper part 54 comes to be pressed against the holding part 53, the degree of engagement between the support tooth part 77 of the stopper part 54 and the holding tooth part 75 of the holding part 53 is strengthened, and both the tooth parts 75, 77 are securely connected. It is designed to mesh. The displacement of the holding portion 53 in the downward rotation direction of the armrest body 10 is restricted over the meshing region G where the support tooth portion 77 of the stopper portion 54 meshes with the holding tooth portion 75 of the holding portion 53, and this meshing In the region G, the posture of the armrest body 10 can be maintained.

  On the other hand, the interval N between the rotation center C2 of the variable support portion 52 and the pitch point P of both the tooth portions 75 and 77 is configured to gradually increase in the upward rotation direction of the armrest body 10. Accordingly, when a force for rotating upward is applied to the armrest body 10, the support tooth portion 77 is guided by the mutual tooth shape under the contact with the holding tooth portion 75, and the variable support portion 52 is moved between the tooth portions 75 and 77. The armrest body 10 is displaced in the upward rotation direction so as to be in a posture capable of releasing the meshing. For this reason, the stopper part 54 comes to be separated from the holding part 53, and the meshing between the support tooth part 77 of the stopper part 54 and the holding tooth part 75 of the holding part 53 is released. The displacement of the holding portion 53 in the upward rotation direction of the armrest body 10 is possible in a state where the support tooth portion 77 of the stopper portion 54 is in contact with the holding tooth portion 75 of the holding portion 53. In the state where the support tooth portion 77 of the stopper portion 54 is in contact with the holding tooth portion 75 of the holding portion 53, the variable support portion 52 is not displaced up to the switching position described above, and the support tooth portion 77 and the holding tooth portion 75. When the abutment between the two ends is released, the variable support portion 52 is displaced to the holding posture by the biasing force of the torsion spring TS, and the holding tooth portion 75 and the supporting tooth portion 77 are engaged again.

  In the support mechanism 50 of the embodiment, each holding tooth portion 75 of the holding portion 53 and each support tooth portion 77 of the stopper portion 54 are each formed in an involute tooth profile with a pressure angle α = 20 °. Therefore, as shown in FIG. 7, when a force that rotates downward is applied to the armrest body 10, the stress F generated at the pitch point P of both the tooth portions 75 and 77 is directed in the normal direction with respect to the pressure angle α. Act. That is, as apparent from FIG. 7, the stress F generated at the pitch point P is the same as the “shear direction” in the tooth thickness direction of the support tooth portion 77 and the holding tooth portion 75, and the pressure angle α Acts in different directions with equal angular differences. Therefore, when the armrest body 10 is subjected to a downward rotating force, chipping of the holding tooth portion 75 and the support tooth portion 77 is difficult to occur.

  As shown in FIG. 7, the stress F acting in the normal direction with respect to the pressure angle α at the pitch point P between the holding tooth portion 75 and the support tooth portion 77 is variable from the pitch point P to the variable support portion 52. Is divided into a first component force F1 in the direction of the rotation center C2 and a second component force F2 in a direction orthogonal to the first component force F1. Among these, the second component force F2 acts in a direction in which the degree of meshing between the support tooth portion 77 of the stopper portion 54 and the holding tooth portion 75 of the holding portion 53 increases. Therefore, each of the holding tooth portion 75 of the holding portion 53 and the support tooth portion 77 of the stopper portion 54 is formed in an involute tooth profile with a pressure angle α = 20 °, so that the armrest body 10 is rotated downward. When force is applied, the meshing degree of both the tooth portions 75 and 77 is strengthened, and the support tooth portion 77 becomes difficult to be detached from the holding tooth portion 75, so that the posture of the armrest body 10 can be reliably maintained.

  A projecting piece 80 as a first switching portion is formed integrally with the holding portion 53 at the rear end of the holding portion 53 (in the embodiment, the lower end of the holding portion 53) in the upward rotation direction of the armrest body 10. . As shown in FIG. 10A, the projecting piece 80 abuts against the lowermost support tooth portion 77 of the stopper portion 54 in the holding posture of the variable support portion 52 when the armrest body 10 is rotated upward. The projecting dimension is set so that the supporting portion 52 can be pushed to a position exceeding the switching position described above. Therefore, when the protruding piece 80 comes into contact with the stopper portion 54 in the middle of rotating the armrest body 10 upward, as shown in FIG. 10B, the variable support portion 52 is brought into a retracted posture by the urging force of the torsion spring TS. Displaced and held in the retracted posture. In the state where the stopper portion 54 is held in the retracted position, the armrest body 10 cannot mesh with the support tooth portion 77 of the stopper portion 54 and the holding tooth portion 75 of the holding portion 53, and the upper rotation and the lower rotation are prevented. It becomes free (FIG. 10 (b), FIG. 8 (a)).

  Further, the contact piece 72 that extends on the displacement locus of the protruding piece 80 in the retracted posture of the variable support portion 52 is provided below the variable support portion 52. As shown in FIG. 8A, the contact piece 72 displaces the variable support portion 52 in the retracted position to the holding position by the protruding piece 80 coming into contact with the upper side when the armrest body 10 rotates downward. Is for. Therefore, when the protruding piece 80 comes into contact with the contact piece 72 while the armrest body 10 is rotated downward, the stopper portion 54 is held by the biasing force of the torsion spring TS as shown in FIG. And is held in the holding posture.

  As shown in FIG. 2, the support mechanism 50 of the embodiment configured as described above has a support boss portion 68 of the sub bracket 56 in the fixed support portion 51 when disposed in the housing portion 10 </ b> A of the armrest body 10. However, the recessed portion 25 of the main body member 20 comes into contact with the connecting plate portion 59 of the main bracket 55 in the fixed support portion 51 while fitting into the circular opening portion 43 of the cover member 40. Thereby, the support mechanism 50 can support the armrest main body 10 appropriately without rattling.

(Operation of Example)
Next, the operation of the armrest AR of the embodiment configured as described above will be described with reference to FIGS. When the armrest AR is in the non-use position shown in FIG. 11, the variable support portion 52 is held in the retracted posture by the urging force of the torsion spring TS.

  When pulling out the armrest AR to the use position, as shown in FIG. 8A, the armrest main body 10 rotates downward, and the protruding piece 80 contacts the contact piece 72 from above. As a result, as shown in FIG. 8B, the variable support portion 52 rotates in the clockwise direction in FIG. 8 about the rotation center C2, and the variable support portion 52 is displaced from the retracted posture to the holding posture. Accordingly, the support tooth portion 77 of the stopper portion 54 is guided by the mutual tooth shape while being in contact with the holding tooth portion 75 of the holding portion 53, and the variable support portion 52 is displaced to the holding posture. Thereby, the support tooth part 77 and the holding tooth part 75 come to mesh with each other, and the armrest body 10 is held in a posture. In this state, the armrest AR is held at the lowest position in a substantially horizontal posture, and the support tooth portion 77 of the stopper portion 54 is engaged with the uppermost portion in the engagement region G of the holding portion 53. In addition, since the gear head portion 74 of the variable support portion 52 is aligned with the support receiving portion 66 formed on the main bracket 55 of the fixed support portion 51 from above, when a force is applied to the armrest AR from above, the load due to this is applied to the gear head. It is received by the fixed support portion 51 via the portion 74.

  When the tip end side of the armrest AR is appropriately lifted upward from the state shown in FIG. 8B, as shown in FIG. 9A, the support tooth portion 77 of the stopper portion 54 and the holding tooth portion 75 of the holding portion 53 are separated. Under the contact, the variable support portion 52 is displaced from the holding posture to a posture in which the meshing of both the tooth portions 75 and 77 is released. Thereby, the meshing of the support tooth portion 77 and the holding tooth portion 75 is released, and the upward rotation of the armrest body 10 is allowed. Then, in a state where the distal end side of the armrest AR is appropriately moved upward, when the armrest AR is slightly returned downward, as shown in FIG. 9 (b), the distal ends of the support tooth portion 77 and the holding tooth portion 75 are aligned. The contact is released, the variable support portion 52 is displaced to the holding posture, and both the tooth portions 77 and 75 are engaged again. Accordingly, the armrest AR is held in an inclined state in which the front end side is higher than the rear end side.

  In the support mechanism 50 of the embodiment, as described above, the meshing position of the support tooth portion 77 of the stopper portion 54 with respect to the retaining tooth portion 75 of the retaining portion 53 can be changed in nine stages in the meshing region G of the retaining portion 53. . Therefore, the angle of the armrest AR can be adjusted in nine stages, and the armrest AR can be adjusted to an angle preferred by the passenger using the seat S.

  In the support mechanism 50 of the embodiment, each of the holding tooth portions 75 of the holding portion 53 and each of the support tooth portions 77 of the stopper portion 54 are formed in an involute tooth profile with a pressure angle α = 20 °. Therefore, when a force to rotate downward is applied to the armrest body 10, the stress F generated at the pitch point P of both tooth portions 75 and 77 is the same as the tooth thickness direction at the tooth base of both tooth portions 75 and 77. The “shear direction” acts in different directions with an angle difference equivalent to the pressure angle α. Therefore, when a force for rotating downward is applied to the armrest body 10, the holding tooth portion 75 and the support tooth portion 77 are unlikely to be chipped, and the support mechanism 50 can be prevented from being damaged.

  When returning the armrest AR from the use position in any of the nine stages described above to the non-use position, the armrest body 10 rotates upward as shown in FIG. At this time, the support tooth portion 77 is guided by the tooth shape while being in contact with the holding tooth portion 75, and the variable support portion 52 is displaced from the holding posture to a posture capable of releasing the engagement of both the tooth portions 75 and 77. Thus, the meshing between the support tooth portion 77 and the holding tooth portion 75 is released, and the upward rotation of the armrest body 10 is allowed. Then, while the armrest body 10 rotates upward, the protruding piece 80 formed on the armrest body 10 comes into contact with the lowermost support tooth portion 77 of the stopper portion 54 from below. Accordingly, as shown in FIG. 10B, the variable support portion 52 is displaced to the retracted posture and is held in the retracted posture, and the support tooth portion 77 of the stopper portion 54 and the holding tooth portion 75 of the holding portion 53 Cannot mesh. Accordingly, the armrest body 10 is allowed to rotate upward, and the armrest AR can be returned to the non-use position.

(Example of change)
The present invention is not limited to the above-described embodiments, and the following configurations can also be employed.
(1) The armrest AR of the embodiment is described as being attached to the left side portion of the seat back S1 in the seat S. However, the armrest AR is attached to the right side portion of the seat back S1 or the front portion of the seat back S1. It may be a thing.
(2) The holding tooth portion 75 of the holding portion 53 and the support tooth portion 77 of the stopper portion 54 are exemplified as involute teeth having a pressure angle α = 20 °, but the pressure angle α is 20 °. There is no limitation as long as it is an acute angle. The tooth profile is not limited to the involute tooth profile, and may be a cycloid tooth profile or a trapezoidal tooth profile.
(3) In the embodiment, the configuration in which the holding portion 53 and the stopper portion 54 are disposed on the distal end side from the rotation center C1 on the basis of the rotation center C1 of the armrest body 10 is illustrated. The arrangement position of 54 is not limited to this. That is, the holding portion 53 and the stopper portion 54 may be disposed rearward from the rotation center C1 in the use state of the armrest body 10, or may be disposed below the rotation center C1, or the rotation center C1. You may arrange | position above.

It is a side view which shows the armrest which concerns on an Example in the state which transparently displayed the skin material and the cushion material. It is the II-II sectional view taken on the line of FIG. It is the III-III sectional view taken on the line of FIG. It is a disassembled perspective view which shows the main body member and cover member which comprise an armrest main body, and a support mechanism. It is a side view which shows the support mechanism arrange | positioned by the armrest main body in the state which removed the cover member. It is explanatory drawing which showed that the variable support part which comprises a support mechanism displaces to a holding | maintenance attitude | position and a retracted attitude | position. It is explanatory drawing which shows the positional relationship of the rotation center of an armrest main body, and the rotation center of a variable support part, and the stress which acts on the pitch point (meshing position) of a holding tooth part and a support tooth part, and the component of the stress is there. It is explanatory drawing which partially shows the state which rotates an armrest downward, (a) shows the state which the protrusion piece provided in the armrest main body contact | abuts the contact piece provided in the variable support part, (b) is The state in which the armrest body is held by the displacement support portion being displaced to the holding posture and the support tooth portion of the stopper portion meshing with the holding tooth portion of the holding portion is shown. It is explanatory drawing which shows partially the state which rotates an armrest suitably upwards, Comprising: (a) is the position of a support tooth part of a stopper part, and a holding part because a variable support part is displaced appropriately from a holding posture to a retreat posture side. The engagement with the holding tooth part is released, and the upward rotation of the armrest body is permitted, and (b) shows that the variable support part is displaced to the holding posture by slightly returning the armrest body, and the stopper part A state where the support tooth portion is engaged with the holding tooth portion of the holding portion and the armrest body is held is shown. It is explanatory drawing which shows the state which rotates an armrest partially, Comprising: (a) shows the state which the protrusion piece provided in the armrest main body contact | abutted the support tooth part of the stopper part, (b) shows armrest While the main body is rotated upward, the variable support portion is displaced to the retracted posture. It is a side view which shows the armrest attached to the seat back of the seat.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Armrest main body, 50 Support mechanism, 51 Fixed support part, 52 Variable support part 53 Holding part, 54 Stopper part, 66 Support receiving part (regulation part), 72 Contact piece (2nd switching part)
75 holding tooth part, 77 supporting tooth part, 80 protruding piece (first switching part)
C1 center of rotation (of armrest body 10), C2 center of rotation (of variable support 52)
P pitch point, L line, S sheet, TS torsion spring (biasing member), α pressure angle

Claims (5)

An armrest having a support mechanism that supports the armrest body so as to be rotatable in the vertical direction with respect to the seat,
The support mechanism is
A fixed support portion that is provided so as not to rotate with respect to the seat and supports the armrest body rotatably;
A variable support portion disposed on the fixed support portion and displaceable in a rotational direction of the armrest body;
A holding portion having a plurality of holding teeth arranged in an internal gear shape centered on the rotation center, the armrest main body facing the rotation center side of the armrest main body;
Provided on the peripheral surface of the variable support portion, and in the holding posture of the variable support portion, in line with the external gear shape centering on the rotation center corresponding to the internal gear formed by the holding tooth portion, A stopper portion having a plurality of support tooth portions capable of meshing;
A restriction portion provided on the fixed support portion and restricting displacement of the variable support portion in the holding posture in the downward rotation direction of the armrest body;
When the armrest body is rotated downward, the support tooth portion is guided by the tooth shape while being in contact with the holding tooth portion, and the armrest body is rotated in the downward direction so that the variable support portion is in the holding posture. When the armrest body is rotated upward, the support tooth portion is guided by the tooth shape of each other while being in contact with the holding tooth portion, so that the meshing of both the tooth portions can be released. An armrest that is configured to be displaced in the upward rotation direction of the armrest main body so as to have a proper posture. The holding portion and the stopper portion of the variable support portion in the holding posture are in a relationship in which the holding tooth portion and the supporting tooth portion mesh on the same reference circle,
The holding tooth part and the support tooth part are formed in a tooth profile that tapers from a tooth base toward a tooth tip so that a pressure angle at a pitch point between the holding tooth part and the support tooth part becomes an acute angle. The armrest according to 1. The variable support portion is disposed rotatably with respect to the fixed support portion,
The rotation center of the variable support portion is configured to be positioned so as to be separated from the line connecting the rotation center of the armrest body and the pitch point of both tooth portions in a direction in which the armrest body rotates downward. Armrest described.   The armrest according to any one of claims 1 to 3, wherein the support mechanism includes a biasing member that biases the variable support portion toward the holding posture. The support mechanism is provided at a rear end of the holding portion in the upward rotation direction of the armrest body, and abuts on the stopper portion when the armrest body rotates upward, so that the support tooth portion and the holding tooth portion cannot be engaged with each other. A first switching part for displacing the variable support part to a retreating position;
Provided in the variable support portion, the variable support portion is provided so as to extend on a displacement locus of the first switching portion in the retracted posture, and the first switching portion abuts when the armrest body is rotated downward. The armrest as described in any one of Claims 1-4 provided with the 2nd switching part which displaces this variable support part to the said holding | maintenance attitude | position.

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