JPH11113665A - Knuckle structure for seat - Google Patents

Abstract

PROBLEM TO BE SOLVED: To give good appearance, make a seat comfortable to sit on, and make it more difficult for force in the direction of torsion to act on a seat back. SOLUTION: A knuckle structure for a seat comprises a pair of widthwise brackets 3 fixed to both sides of the rear part of a seat bottom, a connection rod 4 extending between the brackets 3 so as to be freely turnable around its axis, a pair of widthwise knuckle plates 5 fixed to both sides of the lower part of a seat back so as to correspond to the brackets 3 and supported by pivots so as to be freely turnable around the connection rod 4, a spiral spring 6 for urging the seat back so as to incline it forward, and a lock mechanism 7 for locking the seat back into an arbitrary position against the urging force of the spiral spring 6 by operating an operation lever 8 and for releasing the lock. The spiral spring 6 is provided on the opposite sides of the pair of knuckle plates 5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a seat knuckle structure for connecting a seat bottom as a seat to a seat and a seat back as a backrest provided at a rear end of the seat bottom so as to be capable of changing an inclination angle. It is about.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 8, there has been known a seat 1 which is configured to be able to change its attitude between an inclined attitude inclined backward and a tilted attitude inclined forward. The seat 1 includes a two-seat seat bottom 11 and a pair of widthwise seat backs 12 erected at the rear edge of the seat bottom 11. At the rear end of the seat bottom 11, a total of two pairs of brackets 300 are provided in a pair in the width direction for each seat back 12, and the horizontal shafts 400 are bridged between the brackets 300, respectively. Is provided with a knuckle plate 500 that is rotatable about a horizontal axis 400, whereby the seat back 12 is rotated about the horizontal axis 400, and has a rearwardly inclined posture inclined rearward and a forwardly inclined posture inclined forwardly. The posture can be changed between.

[0003] Such a seat 1 includes a seat back 1
A spiral spring 600 for urging the seat back 2 in the forward leaning posture is provided, and the posture of the seat back 12 at an arbitrary rotation position between the forward leaning posture and the backward leaning posture is locked or locked. A lock mechanism for releasing is provided. Locking and unlocking are performed by operating an operation lever 800 projecting outward from the knuckle plate 500.

[0004] Therefore, the occupant of the seat 1 operates the operation lever 800 in one direction to release the locked state, and attempts to lean forward with the urging force of the spiral spring 600.
By selecting a desired inclination angle while holding the back of the seat back 2, and then operating the operation lever 800 in the other direction, the rotation of the seat back 12 is locked, whereby the selected inclination posture of the seat back 12 is maintained. Will be.

[0005]

Since the conventional spiral spring 600 is provided on the outer surface side of the knuckle plate 500, the installation space for the spiral spring 600 must be secured on the side of the seat 1. However, the width dimension of the seat 1 (particularly, the seat back 12) is reduced by that amount, and the sitting comfort is deteriorated, and the protruding spiral spring 600 has a problem that the external appearance is unsightly.

In order to solve such a problem, for example, in the case of a seat 1 for two persons, an adjacent seat back 1
The knuckle plate 500 is gouged and the spiral spring 60
When the space 601 for accommodating the knuckle plate 500 is secured and the portion above the knuckle plate 500 is extended, the overhang portion 120 may be formed. By doing so, the portion of the seat back 12 corresponding to the flank of the occupant is narrow, but the portion of the back is wide, and there is no problem in terms of comfort.

However, if a space 601 for the spiral spring 600 is formed below the adjacent seat back 12, this portion becomes transparent so that the viewability is not eliminated and the overhang portion 120 of the seat back 12 has When the weight of the occupant is added, a force in the torsional direction acts on the seat back 12, which raises a new problem that the seat back 12 is easily damaged. In order to solve this, the frame of the seat back 12 must be made stronger than before, which raises a new problem that the cost is increased.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and has a good appearance, good sitting comfort, and a seat knuckle in which a torsional force is less likely to act on the seat back. It is intended to provide structure.

[0009]

A knuckle structure for a seat according to a first aspect of the present invention comprises a seat bottom serving as a seat, and a backrest that is provided at a rear end of the seat bottom so as to be capable of changing an inclination angle. A knuckle structure of the seat for connecting the seat back and a pair of width-wise brackets fixed to the rear side surfaces of the seat bottom, and is inserted between each bracket so as to be rotatable around its own axis. A connecting rod, and a pair of flat knuckle plates in the width direction, which are fixed to the lower side surfaces of the seat back corresponding to the brackets, respectively, and are rotatably supported around the connecting rod. A spiral spring for urging the seat back to incline forward, and locking an arbitrary posture of the seat back against the urging force of the spiral spring by operating an operation lever. Moni, and a locking mechanism provided for releasing the lock, the spiral spring is characterized in that provided on the opposite side of the pair of knuckle plates.

According to the knuckle structure of the seat, when the operating lever is operated in one direction, the lock mechanism locks the knuckle plate and the bracket with each other, thereby restricting the rotation of the bracket about the connecting axis. The set seat back posture is fixed.
By operating the operation lever in the other direction in this state, the lock by the lock mechanism is released, and the seat back is urged by the urging force of the spiral spring to incline forward around the connection axis. By returning the operation lever to the original direction at the time when the vehicle reaches the desired inclination angle, the seat back is locked by the lock mechanism at the desired inclination angle and the inclination angle is maintained.

Since the spiral spring is provided on the opposite surface side of the pair of knuckle plates, the spiral spring protrudes outwardly from the side surface of the seat as compared with the conventional spiral spring provided on the outer surface side of the knuckle plate. Occupation of space due to
The unsightly appearance is eliminated, and the width dimension of the sheet can be increased by the absence of the spiral spring, and the appearance of the sheet can be improved.

Further, there is no need to provide an overhang-like overhanging portion above the space in which the spiral spring is provided, and the seat back is structurally balanced. By the way, if there is an overhang-like overhanging portion as in the past, a twisting force acts on the seat back when the weight of the occupant is added to the overhanging portion,
This causes a disadvantage that the seat back is easily damaged, but such a disadvantage does not occur in the present invention.

According to a second aspect of the present invention, there is provided the seat knuckle structure according to the first aspect, wherein the spiral spring is a spiral spring mounted around the connecting rod. Is what you do.

According to the knuckle structure of the seat, the use of the spiral spring makes it possible to widen the range of rotation of the knuckle plate around the connecting rod and reduce the space occupied by the spiral spring.

According to a second aspect of the present invention, there is provided the seat knuckle structure according to the first aspect, wherein the connecting rod is supported by the bracket so as to be rotatable around its own axis. The knuckle plate is integrally connected to the rod, and the spiral spring has an inner end fixed to the connecting rod, an outer end fixed to the bracket, and the lock mechanism has a tooth surface. And a toothless gear fixed to the bracket so as to be concentric with the connecting rod, and supported by the knuckle plate so as to be rotatable around a support shaft, and biasing means for the teeth of the toothless gear. A lock piece having teeth that always mesh with the urging force, an operating rod connected to the operating lever concentric with the connecting rod and rotatable relative to the connecting rod, and fixed to the operating rod And an operating piece for operating the lock piece by rotating the operating rod in a predetermined direction to release the constant mesh between the toothless gear and the lock piece. The spiral spring is interposed between the spiral spring and the knuckle plate.

According to the knuckle structure of the seat, the connecting rod, the inner end of which is fixed by the biasing force of the spiral spring whose outer end is fixed to the bracket, exerts a force in the direction of rotating about the axis. As a result, the seat back can always be turned forward.

The turning operation of the operating lever is transmitted to the lock piece via the connecting rod and the operating piece, and the locked state in which the teeth of the lock piece mesh with the teeth of the toothless gear according to the operating direction of the operating lever. And a lock release state in which the engagement between the teeth of the lock piece and the teeth of the toothless gear is released.

As described above, since the locked state is maintained by the engagement of the teeth of the lock piece and the teeth of the toothless gear, the circumferential range of the tooth surface of the toothless gear can be widened. Whatever the range of the angle of the seat back is set, the toothless gear can cope with such a range, and the locking mechanism becomes versatile. Also, due to the engagement of each of the plurality of teeth of the lock piece and the toothless gear,
The maintained state of the set seat back posture is ensured.

Further, since the spiral spring is provided between the operating piece and the knuckle plate, the spiral spring is sandwiched between the operating piece and the knuckle plate, and the mounted state of the spiral spring is stabilized.

[0020]

FIG. 1 is a perspective view showing an embodiment of a seat to which a knuckle structure according to the present invention is applied. In FIG. 1, the XX direction is referred to as a width direction, the YY direction is referred to as a front-back direction, and in particular, the −X direction is referred to as left, the + X direction is referred to as right, the −Y direction is referred to as front, and the + Y direction is referred to as rear. As shown in this figure, a seat 1 is provided with a seat bottom 11 as a seating seat provided on a floor F via a slider 13 and a bottom frame 14, and a backrest erected on a rear edge of the seat bottom 11. And a seat back 12. In the present embodiment, the seat 1 is a two-seat one, and the seat bottom 11 is a wide one-piece one for two people.
Are provided for a single person in a pair in the width direction.

The slider 13 includes a lower rail fixed to the floor F, and an upper rail guided by the lower rail to move back and forth.
The seat bottom 11 can be moved back and forth by fixing the seat 4 to the upper rail.

The seat back 12 has a back frame 15 as a skeleton.
The knuckle structure 2 according to the present invention is interposed between the bottom frame 5 and the bottom frame 14 so that the seat back 12
Can change its posture between an inclined posture inclined backward by a predetermined angle and an upright posture standing upright on the seat bottom 11.

FIG. 2 is an exploded perspective view showing an embodiment of the knuckle structure 2 according to the present invention, and FIG. 3 is an assembled perspective view thereof. FIG. 4 is a sectional view taken along line A of FIG. 3, and FIG. 5 is a sectional view taken along line BB of FIG. 2 and 3, the XX direction is referred to as the width direction, the YY direction is referred to as the front-back direction, and particularly the -X direction is leftward, the + X direction is rightward, and -Y.
The direction is referred to as front, and the + Y direction is referred to as rear. 2 and 3 show the knuckle structure 2 provided on the right one of the pair of seatbacks 12 in the width direction shown in FIG.

As shown in these figures, the knuckle structure 2
Are a pair of brackets 3 in the width direction fixed to the bottom frame 14, a connecting rod 4 bridged between the pair of brackets 3, and a pair of width-directional shafts rotatably supported around the connecting rod 4. A knuckle plate 5, a spiral spring 6 for urging the knuckle plate 5 counterclockwise around the connecting rod 4, and locking an arbitrary posture of the seat back 12 against the urging force of the spiral spring 6; A lock mechanism 7 for releasing this lock is provided.

The bracket 3 is formed into a predetermined flat plate shape by pressing a metal plate, and a recess 31 is formed in the lower front edge of the bracket 3 so as to fit into the bottom frame 14. The upper edge portion has a triangular shaft support portion 32 projecting upward. The shaft support portion 32 is provided with a shaft support hole 33 into which the distal end of the connecting rod 4 is fitted in a sliding contact state. And concave groove 3
The bracket 3 is fixed to the bottom frame 14 by being bolted in a state where 1 is fitted over the upper portion of the bottom frame 14.

The connecting rod 4 is connected to a short large-diameter rod 41 integrally connected to the left knuckle plate 5 and a large-diameter rod concentrically connected to the large-diameter rod 41 so as to be relatively rotatable around an axis. An operation rod 42 having a smaller diameter than the diameter rod 41 is provided. The large-diameter rod 41 includes a large-diameter portion 41a formed on the right side, and a small-diameter portion 41b concentrically projecting leftward from the left end surface of the large-diameter portion 41a. Is fixed to the knuckle plate 5 by welding while penetrating a proper portion below the knuckle plate 5, while the small diameter portion 41 b is fitted in the shaft support hole 33 of the bracket 3 in a sliding contact state.

The large-diameter rod 41 has a large-diameter portion 41.
A connection hole 41c drilled so that the right end of the operation rod 42 is fitted in the axial center portion of the right end face of FIG.
(FIG. 5) and a locking groove 41d traversing the right end face in the radial direction.
(FIG. 5). The locking groove 41d is for fitting and locking the center end 61 of the spiral spring 6.

The right knuckle plate 5 has an operating rod 4 at a portion concentrically opposed to the large diameter rod 41.
A support hole 5a is formed in the right knuckle plate 5, and a shaft support hole 33a of the same diameter facing the support hole 5a is formed in the right knuckle plate 5.
The small-diameter portion 41b of the large-diameter rod 41 is fitted into the left shaft support hole 33, and the right end of the operation rod 42 is inserted into the support hole 5a.
The right and left knuckle plates 5 are fitted between the right and left shaft support holes 33 a so as to be mounted between the pair of left and right brackets 3 while being rotatably supported around the connecting rod 4. .

The knuckle plate 5 is formed in a vertically long elliptical box shape by press-forming a metal plate. The knuckle plate 5 has a flat knuckle body 51 and an outer side (left side) from the outer peripheral edge. The knuckle plate 5 is provided with an annular projecting edge 52 projecting toward the left side and the right knuckle plate 5 toward the right side.

The left knuckle main body 51 is provided with an arc hole 53 centered on the axis of the large-diameter rod 41 along the lower edge, while the knuckle main body 51 is formed in the shaft support portion 32 of the bracket 3. The stopper pin 34 (FIG. 5) is penetrated from the left side, and the tip of the stopper pin 34 fits into the arc hole 53 so that the rotation range of the knuckle plate 5 around the connecting rod 4 is set.

The arc hole 53 is positioned at an arc so that the knuckle plate 5 can rotate around the connecting rod 4 between the angle at which the seat back 12 is inclined and the angle at which the seat back 12 is upright. And the arc length are set, and the stopper pin 34 abuts on the edge of the arc hole 53 so that the stopper pin 34 does not incline in any of the forward and reverse directions beyond a predetermined inclination angle with respect to the vertical line.

The spiral spring 6 is provided with a bent end portion 62 formed by being bent outward at the tip end thereof, and the central end 61 of the spiral spring 6 in the wound state is connected to the large-diameter rod 41. Of the stopper pin 34 penetrating through the arc hole 53, and a biasing force in the rewind direction is generated in the spiral spring 6, whereby the spiral spring 6 rotates the knuckle plate 5 counterclockwise around the large diameter rod 41.

The left knuckle main body 51 has a first support shaft 54 projecting leftward from a substantially central portion in the up-down direction and a left side of a portion closer to the rear. A second support shaft 55 protrudes leftward in the vicinity of the protruding edge 52 at a position forward of the first support shaft 54. A second arc hole 5 centered on the first support shaft 54 is provided at a substantially intermediate position between the first support shaft 54 and the large-diameter rod 41.
6 are drilled.

Further, a pair of upper and lower fastening holes 57 are formed in the upper portion of the left and right back frames 51 on a straight line extending in the radial direction from the axis of the large diameter rod 41. The seat back 12 is attached to each knuckle plate 5 by being inserted into a predetermined hole of the back frame 15 and fastened with a nut N.

The lock mechanism 7 includes the left bracket 3
Gear 71 fixed on the right side of the shaft concentrically with the shaft support hole 33
And a lock piece 72 having teeth that mesh with the teeth of the toothless gear 71, and a pressing piece 73 that holds the lock piece 72 in the direction of the toothless gear 71 to ensure the meshing state between the two.
And an operation plate 74 for causing the lock piece 72 to engage and disengage with the toothless gear 71, and for pressing and releasing the press piece to and from the lock piece 72, and an operation plate 74. Operation piece 75 for operating
It is comprised including.

The toothless gear 71 has a shaft support hole 71 having the same diameter as the shaft support hole 33 of the bracket 3 at the center.
a and a gear-side tooth surface 71b having a plurality of teeth formed on a part of the outer peripheral surface. The toothless gear 71 is fixed to the bracket 3 by rivets 35 on both sides of the stopper pin 34 in the front-rear direction. The stopper pin 34 is provided with a toothless gear 71.
, And the tip protrudes from the right side of the toothless gear 71 to the outside.

The lock piece 72 is formed to be long in the front-rear direction. The second end of the lock piece 72 is
A locking hole 72a is formed in the support shaft 55 so as to be fitted in sliding contact with the support shaft 55, and the gear-side tooth surface 7 is formed on the rear lower edge.
Lock one side tooth surface 72b having a plurality of teeth corresponding to 1b
Are formed. Then, with the locking hole 72a fitted on the second support shaft 55, the lock piece 72 is moved to the second support shaft 55.
By rotating the lock knuckle plate 5 in the clockwise direction, the lock one-side tooth surface 72b meshes with the gear-side tooth surface 71b, thereby preventing the knuckle plate 5 from rotating around the connecting rod 4 and supporting the lock member 72 in the second support. By rotating counterclockwise around the shaft 55, the meshing is released,
Thus, the knuckle plate 5 is released from being prevented from rotating around the connecting rod 4.

The operation plate 74 is formed of a plate-like body having a fan shape spreading downward, and the first support shaft 5
A support hole 74a is formed in the outer peripheral surface of the support hole 4 in a sliding contact state, and a third circular hole 74b centered on the support hole 74a is formed in the lower edge. Further, the knuckle main body 51 is further rearwardly located below the third arc hole 74b.
Connection pin 74c (FIG. 5) loosely fitted in the second arc hole 56 of FIG.
Is protruding.

A coil spring (biasing means) 76 is stretched between the top of the operation plate 74 and the left protruding edge 52 of the knuckle plate 5. The operation plate 74 has its support hole 74
a is received in the counterclockwise direction around the first support shaft 54 in a state of being fitted into the first support shaft 54, whereby the connection pin 74 c abuts on the rear end edge of the second arc hole 56. Thus, the rotation about the first support shaft 54 is restricted.

On the other hand, on the rear right surface of the lock piece 72,
An operation pin 72c (FIG. 5) projecting rightward is provided. The operation pin 72c is connected to the third arc hole 7
The projecting position is set so as to be loosely fitted to 4b. Then, the operation plate 74 is pressed against the urging force of the coil spring 76.
Is rotated clockwise about the first support shaft 54, so that the rear end edge of the third arc hole 74b abuts on the operation pin 72c and lifts it upward. Rotating in the counterclockwise direction about the shaft 55, the engagement state of the lock one side tooth surface 72b with the gear side tooth surface 71b is released.

The holding piece 73 is composed of a holding plate body 73a having a circular shape, and a rectangular stopper 73b protruding below the holding plate body 73a. And
At the center of the holding plate body 73a, there is formed a mounting hole 73c which is fitted to the first support shaft 54 in a sliding state, and the stopper 73b projects rightward on the right side thereof. The provided guided pin 73d (FIG. 5) is projected, while the operation plate 74 has a support hole 74a.
A guide hole 74d corresponding to the guided pin 73d is formed in a substantially intermediate portion between the guide pin 73d and the third arc hole 74b.

By fitting the mounting hole 73c outside the first support shaft 54 on which the operation plate 74 is already mounted, the guided pin 73d is fitted into the guide hole 74d.
Thus, the operation plate 74 and the holding piece 73 rotate together around the first support shaft 54. And
When the stopper portion 73b is positioned below, the lower end edge of the presser piece 73 presses the rear upper edge of the lock piece 72 so that the gear-side tooth surface 71b of the lock-side tooth surface 72b.
The dimensions are set so that the meshing state with respect to is reliably performed.

An inverted triangular cover 77 is attached to a lower portion of the knuckle plate 5. The cover 77 has a lock piece 72, a holding piece 73 and an operation plate 7.
By covering the knuckle body 51, the mounting state of the knuckle body 51 is stabilized, and the movable part of the lock mechanism 7 is hidden from the outside.

That is, a small diameter caulking hole 77 a corresponding to the first support shaft 54 and the second support shaft 55 is formed in the cover body 77 and the large diameter rod 41 is formed.
A large diameter caulking hole 77b corresponding to the small diameter portion 41b of the first support shaft 5 is formed in the caulking holes 77a and 77b.
4. Second support shaft 55 and small diameter portion 41 of large diameter rod 41
These tips are swaged with b fitted
Thereby, the cover body 77 is attached to the knuckle plate 5.

The lower end of the cover 77 has a tongue 77
c protrudes downward. The length of the tongue piece 77c is set so as to be able to press the head of the stopper pin 34. With this, as shown in FIG. 3, the left bracket is attached to the knuckle plate 5 with the cover body 77 attached. 3. Stopper pin 34 fitted in the predetermined hole
Is prevented from falling off.

The operation piece 75 has an operation piece main body 75a whose base end is fixed to the operation rod 42 and is elongated in the radial direction.
And an operation claw 75b parallel to an operation piece main body 75a formed by bending its tip into an L-shape.
The operation claw 75b is provided with an outer fitting hole 75c which is fitted to the connection pin 74c of the operation plate 74 in a sliding state with the left end of the operation rod 42 fitted in the connection hole 41c of the large diameter rod 41. Has been established. The operating piece 75 is shaped so that a spring accommodating space 75d for accommodating the spiral spring 6 is formed on the left side of the operating piece main body 75a in a state where the outer fitting hole 75c is externally fitted to the connection pin 74c. I have. By providing such an operation piece 75, the spiral spring 6 can be disposed inside the knuckle plate 5.

At the right end of the operation rod 42, an operation lever 8 made of a flat plate is provided. This operation lever 8
Has a square hole 81 formed on the base end side, while a prism 42a corresponding to the square hole 81 is provided at the right end of the operation rod 42, and the square hole 81 is fitted to the prism 42a. Screw 42 is screwed into the end face of the prism 42a
The operation lever 8 is mounted on the operation rod 42 by screwing and fastening b. By operating the operation lever 8, the operation rod 42 is operated.
Rotates forward and backward about its own axis, whereby the operation of the lock mechanism 7 locks or releases the inclined posture and the upright posture of the seat back 12.

FIGS. 6A and 6B are explanatory views for explaining the operation of the lock mechanism 7. FIG. 6A shows a state where the knuckle plate 5 is locked so as not to rotate, and FIG. 6B shows a state where the lock is released. (C) shows a state where the knuckle plate 5 is tilted rearward.

First, in the state shown in FIG. 6A, the operating plate 74 receives an urging force in the counterclockwise direction around the first support shaft 54 by the urging force of the coil spring 76, and thereby the guide hole 74d is Pressing piece 73 by moving to the right
The guided pin 73d rotates counterclockwise around the first support shaft 54, and the stopper 73b presses the upper right end of the lock piece 72. In this state, the lock one side tooth surface 72 of the lock piece 72 supported by the second support shaft 55
b is the gear-side tooth surface 7 of the toothless gear 71 integrated with the bracket 3
1b, whereby the knuckle plate 5 integrated with the lock piece 72 is restricted from rotating around the connecting rod 4, and the seat back 12 is in an upright posture.

The connection pin 74c is connected to the operation plate 7
4 has been moved to the right in the second arc hole 56 by the counterclockwise rotation about the first support shaft 54,
As a result of this movement, the operating piece 75 whose outer fitting hole 75c is fitted around the connection pin 74c rotates together with the operating rod 42 around the operating rod 42, whereby the operating lever 8 provided at the distal end of the operating rod 42 becomes It is in a state where the posture is set to a lock posture that is inclined obliquely upward toward the front.

In this state, as shown in FIG.
When a lock release operation of rotating the operation lever 8 counterclockwise around the operation rod 42 is performed, the operation piece 75 rotates counterclockwise around the operation rod 42, and the outer fitting hole 7
The operation plate 74 is rotated clockwise around the first support shaft 54 by the leftward movement of the connection pin 74c fitted in the 5c, so that the first support shaft 54 of the pressing piece 73 that rotates together with the operation plate 74. The rotation in the clockwise direction releases the pressing of the lock portion 72 by the stopper portion 73b, and the operation pin 72c
4 by the right edge of the third arc hole 74,
As a result, the gear-side tooth surface 71b of the lock one-side tooth surface 72b
Is released, and the seat back 12 becomes rotatable around the connecting rod 4.

In this state, the knuckle plate 5 receives a force in the direction of leaning forward around the connecting rod 4 by the urging force of the spiral spring 6, thereby causing the seat back 12.
Is in an upright posture. Therefore, when the occupant of the seat 1 operates the operation lever 8 downward and strongly presses the back against the seat back 12, as shown in FIG. The seat back 12 rotates clockwise around the connecting rod 4 against the force. When the user releases the operating lever 8 with the seat back 12 at the desired inclination angle, the operating lever 8 returns to the original locked position by the urging force of the coil spring 76 and the first support of the operating plate 74. The counterclockwise rotation about the shaft 54 causes the stopper portion 73b of the pressing piece 73 to press the upper right end of the lock piece 72, whereby the lock single side tooth surface 72b meshes with the gear side tooth surface 71b. The desired tilt angle is locked.

FIG. 7 is a diagram for explaining the operation of the present invention.
FIG. 3 is an explanatory diagram of the seat 1 to which the lock mechanism 7 is applied, as viewed from the front. In the present invention, since the spiral spring 6 is provided inside the knuckle plate 5 as shown in FIG. 7, when the spiral spring 600 is provided outside the knuckle 500 as in the related art (see FIG. 8). In comparison, the spiral spring 60
There is no need to provide the space 601 for zero, the unsightly appearance of the seat 1 can be eliminated, and the width dimension of the seat back 12 can be increased by the absence of the spiral spring 6 outside.

Further, there is no need to provide an overhang portion 120 (FIG. 8) as in the prior art on the upper portion of the seat back 12, and if the overhang portion 120 is provided, it may be added to the body overhang portion 120 of the seated person. Seat back 1
Since no inconvenience such that the seatback 12 is easily damaged due to the application of a force in the twisting direction to 2 does not occur, the seatback 12 can be structurally well-balanced.

The present invention is not limited to the above embodiment, but includes the following contents.

(1) In the above embodiment, as shown in FIG. 5, the left end of the operating rod 42 is
Are fitted in the bottomed connection hole 41c formed in the right end face of the diaper in a sliding contact state, and the large diameter rod 41 and the operation rod 42 are connected so that they can relatively rotate around the axis. An operating piece 75 is integrally attached to the left end of the operating rod 42, and the operating piece 74 is rotated around the operating rod 42 to rotate the operating plate 74 around the first support shaft 54 via the connecting pin 74 c. However, instead of this, a through-hole is provided in the axial center portion of the large-diameter rod 41, and the operation rod 42 penetrates through the through-hole in a sliding state.
An operation piece 75 may be provided at the left end of the operation rod 42 protruding outside from the through hole. In this case, the operation plate 74 is rotated around the first support shaft 54 by the rotation of the operation piece 75 from the outside of the knuckle plate 5.

(2) In the above embodiment, the lock mechanism 7 is provided only on one side of the pair of knuckle plates 5, but in the present invention, the lock mechanism 7 is provided only on one side of the knuckle plate 5. The present invention is not limited to this, and may be provided on both knuckle plates 5. Seat back 1 set by doing this
The second posture is locked on both sides in the width direction of the back frame 15, which is advantageous in that the back frame 15 is not twisted and the set posture is surely maintained.

(3) In the above embodiment, the knuckle main body 51 is formed in a flat plate shape as a whole, and the spiral spring 6 is provided inside the knuckle main body 51. A concave portion recessed inward is provided at a portion where the large-diameter rod 41 is provided,
The spiral spring 6 may be provided in the recessed / recessed portion.
By doing so, the spiral spring 6 is provided inside the flat portion of the knuckle body 51, so that the conventional disadvantage when the spiral spring 6 is provided outside is eliminated, and the spiral spring 6 is not exposed to the outside. The appearance of the sheet 1 can be further improved.

[0059]

According to the knuckle structure of the seat according to the first aspect of the present invention, the bracket fixed to the rear both side surfaces of the seat bottom, the connecting rod inserted between the brackets, and the lower side of the seat back. A knuckle plate fixed to the surface corresponding to the bracket and rotatably supported around the connecting rod, a spiral spring for urging the seat back to incline forward, and operation of the operation lever To lock any posture of the seat back,
A lock mechanism for releasing the lock is provided, and the spiral spring is provided on the opposite surface side of the pair of knuckle plates.By operating the operation lever in one direction, the lock mechanism locks the knuckle plate and the bracket with each other. The rotation of the bracket around the connection axis can be restricted, and the set posture of the seat back can be fixed. In this state, by operating the operation lever in the other direction, the lock by the lock mechanism is released, and the seat back is urged by the urging force of the spiral spring so as to be urged to incline forward about the connection axis and to rotate. By returning the operation lever to the original direction when the seat back has reached the desired tilt angle, the seat back is locked by the lock mechanism at the desired tilt angle, and the seat back can maintain the tilt angle. .

Since the spiral spring is provided on the opposite surface side of the pair of knuckle plates, the spiral spring protrudes outward from the side surface of the seat as compared with the conventional one provided on the outer surface side of the knuckle plate. Occupation of space due to
The unsightly appearance can be eliminated, and the width dimension of the sheet can be increased by the absence of the spiral spring, and the appearance of the sheet can be improved.

Further, it is not necessary to provide an overhang-shaped overhanging portion above the space in which the spiral spring is provided. Therefore, when the overhanging portion is provided as in the prior art, the weight of the seated person overhangs. The torsional force acts on the seat back in addition to the part, which does not cause the disadvantage that the seat back is easily broken, and the seat back can be structurally balanced. This eliminates the need for the seat back to be over-equipped in terms of strength, which is extremely effective in reducing manufacturing costs.

According to the knuckle structure for a seat according to the second aspect of the present invention, the knuckle plate is integrally connected to the connecting rod supported by the bracket so as to be rotatable about its own axis. While the inner end is fixed to the connecting rod, the outer end is fixed to the bracket, and the inner rod is fixed to the inner rod by the biasing force of the spiral spring whose outer end is fixed to the bracket. It receives a force in the direction of pivoting around the center, whereby the seat back can be brought into a state of always falling forward.

Further, the lock mechanism includes a toothless gear fixed to the bracket so that the tooth surface is concentric with the connecting rod;
The knuckle plate is pivotally supported around the support shaft,
And a lock piece having teeth that mesh with the teeth of the toothless gear,
It is formed of an operating rod connected to an operating lever that is concentric with the connecting rod and that is rotatable relative to each other. When the operating lever rotates in one direction around the support shaft, the toothless gear and the lock piece mesh with each other. In addition, since the engagement between the toothless gear and the lock piece is released by the rotation operation in the same other direction, the rotation operation of the operation lever is transmitted to the lock piece via the connecting rod, and the operation is performed. Switching between a lock state in which the teeth of the lock piece mesh with the teeth of the missing gear in accordance with the operating direction of the lever, and an unlocked state in which the mesh between the teeth of the lock piece and the teeth of the missing gear is released. Can be easily performed.

Since the locked state is maintained by the engagement between the teeth of the lock piece and the teeth of the missing gear, the circumferential range of the tooth surface of the missing gear is 360 ° at the maximum. Whatever the range of the seat back attitude change range is set, the toothless gear can cope with that, and the locking mechanism can be made versatile. The engagement between the plurality of teeth of the lock piece and the plurality of teeth of the toothless gear makes it possible to reliably maintain the set state of the seat back.

Further, since the spiral spring is provided between the operation piece and the knuckle plate, the spiral spring is sandwiched between the operation piece and the knuckle plate, which is convenient for stabilizing the mounted state of the spiral spring. is there.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an embodiment of a seat to which a knuckle structure according to the present invention is applied.

FIG. 2 is an exploded perspective view showing one embodiment of a knuckle structure according to the present invention.

FIG. 3 is an assembled perspective view of the knuckle structure shown in FIG. 2;

FIG. 4 is a view on arrow A of FIG. 3;

FIG. 5 is a sectional view taken along line BB of FIG. 4;

FIG. 6 is an explanatory diagram for explaining the operation of the lock mechanism;
(A) is a state where the knuckle plate is locked so as not to rotate, (B) is a state where the lock is released,
(C) shows a state where the knuckle plate is tilted rearward.

FIG. 7 is a front view of a seat for explaining the operation of the present invention.

FIG. 8 is an explanatory front view illustrating a seat to which a conventional knuckle structure is applied.

[Explanation of symbols]

 Reference Signs List 1 seat 11 seat bottom 12 seat back 13 slider 14 bottom frame 15 back frame 2 knuckle structure 3 bracket 31 concave groove 32 shaft support 33, 33a shaft support hole 4 connecting rod 41 large-diameter rod 41a large-diameter portion 41b small-diameter portion 41c connection hole 41d Locking groove 42 Operating rod 42a Square pillar 42b Screw 5 Knuckle plate 51 Knuckle body 52 Protruding edge 53 Arc hole 54 First support shaft 55 Second support shaft 56 Second arc hole 57 Fastening hole 6 Spiral spring 61 Center end Part 62 Bending end part 7 Lock mechanism 71 Toothless gear 71a Shaft supporting hole 71b Gear side tooth surface 72 Lock piece 72a Locking hole 72b Lock one side tooth surface 72c Operation pin 73 Pressing piece 73a Pressing plate body 73b Stopper part 73c Mounting hole 73d Guided pin 74 Operation plate 74 Support hole 74b third arcuate slot 74c connecting pin 74d guide hole 75 operation lever 75a operated element body 75b operate pawl 75c outside Hamaana 75d accommodating space 76 coil spring (biasing means) 8 operating lever 81 square holes

Claims (2)

[Claims] 1. A seat knuckle structure for connecting a seat bottom as a seated seat and a seatback as a backrest provided at a rear end of the seat bottom so as to be capable of changing an inclination angle, wherein the seat has a knuckle structure. A pair of brackets in the width direction fixed to the rear side surfaces of the bottom, a connecting rod rotatably inserted between the brackets so as to be rotatable around its own axis, and the brackets on the lower side surfaces of the seat back. A pair of flat knuckle plates in the width direction that are correspondingly fixed and rotatably supported around the connecting rod, and a spiral spring that biases the seat back so as to incline forward. A lock mechanism for locking an arbitrary position of the seat back against the urging force of the spiral spring by operating the operation lever and releasing the lock. The buckle is provided on at least one of the opposing surfaces of the pair of knuckle plates, and the seat back has a width dimension such that an upper portion of the seat back does not project outward beyond the knuckle plate beyond the knuckle plate. A knuckle structure for a seat, characterized in that: 2. The connecting rod is supported by the bracket so as to be rotatable around its own axis. The knuckle plate is integrally connected to the connecting rod. An outer end portion is fixed to the bracket while being fixed to the connecting rod, and the locking mechanism includes a toothless gear fixed to the bracket so that a tooth surface is concentric with the connecting rod; A lock piece rotatably supported by a plate about a support shaft and having teeth that are always meshed with the teeth of the toothless gear by the urging force of the urging means; and the connecting rod concentric with the connecting rod. An operating rod connected to the operating lever, which is rotatable relative to the operating lever; and an operating gear fixed to the operating rod and operating the lock piece by a rotating operation of the operating rod in a predetermined direction. With 2. The knuckle for a seat according to claim 1, wherein the spiral knuckle is formed between the operating piece and the knuckle plate. Construction.