JPH04744Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) The present invention is a ratchet fitting for a seat chair, more specifically, a ratchet fitting for a seat chair, which is interposed at the connection point between the seat plate and the back plate, and This invention relates to a ratchet fitting used to change the inclination angle of a plate in stages.

(Prior art) Conventionally, as a ratchet fitting for this type of seat,
For example, as shown in Japanese Utility Model Application Publication No. 57-129452, the inclination angle of the backrest plate relative to the seat plate can be changed in stages, and the standing posture of the backrest plate at a predetermined angle relative to the seat plate can be changed in stages. Ratchet fittings for chairs are known which have the function of preventing excessive rotation in the folding direction. This prevents the backrest plate from folding in two if a person, especially a child, carelessly leans on the backrest plate from behind or pushes it playfully. This is to prevent the product from being folded into a shape and falling over, causing injury.
In order to achieve this purpose, in the above publication,
A stopper formed on the cam plate is brought into abutment with a claw piece to prevent the backrest plate from rotating in the folding direction beyond a predetermined upright position with respect to the seat plate.

However, the load applied to the stopper and the pawl is quite large, and the structure described above has a disadvantage in that there is a high risk of failure due to bending damage to the cam plate, breakage of the pawl, etc. due to insufficient strength.

(Purpose of the invention) Therefore, the object of this invention is to provide a more durable ratchet fitting for a seat that solves the above-mentioned drawbacks.

(Structure and Operation) The structure of this invention will be explained below based on the illustrated embodiment.

(First Embodiment) In the first embodiment of this invention shown in FIGS. 1 to 5, the ratchet fittings are attached to a fixing fitting 1 attached to the constituent frame A of the seat plate and to a constituent frame B of the backrest plate. It consists of a rotating metal fitting 2, a cam plate 3 which is pivotally supported by the fixed metal fitting 1 together with the rotating metal fitting 2, and a claw piece 4 which is pivotally supported by the fixed metal fitting 1.

The fixing fitting 1 is formed by bending a single metal plate, and includes a seat plate mounting tube 5 to which the frame A of the seat plate is attached, a pair of substantially circular side walls 66 facing each other, and a common structure therebetween. It consists of a housing 8 made up of a bottom wall 7. and the housing 8
Inside, the cam plate 3 and the ratchets 9 with the cam plate 3 interposed therebetween are rotatably supported by a shaft 10 provided approximately at the center of the side walls 6, 6, while the ratchet teeth 14 of the ratchet 9 A substantially L-shaped claw piece 4 that engages with the housing 8 is supported by a shaft 11 at a predetermined distance from the bottom wall 7 at a lower side of the seat plate mounting cylinder 5 in the housing 8. It is assumed that the force is applied in the direction away from the target.

The rotating fitting 2 includes a backrest plate mounting tube 13 to which the backrest plate component frame B is attached, and the claw piece 4 on the outer periphery.
Opposed 1 having a plurality of ratchet teeth 14 and one protruding stopper 15 interlocking with the
It consists of a pair of ratchets 9, 9, and like the fixture 1, it is constructed by bending a single metal plate.

The cam plate 3 has a guide surface 18 formed in an arcuate shape slightly larger than the ratchet 9 so as to restrict the engagement of the claw piece 4 with the ratchet tooth 14, and a guide surface 18 that allows the claw piece 4 to engage with the ratchet tooth 14. It has a substantially V-shaped concave portion 16, and a first contact surface 19 and a second contact surface 20 formed to abut against the contact portion 17 of the rotating metal fitting 2 on the circumferential surface.

Then, both the abutting surfaces 19 and 20 and the recessed portion 1
6, the angle between the backrest plate mounting cylinder 13 and the seat plate mounting cylinder 5 is 180 degrees, and the claw piece 4 is inserted into the recessed part 1 of the cam plate 3.
6, the second abutting surface 20 of the cam plate 3 abuts the abutting part 17 of the rotary fitting 2, while at the position where the angle is 90 degrees and the claw piece 4 engages with the concave part 16, 1 contact surface 19 is contact part 1 of rotating metal fitting 2
7.

The ratchet teeth 14 are configured to prevent the backrest plate mounting cylinder 13 from rotating in the unfolding direction with respect to the seat plate mounting cylinder 5, but to allow rotation in the folding direction. The claw pieces 4 are formed so as to engage with each other from approximately 180 degrees to approximately 90 degrees with respect to the seat plate mounting cylinder 5.

And stopper 1 formed on ratchet 9
Reference numeral 5 is such that it comes into contact with the upper surface side of the claw piece 4 at a position where the rotating metal fitting 2 is further rotated by a predetermined angle in the folding direction from the upright position where the angle is approximately 90 degrees.

In the above configuration, when the backrest plate mounting cylinder 13 is in the unfolded state with respect to the seat plate mounting cylinder 5 as shown in FIG. It is in occlusion with the ratchet tooth 14. When the backrest plate mounting tube 13 is rotated in the folding direction from this state, the ratchet teeth 14 push down the claw pieces 4, and the occlusal position and angle of the adjacent ratchet teeth 14 are changed, while the cam plate 3 Since the guide surface 18 is formed to be large by the ratchet 9, rotation of the cam plate 3 is prevented when the claw piece 4 passes over the tip of the ratchet tooth 14, and the position of the cam plate 3 relative to the fixture 1 is not changed. . At the changed position, rotation of the backrest plate mounting cylinder 13 in the unfolding direction is prevented by the action of the ratchet 9 and the claw piece 4. In this way, the claw piece 4 and the ratchet tooth 14
By changing the occlusion position with respect to the seat plate mounting cylinder 5, the angle of inclination of the back plate mounting cylinder 13 with respect to the seat plate mounting cylinder 5 can be changed stepwise for each pitch of the ratchet teeth 14. Further, when the backrest plate mounting cylinder 13 is rotated in the folding direction and the first abutment surface 19 of the cam plate 3 abuts the abutment part 17 of the rotation fitting 2, the ratchet 9
As the cam plate 3 rotates, the claw piece 4 rides on the guide surface 18 of the cam plate 3, and the ratchet 9
The occlusion with is released. When further rotated in the same direction, the stopper 1 of the ratchet 9 will move as shown in Fig. 4.
5 comes into contact with the claw piece 4, and the claw piece 4 is pushed down and comes into contact with the bottom wall 7 of the fixture 1, thereby preventing the backrest plate mounting cylinder 13 from rotating in the folding direction relative to the seat plate mounting cylinder 5 thereafter. be done. At this time, the claw piece 4 rides on the guide surface 18 of the cam plate 3 and the engagement between the ratchet teeth 14 and the claw piece 4 is released, so that the rotation of the backrest plate mounting cylinder 13 in the unfolding direction is prevented. is so-called free until the abutting part 17 of the rotating metal fitting 2 abuts against the second abutting surface 20 of the cam plate 3, and as shown in FIG. When the cam plate 3 also rotates and the backrest plate mounting cylinder 13 and the seat plate mounting cylinder 5 are in a substantially straight line, the claw pieces 4 fit into the recesses 16 of the cam plate 3 again and engage the ratchet teeth 14. bite,
The same effect as described above can be performed.

(Second Embodiment) The second embodiment is shown in FIGS. 6 to 8, and differs from the first embodiment only in the cam plate 3'. That is, the same number of ratchet teeth 22 are formed on the cam plate 3', the tooth tips of which are slightly more inclined than the ratchet teeth 14 of the ratchet 9 only at the rear with respect to the rotation permissible direction. The first contact surface 19' of the cam plate 3' has both ratchet teeth 14,
22 are formed so as to abut against the contact portion 17 of the rotating metal fitting 2 in an overlapping state (see FIG. 6).
The second contact surface 20' is formed so as to come into contact with the contact portion 17 when the backrest plate mounting tube 13 is rotated by a half pitch of the ratchet teeth 14 of the ratchet 9. The other configurations are substantially the same as those of the first embodiment, and corresponding parts are given the same reference numerals and detailed explanations will be omitted.

In the above configuration, when the backrest plate mounting cylinder 13 is in the unfolded state with respect to the seat plate mounting cylinder 5, as shown in FIG. and bite. When the backrest plate mounting cylinder 13 is rotated in the folding direction from this state, the first contact surface 19' of the cam plate 3' is in contact with the contact part 17 of the rotation bracket 2, so the cam is rotated as the ratchet 9 moves. Plate 3' also rotates, and claw piece 4 engages ratchet teeth 22 and ratchet 9 of cam plate 3'.
The engagement position of the pawl piece 4 with the ratchet tooth 14 of the ratchet 9 and the ratchet tooth 22 of the cam plate 3' is changed. At the changed position, rotation of the backrest plate mounting cylinder 13 in the unfolding direction is prevented by the action of the ratchet 9 and the claw piece 4. In this way, the occlusion position between the pawl piece 4 and the ratchet teeth 14 can be changed, and the inclination angle of the back plate mounting cylinder 13 with respect to the seat plate mounting cylinder 5 can be changed in stages for each pitch of the ratchet teeth 14. This is the same as the first embodiment. However, in the first embodiment, in order to rotate the backrest plate mounting cylinder 13 from this position in the deployment direction,
Once the backrest plate mounting tube 13 is folded until it is prevented from rotating in the folding direction, it is unfolded until the backrest plate attachment tube 5 and the backrest plate attachment tube 13 are on a straight line, and then the desired angle is reached again. Although it required a folding operation,
In the second embodiment, by rotating the backrest plate mounting tube 13 by half a pitch in the folding direction,
Since the pawl piece 4 rides on the ratchet teeth 22 of the cam plate 3', the backrest plate mounting cylinder 13
When the cam plate 3' is rotated half a pitch in the direction of deployment, the cam plate 3'
The second abutting surface 20' of the rotary fitting 2 abuts the abutting part 17, and the cam plate 3' rotates together with the ratchet 9.
When the claw piece 4 is further rotated in the deployment direction, the cam plate 3'
When the pawl piece 4 is moved from the ratchet tooth 22 of the cam plate 9 to the ratchet tooth 14 of the ratchet 9 and further rotated in the same direction, the pawl piece 4 moves to the ratchet tooth 22 of the cam plate 3' as shown in FIG. By rotating the backrest plate mounting cylinder 13 in the folding direction when the desired angle is reached, the claw piece 4 is moved to the ratchet 9.
The angle can be adjusted by meshing with the ratchet teeth 14 of the cam plate 3' and the ratchet teeth 22 of the cam plate 3'.

The action of the stopper 15 of the ratchet 9 is exactly the same as in the first embodiment (see FIG. 8).

(Effect of the invention) This invention has a pair of opposing latches 9 of the rotating bracket 2 having the backrest plate mounting cylinder 13 and the ratchets of the ratchets 9 in the housing 8 of the fixing bracket 1 having the seat plate mounting cylinder 5. A claw piece 4 that engages with the tooth 14 is pivotally supported, and the engagement of the claw piece 4 with the ratchet tooth 14 prevents rotation of the rotating metal fitting 2 in the deployment direction with respect to the fixed metal fitting 1; A cam plate 33' is inserted between the ratchets 9 and pivotally supported together with the ratchet 9, so that the cam plate 3 controls the engagement and release of the claw piece 4 with the ratchet teeth 14. In the metal fitting, a stopper 15 is formed on the ratchet 9, and the contact of the stopper 15 with the claw piece 4 prevents rotation of the rotating metal fitting 2 in the folding direction beyond a predetermined angular standing posture with respect to the fixed metal fitting 1. Since it is configured to prevent rotation of the rotating metal fitting in the folding direction beyond the predetermined angle of the upright position with respect to the fixing metal fitting 1, the stoppers 15, 15 that prevent rotation are Since the rotating metal fitting 2 is formed in a pair of opposing ratchets 9, the load applied to the rotating metal fitting 2 is directly transferred to the stopper 1.
5.15, and since there are two stoppers for each ratchet fitting for a seat according to this invention, there are four stoppers in total for the seat, which prevents children from accidentally leaning against the backrest plate. Even if the ratchet is damaged, the load is distributed to four locations, reducing the load applied to one location, increasing the strength and improving safety.Moreover, this configuration only forms a stopper on the ratchet. It has an extremely simple structure and can be manufactured at low cost.

Also, like conventional products, the angle can be adjusted freely.

[Brief explanation of the drawing]

The drawings show an embodiment of this invention. Fig. 1 is a perspective view of the chair ratchet fitting of this invention attached to a seat, and Fig. 2 is a partially cutaway view of the first embodiment. Figures 3 to 5 are perspective views of Figures 1 and 5.
FIGS. 6 to 8 are longitudinal sectional views of the second embodiment. 1...Fixing bracket, 2...Rotating bracket, 3, 3'...
...Cam plate, 4...Claw piece, 5...Seat plate mounting tube, 8...
...housing, 9... ratchet, 13... backrest plate mounting tube, 14... ratchet tooth, 15... stopper.

Claims (1)

[Scope of utility model registration request] Housing 8 of fixture 1 with seat plate mounting tube 5
A pair of opposing ratchets 9 of the rotary fitting 2 having the backrest plate mounting cylinder 13 and a claw piece 4 that engages with the ratchet teeth 14 of the ratchet 9 are pivotally supported inside. While the cam plates 3 and 3' are inserted between the ratchets 9 and rotated together with the ratchets 9, the cam plates 3 and 3' are configured to prevent the rotating metal fittings 2 from rotating in the deployment direction with respect to the fixed metal fittings 1 by engaging the teeth 14. The claw piece 4 is supported by this cam plate 3.
In this ratchet fitting, a stopper 15 is formed on the ratchet 9, and when the stopper 15 comes into contact with the claw piece 4, rotation with respect to the fixed fitting 1 is controlled. A ratchet fitting for a seat chair, characterized in that it is configured to prevent the movable fitting 2 from rotating in the folding direction beyond a predetermined angle of upright position.