WO2011021311A1 - Rocking chair - Google Patents

Abstract

A chair configured in such a manner that, when the chair is rocked, the seat portion rises and at the same time moves backward, wherein the safety of the chair is ensured so that person’s fingers do not get caught. The front part of a seat receiving body (7) and a base (2) are connected by a front link (23), and the rear part of the seat receiving body (7) is connected to a pivotable member. In rocking motion, the seat receiving body (7) is pulled backward by the pivotable member, and as a result, the seat receiving body (7) rises and at the same time moves backward. A downward facing, upper female fitting section (24) is provided in the seat receiving body (7), and the front link (23) is connected to the upper female fitting section (24). A downward facing, rear engagement claw (21) is provided to the rear part of the seat receiving section (7), and a rear pin (20) is connected to the rear engagement claw (21). A large space (S1) is provided between the seat receiving body (7) and the base (2), and as a result, person’s fingers do not get caught.

Description

Rocking chair

The present invention relates to a rocking chair.

[Correction based on Rule 91 09.08.2010]
The rocking chair supports the back tilt of the backrest with elastic means such as a spring or rubber. Generally, the moment accompanying rocking acts on the elastic means as it is. Often uses coil springs and torsion bars.

However, this not only increases the cost of the elastic means, but also has a problem that the member for storing the elastic means (generally, a base provided at the upper end of the leg) is enlarged. On the other hand, Patent Document 1 discloses a chair in which a seat moves up and backwards when a backrest tilts backward by a link mechanism similar to a parallel link mechanism.

That is, in Patent Literature 1, the front part of the seat and the base are connected to the front link in a side view forward tilted posture (accurately tilted forward with respect to the vertical line) with a pin, while the backrest is attached. The back frame and the seat are connected by a pin at a position in front of the connecting portion of the back frame to the base, and the front portion of the back frame and the front link are similar to a parallel link mechanism. In Patent Document 1, a coil spring is used as an elastic means, and the coil spring is disposed behind the pivot point of the back frame.

According to the configuration of Patent Document 1, since a part of the weight of the seated person acts to return the backrest even when locking, the force that acts on the elastic body when locking is very small. It can be said that it can contribute to cost reduction and downsizing of the base part. More specifically, the moment acting on the backrest during rocking is generally proportional to the weight of the seated person, but the load acting to push down the seat when rocking is also proportional to the body weight. Even if they are different, the same degree of rocking feeling can be obtained with one kind of elastic means.

On the other hand, the use of rubber as an elastic means for imparting resistance to rocking is described in Patent Document 2, for example. In Patent Document 2, the seat and the backrest are integrally connected, and a rectangular parallelepiped rubber is disposed between the base fixed to the upper end of the leg and the seat. Naturally, the rubber is arranged at a position (back) considerably away from the backrest and the pivot point of the seat.

US Pat. No. 6,709,058 Japanese Utility Model Notice Showa 43-13628

Now, in the chair where the seat rises when rocking, even if a person inserts a finger in the seat or downward, it is safe to prevent the finger from being caught between the seat and the base when the backrest is turned back. It is necessary to secure. However, in Patent Document 1, no consideration is given to ensuring such safety.

In Patent Document 1, the connection between the front link and the base, the connection between the front link and the seat, and the connection between the back frame and the seat are performed by inserting pins (shafts). Since the operation of positioning the member and inserting a pin and attaching a retaining material such as a snap ring has to be performed, there is a problem that the assembly of the chair takes time and productivity is poor.

Now, if rubber is used as an elastic means to give resistance to rocking, it can be said that the structure of the chair can be simplified considerably. However, in office swivel chairs, coil springs and torsion bars are frequently used as elastic means, and rubber is not often used. This is because the rearward tilt angle of the backrest cannot be made very large when rubber is arranged at a position considerably away from the pivot point of the backrest as in Patent Document 2.

The present invention has been made in view of such a current situation, and intends to provide a chair in which a seat part is raised and lowered in a more improved form when rocking. In addition, the present invention discloses many improvements that can be widely applied to chairs in general, and provision of these improvements can also be developed as a subject (object) of the present application.

A chair according to the present invention includes a base provided at an upper end of a leg, a seat disposed above the base, a back support device connected to the base so as to be tiltable rearwardly, a backrest provided on the back support device, and the back. A support device and elastic means for imparting resistance to back tilting of the backrest, and a front connection portion connected to the base via a front link on a lower surface of the seat portion, and a back support device Of these, a rear connecting portion connected to a portion in front of the pivot point is provided, and the seat portion is lifted and retracted when the backrest tilts backward.

And in 1st invention, even if a person inserts a finger between the said seat part and a base by setting it as the form which protruded the front connection part and the rear connection part of the said seat part downward, it can pinch | interpose. There is no space.

The present invention can be developed in various ways. Examples thereof are listed as the second to sixth inventions. Of these, the second invention is the first invention, wherein the front connecting portion and the front link of the seat portion are connected, the front link and the base are connected, and the rear connecting portion and the back support device of the seat portion. At least one of the three connections is a system in which the seat part or the front link is fitted by moving the seat part or the front link in a direction perpendicular to the rotational axis of the back support device.

According to a third invention, in the first or second invention, the base has a box shape with an upward opening having a front wall at the tip thereof, and the front link is rotatably fitted to the front portion of the base. While the left and right horizontally long front support shafts are arranged, the front link is formed with a space in which the front plate of the base fits, and the front inner surface of the space and the front wall of the base The space to be formed is set to have a size enough to insert a human finger, and a forward flange is formed at the upper end of the front wall of the base.

According to a fourth invention, in the first invention, the rear connecting portion of the base and the back support device are connected by a rear pin, and an upper cover having a receiving portion for the rear pin is attached to the base. An upward wall surrounding the rear pin is formed on the lower surface of the seat portion, and a downward projecting wall is formed on the lower surface of the seat portion from the outside, and is interposed between the upward wall and the downward projecting wall. Has only a narrow gap between which one cannot insert a finger.

According to a fifth invention, in the first or second invention, the base has a box shape with an upward opening, while the front link has only one and is arranged at the left and right intermediate portions of the seat portion. Yes. When only one front link is used, the lateral width is preferably as large as possible. For example, it is preferable that the size is equal to or larger than the lateral width of the base.

In a sixth aspect based on the first aspect or the second aspect, the elastic means is rubber, and the rubber is disposed in the vicinity of a rotation fulcrum of the back support device.

In the present invention, since the front connecting part and the rear connecting part protrude downward, a space is provided between the seat part and the base so that there is enough space even if a person inserts a finger. In the chair where the seat rises, the fingers can be prevented from being pinched between the seat portion and the base, thereby ensuring safety.

As a means for preventing finger pinching, it is conceivable to cover with a large cover so that hands and fingers cannot be inserted between the seat and the base, but this not only increases the cost, but the cover is conspicuous. The aesthetics may not be good. On the other hand, the present invention can secure safety by devising the connecting structure, so that it is possible to suppress the increase in cost by eliminating the need for a large cover, and it is possible to realize a clean appearance and improve aesthetics.

When the second invention is adopted, in assembling the chair, at least one of the three connections of the connection between the seat and the front link, the connection between the front link and the base, and the connection between the seat and the back support device is Since it is connected by moving the seat or moving the front link, it is possible to eliminate or reduce the trouble of inserting the pins one by one, thereby improving the efficiency of assembling the chair.

Since the front link rotates during locking, it is necessary to prevent fingers from being caught between the front link and the base. In this regard, in the third invention, even if a person inserts his / her finger into the front surface of the base, there is a space larger than the finger between the base and the front link, so that the finger is sandwiched between the front surface of the base and the front link. In addition, even if an attempt is made to insert a fingertip into the upper surface of the front plate in the base, this is blocked by the forward-facing flange of the base, so that the finger is not pinched between the upper end surface of the front plate of the base and the front link.

When locking, the rear connecting part moves back and forth while moving up and down, so it is necessary to consider preventing finger pinching at the rear connecting part. In this regard, when the configuration of the fourth invention is adopted, the connecting portion between the rear connecting portion of the seat portion and the front end portion of the back support device is formed by the upward protruding wall and the downward protruding wall of the seat portion before and after locking. Since it is covered, safety can be ensured.

[Correction based on Rule 91 09.08.2010]
Although it is possible to use a plurality of front links and arrange them on the left and right, in this case, the labor for managing the members increases and the assembly work becomes troublesome. In this regard, when the fifth invention is adopted, since there is only one front link, it is possible to reduce the labor of member management and the labor of assembling.

Now, when a rubber is used as an elastic means for locking and resistance is given to the backward tilting of the back support device, the amount of the rubber being crushed becomes smaller as it approaches the rotation fulcrum of the back support device. In the sixth aspect of the invention, since the rubber is close to the axial center where the first member and the second member rotate relative to each other, a large locking angle can be obtained even if it is compact. Thereby, it can contribute to simplification of the structure of a chair.

[Correction based on Rule 91 09.08.2010]
(A) is a fragmentary perspective view of the chair which concerns on embodiment, (B) is a side view. FIG. FIG. It is the separation figure seen from the lower part. FIG. (A) is a partially separated perspective view of the elasticity adjusting mechanism, (B) is a separated perspective view for showing the mounting structure of the back frame. It is a sectional side view. (A) is a separated rear view of the main part, (B) is a partial perspective view of the seat receiving body. FIG. . (A) is a perspective view of an upper cover, (B) is a separated perspective view of an upper cover and a base. It is the perspective view which looked at the circumference of a rear connection part from the lower part. It is a figure for demonstrating the mounting aspect of a stopper, (A) is an isolation | separation perspective view, (B) is an isolation | separation top view. It is a figure for demonstrating the mounting aspect of a stopper, (A) is the isolation | separation perspective view in the fracture | ruptured state, (B) is a sectional side view. (A) is the elements on larger scale of Drawing 7, (B) is a perspective view in the state where the front link was turned over. (A) (B) is a fractured perspective view of a front link. (A) is sectional drawing for showing fitting of a front link and a seat receiving body, (B) is a sectional view in the state where a front link and a seat receiving body were fitted together. (A) is a separated perspective view of a front link and a seat receiving body, and (B) is a separated perspective view of a front link and a base. (A) is a separated perspective view of an operation unit, and (B) is a separated perspective view for showing a mounting structure of a back frame. It is a separate perspective view of the principal part. (A) is an exploded perspective view of the member, (B) is a perspective view with the receiving member turned upside down, and (C) is a partially broken perspective view of the base. It is a separation perspective view of the portion centering on the operation unit. It is a sectional side view in the location of fixed type rubber. (A) is a side cross-sectional view at the location of the lock body, and (B) is a side cross-sectional view in a state where the movable rubber is functioned. (A) is a separated plan view of the operation unit, and (B) is a perspective view of the operation mechanism section. (A) is a perspective view of a back cover, (B) is a separated perspective view of an operation unit, and (C) is a partial perspective view of an operation mechanism section. It is the perspective view which looked at the chair from the upper part. (A) and (B) are separate perspective views. It is the fragmentary perspective view which turned the back plate over and arranged with the back frame. It is the elements on larger scale of FIG. FIG. 30 is a partially enlarged view of FIG. 29. It is the elements on larger scale of the upper part of FIG. (A) is the elements on larger scale of a back frame, (B) is a partial top view of a backrest. It is a perspective view of the lower part of a back board. (A) is a separated plan view for explaining the attachment of the mesh skin material, (B) is a broken perspective view of the upper frame, and (B) is a broken perspective view of the lower frame. (A) is a separated rear view of the back plate and the mesh skin material, (B) is a sectional view taken along the line BB of (A), (C) is a sectional view taken along the line CC of (A), (D) FIG. 4A is a DD sectional view of (A), and FIG. 8E is an EE sectional view of (A). (A) is a longitudinal side view for explaining the tension state of the mesh-like skin material, (B) is a side cross-sectional view of the backrest taken along the line XXXVIB-XXXVIB in FIG. 32 (A), and (C) is the backrest. It is the sectional side view cut | disconnected by XXXVIC-XXXVIC location of FIG. 32 (A). (A) is a cross-sectional plan view of the backrest taken along the line XXXVIIA-XXXVIIA in FIG. 29, (B) is a cross-sectional plan view of the backrest taken along the line XXXVIIB-XXXVIIB in FIG. 29, and FIG. FIG. 30 is a cross-sectional plan view of the backrest taken along the line XXXVIIC-XXXVIIC in FIG. 29; (A) is a schematic front view of a cushion unit in which a cushion is covered with a bag-like skin material, (B) is a sectional view taken along line BB of (A), (C) is a sectional view taken along line CC of (A), (D) is a DD sectional view of (A). FIG. 37 is a view similar to FIG. 36 regarding a cushion type backrest. It is a figure similar to FIG. 37 regarding the backrest of a cushion type.

Next, an embodiment of the present invention will be described with reference to the drawings. This embodiment is applied to a swivel chair used for office work or the like. In the following explanation and claims, the terms “front and rear” and “left and right” are used to specify the direction, but this term defines the direction in which a person sitting in a normal posture on a chair is facing forward. Yes. The front view is seen from the direction opposite to the seated person.

(1). Overview of the chair As shown in FIG. 1, the chair is composed of a leg device displaying only the leg strut (gas cylinder) 1, a base 2 fixed to the upper end of the leg strut 1, and a seat disposed above the base 2. It has a body 3 and a backrest 4 on which a seated person can rest. An armrest device can be attached to the base 2 as an optional item.

As can be understood from FIG. 2, the seat body 3 has a seat plate (seat inner shell) 5 made of synthetic resin and a cushion material 6 arranged on the upper surface thereof, and the cushion material 6 has an outer skin such as a cloth. The material is stretched. In addition, the seat plate 5 is attached to a synthetic resin seat receiver (seat outer shell) 7 so that it can be moved back and forth. Therefore, in the present embodiment, the seat portion 8 is configured by the seat body 3 and the seat receiver 7.

As shown in FIG. 2, the backrest 4 includes a synthetic resin back frame 10 and a synthetic resin back plate 11 fixed to the front surface thereof. The back plate 11 is in the form of horizontal stripes with horizontally elongated holes, and a mesh-like skin material 12 is stretched on the back plate 11. A cushion material may be disposed on the front surface of the back plate 11. In this case, the cushion material is covered with a bag-shaped skin material. The back frame 10 includes a vertically long left and right side frame 13, an upper frame 14 that connects the upper ends thereof, and a lower frame 14 that connects the lower ends of the left and right side frames 13. A back plate 11 is fixed to the base plate.

The back frame 10 includes left and right forward arm portions 16 extending in series from the side frame 13, and a joint portion 17 having an upper plate 17a and left and right side plates 17b is integrally connected to the left and right forward arm portions 16. . A swing member 18 made of a metal plate is connected to the rear portion of the base 2 so as to be tiltable by a left and right longitudinal first shaft 19, and a joint portion 17 of the back frame 10 is connected to the swing member 18 with a screw 40 (FIG. B) See)).

[Correction based on Rule 91 09.08.2010]
Accordingly, in the present embodiment, the back support device described in the claims is configured by the swing member 18, the forward-facing arm portion 16 of the back frame 10, and the joint portion 17, and the backrest 4 includes the first shaft 19. Tilt around the center. Since the left and right forward arm portions 16 of the back frame 10 are integrally connected by the joint portion 17, the rigidity of the left and right forward arm portions 16 is remarkably high.

The swing member 18 is integrally provided with a support arm 18a extending forward and upward in an inclined posture in side view, and the seat support 7 is easily attached to the swing member 18 at the rear end of the left and right support arms 18a. The rear pin 20 is inserted as an example of the male engaging portion for connection. For example, as shown in FIG. 5 and FIG. 8 (B), the lower surface of the seat receiver 7 is provided with a female engaging portion for easily connecting the seat receiver 7 to the swinging member 18 at the rear portion. As an example, a pair of left and right rear engaging claws 21 that are hooked and fitted to the rear pin 20 from behind are integrally formed. For this reason, when the backrest 4 tilts backward, the seat receiver 7 and the seat body 3 are pulled backward.

On the other hand, as shown in FIG. 5, for example, the base 2 is made of a metal plate and has a box-like shape with an upward opening having left and right side plates 2a. Then, a left and right laterally long second shaft 22 which is the front shaft described in the claims is attached to the front portion of the base 2, and a single structure front link 23 is rotatably connected to the second shaft 22. Yes. Further, the upper end of the front link 23 is rotatably fitted in an upper female fitting portion 24 formed on the seat support 7. Therefore, when the seated person leans on the backrest 4, the seat receiving body 7 is pulled backward by the swinging member 18, and the front link 23 is rotated accordingly, and the seat portion 8 moves upward while moving upward.

As shown in FIG. 5 and FIG. 10 (A), an upper cover 25 is mounted on the base 2 from above, and the rear pin 20 is supported by the upper cover 25. The base 2 is covered with a lower cover 26 from below. An operation unit 29 having an operation mechanism unit 27 and a back cover 28 is disposed at the rear portion of the base 2. The operation unit 29 switches the magnitude of the resistance against locking and controls the locking state.

(2) Relationship between the base 2, the swinging member 18 and the back frame 10 Hereinafter, details of each part will be described. First, the relationship among the base 2, the swing member 18, and the back frame 10 will be described. As described above, the base 2 has a box shape that opens upward. For example, as shown in FIGS. 5 and 7, the base 2 has a shape that is open downward at a substantially central portion of the inside of the base 2 in a side sectional view. 1 An inner bracket 31 is welded, and a bush 32 is fixed to the inner bracket 31 and the bottom plate of the base 2, and the leg support 1 is fitted to the bush 32 from below.

A second inner bracket 33 having an upward opening is fixed to the first inner bracket 31 so that the base end portion of the armrest device is inserted from the lateral direction into the space surrounded by the inner brackets 31 and 33. It has become. As shown in FIG. 5, the side plate 2 a of the base 2 has a hole for inserting the base end portion of the armrest device, and the left and right end portions of the second inner bracket 33 are exposed to the outside of the base 2. The downward piece 33a is formed in the front-end | tip, and the base end part of an armrest apparatus is fastened with a screw | thread with the downward piece 33a.

The side plate 26a of the lower cover 26 has a hole 34 into which the base end portion of the armrest device is fitted, and the hole 34 is closed by a removable cover plate 35. Further, a holding groove hole 36 for holding the second shaft 22 is formed in the front portion of the side plate 26 a in the lower cover 26. The clamping slot 36 is constricted at the upper end thereof, so that the lower cover 26 is fitted into the second shaft 22 by being deformed against elasticity.

The swing member 18 is a basic form having an upper plate and left and right side plates 18b. The base 2 is surrounded by the left and right side plates 18b from the outside, and a first shaft is formed on the left and right side plates 2a of the base 2 and the left and right side plates 18b of the swing member 18. 19 penetrates. The first shaft 19 is attached to the base 2 via a bush. The support arm 18a of the swing member 18 extends from the side plate 18b.

The left and right third shafts 37 are inserted through the rear portions of the left and right side plates of the swing member 18. On the other hand, for example, as shown in FIG. 4, the forward arm portion 16 of the back frame 10 has a thick wall shape with a certain right and left width, and the forward end of the left and right forward arm portion 16 is fitted to the first shaft 19. An opening groove 38 is formed, and a downward opening groove 39 that fits from the upper part to the distal end portion of the third shaft 37 is formed at a position behind the forward opening groove 38.

Both the opening grooves 38 and 39 are not opened to the left and right outside, and therefore the first shaft 19 and the third shaft 37 are held by the forward arm portion 16 so as not to be left and right. For this reason, the first shaft 19 and the third shaft 37 do not need a retaining means such as a snap ring.

As can be easily understood from FIG. 6B, the joint portion 17 of the back frame 10 overlaps the swing member 18 from above, and further, a resin-made pressing member 41 overlaps the lower surface of the swing member 18. (The fastening structure will be described later). The back frame 10 and the swing member 18 rotate integrally.

As shown in FIG. 6A, a pair of left and right fixed rubbers 44 as an example of an elastic body are interposed between the pressing member 41 and the base 2, and the fixed rubbers 44 are attached to the base 2. The receiving member 45 is attached. Even in the non-sitting state, the fixed rubber 44 is compressed by the pressing member 41. In other words, the fixed rubber 44 is pretensioned.

As described above (see FIG. 3), the operation unit 29 includes the operation mechanism unit 27 and the back cover 28 to which the operation mechanism unit 27 is attached. The back cover 28 has left and right side plates 28a, and a sandwiching portion 28b for attaching the back cover 28 to the third shaft 37 is opened forwardly inside the left and right side plates 28a. As shown in FIG. 5, the back cover 28 has a flange portion 28 c that overlaps the rear upper surface of the swing member 18, and the flange portion 28 c is fixed to the swing member 18 with a screw 42 that is schematically shown by a line. ing.

The operation mechanism unit 27 has a center shaft 46 and an outer cylinder 47. The central shaft 46 is for adjusting the hardness of locking, and one end portion thereof protrudes outside the outer cylinder 47, and a strength adjusting lever 48 is provided here. On the other hand, the outer cylinder 47 is for controlling the locking state, and a lock lever 49 is provided at one end thereof.

The side plate 18b of the swing member 18 has a relief groove 50 in which the operation mechanism 27 is fitted, opened backward. As shown in FIG. 5, the outer cylinder 47 of the operation mechanism unit 27 is provided with a lock body 51 protruding downward.

On the other hand, as shown in FIG. 6A, a slider 52 that moves in the axial direction when the central shaft 46 is rotated is attached to the central shaft 46, and a movable rubber 53 is attached to the slider 52. . When the slider 52 is moved left and right, the movable rubber 53 is supported by the receiving member 45 in a strong state, and the movable rubber 53 is not supported by the receiving member 45 (it is freely rotated without being compressed). Switch. These details will be described later.

(2) Relationship between the seat portion 8, the upper cover 25, and the swing member 18 Next, the relationship between the seat portion 8, the upper cover 25, and the swing member 18 will be described. As already described, the seat portion 8 includes the seat body 3 and the seat receiver 7. A number of slits are formed in the seat plate 5 so as to bend (sink) when seated. For example, as can be understood from FIG. 2, the seat plate 5 is gently curved in an upwardly concave shape in a front view, the front end portion is bent with a large curve downward, and the rear portion is warped upward with a gentle curvature. On the other hand, the seat support 7 is also basically gently curved upwardly concave in a front view, but has a number of ribs extending vertically and horizontally to ensure strength.

Since the relationship with the present invention is thin, the details are omitted, but the seat plate 5 is mounted on the seat receiving body 7 so as to slide back and forth by a certain size. In FIG. 12, two pairs of guide claws 54 protrude upward on both the left and right sides of the seat support body 7, but these four guide claws 54 fit in a long groove formed in the seat plate 5 so that they cannot be pulled upward. Thus, the seat body 3 is held so as to be slidable back and forth.

As described with reference to FIGS. 5 and 8B, a pair of left and right rear engaging claws 21 are integrally provided on the lower surface of the rear portion of the seat receiver 7. Side protrusions 55 are provided on the left and right outer sides of the rear engaging claws 21 so as to protrude downward. The side protrusions 55 serve as stoppers and the rear pins 20 are held so as not to be removed. Therefore, it is not necessary to provide a retaining means such as a snap ring for the rear pin 20, and as a result, the processing cost and the assembly cost can be reduced.

For example, as can be understood from FIG. 1B, the left and right side protruding walls 55 of the seat support 7 cover the tip of the support arm 18a of the swinging member 18 from the left and right outer sides. Further, as shown in FIGS. 5 and 8B, a front projecting wall 56 is integrally continuous with the left and right side projecting walls 55. Accordingly, the left and right rear engaging claws 21 are surrounded by the side protruding wall 55 and the front protruding wall 56 from three directions. For this reason, even if a person inserts a fingertip below the seat receiving body 7, the rear pin 20 and the rear engaging claw 21 are not touched, and safety is ensured.

When locking, the rear pin 20 is pulled backward by the rear engaging claw 21, but when the locking is returned, the seat 7 must be pushed forward by the rear pin 20. Therefore, for example, as shown in FIGS. 11 to 13, a stopper 57 for holding the rear pin 20 so as not to be relatively movable back and forth is attached to the seat support 7.

This stopper has a substantially T-shape when viewed from the side, and has a hook-like locking piece 57a projecting forward at the lower end. The locking piece 57a has a lateral width larger than that of the main body, and a recess 57b that opens forward is formed on the left and right outer portions so that a fingertip or the like can be hooked. Further, the distal end surface of the locking piece 57a is inclined in a slightly forward inclined posture with respect to the vertical line in a side view.

As shown in FIGS. 12 and 13, the seat receiver 7 is formed with a storage hole 60 into which the stopper 57 is inserted and attached from above. The storage hole 60 is substantially L-shaped in plan view in accordance with the plan view form of the stopper 57, and forms a support portion 61 that receives the upper portion of the stopper 57 and holds it so that it cannot fall. Then, as clearly shown in FIG. 11, stopper receiving portions 62, which are engaged with the locking pieces 57 a of the stopper 57 from below, are projected downward on the left and right sides of the front protruding wall 56 of the seat receiving body 7. ing.

When the stopper 57 is inserted into the storage hole 60, the locking piece 57a is once elastically deformed. When the stopper 57 is completely inserted, the locking piece 57a returns to its original state and engages with the stopper receiving portion 62 from below. As a result, the stopper 57 is held so that it cannot be removed. Since the stopper 57 is positioned on the front side of the rear pin 20, when the rear pin 20 moves forward due to the return of locking, the stopper 57 is pushed by the rear pin 20 and the seat receiving body 7 moves forward. That is, the rear pin 20 and the seat support 7 are held so as not to move relative to each other.

As described with reference to FIGS. 5 and 10A, the rear pin 20 is supported by the upper cover 25 made of synthetic resin. Next, the upper cover 25 will be described. For example, as shown in FIG. 10A, the upper cover 25 is formed with a pair of left and right pin receiving portions 64 that receive the rear pins 20. The pin receiving portion 64 is recessed in an upward concave shape so as to receive the rear pin 20 in a wide area (so as to come into surface contact). In addition, the left and right inner sides of the pin receiving portion 64 are recesses 65, which are for releasing the rear engaging claws 21.

The upper cover 25 includes an upward side wall 66 that surrounds the pin receiving portion 64 from the left and right sides, an upward front wall 67 that is integrally continuous with the front end of the left and right upward side wall 66, and an upward direction that is integrally continuous with the rear end of the left and right upward side wall 66. A rear wall 68 is projected. As shown in FIG. 7, the front projecting wall 56 of the seat receiving body 7 is disposed in the vicinity of the front side of the upward front wall 67 of the upper cover 25. In other words, there is only a small gap between the upward front wall 67 and the front projecting wall 56 that allows a person to insert a finger, for example, 5 mm or less.

For this reason, even if a person tries to insert his fingertip into the rear pin 20 from the front, it cannot be touched by being guarded by the front protruding wall 56 of the rear connecting portion 7 and the front wall 57 of the upper cover 25. The front surface of the upward front wall 67 and the rear surface of the front projecting wall 56 are curved in a rearward convex shape in a side view, and therefore, the seat support body 7 is allowed to retreat while rising, and the seat support Even if the body 7 moves, the distance between the front surface of the front wall 67 and the front protruding wall 56 does not increase.

Further, it is conceivable that a person tries to apply a finger from the side toward the rear pin 20, but this point is guarded by the side protruding wall 55 of the seat receiving body 7 and the upward side wall 66 of the upper cover 25. . The distance between the side protruding wall 55 of the upper cover 25 and the upward side wall 66 of the upper cover 25 is set to 5 mm or less, and the side protruding wall 55 covers the upward side wall 66 from the side even if the seat support 7 moves. The state has been secured. In the state where the seat receiving body 7 is fully lowered, as can be understood from FIG. 1B, there is a margin even if a person's finger is applied between the front projecting wall 56 of the seat receiving body 7 and the upper cover 25. A certain interval (for example, 20 mm or more) is vacant. Therefore, the finger is not sandwiched between the front projecting wall 56 of the seat receiver 7 and the upper cover 25.

Further, as can be understood from FIG. 7, there is a sufficient space between the lower surface of the front protruding wall 56 of the seat support 7 and the upper surface of the upper cover 25 even if a person's finger is applied. Therefore, a finger is not sandwiched between the lower surface of the front protruding wall 56 and the upper surface of the upper cover 25.

Furthermore, as shown in FIG. 10, for example, an upward inner wall 69 protruding toward the upward front wall 67 is provided at the inner end of the upward rear wall 68 of the upper cover 25. Therefore, even if a person tries to hit the rear pin 20 or the rear engaging claw 21 from behind, the finger cannot be hit by the guard with the upward rear wall 68 and the upward inner wall 69. Is not sandwiched.

Further, as can be understood by combining FIG. 7 and FIG. 10, the seat receiver 7 is fully lowered between the seat rear body 7 and the upward rear wall 68 and the upward inner wall 69 of the upper cover 25. , There is a vacant space (up and down spacing) even if a person inserts a finger. Therefore, the finger is not pinched between the upward rear wall 68 or the upward inner wall 69 of the upper cover 25 and the seat support 7. As described above, the presence of the downward projecting walls 55 and 56 and the upward walls 66 to 69 prevents the person from pinching the finger between the rear pin 20 and the rear engaging claw 20 and its peripheral portion, thereby ensuring safety.

The upper cover 25 has left and right side plates 25a, but as can be understood from FIG. 5, the left and right side edges of the upper cover 25 and the left and right side edges of the lower cover 26 are set to overlap. In other words, the left and right side surfaces of the upper cover 25 and the left and right side surfaces of the lower cover 26 are set to be substantially the same surface.

As shown in FIG. 10B, the upper cover 25 is provided with a pair of left and right front engaging claws 71 and a pair of left and right rear engaging claws 72 protruding downward. The front engagement claw 71 has a saddle shape facing backward in a side view, and the rear engagement claw 72 has a saddle shape facing forward in a side view.

On the other hand, the base 2 is formed with a pair of left and right inward flanges 2b, and the front engaging claws 71 of the upper cover 25 are hooked to the front edge of the inward flange 2b in the base 2. The first inner bracket 31 provided on the base 2 is formed by bending a pair of left and right upright pieces 31a to support the upper cover 25 at the upper horizontal portion of the upright piece 31a, and the rear engaging claws of the upper cover 25. 72 is engaged with the rear edge of the upright piece 33a.

(3) Relationship between the front link 23 and the base 2 Next, a connection structure between the front link 23 and the base 2 will be described. The front link 23 is a molded product of synthetic resin, and has a rough plate-like or block-like appearance roughly due to the combination of many plate-like ribs. For example, as shown in FIG. 17B, a lower inner female fitting portion 78 that fits on the second shaft 22 inside the base 2 and a second inner female fitting portion 78 outside the base 2 are provided at the lower end portion of the front link 23. A lower side female fitting portion 79 fitted to the biaxial shaft 22 is provided.

A slit groove 80 is formed between the lower inner female fitting portion 78 and the lower side female fitting portion 79 so as not to hit the side plate 2 a of the base 2. The left and right side bearing groove portions 79 have a bag shape (see FIG. 17), and the second shaft 22 is held by the outer wall 79a so that the left and right sides cannot be removed. It is also possible to adopt only the lower inner female fitting portion 78 or only the lower side female fitting portion 79 as the lower female fitting portion.

The lower female fitting portions 78 and 79 have a U-shaped cross section so as to be fitted to and detached from the second shaft 22, and a pair of left and right bearing bushes 81 are mounted in the lower inner bearing groove portion 78. The bearing bush 81 is made of a resin having a small friction coefficient and high wear resistance. As clearly shown in FIGS. 14 (A) and 17, an engagement claw 82 is formed at the opening edge of the bearing bush 81. The engaging claw 82 is fitted into the engaging hole 83 formed in the lower inner bearing groove portion 78 against elasticity. Accordingly, the left and right bearing bushes 81 function as bearings at the lower end portion of the front link 23, and other portions are not in contact with the second shaft 22. The lower inner bearing groove portion 78 extends to the left and right and has high rigidity.

Since the bearing bush 81 is U-shaped in a side view, it can be attached to the second shaft 22 by one-touch fitting from above (it can also be fitted in a tilted posture). As shown in FIG. 14, the front end portion of the base 2 is a front wall 2 c that is gently curved in a front-facing convex shape in a side sectional view, while the back side of the lower inner bearing groove portion 78 of the front link 23 is As an example of the retaining means, a plurality of restriction ribs 84 that are close to the front wall 2c of the base 2 are formed. With the restriction ribs 84, the front link 23 is tilted forward (use posture) from the second shaft 22. Exiting is prevented.

In addition, it is assumed that the seat holder 7 is grasped by hand and the chair is lifted. In this case, the front link 23 must be in a substantially vertical posture in order for the front link 23 to come out of the second shaft 22. Since the retreat limit of the body 7 is determined, the front link 23 does not rotate to a posture close to the vertical posture, and therefore the front link 23 does not come out of the second shaft 22.

For example, as clearly shown in FIG. 14, the front link 23 is formed with an intermediate bottom plate 93 that divides the front link 23 into a half that is close to the upper female fitting portion 24 and a half that is close to the second shaft 22. In the upper half close to the upper female fitting portion 24 across the upper space, there is an upper space S3 that opens substantially upward when assembled as a chair, and in the lower half close to the second shaft 22 across the intermediate bottom plate 93 Is surrounded by the intermediate bottom plate 93, the back plate 96, and the female fitting portions 78 and 79, and a lower space S4 is opened in a downward opening (a forward opening in a vertical posture).

The front plate 2c of the base 2 enters the lower space S4, and the regulation rib 84 is disposed in the lower space S4. A space that is a part of the lower space S4 exists between the intermediate bottom plate 93 of the front link 23 and the front plate 2c of the base 2, but this space can be afforded even if a person inserts a finger. Since a certain size is set, a finger is not sandwiched between the intermediate bottom plate 93 (front inner surface of the lower space S4) of the front link 23 and the front plate 2c of the base 2. Further, a forward flange 2d is formed at the upper end of the front plate 2c in the base 2, and even if a human fingertip tries to go inside the base 2 beyond the front plate 2c, it is blocked by the forward flange 2d. Therefore, a finger is not pinched between the front link 23 and the base 2.

(3). Relationship between the front link 23 and the seat support 7 Next, a connection structure between the front link 23 and the seat support 7 will be described. For example, as shown in FIG. 17 (A), an upper female fitting portion 24 that is laterally long and opened downward is projected downward from the front portion of the seat support 7 as an example of a front connecting portion. (The upper female fitting portion 24 can also be referred to as a “front protrusion having a downward opening groove”). On the other hand, as an example of the upper connecting portion, a boss portion 86 that fits into the upper female fitting portion 24 of the seat receiver 7 is integrally provided at the upper end portion of the front link 23.

The upper female fitting portion 24 has bearing portions 87 having U-shaped cross sections on both left and right sides, and the left and right bearing portions 87 penetrate vertically. A front restricting protrusion 88 extending in the left-right direction between the left and right bearing portions 87 is formed on the front portion 24a of the upper female fitting portion 24 so as to protrude into the groove. On the other hand, the rear portion 24b of the upper female fitting portion 24 has an engagement claw 89 having a side view when facing the inside of the groove at the left and right intermediate portions, and between the engagement claw 89 and the left and right bearing portions 87. A pair of left and right rear restricting protrusions 90 positioned in the groove and facing the groove are formed. These front and rear restricting projections 88 and 90 constitute a means for preventing the upper female fitting portion 24 from coming off. Note that only one of the front and rear restricting projections 88 and 90 is sufficient.

On the other hand, as shown in FIG. 15, the boss part 86 of the front link 23 basically has a form close to a prism, and the left and right side parts thereof are in surface contact with the left and right bearing parts 87 of the seat support 7. An arcuate portion 91 is formed. The boss portion 86 is supported at both ends supported by the left and right side plates 23 a, and the front cover portion 92 is located at a position positioned in front of the boss portion 86 with the front link 23 in a vertical posture. And are formed at some distance.

The upper space S3 described above is vacant between the front cover portion 92 and the intermediate bottom plate 93 and the boss portion 86. For this reason, the boss portion 86 is fitted into the upper female fitting portion 24, and the front link 23 is inserted. Is allowed to rotate around the boss 86. The left and right side plates 23a of the front link 23 are positioned on the left and right outer sides of the upper female fitting portion 24. Therefore, the front link 23 is held so as not to move left and right. In addition, a pair of reinforcing ribs 94 are integrally connected to the boss portion 86 with the left and right intermediate portions therebetween. The reinforcing rib 94 is connected to the front cover portion 92 and the intermediate bottom plate 93.

As described above, the boss portion 86 basically has a prismatic shape. However, as can be easily understood from FIG. 16, the front link 23 is positioned vertically in the portion excluding the left and right bearing portions 87. In the state of the posture, the cross section is substantially rectangular in the side view, and the lateral width dimension W is set to be approximately the same as the distance dimension E between the front and rear restricting projections 88, 90 in the upper female fitting portion 24. The vertical length L is set to be longer than the distance E between the front and rear restricting projections 88 and 89 in the upper female fitting portion 24.

For this reason, when the front link 23 is placed in a posture that is substantially orthogonal to the seat receiving body 7 in a side view (a non-use posture that cannot be used as a chair), the boss portion 86 can be easily inserted into the upper female fitting portion 24. However, in the use state in which the seat receiving body 7 is largely tilted forward, the upper female fitting portion 24 does not come out even if the seat receiving body 7 is raised upward. The boss portion 86 is inserted into the upper female fitting portion 24 by elastically deforming the engaging claw 89.

Therefore, when the front link 23 is attached to the seat support 7 in advance before assembling the chair, the front link 23 will not fall out even if the front link 23 is hung from the seat support 7. As shown in FIG. 15A, the boss portion 86 has a large number of slots 95 opened in a direction orthogonal to the axial center. This is formed by equalizing the wall thickness as much as possible. It is a measure to prevent later sink marks.

As shown in FIG. 14, a gap S2 exists between the front end of the front cover part 92 and the front lower end of the upper female fitting part 24 in the front link 23. The gap S2 is formed by the front link 23. Even if it rotates, there is only a little (5mm or less). For this reason, a person does not pinch a finger at the position of the gap S2.

Further, even if a finger is inserted into a position between the front end portion of the front link 23 and the rear surface of the upper female fitting portion 24, the finger is guarded by the reinforcing rib 94 and the intermediate bottom plate 93 of the front link 23 and the upper female fitting portion are provided. Since the upper space S <b> 3 with respect to 24 has an interval of 20 mm or more, the intermediate bottom plate 93 and the upper female fitting portion 24 do not pinch fingers. As shown in FIG. 14, a guard plate 98 is provided on the inner surface of the front lower portion 92 of the front link 23 so as to be in contact with or in close contact with the lower end of the rear portion 24 b of the upper female fitting portion 24. Therefore, even if the person forcibly inserts the fingertip into the upper space S3, the fingertip hits the guard plate 98 and cannot be inserted any further. Therefore, a finger is not sandwiched between the front cover portion 92 of the front link 23 and the upper female fitting portion 24.

As clearly shown in FIGS. 1 and 16, the upper female fitting portion 24 protrudes greatly downward from the lower surface of the seat receiver 7, and thus the front link 23, the upper female fitting portion 24, Is greatly protruded from the lower surface of the seat receiving body 7 so that a large space S1 in which any number of human fingers can enter between the seat receiving body 7 and the base 2 (or the upper cover 25) with a margin is provided. Forming.

Further, as clearly shown in FIG. 16, the back surface of the upper female fitting portion 24 and the lower surface of the seat support 7 are continuous with an arc surface (curve) having a considerably large curvature. There is no sense of incongruity even if a finger is applied to the base of the female fitting portion 24.

(4). Summary of the structure of the base part and the seat part In the above configuration, the chair is assembled generally in the following procedure. That is,
1) Fix the base 2 to the leg support.
2) The second shaft 22 and the upper cover 25 are attached to the base 2, the swing member 18 is connected to the base 2 by the first shaft 19, and the operation unit 29 is fitted from behind.
3) The back frame 10 is attached in such a procedure that the forward opening groove 38 is first inserted into the third shaft 37 from behind and then the downward opening groove 39 is fitted into the third shaft 37.
4) The fixed rubber 44 is compressed by tilting the back frame 10 backward. In this state, the rear pin 20 is inserted into the support arm 18a of the swinging member 18, and then the back frame 10 is returned to place the rear pin 20 on the upper cover 25. (In this state, the fixed rubber 44 is slightly compressed, so that the rear pin 20 is in strong contact with the pin receiving portion 64 and pre-tensioning is applied during locking).
5) The lower female fitting portions 78 and 79 are fitted to the second shaft 22 by setting the front link 23 in a substantially vertical posture, and then the rear engagement claw 21 is hooked on the rear pin 20 from behind, and then the seat support 7 Front link 23 to
6) Attach the stopper 57, and then attach the seat 3 to the seat receiver 7.
It is assembled in the procedure. The attachment of the backrest 4 may be performed after the attachment of the seat body 3 or may be performed before. The front link 23 may be connected to the seat receiver 7 in advance.

The attachment of the front link 23 to the seat receiver 7, the attachment of the front link 23 to the base 2, and the attachment of the seat receiver 7 to the rear pin 20 (swing member 18) require a pin insertion operation. Since the front link 23 and the seat support 7 can be moved in a direction perpendicular to the axis of each of the shafts 19, 22, and 37 without any trouble, the efficiency of assembling the chair can be greatly improved.

As described above, the space (S1 to S4, etc.) existing at the position of the moving member is large enough to allow a person to insert a fingertip, or narrow enough that a person cannot insert a fingertip. Because of the spacing, even if a person inserts his / her hand into the lower surface of the seat 7, the finger is not pinched and is safe.

(6). Advantages of the embodiment relating to the base and the seat (a)
In the present embodiment, the seat portion 3 can be attached to the base 2 by moving it in a direction orthogonal to the rotational axis of the front link 24, but this attachment structure can be generalized as follows.

In a chair including a base provided at the upper end of a leg as a first member and a seat disposed above the base, the seat is connected to the base via a link; A second connecting part connected to the second member attached to the base, and a connection between the first connecting part and the link, a connection between the link and the seat part, and a second connecting part, A rocking chair in which at least one of the three members connected to the second member is fitted to each other by relatively moving the seat portion in a direction orthogonal to the rotation axis of the link.

As can be understood from this description, in the generalized configuration, the link may be arranged at the rear part of the seat part, or the seat part and the base may be connected by the front and rear links.

(7) Supplement to the seat and the base The present invention can be embodied in various ways other than the above embodiment. For example, the front link can be inserted into only one of the base and the seat receiving body, and the other can be connected by inserting a pin. As the structure of the lower connecting part that connects the front link and the base, it is possible to form a boss part on the front link and fit it into the lower female fitting part provided on the base. As a configuration for connecting the seat receiver, an upper female fitting portion may be formed on the front link and a boss portion may be formed on the seat receiver. Of course, the female fitting part and the male fitting part can be developed in various structures.

When a male fitting part is provided in the base as a connecting structure between the front link and the base, the male fitting part does not necessarily have to be a shaft, but a boss part made of a resin molded product, die cast product, sheet metal processed product, etc. It is also possible to provide. It is also possible to attach a shaft to the seat (seat receiver) and fit the upper female fitting part of the front link to this. In this case, a regulating rib as a retaining means is formed on the front link. You may form in a seat part and may form in both. In forming the boss portion as a non-circular restricting portion as a retaining means, an elliptical shape or an oval shape can be adopted as the cross-sectional shape of the restricting portion.

In the above embodiment, the back support device is configured by the swing member and the back frame. However, the forward arm portion of the back frame and the swing member in the embodiment may be integrated, or The back frame in which the frame of the backrest and the back column are integrally formed can be used as the back support device as it is.

Furthermore, the seat support and the base may be connected by a rear link, and the back support device may be connected to the rear link. That is, the seat receiver may be connected to the back support device via some intermediate member. Further, the back support device and the seat support body may be connected by connecting the seat support body to the base by the front link and the rear link so as to be movable up and down and back and forth.

(8). Arrangement Mode of Fixed Rubber in Elasticity Adjustment Mechanism Next, the elasticity adjustment mechanism will be described with reference to FIGS. First, the arrangement of the fixed rubber 44 will be mainly described. For example, as shown in FIG. 22, a pair of left and right fixed rubbers 44 are disposed between the pressing member 41 and the base 2, and the fixed rubbers 44 are attached to a receiving member 45 attached to the base 2. . The fixed rubber 44 and the receiving member 45 are arranged behind the pivot point of the swing member 18.

Further, the fixed rubber 44 is disposed close to the first shaft 19, and the swinging member 18 is tilted backward at a large angle (for example, 15 to 20 °) by the compression of the fixed rubber 44. Can do.

How close the fixed rubber 44 is to the first shaft 19 is determined by the relationship between the required rearward tilt angle (stroke) and the height of the fixed rubber 44. When using the smallest possible rubber as the fixed rubber 44, the fixed rubber 44 needs to be as close as possible to the outer peripheral surface of the first support shaft 19. In general, the distance between the first shaft 19 and the fixed rubber 44 is preferably several mm, and can be said to be within a few dozen mm at most. It can be said that the distance from the rotation axis is preferably 10 to 20 mm.

The fixed rubber 44 has a fan-like block shape when viewed from the side, and is arranged so that the upper surface 44a and the lower surface 44b are positioned on the extension line of the axis of the first shaft 19 as shown by dotted lines in FIG. ing. For this reason, each part of the fixed rubber 44 is compressed evenly by the pressing member 41. In other words, the load accompanying pre-tensioning and locking acts equally on each part of the fixed rubber 44. For this reason, durability can be improved by eliminating one-sided contact.

The receiving member 45 is made of resin, and has left and right fixed rubber mounts 101 to which left and right fixed rubbers 44 are mounted, for example, as shown in FIG. Also provided on the lower surface of the pressing member 41 is a rubber mount portion 101 into which the fixed rubber 44 is fitted so that it cannot be displaced.

Between the left and right fixed rubber mounts 101, a movable rubber 53 for receiving a movable rubber 53 (details will be described later) to make the resistance against locking strong, and movable even when locked A movable rubber escape portion 104 for releasing the rubber 53 so as not to be compressed is formed in a state where the rubber 53 is arranged side by side.

As shown in FIG. 22, the bottom plate of the base 2 is substantially horizontal, while the fixed rubber 44 is substantially vertically symmetrical with a horizontal plane passing through the axis of the first shaft 19 in side view. For this reason, the fixed rubber mount 101 is inclined in a posture inclined backward with respect to the horizontal plane.

Also, the fixed rubber mount portion 101 includes a rear rib 101a for holding the fixed rubber 44 so as not to be displaced backward and a side rib 101b for holding the left and right not shifted. It protrudes upward. The movable rubber cradle 103 is higher than the fixed rubber mount 101.

For example, as shown in FIG. 21 and FIG. 22, between the pressing member 41 and the fixed rubber 44 and between the fixed rubber 44 and the fixed rubber mount portion 101, it is horizontally long and has a semicircular cross section. A protrusion 44c is provided. On the other hand, the rubber mounting portion 101 of the pressing member 41 and the receiving member 45 is formed with a receiving groove 105 into which the protrusion 44c is fitted. Instead of providing the protrusion 44c, a pin may be interposed.

As described above, the movable rubber cradle 44 has a height higher than that of the fixed rubber mount portion 101, while the movable rubber relief portion 104 is higher than the upper surface of the fixed rubber mount portion 101 as shown in FIG. It is low (deep). The bottom surface of the movable rubber relief 104 is also set so that its extension line passes through the axial center of the first shaft 19 or the vicinity thereof in a side view.

The receiving member 45 is a molded product of resin, and a large number of ribs (or voids) are formed on the bottom. As shown in FIG. 20B, left and right positioning pins 106 project from the bottom surface of the receiving member 45, while the base 2 has a positioning hole 107 into which the positioning pin 106 fits. For this reason, the receiving member 45 is held so that it cannot be displaced and cannot be dropped without being screwed. Of course, fixing with screws is acceptable.

The pressing member 41 is a resin product, and generally has a block-like appearance that is substantially rectangular in the left-right direction, but has many voids for weight reduction. Then, as shown in FIG. 23A, the joint portion 17 of the back frame 10 is fastened to the swing member 18 with screws 40.

As shown in FIG. 20, a protrusion 41a is formed on the upper surface of the pressing member 41. On the other hand, as shown in FIG. 19, the swing member 18 is provided with a hole 18c into which the protrusion 41a of the pressing member 41 is fitted. Yes. Since the pressing force of the fixed rubber 44 is always acting as the pretension on the swing member 42, the fitting relationship between the protrusion 41a and the hole 18c is maintained. Therefore, the pressing member 41 is held so as not to be displaced without being fixed with screws. Of course, it may be fastened with screws.

(9). Operation Unit Tilt Control Device Next, the operation unit 29 will be described. First, the tilt control device will be mainly described. As described above, the operation unit 29 includes the operation mechanism unit 27 and the back cover 28 to which the operation mechanism unit 27 is attached.

[Correction based on Rule 91 09.08.2010]
The back cover 28 has left and right side plates 28a. A vertically long outer rib 28e is formed on the inner side of the left and right side plates 28a, and a sandwiching portion 28b that fits on the third shaft 37 opens forward in the outer rib 28e. Yes. The clamping portion 28b is fitted into the third shaft 37 by being deformed against elasticity.

For example, as shown in FIG. 23B, the flange portion 28c of the back cover 28 is fixed to the upper surface plate 18a of the swing member 18 with a screw 108.

For example, as shown in FIG. 18, the strength adjusting lever 48 and the lock lever 49 are arranged such that the strength adjusting lever 48 is located outside and the lock lever 49 is located inside. Further, both levers 48 and 57 are arranged with different postures in side view so that a person can easily operate them. One end portion of the outer cylinder 47 is a large-diameter portion 47 a, and the shaft portion of the strength adjustment lever 48 is rotatably held by the large-diameter portion 47 a, and the central shaft 46 is connected to the shaft portion of the strength adjustment lever 48. Fitted so that relative rotation is impossible.

As shown in FIG. 25, a lock body 51 protruding from the axial center is integrally provided at the end of the outer cylinder 47 opposite to the lock lever 49. On the other hand, an inner rib 110 that hits the lock body 51 from the inside is formed in the back cover 28, and an inner end portion 47 b of the outer cylinder 47 is fitted in a bearing hole 111 formed in the inner rib 110. That is, the base portion of the lock body 51 is surrounded by the outer rib 28e and the inner rib 110 from both the left and right sides. An engagement groove hole 112 into which the other end 47c of the outer cylinder 47 is fitted is formed in the ter rib 28e. The engagement slot 112 has a constricted shape with a narrow opening.

As shown in FIG. 25, the other end portion 47 c of the outer cylinder 47 is formed with a Nusumi groove 113 having a flat outer peripheral surface. The Nusumi groove 113 of the outer cylinder 47 is parallel to the engagement groove hole 112. By adopting the posture, it can be fitted into the engagement slot 112, and when it is fitted and rotated to the use posture, it is held so as not to be detached. A stopper piece 114 for preventing the outer cylinder 47 from moving inward is formed on the other end 47c.

As shown in FIG. 23A, the lock body 51 has a posture that protrudes substantially downward from the outer cylinder 47, and has two steps of a first step portion 115 and a second step portion 116 facing the base 2. Has a part. The 1st step part 116 is located in the front end side. On the other hand, as shown in FIG. 25, first to fourth engagement grooves 117a to 117d are formed on the back surface of the lock body 51, and these engagement grooves 117a to 117d are formed from the rear side. A stopper 118 is selectively fitted. The stopper 118 is attached to a pocket part 119 formed in the back cover 28 so as to move only in the forward and backward direction, and is urged in the forward direction by the block-shaped elastic body 120.

As can be understood from FIG. 23A, the lock body 51 can come into contact with the outward support flange 2f provided on the rear wall 2e of the base 3 from above. In FIG. 23A, the lock body 51 is in a locked posture in which the first step portion 115 faces the upper surface of the support flange 2f. In this state, the backrest 4 is in a completely locked state in which the backrest 4 hardly tilts backward. Further, the stopper 118 is fitted in the second engagement groove 117b, so that the lock body 51 is held in the posture.

When the outer cylinder 47 is rotated counterclockwise in the state of FIG. 23A, the lock body 51 has an intermediate posture in which the second step portion 116 faces the support flange 2f, and the second step portion 116 has the support flange 2c. Switch to a free posture facing the outside. In the intermediate posture, when the backrest 4 tilts to a range of about half of the maximum tilt range, the second step portion 116 comes into contact with the support flange 2f, thereby restricting the back tilt range of the backrest 4 to about half of the maximum stroke. . In this intermediate posture, the stopper 118 is fitted in the third engagement groove 117c. It is also possible to lock in a state where it is tilted backward.

Furthermore, in the free posture, the locking body 51 does not hit the support flange 2c when locking, and therefore the backrest 4 tilts freely within the maximum tilting range. In this free state, the stopper 118 is fitted in the fourth engagement groove 117d.

(10). Movable rubber in the operation unit Next, an operation mechanism of the movable rubber 53 in the operation mechanism unit 27 will be described. As described above, the operation mechanism unit 27 has the central axis 46. For example, as can be understood from FIG. 25B, the distal end portion of the central shaft 46 is supported by the other outer rib 28e of the back cover 28, and a snap ring 122 is attached to the distal end to prevent the removal. In the center shaft 46, between the inner rib 110 of the back cover 28 and the other outer rib 28e, for example, as shown in FIG. 21 and FIG. A cam 123 is fitted.

The slider 52 is slidably fitted to the central shaft 46 and protrudes forward, and a movable rubber 53 is mounted on the lower surface thereof. The slider 52 opens downward, so that the movable rubber 53 is held so that it cannot be displaced in the left-right direction and the front-rear direction. Also, as shown in FIG. 25, a groove 53a is formed on one side of the movable rubber 53, while a rib (not shown) that fits into the groove 53a is formed on the slider 52. Is blocking. The movable rubber 53 may be bonded to the slider 52.

The slider 52 and the movable rubber 53 are slidably inserted in a space 124 (see FIG. 18) formed in the pressing member 41. The movable rubber 53 is also shaped like a fan in side view. Further, as shown in FIG. 21, the left and right guide projections 125 are provided at the tip of the slider 52, and the guide groove 126 into which the guide projection 125 is fitted is provided at the front end portion of the pressing member 41. The slider 52 and the movable rubber 53 slide stably left and right without touching up and down. The guide means may have another structure.

For example, as shown in FIG. 24, the slider 52 has a cylindrical body 127 fitted to the central shaft 46 and a case portion 128 surrounding the cylindrical body 127, and the case portion 128 has a rib 130 (see FIG. A) is held in a group slidable left and right. The case portion 128 is urged toward the strength adjustment lever 48 by a spring 129.

The cylindrical body 127 is formed with a female cam groove 131 having a gap extending toward the strength adjusting lever 48 in a plan view, while the operating cam 123 holds the cylindrical body 127 from the outside. It has a bifurcated shape. Therefore, the operating cam 123 has a cam surface 123 a that is tapered in plan view and overlaps the female cam groove 131. The operation cam 123 is fixed to the central shaft 46 so as not to be relatively rotatable and slidable.

Therefore, when the strength adjustment lever 48 is rotated, the slider 52 moves left and right by the guide action of the operating cam 123 and the female cam groove 131. A step portion 132 that engages with the flat portion 134 of the opening edge of the female cam groove 131 is formed at the tip of the working cam 123.

As shown in FIG. 24A, in a state where the operating cam 123 is fitted in the female cam groove 131, the slider 52 is retracted by the spring 129 and the fitting state is maintained. When the slider is thus retracted, the movable rubber 53 is positioned above the movable rubber relief 104 in the receiving member 45, and therefore the movable rubber 53 does not act as a resistance when locking. . That is, the elasticity adjusting device is in a weak state where resistance to rocking is small.

When the operating cam 123 is rotated in the direction of the arrow in FIG. 24B with the slider 52 retracted, the slider 52 is pushed away from the strength adjustment lever 48 against the spring 129, and the operating cam 123 The slider 52 is held in the advanced state by the step portion 132 coming into contact with the opening edge of the female cam groove portion 131. In this forward state, the movable rubber 53 is located above the movable rubber cradle 103, and therefore the movable rubber 53 acts as a resistance when rocking. That is, the elasticity adjusting device is in a strong state with a large resistance when rocking.

(11). Summary of Elasticity Adjustment Mechanism As described above, the fixed rubber 44 and the movable rubber 53 are formed in a fan shape (or trapezoidal shape) when viewed from the side. The pressure acts, and therefore, it is excellent in durability, and a comfortable rocking state can be obtained while maintaining a uniform relationship between the degree of backward tilt and the degree of increase in resistance.

When the protrusion 44c is provided on the fixed rubber 44 as in the present embodiment, there is an advantage that the fixed rubber 44 can be reliably compressed to prevent the shift of the fixed rubber 44 during locking and can be compressed into a uniform state. .

Also, when the movable rubber and the tilt control device are incorporated in the operation unit 29, the seated person can adjust the elasticity and switch the lock with one hand, so that the operability is excellent.

(12). Advantages of embodiment of elastic adjustment mechanism (a)
In this embodiment, rubber is used as the elastic means for locking, but this point can be widely applied to rocking chairs. This point can be generalized as follows.

A base provided at an upper end of the leg; a seat disposed above the base; a back support device connected to the base so as to be tiltable rearwardly; a backrest provided on the back support device; and a rear tilt of the back support device The rubber is configured to be compressed by being sandwiched between the first member and the second member that rotate relatively during locking. A rocking chair in which the rubber is provided close to the rotational axis of the first member and the second member.

This generalized configuration (first configuration) can be suitably embodied. For example, as the second configuration, a pressure equalizing means for uniformly compressing the rubber can be provided. This equalization means can improve the durability of rubber. As a specific example of the equalizing means, the rubber is set so that the extension line on the upper surface and the extension line on the lower surface pass through the rotation fulcrum of the back support device or the vicinity thereof in a side view.

(13). Advantages of embodiment of elastic adjustment mechanism (b)
Now, what is well known as an elasticity adjusting device in a rocking chair is to change the initial load of the elastic means by rotating the screw type handle.

However, when it is necessary to adjust the elasticity steplessly, the screw-type handle is useful, but it cannot be applied to a simple method that requires only two or three steps of adjustment, for example. On the other hand, Japanese Utility Model Publication No. 04-96254 discloses a mechanism for changing the resistance to rocking according to the weight of the seated person, which can change the elastic force according to the seated person's preference. It is not a thing. In view of such a current situation, it can be said that there is a demand for an elasticity adjusting device that can be easily operated by a seated person.

This embodiment corresponds to such a current situation, and the pressure area of the rubber is changed as means for changing the elastic force of the elastic means. This is generalized as follows. *

A base provided at an upper end of the leg; a seat disposed above the base; a back support device connected to the base so as to be tiltable rearwardly; a backrest provided on the back support device; and a rear tilt of the back support device The elastic means for imparting resistance to the chair has a structure in which the elastic restoring force changes when the pressure area changes, and the pressure area of the elastic means is controlled by a person operating the lever. The elasticity adjustment device which changes is provided. A spring can also be used as the elastic body.

This invention (first configuration) can be developed in various ways. For example, in the second configuration, the elastic means includes a main elastic body that is pre-pressed before locking and a sub-elastic body that can be selected between a pressurized state and a non-pressurized state by the elasticity adjusting device. ing. As a means for switching the sub-elastic body between the pressurized state and the non-pressurized state, the sub-elastic body (movable rubber) may be moved as in the embodiment, or the pressing means may be moved to the pressure position and non-pressurized. It may be moved to a position.

By the way, when the elasticity is adjusted only by changing the initial load on the elastic means, the load per unit area (stress) on the elastic means is changed by adjusting the elasticity, so that the sag progresses quickly. There is a fear. On the other hand, if the pressure area of the elastic body is changed, the elasticity can be changed without changing the load per unit area on the elastic means, so the load on the elastic means can be reduced and the durability can be improved. It is particularly suitable when a rubber material is used for the elastic means.

(14). Advantages of embodiment of elastic adjustment mechanism (c)
As described above, the screw type elastic adjustment device is popular. However, since this is incorporated in the base of the chair, the replacement is troublesome, and it is difficult to respond to a request to easily switch between two steps or three steps. On the other hand, Japanese Patent Publication No. 2002-142899 discloses that a cylindrical body protruding laterally is provided on a base, and a tilt control device is incorporated in this cylindrical body. However, in this configuration, it is very troublesome to assemble the tilt control device and replace the parts.

The present embodiment takes into account such a current improvement. That is, the elasticity adjusting device or the like is unitized. This is generalized as follows.

A base provided at an upper end of the leg; a seat disposed above the base; a back support device connected to the base so as to be tiltable rearwardly; a backrest provided on the back support device; and a rear tilt of the back support device The elastic means for elastically supporting the elastic means, and the elasticity adjusting device for adjusting the resistance of the elastic means at the time of locking, or the tilt control device for regulating the back tilt of the backrest. The elasticity adjusting device or the tilt control device has an operation mechanism portion having an operation lever, and a support material attached to the back support device or the base, and the operation unit is incorporated into the support material by the operation unit. It is configured.

In this case, “the elasticity adjusting device or the tilt control device” includes “the elasticity adjusting device and the tilt control device”. The second configuration is expandable as a second configuration. In the second configuration, the operation mechanism section includes an elastic adjustment device having an operation lever that rotates about a concentric axis and a tilt control device. ing.

This configuration enables efficient assembly of the elasticity adjusting device and the tilt control device. Also, parts can be easily replaced by removing the operation unit. When the elasticity adjusting device and the tilt control device are incorporated into one operation unit as in the above-described embodiment, there is an advantage that the assembling work efficiency of the chair can be further improved.

(15). Backrest Overview Next, the backrest 4 will be described. First, an outline will be described. The invention disclosed below is based on the invention disclosed in Japanese Patent Application No. 2009-248738. The inventors are Keisuke Tanaka and Hiroyuki Ito, who belong to Itoki Corporation. ) And Koda Wada. The back frame 10 is a molded product made of a synthetic resin such as polypropylene or nylon resin, but an aluminum die cast product or a sheet metal processed product can also be adopted.

For example, as shown in FIG. 26, the upper frame 14 of the back frame 10 is formed in a state of opening largely forward in plan view so that the back plate 11 is attached only to the left and right side portions thereof. In other words, a horizontally long upper space 213 is vacant between the upper frame 14 and the back plate 11. Therefore, an upper exposed portion 11a that can be seen from behind is present on the upper portion of the back plate 11. For this reason, not only can a person grasp the upper frame 14 of the back frame 10, but also the upper end portion of the back plate 11 can be elastically deformed.

As shown in FIG. 1B and FIG. 26, the side frame 13 of the back frame 10 is bent in a forward projecting shape in a side view so that the portion slightly higher than the waist of the seated person is at the front. . For this reason, the side frame 13 has an apex 214.

The back plate 11 is not attached to the back frame 10 at a portion below the apex portion 14 of the back frame 10 and is in a cantilever state. Alternatively, a portion of the back plate 11 below the apex portion 214 of the back frame 10 is overhanging. Accordingly, the lower portion of the back plate 11 is a lower exposed portion 11b (see FIGS. 1 and 27) that can be seen from the back. The lower exposed portion can be rephrased as an overhang portion.

Further, the side frame 13 of the back frame 10 is in a neutral state in which a seated person is not leaning, a portion above the vertex portion 214 is in a backward leaning posture, and a portion below the vertex portion 214 is in a forward leaning posture. ing.

(16). Back plate and back frame Next, the structure of the back plate 11 and the back frame 10 will be described. As described above, the backrest 4 has the back plate 11 and the mesh-shaped skin material 12. The attachment structure of the mesh skin material 12 will be described after the structure of the back plate 11 and the back frame 10 is described.

The back plate 11 is a molded product made of a synthetic resin such as polypropylene, and includes left and right side members 216 that are vertically long, an upper member 217 that is integrally connected between the upper ends of the side members 216, and left and right side members 216. The lower member 218 integrally connected to the lower end of the member forms a substantially rectangular outer shape. In addition, horizontally long support plates 219 connected to the left and right side members 216 are arranged in multiple stages.

Therefore, the back plate 11 has an appearance in which the horizontally long holes are formed in multiple stages. The horizontally long support plates 219 adjacent to each other are connected by narrow connecting pieces, and the left and right side portions of the horizontally long support plate 219 are provided with rearward facing ribs.

For example, as shown in FIG. 30, the side frame 13 of the back frame 10 has a groove shape opened forward. Therefore, a longitudinal groove 220 extending over the entire length is formed in a portion where the back plate 11 overlaps. As shown in FIG. 28, the support part which overlaps with the upper member 217 of the back board 11 among the upper frames 14 is also a groove shape with a forward opening. On the other hand, each member 216, 217, 218 of the back plate 11 has a groove shape opened rearward.

As shown in FIG. 37, the side frame 13 and the side member 216 overlap each other. The back portion 221 of the side frame 13 is gently curved so as to protrude forward as it goes outward in plan view, and an elongated wall 220 is formed by providing an inner wall 222 and an outer wall 223 thereon.

The back portion 221 of the side frame 13 protrudes inward from the inner wall 222. The side member 216 of the back plate 11 is gently curved in a forward concave shape, and by forming an inward rib 224 extending toward the inner wall 222 of the side frame 13, a shallow groove opened rearward is formed. Yes.

The inner wall 222 of the side frame 13 and the inward rib 224 of the side member 216 are formed with inner step portions 225 that mesh with each other. Thus, the back plate 11 is held so that it cannot be displaced inward by the inner step portions 225 meshing with each other.

The outer wall 223 of the side frame 13 has a narrow rib-like tip and is formed to be shifted inward from the outer end of the back portion 222. Therefore, an outer step 226 is formed on the outer portion of the outer wall 223. Is formed. Some space is provided between the outer wall 223 of the side frame 13 and the side member 216 of the back plate 11.

For example, as shown in FIG. 28, on the inner surface of the side member 216 in the back plate 11, three plate-like male fitting portions 227 that are vertically long and long apart are formed. On the other hand, in the vertically long groove 220 of the side frame 13, three pairs of female fitting portions 228 made of two ribs sandwiching the male fitting portion 27 of the back plate 11 from the left and right are formed. A female fitting portion 228 may be formed on the side member 216, and a male fitting portion 227 may be formed on the side frame 13.

The male and female fitting parts 227 and 228 are fitted to each other, so that the back plate 11 is held so as not to be laterally displaced with respect to the back frame 10. For this reason, the side member 216 does not move inwardly with respect to the side frame 13 at the time of locking, and the side frame 13 and the side member 216 are in an integrated state, and the entire backrest 4 is Increases rigidity.

As shown in FIGS. 28 and 29, in the groove of the side member 216 in the back plate 11, two first hooking hooks 230 are formed so as to be separated downward in a side view. On the side frame 13 of the frame 10, two upward hook-shaped second engagement claws 231 that mesh with the first engagement claws 230 are formed apart from each other in the vertical direction. The back plate 11 is held so as not to move forward with respect to the back frame 10 by the engagement of the engaging claws 230 and 23 1. Moreover, resistance to an external force that acts to twist in a plan view is also given.

For example, as shown in FIG. 29, a partition plate 232 is formed at the apex 214 of the side frame 13, and the longitudinal groove 220 is vertically divided by the partition plate 232. A lower guide part 233 is formed on the inner surface of the longitudinal groove 220 immediately above the partition plate 232, and the lower guide part 233 is inclined forward as the upper surface 233a goes upward in a side view. members 216, to form a lower projection 234 enters between the lower guide portion 233 and the inner wall 222, the lower protrusion 234 is provided with a lateral stopper 234a that overlaps the inclined surface of the lower guide portion 233.

By tilting the back plate 11 forward so that the upper part of the back plate 11 is separated from the back frame 10, the lateral stopper 234 a can be fitted into the fulcrum part inside the lower guide part 233. The side member 216 is provided with a lower positioning protrusion 235 that extends upward while being connected to the lower protrusion 234.

For example, as shown in FIGS. 29 to 31, the side member 216 of the back plate 11 is formed with a plurality of bosses 236 protruding rearward for attaching a skin material at appropriate intervals in the vertical direction. The boss 236 is formed in a trapezoidal shape whose outer diameter decreases toward the tip. On the other hand, a receiving portion 237 with which the boss 236 of the side member 216 abuts is formed in the longitudinal groove 220 of the side frame 13 (see also FIG. 37B).

Therefore, the boss 236 and the receiving portion 237 also serve as stoppers that restrict the front-rear position of the side frame 13 and the side member 216. As shown in FIG. 35, the boss portion 236 is also formed in the corner portion of the back plate 11 where the side member 216 and the upper member 217 are connected.

[Correction based on Rule 91 09.08.2010]
For example, as can be easily understood from FIG. 28, in the back frame 10, the longitudinal grooves 220 of the side member 13 are continuous with the lateral grooves 238 formed on the left and right sides of the upper frame 14. The upper frame 14 is formed with a pressing portion 239 that defines the left and right ends of the upper space 213, and a laterally long groove 238 is opened outside the pressing portion 239. The holding portion 239 is formed with a forward-facing auxiliary rib 240, and further, an upper engagement piece 241 that is continuous with the inner wall 222 of the side frame 13 is formed on the auxiliary rib 240, and the upper engagement piece 241 is associated with the upper engagement piece 241. The joint hole 242 is vacant.

On the other hand, the upper member 217 of the back plate 11 is formed with an upper engagement claw 243 that fits and engages with the upper engagement hole 242 of the upper frame 14 from above. Further, a side partition plate 244 is formed inside the upper engagement claw 243 in the upper member 217. The side partition plate 244 is set so as to be placed on the outer end portion of the auxiliary rib 240 in the upper frame 14. The side partition plate 244 is provided with a flange piece 244 a located above the upper engagement claw 243.

As shown in FIG. 34 (B) and FIG. 36 (A), the front surface of the upper member 217 in the back plate 11 is curved so as to shift back toward the top, on the back of the upper member 217, 3 The upper lateral groove 245 and the lower lateral groove 246 are formed by forming stepped ribs. As clearly shown in FIG. 32, the upper and lower lateral grooves 245 and 246 are formed between the left and right side partition plates 244.

For example, as can be inferred from FIG. 28, the side partition plate 244 of the upper member 217 is located on the outer surface of the pressing portion 239 in the upper frame 14. Therefore, as shown in FIG. 39B, the left and right ends of the upper and lower horizontal grooves 245 and 246 in the upper member 217 are positioned in front of the pressing portion 239.

As shown in FIG. 34C, the lower member 218 of the back plate 11 has a cross-sectional shape opened rearward. In addition, a lower engagement hole 247 opened in the front-rear direction is formed in the left and right intermediate part and the left and right side parts, and a lower protrusion 248 is provided to project upward at the position of the engagement hole 247.

As shown in FIG. 33, a long groove 220 is also formed in a portion of the side member 216 on the back plate 11 below the lower protrusion 234 (that is, the exposed portion 216a of the side member 216). An inward saddle-shaped saddle-shaped boss 250 projects from the long groove 220. A plurality of support ribs 251 having the same height as the inner stepped portion 222 are formed in the long groove 220 of the exposed portion 216a at appropriate intervals.

The attachment of the back plate 11 is performed according to the following procedure. That is, as can be understood from FIG. 29, first, with the back plate 11 tilted forward, the lower protrusion 234 is fitted on the lower guide portion 233 of the side frame 13, and the lateral stopper 234a is moved by shifting downward as it is. It touches against the inclined surface of the lower guide part 233. As a result, the back plate 11 is held so as not to be laterally displaced relative to the back frame 10.

Next, the back plate 11 is tilted backward with the lower end portion as a fulcrum, and slightly lifted and pressed against the back frame 10, thereby fitting the male and female fitting portions 227 and 228 together. Then, the first engagement claw 230 and the second engagement claw 231 are engaged with each other by shifting the back plate 11 downward.

The first engaging claw 230 and the second engaging claw 231 are engaged with each other with the upper end of the back plate 11 raised slightly forward until the engaging pieces 230 and 231 are completely engaged with each other. The front end of the upper plate 14 abuts against the upper surface plate 14 a of the upper frame 14 against the elasticity.

When the first engagement claw 230 and the second engagement claw 231 completely engage with each other, the upper engagement claw 243 is fitted into the upper engagement hole 242 and the stopper piece 244a is formed on the upper surface plate 14a of the upper frame 14. It enters downward (it fits in the horizontally long groove 238), so that the back plate 11 is held so that it cannot be displaced vertically and horizontally and back and forth with respect to the back frame 10. In this way, the back plate 11 can be attached to the back frame 10 by a very simple procedure.

In addition, after setting the lower guide portion 233 of the back plate 11 to the side frame 13, the back plate 11 is pushed forward with the lower end of the back plate 11 as a fulcrum, thereby pressing the back plate 11 into the back frame 10, thereby engaging. It is also possible to engage the claws 230 and 231. The distal end surface of the first engagement claw 230 and the a distal end surface of the second engagement claw 231, reference numeral 230a in an inclined surface is formed are (inclined surface 30 as meshing with each other are invited, at 231a It is shown.). When this method is adopted, the assembly becomes easier.

(17). Attachment Structure of Mesh Surface Material 12 Next, the attachment structure of the mesh surface material 12 will be described. The mesh-like skin material 12 is attached to the upper member 17 by a tape piece fixed to the outer periphery thereof. That is, as shown in FIGS. 34 and 35, the mesh-shaped skin material 12 includes a first side tape piece 253 that overlaps a portion of the side member 216 above the exposed portion 216 a from the back, and an exposed portion 216 a of the side member 216. A second side tape piece 254 that overlaps from the back side, a corner tape piece 255 that overlaps the upper corner of the back plate 11 from the back side, and an upper tape piece 256 that overlaps the upper member 217 between the corner tape pieces 255 from the back side, A lower tape piece 257 that overlaps the lower member 218 of the back plate 11 from the back is fixed by adhesion or adhesion. The tape piece is an example of an edge member.

Each tape piece uses a resin sheet such as a polypropylene sheet, but other materials can also be used. The corner tape piece 255 can be integrally connected to the first side tape piece 253.

The first side to the tape strip 254 and first mounting hole 258 fits to the boss 236 of the side member 216 is formed, as shown in FIG. 37 (B), the first side piece of tape 254 side members 216 from the outside And the side frame 13 and is fitted into the boss 236. The first side tape piece 254 faces the side member 216, so that only the mesh skin 12 can be seen from the outside. Further, the outer skin 223 of the upper frame 14 is in contact with the mesh-shaped skin material 12, so that the inside of the side frame 13 (vertically long groove 220) cannot be seen from the outside. For this reason, it is excellent in aesthetics.

As shown in FIGS. 34 and 35, the first side tape piece 253 is formed with a notch 259 so as not to obstruct the connecting portion between the side frame 13 and the side member 216.

The second side tape piece 254 has a belt-like shape with no notch. As shown in FIG. 33 partially, the exposed portion 216a of the side member 216 of the back plate 11 has an inner step 216c and An outer step portion 216d is formed, and the second side tape piece 254 is fitted in a space between the inner step portion 216c and the outer step portion 216d, and is thus held in a non-displaceable direction in the width direction. ing. The second side edge member 254 also has a mounting hole 258 that is fitted into the hooked boss 250.

In addition, the second side tape piece 254 also has a mounting hole 258, which is fitted into the bowl-shaped boss 250. Since the hook-shaped boss 250 has an inward hook shape, the second side tape piece 254 does not come off. The second side tape piece 254 also overlaps the side member 216 and cannot be visually recognized from the outside.

The corner tape piece 255 is also held in the boss 236 so that it cannot be removed. Corner tape piece 253 has a convex curved profile obliquely outward to fit the corner of the back plate 11, the corner piece of tape 255 in FIG. 35 (A) is displayed on the position of the inwardly convex. When it is folded back and attached to the back plate 11, it becomes an outwardly convex posture. The inner end portion of the corner tape piece 255 is narrow, and is disposed on the upper side of the stopper piece 244a connected to the side partition plate 244 as shown in FIG.

As shown in FIG. 36 (A), the upper tape piece 256 is fitted into the upper horizontal groove 245 of the upper member 217 from behind. Therefore, the upper tape piece 256 is not exposed to the outside. The left and right ends of the upper tape piece 256 extend to the side partition plate 244 (see FIG. 31). As shown in FIG. 36 (B), the left and right ends of the upper tape piece 256 are held so as not to move backward by stopper ribs 210 provided on the upper frame 14. For this reason, even if the upper tape piece 256 is only fitted in the upper horizontal groove 245, it is held so that it cannot be removed.

As shown in FIG. 36 (A), Roatepu piece 257 is fitted from behind the lower member 18, at three locations of the left and right intermediate portions and the right and left sides, fitted under engaging hole 47 of the lower member 18 A hook-shaped engagement claw 261 is formed, and the engagement claw 261 is hooked on the lower protrusion 248 of the engagement hole 247 from the front. As a result, the lower tape piece 256 is held by the lower member 18 so as not to be detached.

Mounting mesh-like skin material 12 to the back plate 11, first, the left and right side tape piece 253 is attached, then fitted with a Roatepu piece 257, and finally attaching the upper tape piece 256, the procedure referred Done. The back plate 11 on which the mesh-like skin material 12 is thus mounted is attached to the back frame 10. At the time of attachment to the back frame 10, the peripheral edge portion of the mesh-like skin material 12 abuts on the back frame 10 and slightly deforms.

(18). Cushion material mounting structure The back plate 11 can be provided with a cushion material. This point is shown in FIGS. The cushion material 263 is accommodated in a bag body 266 having front and back sheets 264 and 265 made of cloth or the like. The bag body 266 is an example of a skin material.

As can be understood from FIG. 38, the bag body 66 basically opens upward, and the left and right side portions are also cut open at the portion above the apex portion 214 (see FIG. 1B) of the back frame 10. Yes. Further, a cushion material 263 is stretched on the front surface of the back plate 11, and both are covered with the bag body 266. Therefore, the back sheet 265 is located on the back side of the back plate 11, and the back plate 11 cannot be visually recognized from the back side (it can be seen through).

Then, the first side tape piece 253 is attached to the side edge of the front sheet 264 and the side edge of the back sheet 265, the corner tape piece 255 is attached to the corner portion of the back sheet 265, and the upper edge of the front and back sheets 264, 265 is upper. A tape piece 256 is attached. A corner tape piece 255 is not attached to the upper sheet 265 (it can be attached).

40, the first side tape piece 253 of the front sheet 264 is fitted to the boss 236 in the same manner as in the case of the mesh-like skin material 12. On the other hand, the first side tape piece 253 of the back sheet 265 is disposed on the back side of the side member 216 from the inside and is fitted to the boss 236. Therefore, the side portion of the back sheet 265 is sandwiched between the inner wall 222 of the side frame 13 and the inner rib 214 of the side member 216.

As shown in FIG. 39, the upper tape piece 256 fixed to the front sheet 64 is fitted in the upper horizontal groove 245 as in the case of the mesh-shaped skin material 12, while the upper tape piece 256 fixed to the back sheet 265. Is fitted into the lower lateral groove 246 from behind. The left and right ends of the upper and lower upper tape pieces 256 are held by the pressing portion 239 of the upper frame 14 so as not to move backward. The corner tape pieces 255 are arranged in the same manner as the mesh skin material 12. Since the exposed portion 11b of the back plate 11 is completely covered with the bag body 266, no attachment means such as a tape piece is necessary.

As shown in FIG. 40, when the cushion material 263 is turned to the side edge of the side member 216, the edge portion of the cushion material 263 can enter the outer step portion 226 of the side frame 13. For this reason, the edge part of the cushioning material 263 can be treated beautifully, and the aesthetics can be improved.

(19). Advantages of the backrest embodiment (a)
As for the back of the chair, a lumbar support function that accurately supports the lumbar part of the seated person is emphasized. As part of this, Japanese Patent Publication No. 2008-183356 has a back plate attached to the back support. In the chair, the upper part of the back plate above the lumbar support part is fixed to the back support, and the lower part of the back plate including the lumbar support part is a movable part that can be rotated back and forth around its upper end. It is disclosed that the lower part of the back plate is pivoted forward relative to the upper part at the time of locking.

The above publication is intended to enhance the body support function at the time of rocking, but when the lower part of the back plate (back) is forcibly advanced relative to the upper part at the time of rocking, the seated person will feel a strong sense of pressure on the waist. There is. Therefore, it can be said that it is preferable that the backrest bends and deforms so that the lumbar support portion is retracted by the body pressure of the seated person from the viewpoint of cushioning and fit.

This embodiment addresses such a current situation. That is, the present embodiment is intended to provide a chair with a simple structure that exhibits a lumbar support function accurately and is excellent in cushioning and fitting properties. Generalizing this configuration is as follows.

A back plate for receiving the body pressure of the occupant, has a back support that the back plate is Toritsui, waist or portion corresponding to a peripheral portion of the seated person of the back plate lumbar support portion protruding earliest The back plate has a portion above the lumbar support portion attached to the back support, and the lower portion of the back plate including the lumbar support portion is formed from the back support to the cantilever. In the state, it is an overhang portion projecting downward, and the overhang portion can be bent and deformed by the body pressure of the seated person.

Furthermore, this configuration (first configuration) can be expanded as the second configuration as follows. The back plate is a molded product of a synthetic resin, and includes left and right side members and a group of horizontally long support plates arranged between them, and the overhang portion of the back plate is The constituent side members can be bent and deformed by the body pressure of the seated person, and the horizontally long support plate can be bent and deformed so as to move backward by the body pressure of the seated person. The strength is set so that the horizontally long support plate is easily bent and deformed.

According to the above configuration, the backrest, since the overhang portion including a lumbar support portion can be deformed by body pressure of a seated person, applying a reaction force of moderate relative seated person's waist (or its periphery) Therefore, cushioning and fit can be improved.

In particular, according to the second configuration, the overhang portion of the back plate is high due to the deformation of the horizontal support plate and the deformation of the side member, in addition to ensuring the fit to the body by the deformation of the horizontal support plate. Cushioning properties are ensured, which is particularly suitable. Further, since the horizontally long support plate can be bent and deformed even in the non-locking state, it is also excellent in that the fitting property can be improved in the non-locking state.

(20). Advantages of the backrest embodiment (b)
As a backrest of a chair, there is a structure in which a back plate is attached to the back frame as a configuration having a back frame as a strength member constituting the outer peripheral portion and a back plate arranged in front of the back frame. One example is disclosed in Japanese Patent Publication No. 2008-119220.

That is, in this publication, the back plate is disposed with a space between it and the back frame (backrest frame), and a shaft portion protruding upward is integrally provided on the front surface of the left and right vertical frames in the back frame. The left and right side portions of the back plate are provided with female engaging portions that fit into the shaft portion of the vertical frame from above. In the above publication, a large number of vertically long slits are formed in the back plate. Therefore, the back plate is allowed to stretch and deform due to the body pressure of the seated person. That is, the back plate is stretched and deformed to ensure cushioning.

Backrest design may vary, but it is also one design idea of spaced in front of the back frame body pressure support as above publication, the body pressure support are overlapped on the back frame appearance Many people like it. That is, there is also a demand for a configuration in which the body pressure support and the back frame are overlapped and connected to each other. Therefore, such a request cannot be satisfied by the configuration in which the shaft portion and the engaging portion are exposed as in the above publication.

In the above publication, the back plate hardly functions as a strength member, and the role of the strength member is exclusively played by the back frame. For this reason, in order to increase the rigidity of the back frame, it is necessary to take measures such as increasing the thickness or making it by die casting aluminum, and there is a concern that the cost increases.

This embodiment deals with the current situation as described above, and provides a backrest having a body pressure support attached to a back frame in a more improved form. The invention relating to this point can be generalized as follows.

It has a back frame as a strength member that constitutes the outer periphery of the backrest, and a body pressure support that overlaps the back frame from the front, and the back frame has a long groove that opens forward in the longitudinal direction. Engagement means for attaching the body pressure support to the back frame is provided on the back surface of the body pressure support and the inside of the long groove in the back frame. It should be noted that the whole body of the body pressure support may overlap the back frame or may partially overlap.

As a development example of the present invention, in the second configuration, the back frame has left and right side frames that are vertically long and long, and an upper frame that is connected to the upper end of the back frame. Is provided.

In the above configuration, the body pressure support body and the back frame are externally provided by providing the engagement means in the long groove formed in the back frame while the body pressure support body (for example, the back plate) is superimposed on the back frame. Can be connected invisible. For this reason, it is possible to easily realize a backrest with a refreshing design in which the body pressure support is superimposed on the back frame. In the embodiment, the first engagement claw 230 and the second engagement claw 231 mainly serve as engagement means.

(twenty one). Advantages of the backrest embodiment (c)
In many cases, only the skin material is applied to the back plate for the purpose of makeup, or the skin material is applied through a cushion material. In any case, the skin must be attached to the backplate in a state that does not come off or shift. Therefore, if the skin material is attached to the above publication (Patent Publication No. 2008-119220), the entire back plate is exposed at the back in the above publication, so the entire attachment portion of the skin material is also exposed. . Therefore, there is a problem that it is troublesome to prevent the aesthetics from deteriorating.

This embodiment also addresses this point. This is generalized as follows.

A back frame that constitutes the outer periphery of the backrest and functions as a strength member; and a body pressure support disposed on the front side of the back frame, and at least the entire left and right side portions of the body pressure support Alternatively, in a backrest that a part of the backrest overlaps the back frame from the front, the front surface of the body pressure support is covered directly with a skin material or covered with a skin material through a cushion material, and the body pressure An attachment portion for the skin material is provided at least in a portion of the support that is hidden by overlapping the back frame.

The above configuration (first configuration) can be developed in various ways. In the second configuration as an example, the peripheral edge of the skin material extends on the back side so as to embrace the front of the body pressure support, the peripheral edge of the skin material is attached to a tape-shaped edge member, the edge member It is hooked on locking means provided on the back side of the body pressure support. In the embodiment, the boss 236 mainly functions as locking means.

In the above configuration, the skin material mounting portion provided at the overlapping portion with the back frame of the body pressure support body is not exposed to the outside, so that the skin material mounting portion at the overlapping portion is maintained in strength without considering aesthetics, etc. Therefore, it is possible to securely and easily attach the skin material to the body pressure support body while ensuring aesthetics.

As a means for attaching the skin material to the body pressure support body, for example, various structures such as bonding screws can be adopted. However, when a tape-like seating member is used as in the second configuration, the attachment to the body pressure support body is not possible. Since only the member needs to be hooked on the locking portion, there is an advantage that the skin material can be efficiently attached.

(22). Others The present invention can be embodied in various ways other than the above embodiment. The chair to be applied is not limited to a swivel chair, but can be applied to a non-lifting chair such as a conference chair or a fixed chair such as a theater chair.

Further, the back plate may be a simple plate shape (shell shape). The body pressure support that constitutes the backrest does not necessarily need to be a back plate. For example, a structure in which a mesh-like support sheet is stretched on a frame material that is open at the front and back may be used.

The utility of the present invention chair is demonstrated. Therefore, it can be used industrially.

1 Leg support (gas cylinder)
2 Base 2c Front wall 2d Base forward flange 3 Seat body 4 Backrest 7 Seat receiver 8 Seat portion 10 Back frame 16 Forward arm portion constituting a part of the back support device 18 Swing member constituting the back support device 19 A first shaft that is a pivot for pivoting a backrest 20 A rear pin as an example of a rear pin 21 A rear engaging claw as an example of a seat receiving body of a seat receiving body 22 A second shaft that is a front shaft 23 A front link 24 of a seat receiving body Upper female fitting portion constituting the front connecting portion 25 Base upper cover 26 Base lower cover 45, 53 Rubber as an example of elastic means 78 Front link lower inner female fitting portion 79 Front link lower side female Form fitting part 84 Restriction rib 86 Boss part of front link

Claims (6)

1. A base provided at the upper end of the leg, a seat disposed above the base, a back support device connected to the base so as to be tiltable backward, a backrest provided on the back support device, and a back tilt of the back support device and the backrest Elastic means for imparting resistance to the front surface, the lower surface of the seat portion is connected to the base via a front link, and a front side of the back support device before the rotation fulcrum. A rear connecting part connected to the part of the chair, and when the backrest tilts backward, the seat part moves up and retreats,
   By adopting a form in which the front connecting part and the rear connecting part of the seat part protrude downward, a space that does not pinch even when a person inserts a finger between the seat part and the base is made available.
   Rocking chair.
2. At least one of the following three connections: a connection between the front connection portion of the seat portion and the front link, a connection between the front link and the base, and a connection between the rear connection portion of the seat portion and the back support device. Is a method of fitting by moving the seat part or the front link relative to each other in a direction orthogonal to the rotational axis of the back support device.
   The rocking chair according to claim 1.
3. The base has a box shape with an upward opening having a front wall at the front end, and a left and right horizontally long front support shaft on which the front link is rotatably fitted is disposed at the front portion of the base, The front link is formed with a space in which the front plate of the base fits, and a space formed by the front inner surface of the space and the front wall of the base is enough to insert a human finger. Is set to a size, and forms a forward-facing flange at the upper end of the front wall of the base,
   The rocking chair according to claim 1 or 2.
4. The rear connecting portion of the base and the back support device are connected by a rear pin, and an upper cover having a receiving portion for the rear pin is attached to the base, and an upward wall surrounding the rear pin is formed on the upper cover. On the other hand, a downward projecting wall that surrounds the upper cover from the outside is formed on the lower surface of the seat portion, and a narrow space between which the person cannot insert a finger between the upward projecting wall and the downward projecting wall There is only a gap between
   The rocking chair according to claim 1.
5. While the base has a box shape opened upward, the front link is only one and is disposed at the left and right middle part of the seat part,
   The rocking chair according to claim 1 or 2.
6. The elastic means is rubber, and the rubber is disposed in the vicinity of the rotation fulcrum of the back support device.
   The rocking chair according to claim 1 or 2.

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