WO2017082316A1 - Chair - Google Patents

Abstract

A backrest 3 is composed of nine elements a-f sectioned vertically and horizontally. An upper-level center element a and a middle-level center element b are connected so as to be able to turn relative to each other, and other adjacent elements are connected so as to be able to turn relative to each other. In a working posture in which a person's body is substantially vertical, the person's hips contact the boundary portion of the middle-level center element b and a lower-level center element c, and side elements d, e, and f turn so as to surround a person sitting. In a rocking state, the middle-level center element b and the lower-level center element c deform toward a flat posture, and the side elements d, e, and f turn so as to widen toward the outer sides.

Description

Chair

The present invention relates to a chair.

For example, in a swivel chair frequently used in offices, the backrest is generally loosely dented on the front surface (body pressure support surface) according to the human body. In general, the backrest remains in a preset shape, whether it is in a neutral state where the user's body is not hit or in a rocking state where the user's body pressure is tilted backward. In most cases, the shape itself remains constant.

However, in the state where the body is upright and the rocking state where the body is tilted backward, the way the body touches the backrest is different, and the role that the user requires for the backrest is also different, so depending on the posture of the user It is reasonable to change the shape of the backrest so that a suitable support mode is realized. Chairs developed from such a viewpoint are disclosed in Patent Documents 1 and 2 (both have the same contents).

When Patent Documents 1 and 2 are described based on the illustrated embodiment (first embodiment), the backrest is divided into a center area and a left and right side area in the left-right direction, and the center area and the side area Are divided into upper, middle, and lower three-stage elements, and therefore the backrest is composed of nine elements (parts) as a whole. Adjacent elements are connected via hinges so that they can rotate relative to each other.

Further, in Patent Documents 1 and 2, by setting each element to a trapezoidal or inverted trapezoidal shape (or a triangle or an inverted triangle), adjacent elements are made continuous. As a result, nine elements are obtained. A single backrest is constructed in combination. In addition, the front surface of the center area and the front surface of the side area are arranged in a bending posture so that the depression angle is an obtuse angle in plan view, thereby ensuring a body wrapping function (fit function).

Also, in a side view, the middle element and the lower element are set in a posture that forms a convex convex chevron shape. For this reason, the lumbar support part which supports a user's lumbar part is comprised by the middle stage element and lower stage element of the center area. In contrast, the middle element and the upper element are bent at an obtuse angle close to a straight line so as to be concave forward (to be convex backward).

And when the chairs of Patent Documents 1 and 2 are locked, the relative position of the middle element and the lower element changes so that the depression angle formed by them increases (so as to spread), and accordingly, The side area rotates relatively rearward with respect to the center area. That is, the side area escapes and rotates in a direction away from the user's body.

International Publication WO2013 / 164078 Special table 2015-519111 gazette

In Patent Documents 1 and 2, the shape of the backrest (three-dimensional shape) changes following the change in the posture of the user, and therefore the body is supported in a suitable state in both the working state and the locking state. You can do it.

The main purpose of the present invention is to suitably develop the inventions presented in Patent Documents 1 and 2. That is, the main purpose is to improve the functions realized in Patent Documents 1 and 2. In addition, the present application discloses many improved configurations for each part of the chair, but these improved configurations can be the subject of patents as independent inventions that can be applied to various chairs. is there.

The present invention has various configurations. That is, the present application is composed of a number of inventions below the first invention.

A lockable backrest has a center area located in the middle in the left-right direction when viewed from the front, and side areas arranged on both the left and right sides of the center area, the side area being relative to the center area And can be bent in the longitudinal direction.
A state in which the seater's load is not applied to the backrest at all is a neutral state,
In the working state where only the lumbar part of the seated person hits the center area, the left and right side areas bend in the direction of wrapping the seated person from the neutral,
When the seat occupant puts his back against the center area and the backrest locks, the left and right side areas bend in a direction away from the seat occupant based on the neutral state.
It is set to make a movement.

The chair of the second invention is a development example of the first invention. In the first invention, first,
“The center area has a middle center element located above the waist of the seated person and a lower center element located below the middle center element. The middle center element and the lower center element Thus, a mountain-shaped configuration is formed toward the waist of the seated person, and the middle center element and the lower center element are relatively rotatable so that the depression angle changes. ''
It has a basic configuration.

In the basic configuration, when the neutral state is shifted to the office state, the side center element and the lower center element are pushed by the waist of the seated person, and the depression angle formed by the two is increased. The area is set to bend in the direction of wrapping the seated person.

The third invention is also a development example of the first invention, and under the same premise configuration as the second invention, in a locking state, in conjunction with a decrease in the included angle between the middle center element and the lower center element, The side area is configured to spread and deform in a direction away from the seated person.

The fourth invention is structurally characterized by the second or third invention. That is, in the fourth aspect of the invention, the backrest is first connected to a back column so that the backrest can be rotated in the front-rear direction with a portion positioned above the waist of the seated person as a rotation fulcrum. An elastic body that is elastically deformed by a change in the relative angle between the backrest and the back column is disposed between the portion below the pivot point and the back column.

Further, in the fourth aspect, the neutral state of the backrest is maintained by being in a reference state in which the elastic body is hardly or not deformed in the neutral state.
When the backrest shifts from the neutral state to the working state, the elastic body is deformed in one direction from the reference state, and the included angle formed by the middle center element and the lower center element is increased, and each side is interlocked with this. While the area bends to reduce the included angle with the center element,
If the body pressure of the seated person is strongly applied to the portion above the pivot point in the locked state, the elastic body is deformed in the other direction from the reference state, and the middle center element and the lower center element are formed. The depression angle is decreased, and the side areas are bent so as to increase the depression angle with the center element.

The fifth invention is a development example of the second or third invention, and in this invention, the deformation of the elastic body includes a deformation in which expansion and contraction deformation and bending deformation are combined. In addition to or instead of claim 5, twisting deformation may be included.

The sixth invention is an invention independent of the first invention. The chair of this sixth invention is
The lockable backrest has a center area located in the middle in the left-right direction when viewed from the front, and side areas arranged on the left and right sides of the center area,
While the center area is composed of a plurality of center elements that are vertically connected in a bent posture in a side view,
The side area is composed of a plurality of side elements that are vertically connected in a bent posture in a side view corresponding to the elements of the center area, and each element of the side area is in relation to the center area. In addition to being connected to bendable, the elements adjacent to each other in the vertical direction are also connected to bendable,
When the backrest is locked by the seated person's backrest, each element in the side area bends away from the seated person so as to widen the depression angle with the element in the center area.

The seventh invention is a preferred development of the first or sixth invention. That is, in this invention, in the first or sixth invention,
The center area and the side area are each composed of a three-stage element including a middle element, an upper element, and a lower element,
By arranging the middle center element and the lower center element in a forward convex posture in a side view, a protrusion that supports the lumbar portion of the seated person is formed,
The middle-stage center element and the lower-stage center element can be bent relatively, and the middle-stage center element is held so as not to be bent with respect to the upper-stage center element.

The eighth invention is independent of the first and sixth inventions. This invention
The backrest has a center area located in the middle in the left-right direction when viewed from the front, and side areas arranged on the left and right sides of the center area,
While the center area is composed of a plurality of elements connected in the vertical direction with a bent posture in side view,
The side area is composed of a plurality of elements connected in the vertical direction in a bent posture in a side view corresponding to the elements in the center area, and each element in the side area is bent with respect to the center area. Are connected to each other, and the elements adjacent to each other in the vertical direction are connected to each other so that they can be bent.
According to the movement of the seated person, each element of the side area has a configuration in which the posture changes in the direction of wrapping the seated person, or the posture changes in the direction away from the seated person,
Among the plurality of elements constituting the center area, at least two elements that are located above the waist of the seated person and are adjacent to each other in the vertical direction are non-bent elements that do not bend relatively. The element is connected to the non-bending element so that it can be bent.

A ninth invention is the eighth invention,
The center area and the side area are each composed of a three-stage element including a middle element, an upper element, and a lower element,
A lumbar support part that supports the lumbar part of the seating is formed by connecting the middle element and the lower element of the center area to a forwardly convex posture in a side view,
The middle element and the lower element in the center area are bendable, and the middle element and the upper element are continuous so as not to bend.

The tenth invention is the first invention, the sixth invention, the eighth invention,
The backrest includes a cushion material that extends over the entire surface of the backrest. A boundary portion between adjacent elements of the cushion material is partitioned by a groove, and the surface of each element is flat.

The eleventh aspect of the invention embodies the tenth aspect of the invention.
The seat has a seat cushion material that extends over the entire upper surface, and the cushion material is formed with a plurality of grooves that divide the cushion material into a plurality of elements in both the left-right direction and the front-rear direction. ,And,
The pattern of the element in the back cushion material and the element in the seat cushion material are in a form close to symmetry.

The twelfth invention is also a development example of the tenth invention, and in this invention,
A skin material is stretched on the surface of the back cushion material, and by fixing the skin material integrally to the back cushion material by insert molding, the skin material enters the inside of the groove and is stretched as a whole. Bonded to back cushion material.

The invention of claim 13 is also a development example of the tenth invention.
The backrest includes a back outer shell constituting the back surface and a back cushion material constituting the front surface, and a groove is formed on the back surface of the back outer shell symmetrically with the groove of the back cushion material. ing.

The 14th invention is also a development example of the 10th invention.
The groove has a substantially V-shaped, substantially U-shaped or substantially trapezoidal cross-section in which the distance between the bottoms is narrower than the distance between the opening edges, and the depth dimension is about half the thickness dimension of the back cushion material. Is set to

(1). Effect of the first invention When a person uses a chair, the function required of the chair differs depending on the use mode of the chair. For example, when working at a desk, such as operating a personal computer, a function that holds the upper body in an upright position is required from the viewpoint of reducing the burden on the body. In this regard, in the first invention, since the side area is deformed so as to hold the upper body of the seated person from the left and right, the stability of the body can be enhanced.

Now, when a person sits on a chair and takes an office posture in which the upper body is almost upright, the person is burdened with muscles and the like to stabilize the pelvis. In other words, in order to hold the upper body in an upright posture, the pelvis, the muscles that wrap it, and the lumbar spine are burdened. Therefore, without any support, human fatigue gradually increases.

And if you support the lumbar part from the back, the burden on the muscles and lumbar spine is reduced, but since the body tries to lean in the left and right direction, the muscles and lumbar spine also work to suppress the lateral collapse, Therefore, simply supporting the lower back from the back may make it difficult to reduce the burden on the body when the working state is continued for a long time.

In this regard, in the first invention, the seated person's lower back can be supported from the left and right directions, so the physical burden for holding the body from falling to the left and right can be reduced. As a result, the burden on the user's body can be remarkably reduced even when the working state is continued for a long time.

In addition, since the physiques of people vary, there may be cases where the side area hits or does not win in the office state. In this regard, even if the physique is small, even if the physique is small, the side area can be prevented from touching and touching the side area immediately if it is tilted to the left or right Is retained. Therefore, the value of the present invention is not reduced because the physique is small.

Designed based on the standard physique of adults, and set so that the side area lightly touches the lower back when a standard person is working, the difference in physique to some extent is the amount of rotation of the side area It can be said that it is realistic to absorb it. Of course, it is also possible to prepare a plurality of types of chairs corresponding to differences in physique.

On the other hand, in the rocking state, if the holdability by the backrest is too high, it may feel cramped. In this respect, in the first invention, the side area is expanded and deformed when rocking, and the backrest tends to be in a flat direction, so that the freedom of the upper body is increased and the comfort can be enhanced.

Thus, in the first invention, the mode of deformation of the backrest differs depending on the mode of use of the chair, and the function desired by the user can be provided. Therefore, the chair can be made excellent in the feeling of use.

(2). Concomitant Effects of the Second to Fifth Inventions In the second invention, the seated person's waist is supported by the convex portion formed of the middle center element and the lower center element, so that the effect of the first invention can be promoted and suitable. It is. In the third invention, the backrest can be changed to a suitable form in each of the working state and the locking state by changing the angle formed by the middle center element and the lower center element. Therefore, a simple structure can be used as a chair with excellent usability.

When the fourth invention is adopted, the structure can be simplified because the side area can be expanded and deformed by using the rotation of the backrest. This is a great advantage. In addition, the backrest can be held in the neutral state while allowing the elastic body to be deformed in two directions with the reference state sandwiched between the working state and the locking state. Therefore, it is possible to easily change the backrest into three states with a simple structure.

As in the fifth aspect of the invention, when the posture (tilt) of the backrest is controlled using the expansion and contraction and bending of the elastic body, the sag of the elastic body can be suppressed and the durability can be improved. In addition, since it is often easy to bend even with a relatively hard elastic body, even if the relative rotation angle between the backrest and the back column is large, the elastic body can be firmly followed and deformed. Therefore, the posture control function of the backrest is excellent.

(3). Effects of the sixth and seventh inventions The sixth invention is the one obtained by extracting the movement at the time of locking of the first invention, and it is possible to improve the comfort by improving the freedom of the body as described above. It is.

The center area and the side area can be divided into two upper and lower tiers, for example. In the case where the height of the backrest is small, such a division mode may be used. On the other hand, if the backrest is a high-back specification that hits the shoulder, for example, as in the seventh invention, the center area and the side area are divided into three stages, and the movement of the side area is smoothed. The support function can be improved.

(4) Effects of the eighth and ninth inventions In Patent Documents 1 and 2, the center area is configured in three stages, and the elements adjacent to each other in the vertical direction can be rotated relative to each other. In this aspect, it can be said that the fit to the body is high, but the stability of the body may be reduced. In this regard, in the eighth invention, the stability of the body can be improved by adopting a configuration in which the plurality of elements constituting the center area are not bent.

In particular, as in the ninth aspect of the invention, when the middle center element and the upper center element are set so as not to be bent, for example, the center area as a whole is allowed to change its side view posture, and has high body stability. There is an advantage that can be secured.

In other words, when the backrest is deformed excessively, for example, when the body is twisted to the left or right, the backrest is also deformed too much, so to speak, the body tends to be twisted excessively, so that the burden on the body is increased. However, if the middle center element and the upper center element have a rigid structure as in the ninth aspect of the invention, the body can be twisted without burden. Even if the body bends excessively backwards, the head may tilt too much and strain on the neck, or the abdominal muscles must be used to return to the original position. In the invention, it is possible to prevent the body from bending excessively backward. Also in this aspect, it has an excellent body comfort keeping function.

Furthermore, in the ninth invention, there is an advantage that reliability can be improved by preventing an excessive tension from being applied to the hinge portion connecting the upper side element and the middle side element.

(5). Effects after the tenth invention In the tenth invention, since the cushion material spreads in a series as a whole, the assembly of the backrest is easy and the dimensional accuracy is also improved. Further, since the surface of each element is flat, it is possible to give a favorable impression to a person without excessive decoration. That is, it can be refined in design. Moreover, since each element is flat, the body supporter hits the human body over a wide area, so that fit to the body can be improved.

Further, as described above, the groove has a cosmetic effect, but in the present invention, since the groove portion of the cushion material becomes a thinned hinge part, the ease of changing the shape of the body support and the cosmetic effect are improved. There are advantages that can be achieved at once. The groove has a cosmetic effect, but since this cosmetic effect is not necessarily integral with the hinge function, the feature of the tenth invention can be applied to a backrest or a seat where adjacent elements are not bent. That is, the tenth invention can be an independent invention as such.

When the eleventh invention is adopted, the backrest pattern and the seat pattern are unified in design, so that the high aesthetic effect of attracting people as a whole chair can be further improved.

Although the skin material is usually stretched on the surface of the cushion material, when the structure of the twelfth invention is adopted, the skin material can be bonded to the cushion material in a state of being in the groove and being stretched. Therefore, the effect of improving the design can be ensured. Further, since the surface area of the cushion material is increased due to the presence of the groove, there is also a technical effect that the adhesive strength of the skin material can be improved.

In the thirteenth invention, since the front and back of the backrest are unified, it can be said that the cosmetic effect can be enhanced and the product value can be further improved.

The pattern formed by the groove can be arbitrarily set. However, when the geometric pattern is employed as in the embodiment, the groove may be directly, and thus there is an advantage that the mold for molding the cushion material can be easily processed. Further, when the fourteenth invention is adopted, the groove is in a state where the eyes are open, so that the visibility is high and the eye-catching cosmetic effect is excellent. Further, when a groove is machined using a mold as in insert molding, it is easy to mold, so that molding is easy.

It is a figure which shows the external appearance of the chair which concerns on embodiment, (A) is the whole perspective view seen from the front, (B) is a top view, (C) is the perspective view seen from back. It is a figure which shows the external appearance of the chair which concerns on embodiment, (A) is a front view, (B) is a rear view, (C) is a side view, (D) is a front view of only a backrest. It is a figure which shows the motion of a backrest, (A) is a side view which shows the transition to a non-locking state, (B) is a side view which shows the transition to a locking state, (C) is a top view which described each state together . It is the isolation | separation perspective view which mainly displayed the seat part and the base part. (A) is the isolation | separation perspective view of a lower stage center element and a rear seat outer shell, (B) is a perspective view of the state which connected the lower stage center element and the rear seat outer shell. It is a figure which shows a backrest, (A) is the perspective view which showed the back outer shell, (B) is the perspective view which abbreviate | omitted the back outer shell. (A) is the isolation | separation perspective view of a backrest, (B) is the perspective view which looked at the back cushion material from back. It is a separate perspective view of the component of a backrest. (A) is the perspective view which looked at the back inner frame from back, (B) is the partial perspective view which looked at the back inner frame from the lower part, (B) is the partial side view of a back inner frame. (A) is the perspective view which shows the relationship between a back support | pillar and a back outer shell, (B) is the partial perspective view which looked at the back outer shell from the downward direction. It is a figure which shows the relationship between a back support | pillar and a back outer shell, (A) is the whole isolation | separation perspective view, (B) is a perspective view which shows the relationship between a back support | pillar and a pressing member. It is a figure which shows the relationship between a back support | pillar and a back outer shell, (A) is the XIIA-XIIA partial sectional view of FIG. 2 (A), and (B) is a vertical side view in the fastening part of a pressing member. 2A is a cross-sectional view taken along line XIIIA-XIIIA in FIG. 2A, FIG. 2B is a cross-sectional view taken along line XIIIB-XIIIB in FIG. 2A, and FIGS. It is principal part sectional drawing which shows the example of a method. (A) is a partial perspective view of the backrest with the cushion omitted, and (B) is a partial perspective view of the outer shell. (A) is a partial perspective view of the backrest in a state where the cushion is omitted, and (B) is a partial perspective view of the back outer shell. (A) is a cross-sectional view of the backrest as seen from the position XVIA-XVIA in FIG. 9, (B) (C) is a perspective view of the clip, (D) is a cross-sectional view showing the procedure for attaching the back inner frame to the back outer shell It is. (A) is an isolation | separation perspective view which shows the attachment structure of a back support frame, (B) is an isolation | separation perspective view which shows the relationship between a tilting base and a fixed base. (A) is a separated perspective view showing the relationship between the seat support member and the tilt base, (B) is a diagram showing the movement of the tilt frame and the back support frame. (A) is an exploded perspective view of the base portion, and (B) is a perspective view of the base portion and the seat from below. It is a center part vertical side view of a seat part. (A) is the isolation | separation perspective view of the seat cushion and seat inner shell which comprise a seat, (B) is the elements on larger scale of a seat inner shell. (A) is the isolation | separation perspective view of a seat part, (B) is the elements on larger scale of the main outer shell. (A) is a separated perspective view of a seat inner shell and a seat outer shell, (B) is a partially enlarged perspective view of a rear end portion of the seat inner shell, and (C) is a partially enlarged perspective view of a rear portion of the seat outer shell. . It is the isolation | separation top view which arranged the seat inner shell and the seat outer shell side by side. (A) is the isolation | separation perspective view of a front outer shell and an intermediate | middle outer shell, (B) is the perspective view seen from the bottom in the state which mounted | wore the intermediate | middle outer shell with the front outer shell. It is sectional drawing of the seat in the XXVI-XXVI viewing location of FIG. It is a schematic diagram which shows another example of the pattern and pattern of the surface of a backrest and a seat.

Next, an embodiment of the present invention will be described with reference to the drawings. This embodiment is applied to a swivel chair often used for offices. In the following explanation, front / rear / left / right words are used to specify the direction, which is defined as a state viewed from a person who normally sits on a chair. The front view is a state seen from the direction facing the seated person.

(1). Outline of Chair First, an outline of the chair will be described with reference to FIGS. The basic configuration of the chair is the same as that of the prior art, and as shown in FIGS. 1 and 2, a leg device 1, a seat 2, and a backrest 3 are provided as main components. Moreover, the armrest device 4, the hanger 5, and the headrest 6 are provided as optional items. The armrest device 4 is a set of left and right pairs, but only one of them is shown in the figure.

The leg device 1 has a leg support 7 made of a gas cylinder, and the leg support 7 is supported by a plurality of branch arms 8 extending radially. A caster is provided at the tip of each branch arm 8. As shown in FIG. 3, a fixed base 9 is attached to the upper end of the leg column 7, and the tilting base 10 is supported by a horizontally long support shaft 11 in a portion of the fixed base 9 on the front side of the leg column 5. It is connected so that it can tilt backward. With the fixed base 9 and the tilting base 10 as main members, a base portion to which the seat 2 and the backrest 3 are attached is configured.

As shown in FIG. 4, the seat receiving member 12 is supported by the fixed base 9 and the tilting base 10. A back support frame 13 to which the backrest 3 is attached is fixed to the tilting base 10. Accordingly, the backrest 3 locks together with the tilting base 10. Further, the seat receiving member 12 moves backward and backward in conjunction with the backward tilt of the tilt base 9. Accordingly, the seat 2 moves backward and backward (synchronizes) in conjunction with the backward tilting of the backrest 3. The armrest device 4 is fixed to the seat receiving member 12.

Although not shown, a locking spring that provides resistance to locking is disposed inside the fixed base 9. The hardness of the locking spring can be adjusted, for example, by rotating the elasticity adjusting handle 14 shown in FIG. The elasticity adjustment handle 14 is arranged on the right side when viewed from the seated person, and is arranged simultaneously with the support shaft 11. A lock handle 15 that controls the tilting of the backrest 3 is disposed on the opposite side of the elasticity adjusting handle 14. The lock handle 15 is also arranged coaxially (concentrically) with the support shaft 11.

As shown in FIG. 4, the seat 2 has a structure in which a seat cushion material 17 is stretched on a seat inner shell 16 made of synthetic resin. The seat 2 is attached to a seat outer shell 18 disposed below the seat 2. The seat outer shell 18 is arranged behind the seat main outer shell 18a, the seat main outer shell 18a fixed to the seat receiving member 12, the seat front outer shell 18b slidably mounted on the seat main outer shell 18a, and the seat main outer shell 18a. And a seat rear outer shell 18c. Therefore, the seat 2 can also be considered as a structure in which the three parts of the main part, the front part, and the rear part are integrated. The seat rear outer shell 18c is connected to the seat main outer shell 18a by a horizontally long pin so as to be vertically rotatable.

On the other hand, the seat inner shell 16 includes a seat main inner shell 16a fixed to the seat main outer shell 18a, a seat front inner shell 16b integrally connected to the front end of the seat main inner shell 16a, and a seat main inner shell 16a. The rear inner shell 16c is integrally connected to the end. The seat front inner shell 16b has a horizontally long slit, and can be wound downward and deformed. When the seat front outer shell 18b is retracted, the seat front inner shell 16b is wound downward. As a result, the longitudinal length (depth) of the seat 2 is increased. Get smaller.

The seat rear inner shell 16c of the seat inner shell 16 is continuous with the seat main inner shell 16a so as to turn up and down around its front end. The rear end of the seat rear inner shell 16c is connected to the lower end of the backrest 3 by left and right horizontally long pins. For this reason, when the backrest 3 is locked, the seat 2 is generally retracted and tilted backward, while the seat rear inner shell 16c is tilted relatively backward with respect to the seat main inner shell 16a.

(2). Outline of the backrest appearance Next, the outline of the backrest will be described. As can be understood from FIGS. 7 and 8, the backrest 3 includes a back outer shell 23 and a back cushion material 24 disposed in front of the back shell 3 as main elements. The back outer shell 23 is an example of a body support. As clearly shown in FIG. 2D, the backrest 3 (or the back outer shell 23 and the back cushion material 24) is divided into three areas: a center area 25 and left and right side areas 26 in the left-right direction. In the vertical direction, the upper stage area 27, the middle stage area 28, and the lower stage area 29 are divided into three stages.

Accordingly, the backrest 3 is divided into nine elements: an upper center element a, a middle center element b, a lower center element c, left and right upper side elements d, left and right middle side elements e, and left and right lower side elements f. . The elements a to f are common to the back outer shell 23 and the back cushion material 24. When the backrest 3 is displayed as an element as a whole, the symbols a to f are simply quoted. On the other hand, when elements as elements of the back outer shell 23 and the back cushion member 24 need to be individually displayed, reference numerals a to f are appended to 23 and 24, respectively.

More precisely, the back outer shell 23 includes a back outer shell upper stage center element 23a, a back outer shell middle stage element 23b, a back outer shell lower stage center element 23c, a back outer shell upper stage side element 23d, and a back outer shell middle stage side element 23e. The back outer shell lower side element 23f is divided. Similarly, the back cushion material 24 includes a back cushion material upper center element 24a, a back cushion material middle center element 24b, a back cushion material lower center element 24c, a back cushion material upper side element 24d, a back cushion material middle stage element 24e, It is divided into cushion material side elements 24f.

In the back cushion material 24, a groove 30 opened forward is formed at the boundary between adjacent elements 24a to 24f. The location of the groove 30 is a thin hinge. Therefore, the back cushion material 24 is manufactured as a single member, and the adjacent elements a to f are separated by the groove 30. Each element 24a to 24f of the back cushion material 24 has a plateau shape due to the presence of the groove 30, but the surface that the body hits is substantially flat. The backrest 3 (the back outer shell 23 and the back cushion material 24) has a symmetrical shape.

As shown in FIGS. 2A and 2C, the upper center element a and the lower center element c are slightly trapezoidal trapezoids, and the middle center element b is an inverted trapezoid whose vertical and horizontal dimensions are the same. The upper side element d is generally an inverted trapezoid, the middle side element e is a trapezoid that is vertically long, and the lower side element f is an inverted triangle. Therefore, the backrest 3 is narrowed by the upper area 27 and the middle area 28 in a front view, and is swollen by the middle area 28 and the lower area 29. The backrest 3 can be formed in a vertically long rectangular shape or an inverted trapezoidal shape as a whole when viewed from the front.

Further, as can be understood from FIG. 1, the side elements d to f are inclined so as to face toward the front with respect to the center elements a to c. That is, the side elements d to f are inclined so as to wrap around the body of the seated person. Therefore, the backrest 3 has a forward concave shape in plan view. On the other hand, as clearly shown in FIG. 2 (C), the backrest 3 is formed in a side view from the middle area 28 and the lower area 29 so as to form a forward-convex mountain shape. 25), a convex portion L is formed on which the waist of the seated person hits. Precisely, the convex portion L is formed by the middle center elements 24b and 23b of the back cushion material 24 and the back outer shell 23, and the lower center elements 24c and 23c.

On the other hand, the upper stage area 27 and the middle stage area 28 are bent in a slightly forward concave shape in a side view. The upper-stage center element a and the middle-stage center element b can be formed in a flat shape, or conversely, can be bent into a forward convex shape in a side view.

In the back outer shell 23 and the back cushion material 24, the upper center elements 23a, 24a and the middle center elements 23b, 24b are integrated so as not to be relatively rotatable. Accordingly, in the back cushion material 24, the groove 30 formed at the boundary between the upper center element 24a and the middle center element 24b is provided mainly for the purpose of enhancing the aesthetics by having uniformity with other grooves. It is a thing and does not bend at this part. In the back outer shell 23 and the back cushion member 24, the other adjacent elements are connected so as to be relatively rotatable.

The back support frame 13 is a metal die-cast product or a resin molded product, and has a back column 13 a extending upward behind the backrest 3. The middle center element 23b of the back outer shell 23 is connected to the upper end of the back column 13a with left and right horizontally long pins (details will be described later). Therefore, the back strut 13a and the backrest 3 can be rotated relative to each other during locking.

2B, the hanger 5 and the headrest 6 are fixed to the back outer shell upper stage center element 23a. That is, the optional product support plate 31 shown in FIG. 7A is fixed to the front surface of the upper end portion of the upper outer shell center element 23a with screws. First, the hanger 5 has its lower end portion connected to the upper outer shell upper stage. It is fastened to the optional product support plate 31 with screws together with the center element 23a.

On the other hand, the headrest 6 has a structure in which a core plate 32 is wrapped with a back cushion material 33. A downward foot plate 33 is fixed to the core plate 32, and the foot plate 33 is screwed on the front surface of the optional product support plate 31. It is concluded. The shaft portion of the screw for fastening the foot plate 34 passes through the optional product support plate 31 and is screwed into the foot plate 34.

As shown in FIG. 5, the lower end of the lower outer shell lower center element 23c is connected to the rear end portion of the seat rear outer shell 18c with left and right horizontally elongated pins 38. For this reason, connecting convex portions 39 and 40 arranged on the left and right are formed at the lower end of the lower outer shell lower center element 23c and the rear end of the seat rear outer shell 18c.

In addition, the lower end of the back outer shell 23 may be connected to the rear end of the seat 2 or may be connected to the back support frame 13 and the bases 9 and 10. Or it is also possible to attach with respect to the upper end part of the back support | pillar 13a in the state which tilts back and forth only to some extent. That is, the lower end of the back outer shell 23 is not necessarily connected to another member.

(3). Deformation of the backrest In FIGS. 3 (A) to (C), the reference state (neutral state) in the non-locking state and where the person does not put his back on the backrest 3 is indicated by the symbol N. The shape of the backrest 3 in the working state (posture) in which the seated person has the upper body substantially upright is indicated by the symbol F. In the working state F, the seated person's waist hits the backrest 3. Since the lower center element c is connected to the seat rear outer shell 18c, when the seated person sits down only on the convex portion L of the backrest 3, the convex portion L moves backward, and the middle center element b and the lower center center The opening angle with the element c is increased. And the upper center element a moves forward.

That is, the backrest 3 tilts forward with respect to the neutral state N in the work state F. 3A depicts a state in which the lower end of the backrest 3 is retracted backward, but in practice, the front and rear positions of the lower end of the backrest 3 are constant. As shown in FIG. 2C, an elastic body 41 such as rubber is disposed between the upper end portion of the back column 13a and the back outer shell middle stage element 23b, and the back outer shell middle stage element 23b is made of an elastic body. 41 is deformed and rotated to the near side. Therefore, the backrest 3 is maintained in the neutral state N by the elastic body 41.

That is, in the neutral state N, the elastic body 41 is not loaded at all, or even if it is loaded, the stress is balanced and held in the reference state. For this reason, when the elastic body 41 is in the reference state, the relative angle between the back outer shell middle element 23b and the back column 13a is kept constant. As a result, the backrest 3 is held in the neutral state N.

On the other hand, since the upper and lower three-stage side elements d to f are connected in the vertical direction, when the opening angle between the middle center element b and the lower center element d increases, the depression angle with respect to the center elements a to c decreases due to the pushing-out action. It turns to the near side so that it may become. Accordingly, the side elements a to c rotate in a direction to wrap the seated person's body, and the holding action on the seated person's body is enhanced. As a result, the seated person can work for a long time without getting tired.

In FIG. 3 (B), the posture of the backrest 3 in the rocking state in which the seated person leans against the middle center element b and the upper center element a is indicated by the symbol R. However, in FIG. 3 (B), the state in which the lower end of the backrest 3 is advanced with respect to the neutral state N is displayed, but this shows a tendency of movement. Tilt backwards.

Therefore, the rocking state R shown in FIG. 3 (B) shows the relationship with the neutral state N. When the backrest 3 shifts to the locking state R, the backrest 3 tries to shift to a backward tilting movement around the upper end of the back column 13a, but the lower end of the backrest 3 is connected to the seat rear outer shell 22. Therefore, the amount of backward tilt relative to the neutral state N is small.

The backrest 3 tilts relatively backward with respect to the neutral state N due to the rearward tilt angle of the back support frame 13 being larger than the rearward tilt angle of the seat outer shell 18. And the depression angle formed by the lower center element c becomes smaller. In other words, since the seated person stretches the body when rocking, the human body pressure is applied to the middle center element b and the upper center element a, so that the depression angle formed by the middle center element b and the lower center element c is small. . Then, since the side elements d to f are connected to each other, the side elements d to f are pushed out by the center elements a to c, and as a result, the side elements d to f widen the depression angle with respect to the center elements a to c. Rotate (bend). Therefore, the backrest 3 spreads and deforms in a direction toward a flat state in plan view.

When the seated person shifts from the office posture to the rocking posture, the depression angle formed by the middle center element b and the lower center element c decreases. Then, the side elements d to f adjacent to each other tend to pull each other, and as a result, the side elements d to f spread and deform so as to increase the depression angle with the center elements a to c.

Then, the side elements d to f spread away from the seated person from the state of being narrowed so as to wrap the seated person. That is, it changes so that it may shift to a flat state. Accordingly, in the rocking state, the holding ability of the body by the side elements d to f decreases or disappears, and as a result, the releasing ability of the body increases. Therefore, a person can obtain high comfort. Note that the side elements d to f are not completely parallel to the center elements a to c, but are tilted slightly toward the front even when they are fully expanded. Therefore, the deterrent function against excessive lateral shift of the body is ensured.

In FIG. 3C, the left and right upper side elements d display only the work status F. In addition, the lower side element f displays the three states of the neutral state N, the working state F, and the locking state R on the right side, and shows the two states of the neutral state N and the locking state R on the left side. Overlaid.

3C shows a state in which the upper elements a and d are retracted with respect to the neutral state N in the rocking state R, but actually, the backrest 3 is inclined backward as a whole. Therefore, at the time of locking, the upper elements a and d are displaced backward (downward in the drawing) from the position indicated by (C).

(4). Back inner frame As described above, the backrest 3 includes the back outer shell 23 and the back cushion member 24 as main elements. In this embodiment, each of the back inner shell 23 and FIG. As shown in the figure, a back inner frame 42 is provided as a main element. The back inner frame 42 is an example of an inner member, and is a molded product made of a resin such as polypropylene. The back inner frame 42 is also an example of a shape retaining member that retains and reinforces the shape of the back cushion material 24.

The back inner frame 42 has a frame structure opened front and rear, and the back cushion material 24 is fixed (adhered) to the back inner frame 42 by insert molding. As shown in FIGS. 13 and 16, a skin material 24 'is stretched on the surface of the cushion material 24. The skin material 24' is also bonded to the cushion material 24 by insert molding.

As can be understood from FIG. 7, the back inner frame 42 is not fixed to the middle center element 24 b of the back cushion material 24. As can be easily understood from this, the back inner frame 42 does not have to be fixed to all the elements of the back cushion material 24. And since the back inner frame 42 has the surrounding frame part 43, even if the whole is not adhere | attached on the back cushion material 24, there is no problem about the shape retention function of the back cushion material 24. Further, since the middle center element 24b of the back cushion material 24 is in a free state not restricted by the back inner frame 42, the back cushion material 24 can be easily deformed as a whole.

Set back inner frame 42 on one of the mold of the dense adhesion and separate from freely pair of molds, set the skin material 24 'on the other die, the cushion in the cavity between the two mold in this state By injecting and solidifying the molten material of the material 24 ′, the cushion material 24 is bonded to the back inner frame 42, and at the same time, the skin material 24 ′ is bonded to the surface of the cushion material 24. Is done. The back inner frame 42 and the skin material 24 ′ are held on the mold so as not to fall off, for example, by vacuum suction.

As a means for integrating the inner frame 42, the cushion material 24 and the skin material 24 ′, instead of insert molding, the three members are overlapped and sandwiched with a mold, and the three members are clamped only at the groove 30. An integrated method can also be adopted. In this case, for example, a hot melt adhesive is applied to the groove 30 and the groove 30 can be formed and the three members can be joined simultaneously by heating.

As shown in each of FIGS. 6 to 9, the back inner frame 42 includes a loop-shaped peripheral frame portion 43 that overlaps the back surface of the outer peripheral portion of the back cushion material 24, and a left and right longitudinal portion that overlaps the upper end portions of the middle stage elements 31 and 34. Of the horizontal joint portion 44, and a frame portion 45 connected to the upper end portion of the peripheral frame portion 43 and the horizontal joint portion 44.

Further, in the back inner frame 42, the adjacent elements 24 a to 24 f of the back cushion material 24 are allowed to rotate relative to each other at the groove 30 (thin hinge portion) of the back cushion material 24. A portion 46 is formed. The horizontally long joint portion 44 is connected to the peripheral frame portion 45 via a hinge portion 46. As shown in enlarged views in FIGS. 14 and 15, the hinge portion 46 is formed in a zigzag shape in a front view. For this reason, the deformation of the hinge portion 46 is further facilitated.

Further, as shown in FIG. 9C, the hinge portion 46 is convex toward the front side (the back cushion material 24 side) when viewed from the outer peripheral direction such as a side view, a plan view, and a bottom view. Is bulging (curved). Due to the synergistic action of the zigzag shape and the forward convex bulge shape, the hinge portion 46 is easily deformed in three dimensions such as expansion and contraction, bending in the front-rear direction, and twisting. As a result, the adjacent elements 24a to 24f of the back cushion material 24 can be bent relatively easily while freely changing the posture.

Therefore, when the back cushion member 24 is viewed as a whole, it can be smoothly deformed to follow the body of the seated person. This is a great advantage of this embodiment.

The back inner frame 42 basically has a band plate structure, but, for example, as shown in FIG. 9B, the lower portion 43a where the lower end portion of the back cushion material lower center element 24c overlaps has a cross section. An L-shaped laterally long reinforcing portion 47 is provided. As shown in FIG. 13, the reinforcing portion 47 covers a forward rib 48 formed in the lower outer shell lower center element 23 c. For example, as shown in FIG. 9, a large number of through holes 49 into which the back cushion material 24 enters are formed in the peripheral frame portion 43. The resin constituting the back cushion material 24 enters the through hole 49 and plays a role like a rivet, thereby preventing the back cushion material 24 from being detached (peeled).

The frame portion 45 of the back inner frame 42 is provided mainly for assisting attachment to the back outer shell 23. For example, as shown in FIG. 9, the left and right intermediate portions are formed in an X shape for weight reduction. In addition, a vertically long plate-like portion 50 is provided on both the left and right sides thereof. A connection hole 51 for connection to the back outer shell 23 is formed in the vertically long plate-like portion 50, the peripheral frame portion 45, and the horizontally long joint portion 44.

The connecting holes 51 are formed one by one in the vertically long plate-like portion 50, and one by one in the laterally long joint portion 44 at a position below the vertically long plate-like portion 50. On the other hand, a large number of connecting holes 51 are formed in the peripheral frame portion 43 in a jumping manner. Further, the connecting hole 51 has a horizontally long shape at the portion of the vertically long plate-like portion 50, but at the portion of the peripheral frame portion 43 and the horizontally long joint portion 44 in the longitudinal direction of the peripheral frame portion 43 and the horizontally long joint portion 44. It is a long slot. The connection between the back inner frame 42 and the back outer shell 23 is performed using a clip attached to the connection hole 51, which will be described later.

In the forehead portion 45, a portion between the left and right vertically long plate-like portions 50 is a groove-like portion 52 that is recessed toward the front. Although this groove-shaped part 52 has the auxiliary function of attachment of the headrest 6, details are abbreviate | omitted.

Further, since the frame portion 45 overlaps the back cushion material upper center element 24a, and the horizontally long joint portion 44 overlaps the back cushion material middle center element 24b, the frame portion 45 and the horizontally long joint portion 44 do not bend. It has become. In other words, the upper center element 24a and the middle element 24b of the back cushion member 24 are relatively rotated even if the groove 30 is present by adopting a structure in which the frame portion 45 and the horizontally long joint portion 44 are not bent. The structure is not bent.

(5). Significance of the back inner frame Now, Patent Documents 1 and 2 are described based on the embodiment (first embodiment). In Patent Documents 1 and 2, the backrest has a center area and left and right in the left-right direction. The center area and the side area are divided into the upper, middle, and lower stages, respectively. Therefore, the backrest consists of 9 elements (parts) as a whole. And the adjacent element is connected via the hinge part so that relative rotation is possible. Japanese Patent No. 5562001 discloses a seat in which cushion members are arranged in series on the upper surface of a seat inner shell, and a rear portion of the seat is bent downward by forming a hinge portion on the seat inner shell. ing.

Patent Documents 1 and 2 disclose that an element (side element) located in a side area rotates (bends) in conjunction with locking, and comfort of the element can be improved by the movement of such an element. It can be said.

The back inner frame 42 of the present embodiment is made in view of such a current situation, and is intended to improve the reliability of the movement of the element and the durability of the body support in the body support in which the element bends. It is what.

The inner frame technology in the present embodiment can be applied to body support members such as a seat, a headrest, and a shelder rest in addition to the backrest of the chair. And in this embodiment, the surface side which a human body hits is comprised with a cushioning material, and the shell body is arranged on the back side of the cushioning material, and at least the cushioning material can be bent relatively. The structure is partitioned into elements, and the inner frame in the form of a frame is attached to the back surface of the cushion material so as not to spread over the entire back surface of the cushion material so as to straddle adjacent elements. In addition, a boundary portion between adjacent elements in the inner frame is a hinge portion, and the inner frame is attached to the shell body.

In the above configuration, since the inner frame plays a role of reinforcing the cushion material, high durability can be ensured. Although it is troublesome to attach the cushion material directly to the shell body, in the present invention, since the cushion material is attached to the shell body via the inner frame, it is easy to assemble a body support such as a backrest. Furthermore, since the bending fulcrum of the cushion material is defined by the hinge portion of the inner frame, the bending movement of the element is also accurate.

Although various forms can be adopted for the inner frame, if the form having the peripheral frame part 43 as in the embodiment is adopted, the outer frame of the cushion material is defined by the peripheral frame part 43. However, the shape retention of the cushioning material can be improved. Further, since the bending of the cushion material 24 is not impaired by the inner frame 42, the bending deformation of the body support body such as the backrest 3 as a whole can be easily and reliably performed.

(6). Back outer shell For example, as shown in FIG. 8, the back outer shell 23 has a separate structure except that the upper center element 23a and the middle center element 23b are integrated. For example, as shown in FIGS. 8 and 13A, adjacent elements 23a to 23f are integrally connected by a band hinge 55 made of an elastomer. The band hinge 55 is a band-shaped soft resin material.

As shown in FIG. 8, reinforcing ribs 56 that are continuous with the upper center element 23a and the middle center element 23b are formed on the front surfaces thereof. Each element 23a to 23f is formed in a shell shape (tray shape) having forward ribs (walls) around it. Therefore, each element constituting the back outer shell 23 can also be called a shell.

As clearly shown in FIG. 13 (A), the band hinge 55 overlaps the front surface of the elements 23a to 23f, and the band hinge 55 is slightly exposed on the back side. For this reason, the portion of the band hinge 55 appears in a grooved state on the back surface of the back outer shell 23 (see also FIG. 6A). For example, as shown in FIG. 6A, a laterally long groove 57 is formed at the boundary between the upper center element 23a and the middle center element 23b of the back outer shell 23. The horizontally long groove 57 is provided for the purpose of design, and is not bent at this point.

15A and 15B, the hinge portion 46 of the back inner frame 42 is disposed so as to overlap the band hinge 55 of the back outer shell 23 from the front.

The band hinge 55 is formed by a two-color molding method or insert molding. In FIGS. 13C and 13D, a two-color molding method is displayed. In this two-color molding method, a mold apparatus having a movable mold (cavity) 58 and a fixed mold (core) 59 is used, and arranged on a mating surface of both molds 58 and 59 at a predetermined position and posture. A unit space 60 corresponding to each element 23a to 23f is formed. In each unit space 60, a gate (not shown) is opened. The gate is generally provided in the fixed mold 59.

For example, a portion of the movable mold 58 that spans the adjacent unit spaces 60 is constituted by a slide mold 61 that slides in the same direction as the moving direction of the movable mold 58, and the elastomer 61 is injected into the slide mold 61. A gate 62 is provided. Since the slide mold 61 has a shape corresponding to the band hinge 55 and is connected in series, the gate 62 may be one (preferably a plurality of locations).

Also, the gate 62 can be provided in the fixed mold 59 (this method is practical). In this case, the gate 62 is located between adjacent elements (unit shells) of the back outer shell 23. In other words, the band hinge 55 can be formed by providing the gate 62 on the fixed mold 59 by providing a certain distance between adjacent elements of the back outer shell 23.

Further, a forward-facing rib is formed on the outer periphery of each of the elements 23a to 23f constituting the back outer shell 23, and the band hinge 55 overlaps the end surface of the rib. Therefore, the band hinge 55 can be formed while increasing the rigidity of the elements 23a to 23f.

In the mold apparatus, each element 23a to 23f is formed by injecting molten resin into each unit space 60 in a state where the slide mold 61 is advanced and then hardening, and then the slide mold 61 is moved backward. Thus, a space corresponding to the band hinge 55 is formed, and a molten elastomer is injected into this space and hardened. After the elastomer is hardened and the band hinge 55 is formed, the mold is opened and the product is taken out.

Thus, when the two-color molding method is adopted, each of the elements a to f can be accurately positioned, so that the back outer shell 23 can be manufactured with high accuracy. Further, since the band hinge 55 is accurately formed, the connection strength between the elements is excellent. As a means for forming the band hinge 55, an insert molding method can also be employed. This is because a mold apparatus that does not include the slide mold 61 is used and the elements 23a to 23f are set at predetermined positions of the mold apparatus, and then an elastomer is injected into the space corresponding to the band hinge 55 to be solidified. It will be.

As shown in FIG. 14, FIG. 15, and FIG. 8, a protrusion 55a is provided at the upper end of the band hinge 55 and the tip of the portion connecting the upper side element 23d and the middle side element 23e. The protrusion 55 a covers a protrusion (not shown) formed in the element of the back outer shell 23. For this reason, the band hinge 55 is more reliably prevented from being peeled off from the elements 23a to 23f.

As a means for preventing the band hinge 55 from peeling off, the band hinge 55 is molded into a boss projecting from the back outer shell 23, and the tip of the boss is crushed to make a head. It is possible to hold it down. Alternatively, the pressing plate may be overlapped with the band hinge 55 from the front, and the pressing plate may be fixed to the back outer shell 23.

For example, as can be understood from FIGS. 8 and 14 to 16, each of the elements 23 a to 23 f constituting the back outer shell 23 has a forward rib 63 formed in a portion constituting the outer periphery of the backrest 3. The back inner frame 42 is disposed in a recess surrounded by the rib 63. For this reason, the back inner frame 42 is held so as not to be displaced. For example, as shown in FIG. 8, each element 23a to 23f of the back outer shell 23 is provided with a connecting rib 64 projecting forward so as to overlap the connecting hole 51 of the back inner frame 42 in front view (the connecting structure is (It will be described later.)

(7) Significance of Back Outer Shell Patent Documents 1 and 2 disclose “film hinges” and “material bridges” as hinge means for rotatably connecting adjacent elements. In addition, as a hinge portion of the back outer shell, US Pat. No. 4,711,491 as Patent Document 3 discloses that a part of the back outer shell is formed in a corrugated shape.

Patent Documents 1 and 2 do not describe the “film hinge” and “material bridge” as illustrated, but in any case, it is unclear whether durability, strength, or smooth bending can be sufficiently secured. It is. Further, in US Pat. No. 4,711,491, a part of the back outer shell is formed as a hinge portion, but the structure of US Pat. No. 4,711,491 is composed of a number of elements as in Patent Documents 1 and 2. If it is, it is assumed that it is difficult to apply. There is also a concern that the form of the waveform gives a person a sense of incongruity.

This embodiment is also intended to improve the current situation.

This embodiment can be widely applied not only to the backrest but also to a body support for a chair such as a seat or a headrest. This body support is composed of “a plurality of elements that can rotate relative to each other, and adjacent elements are connected by hinges. Each element has a unit shell body as a strength member. And the hinge is composed of a band-shaped soft resin material integrally formed with adjacent unit shell bodies. As the belt-like soft resin material, an elastomer is preferable.

According to the above configuration, since the strip-shaped soft resin material is integrally formed with the unit shell body, high adhesive strength can be ensured, and there is no uneven adhesion, and the processing accuracy is excellent. Further, since the hinge is made of a soft resin material different from that of the unit shell body, the hinge is smooth and excellent in durability and strength. Furthermore, in a chair, the outer shell such as the back outer shell is usually a three-dimensional shape. However, by integrally molding the belt-shaped soft resin material, adjacent unit shell bodies can be reliably and accurately formed. Can be linked. Therefore, it is excellent in reliability. Since the belt-like soft resin material is flat, it does not give a sense of incongruity to humans even if it is exposed, and is excellent in aesthetics.

In addition, since the belt-like soft resin material is deformed in any direction, even when a large number of body supports are composed of elements as in Patent Documents 1 and 2, adjacent elements can be easily rotated relative to each other. be able to.

(8). Connection structure between the back outer shell and the back column As described above, the upper end of the back column 13a is connected to the middle center element 23b of the back outer shell 23 so as to be relatively rotatable. This point will be described with reference to FIGS. As shown in FIG. 11, the left and right laterally long boss portions 66 are integrally formed at the upper end of the back column 13 a in a forward inclined posture in a side view, and the left and right laterally long connecting pins 67 are inserted into the boss portions 66. Has been. The connecting pin 67 protrudes from the left and right sides of the boss portion 66.

On the other hand, a holding portion 68 that covers the boss portion 66 of the back column 13a protrudes rearward from the center portion 23b of the back outer shell, and as clearly shown in FIG. Has an insertion hole 70 into which the boss 66 and the connecting pin 67 are fitted from below.

As clearly shown in FIG. 11A, the holding portion 68 of the back outer shell 23 is a space of a forward opening surrounded by the reinforcing rib 71, and the connection pin 67 is placed inside this space. A pair of left and right bearing portions 72 with the left and right exposed portions overlapping from the front are projected forward, and the left and right exposed portions of the connecting pin 67 are pressed by the pressing member 73 to hold the connecting pin 67 so as not to be detached. Yes. The pressing member 73 is fixed to the holding portion 68 with four screws 74. Further, as clearly shown in FIG. 10, the pressing member 73 is formed with a pressing portion 73 a that presses both ends of the connecting pin 67 from the front side. A boss portion 66 is located between the left and right pressing portions 73a.

Thus, by using the pressing member 73, the connecting pin 67 can be held in a state where it cannot be seen from behind. Further, since the movement of the connecting pin 67 in the left-right direction is blocked by the holding portion 68, a retaining means such as a snap ring is unnecessary. Of course, the connecting means between the back column 13 a and the back outer shell 23 is arbitrary, and it is also possible to connect the boss portion 63 with a connecting pin inserted through the holding portion 68.

The back outer shell 23 is connected to the back column 13a at a slightly upper portion of the middle center element 23b. Therefore, when the seated person leans against the backrest 3, the backrest 3 tends to tilt backward about the connecting pin 64.

(9). Back tilt control structure As shown in FIGS. 10A and 12, the elastic body 41 described above is disposed immediately below the boss 63 of the back column 13a. The elastic body 41 is made of, for example, rubber (Cherast), but a spring body such as a coil spring can also be used. The elastic body 41 basically has a rod shape that is long in the front-rear direction, but the outer periphery is recessed so that the front-rear intermediate part has the smallest diameter. For this reason, it has a shape similar to an hourglass.

A metal ring 41a is fixed to the front and rear surfaces of the elastic body 41 by bonding or the like, and this ring 41a is fastened to the back outer shell middle stage center element 23b and the back column 13a with bolts 77. Therefore, the ring 41a also functions as a nut. The back outer shell middle stage center element 23b and the back column 13a are formed with receiving seats 76a and 76b in close contact with the ring 41a. A countersink hole 78 for storing the bolt 76 is formed on the rear surface of the back column 13a. It is also possible to project a screw shaft at both ends of the elastic body 41 and fix the screw shaft to the back outer shell middle stage center element 23b and the back column 13a with a nut (this configuration is more elastic body). 41 is preferable because the entire 41 can be deformed).

In FIG. 12B, for convenience, the neutral state N, the working state F, and the locking state R are displayed as three lines. In the neutral state N in which no body pressure is applied to the backrest 3, the elastic body 41 is in a free state in which neither compression nor extension is performed. In other words, since the restoring force does not act on the elastic body 41, the backrest 3 is held in the neutral state N.

When only the convex part L of the backrest 3 is pushed by the seated person's waist and the backrest 3 moves to the working state F, the middle center element 23b is connected so that its upper end moves forward and its lower end moves backward. It rotates around the pin 67. Accordingly, the distance between the middle center element 23b and the back column 13a is narrowed. Therefore, the elastic body 41 undergoes compressive deformation and bending deformation. In other words, by elastically deforming the elastic body 41, the middle stage center element 23b rotates so that the upper end moves forward.

In the transition from the neutral state N to the work state F, the elastic body 41 is deformed to warp upward in a side view. Since the elastic body 41 is shaped like an hourglass, the elastic body 41 can be easily bent and deformed. Therefore, the transition from the neutral state N to the work state F is performed smoothly. When the seated person moves the upper body from the office state F to the near side, the backrest 3 returns to the neutral state N by the restoring force of the elastic body 41.

In the locking state R, the center of the body pressure of the seated person is above the center of rotation of the backrest 3 (the connecting pin 67). Therefore, when shifting from the neutral state N to the locking state R, the middle stage center element 23b With respect to the neutral state N, the upper end moves backward and the lower end moves backward so that the lower end moves forward. Therefore, the distance between the back column 13a and the back outer shell middle center element 23b is wider than in the neutral state N. Accordingly, the elastic body 41 extends and deforms with respect to the neutral state N and bends and deforms so as to warp downward.

When shifting from the working state F to the locking state R, the elastic body 41 once returns to the free state and then stretches and deforms. When the body is lifted from the locking state R, the backrest 3 returns to the neutral state N by the restoring force of the elastic body 41. In addition, it is performed by the rocking spring that the backrest 3 moves to the front generally. The elastic body 41 is for controlling a change in posture with respect to the neutral state N or a change in relative posture between the back column 13 a and the backrest 3.

Also in Patent Documents 1 and 2, the backrest rotates relative to the back column. And the spring element 26 is provided as a return means for returning a backrest to the original position where the body pressure of a seated person is not applied. However, in Patent Documents 1 and 2, in the backrest 3, only the side element is narrowed from the original posture and deformed, and therefore, the spring element is only compressed in the locked state.

On the other hand, in the present embodiment, the backrest 3 changes its posture relative to the working state F and the locking state R with the neutral state N as a boundary, and accordingly, the elastic body 41 is compressed. The deformation mode differs between deformation and elongation deformation. The elastic body 41 is bent in the working state F and the locking state R in a bending direction that is bent downward and in a bending direction that is upward.

Looking at this in reverse, by reversing the deformation mode of the elastic body 41, the backrest 3 may change its posture in the opposite direction from the neutral state N to the working state F and the locking state R. It can be said that it is possible. Accordingly, it is possible to easily and reliably change the posture of the backrest 3 between the working state F and the rocking state R while holding the backrest 3 in the neutral state N with no load applied using one type of elastic body 41. It has been realized. This is one of the great advantages of this embodiment.

(10). Connection Structure of Back Inner Frame and Back Outer Shell, etc. Next, the connection means between the back inner frame 42 and the back outer shell 23 will be described mainly with reference to FIGS. In this embodiment, the clip 79 shown in FIG. 16 is used for the connection between the back inner frame 42 and the back outer shell 23. For example, as shown in FIG. 9, a group of plate-like forward ribs 80 corresponding to the connection holes 51 of the back inner frame 42 are provided on the back outer shell 23 so as to protrude forward. By fitting the clip 79 to the plate-like rib 80, the back inner frame 42 is connected to the back outer shell 23, and as a result, the back cushion material 24 is connected to the back outer shell 23.

The clip 79 is made of a metal plate such as a stainless steel plate or spring steel, and has a pair of side plates 81 connected to a mountain shape. 16 (A) and 16 (D), the clip 79 is inserted into the connecting hole 51 of the back inner frame 42 from the back in a posture with a mountain first. The connecting hole 51 of the back inner frame 42 is formed in a forward-facing rib 80 that is slightly spaced from the back outer shell 23, and the connecting hole 51 is formed at the tip (free end) of the side plates 81. A holding portion 82 that holds the longitudinal opening edge portion 51a from the front and rear is bent.

Therefore, the clip 79 is held in the back inner frame 42 so as not to be separated from the front and rear. A step portion 83 facing the back cushion material 24 is formed at the longitudinal opening edge of the connecting hole 51, and therefore the longitudinal opening edge portion 51a is stepped down. Therefore, the holding portion 82 is disposed in a state shifted rearward from the front surface of the forward rib 80.

The forward-facing rib 80 provided on the back outer shell 23 has a tapered shape whose thickness decreases toward the tip (front end), and is inserted between the two side plates 81 of the clip 79. Further, the side plate 81 of the clip 79 is formed by cutting and raising a holding piece 84 that sandwiches the forward rib 80 inward, and the nail 85 that bites into the forward rib 80 is cut and raised one by one on the holding piece 84. Yes.

More precisely, first, the front end portions of the both sandwiching pieces 84 are formed in the guide portions 84a whose distances are widened toward the back outer shell 23, whereby the forward ribs 80 of the both sandwiching pieces 84 are formed. Invited smoothly. Further, the claw 85 extends from the guide portion 84 a toward the connecting portion of the both side plates 81, and the distance between the tips of the opposed claws 85 is set to be smaller than the thickness of the forward rib 80. Yes.

For this reason, when the forward rib 80 is pushed into the clip 79, the claw 85 bites into the forward rib 80. Thereby, the back inner frame 42 is held so as not to be detached from the back outer shell 23. Two claws 85 are formed on one sandwiching piece 84, but can be formed one by one or three or more.

In this embodiment, the back cushion material 24 is bonded to the back inner frame 42 by insert molding. Since the back cushion material 24 is soft, the clip 79 can be inserted into the connection hole 51 while the back cushion material 24 is filled in the connection hole 51 and the clip 79 is pushed away. Alternatively, it is also possible to form a space in which the clip 79 fits in the back cushion material 24 by forming a protrusion similar to the outer shape of the back cushion material 24 in the insert molding die.

Further, in the above description, the connection between the back inner frame 42 and the back outer shell 23 has been described as a method of inserting the forward rib 80 into the clip 79. However, in practice, the clip 79 is generally pushed into the forward rib 80. It can be said that. In this case, the clip 79 is pressed against the forward rib 80 via the back cushion material 24.

The edge of the skin material 24 ′ covering the back cushion material 24 is wound around the back side of the back inner frame 42, but a hole in which the clip 79 is fitted is formed in the edge of the skin material 24 ′, and the skin material 24 ′ It is also possible to clean the edges and attach the clip 79 together. Of course, the edge of the skin material 24 ′ may be fixed to the back inner frame 42 with a tucker, or may be bonded with an adhesive.

In the present embodiment, the skin material 24 ′ is integrated with the back cushion material 24 at the same time as the insert molding to the back inner frame 42. That is, by forming the back cushion material 24 with the skin material 24 ′ set in the mold, it is easily realized that the skin material 24 a is held in the groove 44 as clearly shown in FIG. 13. it can. Of course, it is also possible to form the back cushion material 24 in advance and then adhere the skin material 24 ′ to the back cushion material 24 with an adhesive or the like. Alternatively, the skin material 24 ′ may be overlaid on the back cushion material 24, and the edge of the skin material 24 ′ may be fixed to the back inner frame 42 with a tucker or the like.

As clearly shown in FIG. 16A (see also FIG. 14 and FIG. 15), the back inner frame 42 is surrounded by a rib 63 on the outer periphery of the back outer shell 23. Therefore, even if the back inner frame 42 is provided, the problem of aesthetics does not occur. Further, as described above, since the back inner frame 42 is accurately positioned with respect to the back outer shell 23, the positional relationship between the clip 79 and the forward rib 80 can be accurately matched. For this reason, even if the clip 79 and the forward rib 80 are not visible, each clip 79 can be accurately attached to the forward rib 80 by simply pressing the portion of the back cushion member 24 where the clip 79 is located.

For example, as shown in FIGS. 6 and 7A, the backrest 3 of the present embodiment also includes a lumbar support device 88 for adjusting the support height of the waist of the seated person. The lumbar support device 88 includes a lumbar support body 89 that hits the back cushion material 24 from behind, an operation lever 90 for moving the lumbar support body 89 up and down, and a support bracket 91 that holds the lever 90 so that its height can be adjusted. It has. As indicated by reference numeral 92 in FIG. 8, a recess 94 surrounded by a rib 93 is formed on the front surface of the lower end portion of the back outer shell middle element 23b, and the support bracket 91 is fixed to the recess 94 so as not to be displaced. Has been.

The upper end of the operation lever 90 is fixed to the back surface of the upper end of the lumbar support body 89 with screws. And the operation lever 90 is exposed below from the insertion hole 95 (refer FIG. 10) provided in the lower end part of the back outer shell middle stage element 23b. Therefore, the seated person can turn the operation lever 90 up and down by turning his / her hand behind the backrest 3. The support bracket 91 is provided with a tongue piece protruding upward in front of the operation lever 90, and a forward engagement protrusion is provided at the upper end of the tongue piece, while an engagement protrusion is provided on the front surface of the operation lever 90. A large number of engaging grooves for fitting and disengaging are formed in multiple stages. Due to the elastic deformation of the tongue piece, the engagement protrusion and the engagement groove are engaged and disengaged.

As described above, the back inner frame 42 is not fixed to the back cushion material center element 24b. As can be understood from FIG. 7A, the center middle stage element 24b and the center lower stage element 24c of the back cushion member 24 are in a state of being freely deformable (turnable). For this reason, the raising / lowering motion of the lumbar support body 89 is not inhibited, and the change of the height position which supports a seated person from back can be ensured.

(11). Significance of lumbar support device It is widely practiced to provide a lumbar support device on the back. In order to adapt to the height and preference of the user, the lumbar support body is also configured to be adjustable in height. On the other hand, as a structure of the backrest, there is one in which a back cushion material is disposed in front of a resin-made back outer shell (back cover). Thus, in the backrest provided with the back outer shell, it becomes a problem how to lift and lower the lumbar support body.

In this regard, Japanese Patent No. 5529501 discloses that the operating portion (operating lever) is exposed from the position of the mating surface between the left and right end portions of the back outer shell and the left and right end portions of the back cushion material. That is, in Japanese Patent No. 5529501, the operation unit is exposed to the outside from the left and right side portions of the backrest. Therefore, the operation unit protrudes from the left and right outer sides of the backrest. However, in this configuration, there is a concern that an object hits an operation part (for example, a bag) of a person passing by the side or clothes of a person passing by are caught on the operation part.

The lumbar support device of the present embodiment is also aimed at improving such a current situation.

Then, when the present embodiment is laid down, a chair provided with a lumbar support device, “a back cushion material or other body support member is arranged in front of the back outer shell constituting the back of the backrest, and the body support In a configuration in which a lumbar support body that supports the waist of the seated person via the body support member is disposed between the member and the back outer shell so that the height can be adjusted. The lumbar support body is formed on the front side of the bent portion, and the lumbar support body is disposed on the front side of the bent portion, while the back outer shell is above the apex of the bent portion. There is an insertion hole for exposing an operation part for raising and lowering the lumbar support body at a location, and the operation part extends downward from the insertion hole. , It can be presented as a configuration that.

In this configuration, since the operation unit is located behind the back outer shell, there is no inconvenience that a person's object or clothes passing next to it will hit or get caught. Moreover, since the operation part is exposed using the insertion hole provided in the back outer shell, the back outer shell and the back cushion material can be fixed over the entire circumference. Therefore, there is no problem that the attachment strength of the back cushion material is reduced, or that the appearance is impaired due to a gap in the mating surface between the back cushion material and the back outer shell. It is also possible to adopt a configuration in which a vertically long slot is formed in the back outer shell and the operation lever (knob) is exposed from the slot.

(14). Design Features of the Chair In this embodiment, the back cushion material 24 is composed of nine elements 24a to 24f, and the front surfaces of the elements 24a to 24f are composed of a skin material 24 '. . The skin material 24 ′ is made of cloth (cloth), synthetic leather, or the like, but in any case, the skin material 24 ′ is integrally bonded to the back cushion material 24 by insert molding. It is glued in a stretched state.

Accordingly, as clearly shown in FIG. 13 (A), the front surface of the backrest 3 is composed of a skin material 24 ′ that is stretched without wrinkles, and the elements 24 a to 24 f are divided by the grooves 30. Yes. Further, the skin material 24 ′ also enters the groove 30. In addition, as a feature of the present embodiment, each element 24a to 24f has a substantially trapezoidal shape (or plateau shape) having a flat surface and a peripheral skirt portion due to the presence of the groove 30. Therefore, the part which hits a seated person's body is basically flat. This also applies to the seat cushion material 17.

And since the part where the seated person's body hits is flat, the seater's back / waist hits the backrest 3 and the entire surface of the seat 2 evenly. For this reason, the reaction force acting on the back and waist is also widely distributed on the back and waist. For this reason, there is no local push-up feeling and a high usability can be obtained. Note that the outer peripheral portions of the elements 24a to 24f may be square or rounded.

As clearly shown in FIG. 1, the upper surface of the seat 2 (in other words, on the seat cushion material 17) is divided into five elements 2a to 2d by a groove 96. That is, with the center element 2a having a trapezoidal shape in plan view as a main element, the center front element 2b positioned in front of the center element 2a, the rear element 2c positioned behind the center element 2a, the center element 2a, and the left and right sides of the rear support portion 17c It is divided into side elements 2d located on both sides. Therefore, the upper surface of the seat cushion material 17 is divided into a plurality of parts in both the left-right direction and the front-rear direction. The groove 96 is the same as the groove 30 of the backrest 3 (FIG. 13A).

The seat cushion material 17 is integrally bonded to the seat inner shell 16 by insert molding, similarly to the back cushion material 24. Further, the adhesion of the skin material to the seat cushion material 17 is performed simultaneously with the molding of the seat cushion material 17. In insert molding, the skin material is set in a mold facing the mold in which the seat inner shell 16 is set. Specifically, it is set in the mold by vacuum suction or adhesion by an adhesive (this is the same for the back cushion material 24).

In Patent Documents 1 and 2, the backrest is divided into nine elements, and in FIG. 1, the fold line that is the boundary between adjacent elements is displayed as a simple line. In FIGS. 1 and 2 of Patent Documents 1 and 2, it is understood that each element is displayed in a mountain shape protruding forward. Although the shape of the upper surface of the seat cannot be clearly grasped, it seems that there are multiple mountain-shaped areas. In other words, it is assumed that the seat also has a backrest and design unity.

In Patent Documents 1 and 2, the boundaries of the elements constituting the backrest are clear, and thus it can be said that the user's attention is drawn as an unprecedented design. However, if each element is Yamagata, some users may feel uncomfortable. Therefore, even if it is composed of a plurality of elements, it can be said that there is a demand for a smoother design.

In the present embodiment, one of the problems and purposes is to further refine the design of Patent Documents 1 and 2 and improve the smoothness of hitting the body.

Features adopted in this embodiment as a means for achieving the design purpose are as follows:
1): In a chair provided with a body support in which a cushioning material is stretched on the side where the human body hits, the cushioning material is continuous in a series as a whole, and the surface is partitioned into a plurality of elements by grooves. The surface of each element defined by the groove is flat. It can be laid with the first design invention.

The body support in the laid invention includes a backrest, a seat, a headrest, an elbow rest, a sheller rest, and the like. Furthermore, the design features of this embodiment can also be applied to a chair in which the element does not bend. The first design invention can be developed in various ways as exemplified in the following 1) to 7).

2). Second design invention: In the first design invention, on the front surface of the back cushion material constituting the backrest as the body support, a plurality of the back cushion materials are divided into a plurality of parts in both the left and right directions and the vertical direction. Grooves are formed.

3). In the first design invention, the third design invention: a plurality of seat cushion materials on the upper surface of the seat cushion material constituting the seat as the body support body, the seat cushion material being divided into a plurality of parts in both the left-right direction and the front-rear direction. Grooves are formed.

4). In any one of the first to third design inventions, the back cushion material is divided into a plurality of parts in both the left and right directions and the vertical direction on the front surface of the back cushion material constituting the backrest as the body support. While a plurality of grooves are formed, on the upper surface of the seat cushion material constituting the seat as the body support body, a plurality of grooves that divide the seat cushion material into a plurality in both the left-right direction and the front-rear direction The pattern of the element in the back cushion material and the element in the seat cushion material are in a form close to symmetry.

5). In any one of the first to fourth design inventions, a skin material is stretched on the surface of the cushion material, and the skin material is fixed to the cushion material integrally by insert molding. It enters the inside of the groove and is bonded to the cushion material in a stretched state as a whole.

6). In any one of the first to fifth design inventions, the backrest as the body support body includes a back outer shell constituting the back surface thereof and a cushion material constituting the front surface thereof. On the front side, a plurality of grooves are formed to divide the back cushion material into a plurality of directions in both the left and right directions and the up and down direction, while the back surface of the back outer shell is symmetrical with the grooves of the cushion material. Grooves are formed in.

The back cushion material and the back outer shell have hinge portions at all or a plurality of portions of the groove.

7). In any one of the first to sixth design inventions, the geometric pattern is constituted by a group of a plurality of linear grooves.

In the above design invention, since the cushion material spreads in a series as a whole, the assembly of the body support is easy and the dimensional accuracy is also increased. Further, since the surface of each element is flat, it is possible to give a favorable impression to a person without excessive decoration. That is, it can be refined in design. Moreover, since each element is flat, the body supporter hits the human body over a wide area, so that fit to the body can be improved.

Furthermore, in this embodiment, when viewed from the above-mentioned design aspect, the back outer shell 23 and the seat 2 can be seen at the same time in the back view of the chair, but the geometric pattern and design based on trapezoids and triangles are both unified. Therefore, even in the rear view (back view), an excellent cosmetic effect is exhibited. Therefore, it can be said that it is preferable to make the patterns and patterns of the surfaces of the backrest 3 and the seat 2 uniform. When representing a geometric pattern, it is also possible to combine one or more types of other polygons such as a square or a hexagon. As in the embodiment, it is preferable to divide the back surface of the backrest into grooves in the same manner as the front surface because the front view and the back view can be unified.

In the embodiment, the elements 23a to 23f and 24a to 24f are bent (rotated) by the pushing action of the seated person, but the elements 23a to 23f and 24a to 24f may be configured to simply rotate against elasticity. Is possible. In other words, the elements 23a to 23f and 24a to 24f may be configured to bend backward against the elasticity by being pressed by the body pressure of the seated person instead of being bent in conjunction with the locking, for example. is there.

In the design features, the number, shape and arrangement of the elements of the backrest 3 and the seat 2 are not limited to the embodiment and can be arbitrarily set. For example, as a modification of the embodiment, there may be an aspect in which the upper area 27 (a, d) is not provided. It is also possible to configure only the backrest 3 in a geometric pattern or configure only the seat 2 in a geometric pattern. Further, both the backrest 3 and the seat 2 are formed in a striped pattern in which a plurality of elements are arranged in a plurality of upper and lower steps or a plurality of front and rear rows, or in a striped pattern in which a plurality of elements are arranged in a plurality of left and right rows. It is also possible to do. It is also possible to unify with a polka dot pattern.

Furthermore, an example of the development of design features is also shown in FIG. That is, FIG. 27 shows another example of the pattern formed by the grooves 30 and 96. In each of the drawings, the backrest 3 and the seat 2 are displayed in a state where they are unfolded on the same plane, and both the seat 2 and the backrest 3 have a structure in which a seat cushion material is stretched with a skin material.

In FIG. 27, the seat 2 and the backrest 3 are unified with a square frame pattern in (A), unified with a horizontal stripe pattern in the example of (B), unified with vertical stripes in (C), (D ) Is standardized by vertical and horizontal grid patterns. (E) is a combination of a circle and a radial line. (F) is applied to a bench for three people, and both the seat and the backrest 3 are unified with a cross-lined pattern. It is also possible to make the concept of unbalance without having the uniformity of the design and pattern of the seat and the backrest.

The design invention can be applied to optional items such as headrests, shoulder rests, and elbow pads. These optional products can be unified with the pattern of the groove and the backrest or seat, or can have a unique design. It is also possible to make the backrest and the seat pattern different from each other.

(12). Base part The chair of this embodiment is improved also about the seat 2 and its support mechanism. This point will be described next. First, the base portion will be described mainly with reference to FIGS.

As described above, the base portion includes the fixed base 9 and the tilt base 10 as main members. Among these, the fixed base 9 is a die-cast product or a cast product, as can be understood from FIG. 19A and FIG. 17B, for example, and has a shallow box shape with an upward opening having left and right side plates 9a and bottom portions. Is formed. The upper end of the leg strut 7 is fitted from below into a cylindrical boss 125 having an upper and lower opening provided at the rear. The front portion of the fixed base 9 is inclined in a side view so as to become higher toward the front.

On the other hand, as shown in FIGS. 19 (A) and 17 (B), the tilting base 10 has a left and right side plate 10a and a rear plate 10b and is opened up and down, and the rear plate 10b faces upward. The opened back support portion 10c is fixed. The back support portion 10c is formed in a bowl shape with an upward opening having left and right side plates, and the front end portion of the back support frame 13 is fitted therein. As shown in FIG. 17A, the back support frame 13 is fixed to the back support portion 10c with a plurality of bolts 126.

The tilting base 10 is made of a metal plate, and is arranged so that the side plate 10 a is positioned outside the side plate 9 a of the fixed base 9. That is, the tilting base 10 covers the fixed base 9 from the outside. As shown in FIG. 19A, the front end portion of the side plate 10 a of the tilting base 10 is connected to the fixed base 9 by the support shaft 11.

For example, as shown in FIG. 19A, the front upper ends of the left and right side plates 10a of the tilting base 10 are connected by a laterally long front joint 127. Therefore, the tilting base 10 has a frame structure opened up and down by the left and right side plates 10a, the rear plate 10b, and the front joint 127.

As can be understood from FIG. 17B, a front fixed spring receiver 128 is disposed below the front joint 127. The front fixed spring receiver 128 is connected to the fixed base 9 and the tilting base 10 by the support shaft 11, but is held by a stopper shaft 129 provided on the fixed base 9 so that it cannot be tilted forward. Therefore, the position and posture are fixed.

As shown in FIG. 20, a wedge-shaped lifting body 130 is disposed on the rear surface of the front fixed spring receiver 128, and a front movable spring receiver 131 is disposed on the rear surface of the wedge-shaped lifting body 130. ing. The wedge-shaped lifting body 130 has a smaller front-rear width as it goes down. For this reason, when the wedge-shaped lifting body 130 moves up and down, the front movable spring receiver 131 moves back and forth. The front movable spring receiver 131 is held so that it only moves back and forth and does not move up and down.

A rear spring receiver 132 is fixed to the rear portion of the fixed base 9, and a pair of left and right locking springs (compression coil springs) 133 are sandwiched from the front and rear by the front movable spring receiver 131 and the rear spring receiver 132. Yes. Therefore, the rocking spring 133 acts against the rear tilt of the tilt base 10.

The wedge-shaped lifting body 130 is screwed with a vertically long screw shaft 134. The upper end of the screw shaft 134 is held by a front joint 127 so as to be rotatable and unable to move up and down. The lower end of the screw shaft 134 is rotatably held by a lower support piece 137 (see also FIG. 17B) provided on the front fixed spring receiver 128. The screw shaft 134 is held by the front joint 127 and the lower support piece 137 so as not to move up and down.

The lower beveled first bevel gear 138 is fixed to the lower end of the screw shaft 134. On the other hand, a second bevel gear 139 that meshes with the first bevel gear 138 is fixed to the tip of the elasticity adjusting handle 14. Accordingly, when the elasticity adjusting handle 14 is rotated, the screw shaft 134 is rotated via the bevel gears 138 and 139, whereby the wedge-shaped lifting body 130 is moved up and down, and the front movable spring receiver 131 is interlocked with this. Move back and forth.

The elasticity adjusting handle 14 has a cylindrical shape and is fitted to the support shaft 11 from the outside. Accordingly, the elasticity adjusting handle 14 serves as a bearing for the support shaft 11. Further, the height adjustment handle 15 has a cylindrical shape and is fitted to the support shaft 11 from the outside. Therefore, the height adjustment handle 15 also serves as a bearing for the support shaft 11. The push valve protruding from the upper end of the leg column 7 is pushed downward by the rotation operation of the height adjustment handle 15, but the description of the mechanism is omitted.

For example, as shown in FIGS. 19A and 20, a front link 140 extending above the fixed base 9 is connected to the front end portion of the fixed base 9 by a first shaft 141 that is horizontally long. Therefore, the front link 140 can be rotated in the front-rear direction around the lower end thereof. The front portion of the seat receiving member 12 is connected to the upper end of the front link 140 by a horizontally elongated second shaft 142.

As shown in FIG. 20, a compression coil spring 143 is disposed between the front link 140 and the front fixed spring receiver 131. Accordingly, the front link 140 is biased forward by the compression coil spring 143. However, as can be understood from FIG. 18B, the forward tilt angle of the front link 140 is restricted by the lower end of the front link 140 hitting the front end of the fixed base 9.

As shown in FIGS. 19A and 18A, the seat receiving member 12 has a vertically long frame 1144. The vertically long frame 144 has an L-shaped cross section in which an upper flange 144a facing left and right is formed at the upper end. A horizontally long front stay 145 and a rear stay 146 are fixed to the left and right upper flange 144a by welding. Yes. Therefore, the seat receiving member 12 has a frame structure opened up and down. The front stay 145 and the rear stay 146 protrude beyond the left and right sides of the vertically long frame 144. The armrest device 4 shown in FIGS. 1 and 2 is fixed to the lower surface of the protruding portion of the rear stay 146 via a spacer (not shown).

FIG. 19B shows a state in which the seat outer member 18 is covered with the seat receiving member 12 from above, and the front stay 145 of the seat receiving member 12 is partially visible. The seat outer shell 18 is fixed to the upper flange 144a of the seat receiving member 12 (see FIG. 19A) with screws. For this reason, as shown in FIG. 19A, the left and right upper flanges 144a of the seat receiving member 12 are provided with two screw insertion holes 147 at the front and rear.

As shown in FIGS. 18A and 19A, the longitudinal frame 144 of the seat receiving member 12 has its front portion connected to the upper end of the front link 140 by the second shaft 142, and its rear portion tilted. The base 10 is connected to the rear end of the base 10 by a horizontally elongated third shaft 148. Therefore, when the tilting base 10 is tilted rearward, the seat receiving member 12 tilts rearward while rearward. However, the rearward tilt angle of the seat receiving member 12 is smaller than the rearward tilt angle of the tilting base 10.

(13). Structure of Seat Next, the seat 2 will be described mainly with reference to FIGS. 21 and 22 (see also FIG. 4). The seat inner shell 16 is a molded product made of a resin such as polypropylene, and has an integral structure as a whole. For example, as shown in FIGS. And a seat front inner shell 16b positioned in front of the seat main inner shell 16a and a seat rear inner shell 16c positioned behind the seat main inner shell 16a.

For example, as can be accurately understood from FIG. 24, the seat front inner shell 16b and the seat rear inner shell 16c have approximately the same front-rear width, and roughly each have a front-rear width of about 1/4 of the total length. On the other hand, the seat main inner shell 16a has a front-rear width of about half of the total length. For example, as shown in FIG. 21A, the seat inner shell 16 (and the seat cushion material 17) is recessed upward so as to conform to the profile of a person's buttocks and thighs. The seat front inner shell 16b is curved in a side view so as to become lower as it goes to the front end.

The seat main inner shell 16a is a part that stably supports the seated person. Therefore, it basically has a rigid structure. However, in order to ensure cushioning properties, for example, as shown in FIG. 21A, a group of slits 151 opened up and down is provided. The group of slits 151 is a mixture of a longitudinally long and a slanted posture in plan view, and is arranged around a portion where the tailbone of the seated person hits.

For example, as shown in FIGS. 21A and 24, the front portion of the seat main inner shell 16a is a downward bank portion 152 that is recessed downward. For this reason, high rigidity is ensured. Inside the downward bank portion 152, longitudinal longitudinal ribs 153 are formed side by side in a lateral direction.

Further, for example, as shown in FIG. 21, an upper tape holding portion 154 is formed at a substantially left and right intermediate portion of a portion of the downward bank portion 152 that is divided into half on the left and right halves. The upper tape holding portion 154 is for locking (fixing) the rear end portion (one end portion) of the tape 155 (see FIG. 21) for winding the seat front inner shell 16b together with the seat cushion material 17 downward. As shown in an enlarged view in FIG. 21B, two front and rear bars 157 and 158 are arranged in the space of the upper and lower openings sandwiched between the left and right ribs 156.

The tape 155 is an example of a flexible member, and is composed of a fabric such as a knitted fabric or a woven fabric (a tough fabric tape). Then, as shown in FIG. 26 (B), the rear end of the tape 155 is wound around the back bar 158 and then held in a loop shape by a fastener such as eyelet. Therefore, the front bar 157 serves as a guide body that suppresses the tape 155 from being bent excessively.

The tape 155 can be fixed by various other methods. For example, the rear end of the tape 155 can be fixed with a screw. Alternatively, a hook may be fixed to the rear end of the tape 155 and the hook may be locked to the bar. Furthermore, it is also possible to draw out the tape 155 around the bar and then pull it forward in a state of two layers. Since the tape 155 overlaps the upper surface of the seat front inner shell 16b, the insert molding of the seat cushion material 17 is performed with the tape 155 attached to the seat inner shell 16.

The seat front inner shell 16b is a deformation allowing portion for allowing downward entanglement deformation. As shown in FIGS. 21, 22, etc., as a weakening means for allowing deformation, a plurality of rows of horizontally long slits 159 arranged in the front-rear direction are formed. The band-like portions 160 adjacent to each other on the front and rear sides across the horizontally long slit 159 are connected by bridges 161 at both left and right ends. The bridge 161 has an inverted U shape (mountain shape) protruding upward in order to facilitate entrainment deformation. It is also possible to arrange three or more bridges 161 at one horizontal slit 159.

For example, as can be understood from FIG. 22 (A) and FIG. 26 (B), the belt-like portion 160 divided by the horizontally long slit 159 has a bowl-like shape opened upward, and is reinforced by ribs. Therefore, the thigh of the seated person is stably supported by the front part of the seat 2. The front end 162 of the seat front inner shell 16b in front of the group of the horizontally long slits 159 basically has a plate structure, but is reinforced by a number of ribs. Therefore, the front inner shell 16b is not excessively deformed, and the supporting function as the seat 2 is maintained.

Further, for example, as shown in FIGS. 21A and 22A, a tape holding groove 164 for restricting the left and right positions of the tape 155 is formed in the belt-like portion 160 and the tip portion 162 constituting the seat front inner shell 16b. Is forming.

For example, as shown in FIGS. 22A and 24, between the seat main inner shell 16a and the seat rear inner shell 16c, there are left and right lateral center slits 165 and watermark holes 166 arranged on both sides thereof. Intervene. In other words, the boundary between the seat main inner shell 16a and the seat rear inner shell 16c is a hinge portion by the center slit 165 and the watermark hole 166.

The seat main inner shell 16a and the rear inner shell 16c are composed of a first bridge 167 located between the seat center slit 165 and the watermark hole 166, and a second bridge 168 located on the left and right outside of the watermark hole 166. It is connected. Therefore, the seat rear inner shell 16c can tilt backward with respect to the seat main inner shell 16a. The first bridge 167 has a simple mountain shape, and the second bridge 168 has a waveform shape. Accordingly, the left and right side portions of the seat rear inner shell 16c are allowed to largely escape and rotate with respect to the seat main inner shell 16a.

As described above, the groove 96 constituting the geometric pattern is formed on the upper surface of the seat inner shell 16. In this case, as shown in FIG. 26, left and right laterally long grooves 96 are first formed above the front and rear middle portions of the seat front inner shell 16b. For this reason, it is easy for the front part of the seat to be rolled downward and deformed.

It is also possible to form a horizontally elongated groove 96 above the rear end of the seat front inner shell 16b. In this case, the groove 96 is not bent at the location of the groove 96 until the end of the winding. The significance of forming the weakened portion (hinge portion) is reduced. On the other hand, as shown in the figure, when the groove 96 is provided on the front and rear intermediate portion of the deformed portion made of the group of the horizontally long slit 159 and the bridge 161, the portion of the groove 96 is bent from the beginning of the winding, so that the seat 2 There is an advantage that the deformation of the front part is performed with a light force and accurately.

(14). Basic Structure of Seat Outer Shell Next, the seat outer shell 18 will be described mainly with reference to FIGS. For example, as clearly shown in FIG. 22A, the seat outer shell 18 includes a seat main outer shell 18a on which the seat main inner shell 16a overlaps, a seat front outer shell 18b corresponding to the seat front inner shell 16b, and a seat rear inner shell. It is comprised by three members with the seat rear outer shell 18c corresponding to the shell 16c.

These three members 18a to 18c are manufactured as separate members. The seat front outer shell 18b is slidably attached to the seat main outer shell 18a, and the seat rear outer shell 18c is attached to the seat main outer shell 18a. It is connected so that it can tilt backward. The seat main outer shell 18a has a function of stably supporting the seated person's body, and a number of reinforcing ribs are formed on the upper surface in order to ensure rigidity.

As shown in FIG. 22 (A), a pair of connecting recesses 170 opened rearward are formed at the rear end of the seat main outer shell 18a. On the other hand, at the front end of the seat rear outer shell 18c, a pair of left and right connecting convex portions 171 that fits into the connecting concave portion 170 are projected forward, and the connecting concave portion 170, the connecting convex portion 171, and the like. Are connected by left and right longitudinal pins 172. Therefore, the seat rear outer shell 18c can be inclined backward relative to the seat main outer shell 18a.

As shown in FIG. 22 (A), the connecting convex portion 171 of the seat rear outer shell 18c is raised upward. Therefore, a watermark hole 166 is provided at the boundary between the seat main inner shell 16a and the seat rear inner shell 16c to prevent the connecting convex portion 171 from hitting. That is, the watermark hole 166 of the seat inner shell 16 is for allowing the connecting convex portion 171 to escape upward.

A large number of reinforcing ribs are formed on the seat rear outer shell 18c. Further, the lateral width of the seat rear outer shell 18c is set to be considerably smaller than the lateral width of the seat main outer shell 18a. Accordingly, the lateral width of the seat rear outer shell 18 c is smaller than the lateral width of the seat rear inner shell 16 c in the seat inner shell 16.

As shown in FIG. 22A and FIG. 25, the left and right side portions of approximately the front half of the seat main outer shell 18a become groove-shaped fixed guide portions (downward protruding ridge portions) 173 that are greatly recessed downward. The portion between the left and right fixed guide recesses 173 is basically a flat support portion 174. The front end of the support portion 174 enters slightly behind the front ends of the left and right fixed guide portions 173.

On the other hand, the seat front outer shell 18b includes left and right movable guide portions 175 that are slidably fitted back and forth to the fixed guide portion 173 of the seat main outer shell 18a, and a supported portion that overlaps the support portion 174 of the seat main outer shell 18a from above. 176. Although the seat front outer shell 18b slides back and forth, the supported portion 176 does not leave in front of the support portion 174, and the rear end portion rests on the support portion 174 even in a fully advanced state. The seat front outer shell 18b is provided with a number of ribs for reinforcement.

For example, as can be understood from FIG. 25, the fixed guide portion 173 of the seat main outer shell 18a is basically in the form of a trapezoid that is narrowed in front view, but can be understood from FIG. In order not to hinder the rotation operation of the handles 14 and 15, the relief recess 177 is formed in a shape that is depressed downward.

22A, the fixed guide portion 173 has an inner surface (inner plate) 173a, an outer surface (outer plate) 173b, and a support rib 173c constituting the lower surface. The inner side surface 173a has a substantially vertical posture, and the outer side surface 173b is inclined so as to be shifted outward in the left-right direction. On the other hand, as shown in FIG. 25, the movable guide portion 175 of the seat front outer shell 18 b corresponds to the fixed guide portion 173 and has an inner side surface (inner plate) 175 a in a vertical posture and an outer side surface (outer plate in an inclined posture). ) 175b and a flat bottom surface (bottom plate) 175c. Due to the fitting of the guide portions 173 and 175, the seat front outer shell 18b can slide back and forth with no backlash.

As shown in FIG. 22A and FIG. 25, female screw holes 178 for fixing to the seat receiving member 12 are formed in the front and rear portions of the seat main outer shell 18a. A portion of the female screw hole 178 is an upward boss portion, and the screw is screwed into the female screw hole 178 from below. The seat main outer shell 18a and the seat receiving member 12 may be fixed by other means.

(15). Other guide means for the seat front outer shell As can be understood from FIG. 25 (A), for example, the lower surface of the supported portion 176 in the seat front outer shell 18b is basically flat. The supported portion 176 is supported in a stable state by the support portion 174. The supported portion 176 and the support portion 174 are provided with two types of guide means that also serve as a retainer.

That is, as an element of the first guide means, as shown in an enlarged view in FIG. 22B, the front and rear longitudinal fixed guide rails 179 are provided at the left and right sides of the support portion 174 with the left and right intermediate portions sandwiched therebetween. The longitudinal dovetail grooves 180 are formed on the opposing surfaces of the left and right fixed guide rails 179.

Further, as shown in FIG. 25A, left and right fixed guides are formed by forming escape grooves 181 for avoiding buffering with the fixed guide rails 179 in the supported portion 176 of the seat front outer shell 18b. A movable guide rail 182 positioned between the rails 179 is formed, and a slide projection 183 that fits into the dovetail groove 180 of the fixed guide rail 179 is provided at the rear end of the movable guide rail 182. Therefore, the longitudinal movement of the seat front outer shell 18b is guided, and the seat front outer shell 18b is held so as not to be upwardly pulled out with respect to the seat main outer shell 18a.

Next, the second guide means will be described. As the second guide means, first, as shown in FIG. 22 (A), a cylindrical guide boss 184 protrudes from a portion closer to the front end of the support portion 174 and outside the left and right sides of the fixed guide rail 179. On the other hand, a longitudinally extending guide groove 185 into which the guide boss 184 is fitted is formed in the supported portion 176 of the seat front outer shell 18b, and the screw 186 shown in FIG. 24 is screwed into the guide boss 184 from above. Yes. Therefore, the head of the screw 186 plays a role of retaining.

Since the front and rear longitudinal fixed guide rails 179 and the front and rear longitudinal guide grooves 185 are formed in pairs on the left and right, the seat front outer shell 18b can slide back and forth in a stable state without swinging left and right. Since the guide boss 184 is positioned in front of the fixed guide rail 179, the seat front outer shell 18b overlaps with the seat main outer shell 18a so that the guide groove 185 fits into the guide boss 184, and then slides backward. The slide protrusion 183 can be fitted into the dovetail groove 180 by the procedure described above.

Since the front / rear slide stroke of the seat front outer shell 18 b is defined by the guide groove 185, the slide protrusion 183 does not come off the dovetail groove 180. The screw 186 is screwed after the slide protrusion 183 is fitted into the dovetail groove 180. The seat front outer shell 18b is a support portion for the seat front inner shell 16b, but this support portion can be attached to a member other than the seat main outer shell 18a, such as the seat receiving member 12 or the base. Various means such as a link mechanism can be employed as the slide mechanism.

(16). Tape attachment structure to the seat front outer shell, etc. For example, as shown in FIGS. 22A and 26, the front end of the seat front outer shell 18b is a lower portion for attaching the other end of the tape 155. A tape holding portion 187 is formed. As shown in FIG. 26, the lower tape holding portion 187 has a horizontally long groove 188 that opens in the front and rear directions, and the front end (the other end) of the tape 155 is a hole 162a provided in the front end portion 162 of the seat front inner shell 16b. After passing through the horizontally long groove 188, it is fixed to the back surface of the lower tape holding part 187 by a pressing plate 189. The holding plate 189 is fixed to the wall of the lower tape holding part 187 with screws 190. Various connecting means such as a hook can be adopted for the front end portion of the tape 155.

When the seat front outer shell 18 b is retracted, the front end of the seat front inner shell 16 b in the seat inner shell 16 is pushed downward and backward by the tape 155. Therefore, the seat front inner shell 16b is deformed so as to be wound downward together with the seat cushion material 17 (see the one-dot chain line in FIG. 26B). Thereby, the front-rear width (depth) of the seat 2 changes. When the seat front outer shell 18b is advanced, the front portion of the seat 2 is returned to its original state and deformed by the elastic restoring force of the seat front inner shell 16b and the seat cushion material 17.

In this embodiment, the seat cushion material 17 is integrated with the seat inner shell 16 by insert molding, enters the horizontally long slit 159, and also fills the inside of the belt-shaped portion 160. For this reason, the seat cushion material 17 plays the role of an elastic body that stretches the seat front inner shell 16b. As a result, even if the return means such as a spring is not provided, when the seat front outer shell 18b is advanced, the front portion of the seat 2 is reliably returned and deformed.

In the present embodiment, the seat front inner shell 16b is wound downward while being pressed from above by the tape 155, so that the front portion of the seat 2 does not swell upward or near during the winding deformation.

In other words, in the case of the configuration in which the front end of the seat front inner shell 16b is pulled, the eyes of the horizontally long slits 159 may tend to be widened at the time of winding. In this embodiment, since the seat front inner shell 16b is pressed from above by the tape 155, the opening of the horizontal slit 159 does not occur, so that the appearance is excellent.

Further, since the deformation allowing portion of the seat front inner shell 16b is held so as to overlap the seat front outer shell 18b, the seat front inner shell 16b can be prevented from floating upward. Also in this aspect, it is excellent in aesthetics. Moreover, since it is not necessary to provide an engagement means in the seat front inner shell 16b and the seat front outer shell 18b, it is possible to contribute to simplification of the structure.

The tape 155 can be pushed backward from the lower end of the front end of the seat front inner shell 16b, but in this case, the seat front inner shell 16b may be raised upward. In this regard, as in the present embodiment, when the tape 155 is passed backward from the hole 162a provided in the distal end portion 162a of the seat front outer shell 18b, the position where the seat front inner shell 16b is pulled can be made as high as possible. There is an advantage that the seat front inner shell 16b can be pulled downward to prevent the floating more reliably. Even if a slit groove is provided instead of the hole 162a, the same advantage can be obtained.

In the present embodiment, the two tapes 155 are arranged on the left and right, but can be arranged, for example, on the middle position on the left and right and on the outer three sides. Alternatively, it is possible to arrange only one flexible member formed on a wide strip at the left and right intermediate portions. Instead of the tape 155, it is also possible to adopt a string or a wire. In this case, it may be arranged at a plurality of locations on the left and right.

In this embodiment, the seat rear outer shell 18c tilts backward with respect to the seat main outer shell 18a, but the present invention can also be applied to a type that does not include the rear tilt type seat rear outer shell 18c. Various means can be employed as means for deforming the seat front inner shell 16b, such as thinning and thinning, and forming a plurality of laterally elongated grooves in the front and rear.

In the present embodiment, the seat front inner shell 16b is supported by the seat front outer shell 18b. However, the seat front inner shell 16b can be supported by a slide member that is mounted on the seat receiving member 12 so as to be movable back and forth. . Moreover, the length adjustment mechanism using a flexible member such as a tape or string can be applied to the backrest. When applied to the backrest, the back outer shell is fixed to the fixed back outer shell so that the back upper outer shell can be moved up and down, and the upper end of a flexible member such as tape is locked to the back upper outer shell. Or just fix it.

(17). Mounting structure of seat inner shell to seat outer shell The seat main inner shell 16a is fixed to the seat main outer shell 18a, and this fixing uses the clip 79 described for the backrest 3. Therefore, as shown in FIGS. 22 and 23, connecting holes 51 are formed at four positions on the front and rear left and right sides of the seat main outer shell 18a, and clips 79 are fitted into the connecting holes 51 from the back side. Further, a projecting plate portion 802 that is clamped by a clip 79 is formed on the seat main outer shell 18 a of the seat outer shell 18.

As can be clearly seen from FIG. 24, the front connecting hole 191 has a horizontally long form, and the rear connecting hole 191 has a front and back long form. For this reason, the seat inner shell 16 exhibits a high resistance to both the forward and backward displacement and the lateral displacement.

The seat rear inner shell 16c of the seat inner shell 16 is connected to the seat rear outer shell 18c at two left and right positions. That is, as shown in FIG. 23 (A), a pair of left and right hook protrusions 193 are projected upward on the seat rear outer shell 18c, while the seat rear inner shell 16c is enlarged in FIG. 23 (C). As shown, an engagement hole 194 into which the hook protrusion 193 is fitted is formed.

The hook projection 193 has a T-shape having a head, while the engagement hole 194 has a wide portion 194a into which the hook projection 193 can be fitted and removed. After the hook projection 193 is fitted into the wide portion 194a, the seat rear When the inner shell 16c is shifted to the front, the seat rear inner shell 16c is held so as not to be separated upward with respect to the seat rear outer shell 18c.

When the seat 2 is attached, the seat rear inner shell 16c is first attached to the seat rear outer shell 18c, and then the seat main inner shell 16a is pressed downward with the hook protrusion 193 as a fulcrum, so that The attached clip 190 is fitted into the protruding plate portion 191 of the seat main outer shell 18a. The seat main outer shell 18a may be fixed to the seat receiving member 12 by other means such as screws. Further, when the seat receiving member 12 is not provided, it may be directly fixed to the base.

For example, as shown in FIG. 22A, the seat main outer shell 18a is formed with a plurality of base protrusions 195 that support the seat main inner shell 16a. The base protrusion 195 is also provided at the rear part of the support part 174. Therefore, the seat front outer shell 18b is formed with a notch 196 for avoiding a collision with the base protrusion 195.

As shown in FIG. 19B, a knob 197 is exposed from the square hole from the left side surface of the seat main outer shell 18a. The knob 197 is a part of a lever device that adjusts the depth of the seat 2. As shown by reference numerals 197 and 198 in FIG. 25 (A), a hole for attaching the lever device is formed on the left side surface of the seat main inner shell 16a. The description of the lever device is omitted. As shown in FIG. 25A, a knob 199 can also be seen on the right side surface of the seat main inner shell 16a. This is a dummy knob for facilitating the forward / backward movement operation of the seat 2.

(18). Significance of Depth Adjustment Device In a chair, as a method for adjusting the depth of a seat, a front portion of the seat is configured as a deformable portion that can be wound downward. One example thereof is disclosed in Japanese Patent Laid-Open No. 2013-220180.

That is, Japanese Patent Application Laid-Open No. 2013-220180 is an application of the applicant of the present application, and a seat outer shell on which a seat inner shell is supported is fixed to a seat outer member, and a fixed outer shell is slidable back and forth on the stationary outer shell. The front end portion of the seat inner shell is locked to the distal end portion of the slide outer shell. Further, as a feature of Patent Document 1, the slide outer shell is placed on the fixed outer shell over the entire left and right widths even when the slide outer shell is fully advanced.

In Japanese Patent Laid-Open No. 2013-220180, the slide outer shell is supported by the fixed outer shell over the entire left and right widths in the full stroke of the forward and backward movement, so that the seat stability is excellent. Due to such advantages, high reliability can be obtained even if it is actually embodied in a chair and commercialized.

This embodiment is made against the background of such a current situation, and is intended to provide an inner shell (and cushion material) entrainment structure from a different viewpoint from the above publication.

The seat depth adjustment mechanism in this embodiment can be generalized to exhibit various aspects. For example, for a seat, “a chair in which a seat cushion material is stretched on the surface of the seat inner shell, and the front portion of the seat inner shell is formed into a deformation allowing portion that can be wound downward together with the seat cushion material. The flexible member is arranged in an overlapping manner on the upper surface of the deformation-permitting portion of the seat inner shell with the operation portion exposed below the front portion of the seat inner shell, with the operation portion behind When pulled, the seat inner shell is wound downward via the flexible member. "

When this embodiment is applied to the backrest, “the back cushion material is stretched on the surface of the back inner shell, and the upper portion of the back inner shell is formed in a deformation allowing portion that can be wound back together with the back cushion material. In the chair, the flexible member is arranged on the front surface of the deformation allowing portion in the back inner shell in a state of having an operation portion exposed behind the upper portion of the back inner shell, and the operation portion Can be generalized as a configuration in which the back inner shell is wound back via the flexible member.

For the flexible member, for example, a linear form such as a string or a wire can be adopted. Moreover, the aspect which has considerable horizontal width is also employable.

In the above configuration, when the seat or the backrest is involved, the deformation allowing portion of the inner shell is bent and deformed while being pressed from the surface by the flexible member. For this reason, a deformation | transformation permission part can be bent equally over the whole. Therefore, the dimensional accuracy of the seat depth and the height of the backrest is excellent, and individual differences can be eliminated. Further, since the deformation permitting portion can be prevented from floating and bulging, the surface can be maintained in a beautiful state in a state where the depth of the seat is reduced or the height of the backrest is reduced.

Further, when the front end of the seat inner shell is pulled, the bending mode of the deformation permissible portion of the seat inner shell may not be constant, but as in the embodiment, when the portion behind the front end is pulled out of the seat inner shell, Since the bending fulcrum can be formed in the seat inner shell, there is an advantage that the seat inner shell can be beautifully wound. This point is an effect that is exhibited without being pulled by a flexible member such as a tape.

Adopting a tape-like flexible member as in the embodiment can reduce the area where the flexible member overlaps the deformation-allowing portion of the inner shell, thereby improving the adhesion and adhesion between the inner shell and the cushioning material. Can do. In particular, when the cushion material is bonded to the inner shell by insert molding, a high adhesive force can be secured, which is particularly beneficial. Further, if the flexible member is in the form of a tape, the pulling structure can be simplified (that is, it can be easily attached to the pulling member).

The present invention can be embodied in a chair. Therefore, it can be used industrially.

2 seats 3 backrest 9 fixed base 10 tilting base 11 pivot (locking fulcrum)
13 Back support frame 13a Back support 16 Seat inner shell 17 Seat cushion material 23 Back outer shell 23a to 23f Elements constituting the back outer shell 24 Back cushion materials 24a to 24f Elements constituting the back cushion material 30 Elements of the back cushion material Dividing groove 41 Elastic stopper 42 Back inner frame 43 Peripheral frame portion 44 Horizontal joint portion 45 Frame portion 55 Band hinge 46 Hinge portion 96 Groove that divides the elements of the seat cushion material

Claims (14)

1. A lockable backrest has a center area located in the middle in the left-right direction when viewed from the front, and side areas arranged on both the left and right sides of the center area, the side area being relative to the center area And can be bent in the longitudinal direction.
   A state in which the seater's load is not applied to the backrest at all is a neutral state,
   In the working state where only the lumbar part of the seated person hits the center area, the left and right side areas bend in the direction of wrapping the seated person from the neutral,
   When the seat occupant puts his back against the center area and the backrest locks, the left and right side areas bend in a direction away from the seat occupant based on the neutral state.
   Is set to make a movement,
   Chair.
2. The center area has a middle center element located above the waist of the seated person and a lower center element located below the middle center element, and the middle center element and the lower center element The shape of the mountain is configured toward the seated person's waist, and the middle center element and the lower center element are relatively rotatable so that the depression angle changes,
   When shifting from the neutral state to the office state, the side area wraps around the seated person in conjunction with the depression of the middle center element and the lower center element being pushed by the waist of the seated person to increase the depression angle formed by them. Set to bend,
   The chair according to claim 1.
3. The center area has a middle center element located above the waist of the seated person and a lower center element located below the middle center element, and the middle center element and the lower center element The shape of the mountain is configured toward the seated person's waist, and the middle center element and the lower center element are relatively rotatable so that the depression angle changes,
   In the locking state, the side area is set to expand and deform in a direction away from the seated person in conjunction with a decrease in the depression angle formed by the middle center element and the lower center element,
   The chair according to claim 1.
4. The backrest is connected to a back column so as to be able to rotate in the front-rear direction with a portion positioned above the waist of the seated person as a rotation fulcrum, and a portion of the backrest below the rotation fulcrum An elastic body that is elastically deformed by a change in the relative angle between the backrest and the back column is disposed between the back column and the back column,
   In the neutral state, the neutral state of the backrest is maintained by being in a reference state in which the elastic body is hardly or not deformed.
   When the backrest shifts from the neutral state to the working state, the elastic body is deformed in one direction from the reference state, and the included angle formed by the middle center element and the lower center element is increased, and each side is interlocked with this. While the area bends to reduce the included angle with the center element,
   If the body pressure of the seated person is strongly applied to the portion above the pivot point in the locked state, the elastic body is deformed in the other direction from the reference state, and the middle center element and the lower center element are formed. The depression angle is reduced, and in conjunction with this, each side area is bent to increase the depression angle with the center element.
   The chair according to claim 2 or 3.
5. The deformation of the elastic body includes a deformation in which expansion / contraction deformation and bending deformation are combined,
   The chair according to claim 4.
6. The lockable backrest has a center area located in the middle in the left-right direction when viewed from the front, and side areas arranged on the left and right sides of the center area,
   While the center area is composed of a plurality of center elements that are vertically connected in a bent posture in a side view,
   The side area is composed of a plurality of side elements that are vertically connected in a bent posture in a side view corresponding to the elements of the center area, and each element of the side area is in relation to the center area. In addition to being connected to bendable, the elements adjacent to each other in the vertical direction are also connected to bendable,
   When the backrest is locked by the seated person's backrest, each element in the side area bends away from the seated person so as to widen the depression angle with the element in the center area.
   Chair.
7. The center area and the side area are each composed of a three-stage element including a middle element, an upper element, and a lower element,
   By arranging the middle center element and the lower center element in a forward convex posture in a side view, a protrusion that supports the lumbar portion of the seated person is formed,
   The middle center element and the lower center element are relatively bendable, and the middle center element is held in an inflexible manner with the upper center element,
   The chair according to claim 1 or 6.
8. The backrest has a center area located in the middle in the left-right direction when viewed from the front, and side areas arranged on the left and right sides of the center area,
   While the center area is composed of a plurality of elements connected in the vertical direction with a bent posture in side view,
   The side area is composed of a plurality of elements connected in the vertical direction in a bent posture in a side view corresponding to the elements in the center area, and each element in the side area is bent with respect to the center area. Are connected to each other, and the elements adjacent to each other in the vertical direction are connected to each other so that they can be bent.
   According to the movement of the seated person, each element of the side area has a configuration in which the posture changes in the direction of wrapping the seated person, or the posture changes in the direction away from the seated person,
   Among the plurality of elements constituting the center area, at least two elements that are located above the waist of the seated person and are adjacent to each other in the vertical direction are non-bent elements that do not bend relatively. The element is connected to the non-bending element so that it can be bent.
   Chair.
9. The center area and the side area are each composed of a three-stage element including a middle element, an upper element, and a lower element,
   A lumbar support part that supports the lumbar part of the seating is formed by connecting the middle element and the lower element of the center area to a forwardly convex posture in a side view,
   The middle element and the lower element of the center area are bendable, and the middle element and the upper element are continuous so that they cannot be bent.
   The chair according to claim 8.
10. The backrest is provided with a cushion material that spreads over the entire surface thereof, the boundary portions of adjacent elements of the cushion material are partitioned by grooves, and the surface of each element is flat.
    The chair according to any one of claims 1, 6, and 8.
11. The seat has a seat cushion material that extends over the entire upper surface, and the cushion material is formed with a plurality of grooves that divide the cushion material into a plurality of elements in both the left-right direction and the front-rear direction. ,And,
    The pattern of the element in the back cushion material and the element in the seat cushion material are in a form close to symmetry,
    The chair according to claim 10.
12. A skin material is stretched on the surface of the back cushion material, and by fixing the skin material integrally to the back cushion material by insert molding, the skin material enters the inside of the groove and is stretched as a whole. Bonded to back cushion material,
    The chair according to claim 10.
13. The backrest includes a back outer shell constituting the back surface and a back cushion material constituting the front surface, and a groove is formed on the back surface of the back outer shell symmetrically with the groove of the back cushion material. ing,
    The chair according to claim 10.
14. The groove has a substantially V-shaped, substantially U-shaped or substantially trapezoidal cross-section in which the distance between the bottoms is narrower than the distance between the opening edges, and the depth dimension is about half the thickness dimension of the back cushion material. Set to
    The chair according to claim 10.

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