JP5771383B2 - Rocking chair - Google Patents

Description

  The present invention relates to a rocking chair having an elasticity adjusting device.

In many cases, the rocking chair supports the tilting of the backrest by an elastic means such as a spring or rubber, and the resistance to rocking can be changed by an elastic adjustment device. What is known as the elastic regulating device uses a coil spring or a torsion bar as an elastic means, by rotating operation of the screw type handle is intended to change the initial load on the coil spring or a torsion bar.

  Thus, when it is necessary to adjust the elasticity steplessly, the screw type handle is useful, but it cannot be applied to a simple method in which, for example, adjustment in two steps or three steps is sufficient.

On the other hand, the applicant of the present application disclosed a mechanism for changing resistance to rocking according to the weight of a seated person in Patent Document 1. That is, the thing of this patent document 1 uses the coiled spring and the movable rubber | gum fitted in this from a horizontal direction, and by making the dimension which rubber | gum fits into a coiled spring proportional to a seated person's weight, The total elastic restoring force of the coil spring and the rubber is automatically adjusted in proportion to the weight of the seated person.

Japanese Utility Model Publication No. 04-96254

  In Patent Document 1, the seat is configured to move down against the spring, and the fact that the size of the seat to move down against the spring is proportional to the weight of the seated person. The movement of rubber is linked. On the other hand, the strength (hardness) of resistance to rocking has a preference depending on the person, and some people prefer hard and some soft. Even the same person may have different preferences depending on mood and physical condition. Therefore, it can be said that there is a demand for an elasticity adjusting device that can be easily operated by a seated person.

  The present invention has been made in view of such a situation, and the mechanism for changing the elastic force of the elastic means is intended to provide a chair with higher reality while partially referring to the concept of 1 in Patent Document. Is.

The invention of claim 1 includes a base provided at the upper end of the leg, a seat disposed above the base, a back support device connected to the base so as to be tiltable rearwardly, and a backrest provided in the back support device; An elastic body that provides resistance to backward tilting of the back support device;
The elastic body, when the pressure area change a configuration the elastic restoring force changes, in the elastic member of the pressurizing varying the pressure area chair elasticity adjusting device that provided by lever operation,
The elastic body is arranged so as to be clamped from above and below by a rearward tilt of the back support device at a location away from the pivot point of the back support device, and by changing the clamping area in the vertical direction Elastic restoring force changes.

The present invention can be developed in various ways. For example, the invention according to claim 2 is the invention according to claim 1, wherein the elastic body is disposed behind the rotational axis of the back support device, and the lever is disposed behind the elastic body. ing.

According to a third aspect of the present invention, in the second aspect of the present invention , when the member or the elastic body that clamps the elastic body moves in the left-right direction, the clamping area of the elastic body changes.

According to a fourth aspect of the present invention, in any one of the first to third aspects, the elastic body can be clamped via a main elastic body that is pre-pressed before locking and a pressing member during locking. It consists of a sub elastic body,
When the pressing member slides, the sub-elastic body is switched between a pressurized state and a non-pressurized state, or when the sub-elastic body slides, the sub-elastic body is switched between a pressurized state and a non-pressurized state. Switch to state. Incidentally, the sub-elastic member may be a plurality stone by even one.

The present invention, depending on varying the pressure area of the elastic member in elastic adjustment device having a lever, which changes the resistance to locking, the elastic force of the elastic body is varied by a seat occupant operates the lever . Therefore, the adaptability to an actual chair is high.

By the way, when adjusting the elasticity only by changing the initial load on the elastic body such as a coil spring or rubber, the load per unit area (stress) on the elastic body is changed by adjusting the elasticity. Therefore, there is a possibility to progress faster or fart. This invention for the order in which varying the pressure area is changed elasticity unchanged the load per unit area with respect to the elastic body. Therefore, the load on the elastic body can be reduced and the durability can be improved, which is suitable when a rubber material is used as the elastic body .

When resistance is applied to rocking with an elastic body , if no resistance acts before rocking, there is a danger that a backrest will suddenly tilt backward when a person starts to lean. In this respect, in the configuration of claim 4, since the initial resistance is given by the main elastic body, the backrest can be safely locked.

When the main elastic body and the sub elastic body are provided, there are several methods for selecting the sub elastic body between the pressurized state and the non-pressurized state. However, if the structure is too complicated, the certainty of movement may be impaired. There is. In this regard, since the pressing member or the sub-elastic member in claim 4 is a simple method to slide, it can be secured the reliability of the motion.

Further, for example, is also contemplated that such arranging the main elastic body and the sub elastic member one by one, in this case, in a case where the combination of the case and the sub-elastic member using only the main elastic body, the entire elastic body Since the reaction point of the reaction force is deviated, the pressing member that presses the elastic body and the back support device may be twisted , which may reduce durability. On the other hand , when the sub-elastic body is arranged between the two main elastic bodies as in the embodiment, both the main elastic body and the sub-elastic body are used as the whole elastic body . since there is no possibility that the point of application of the reaction force is FIG increased, thereby improving its durability by eliminating twisting of the pressing member and the back support device.

(A) is a fragmentary perspective view of the chair which concerns on embodiment, (B) is a side view. FIG. FIG. It is the separation figure seen from the lower part. FIG. (A) is a partially separated perspective view of a movable rubber, (B) is a separated perspective view for showing a mounting structure of a back frame. It is a separate perspective view of the principal part. (A) is an exploded perspective view of the member, (B) is a perspective view with the receiving member turned upside down, and (C) is a partially broken perspective view of the base. FIG. It is a sectional side view in the location of fixed type rubber. (A) is a sectional side view at the location of the lock body, (B) is a sectional side view in a state where the movable rubber is disposed at a weak position. (A) is a separated plan view, (B) is a perspective view of the operation mechanism part. (A) is a perspective view of a back cover, (B) is a separated perspective view of an operation unit, and (C) is a partial perspective view of an operation mechanism section. It is sectional drawing which shows 2nd Embodiment. It is sectional drawing which shows 3rd Embodiment. It is the isolation | separation perspective view which shows 4th and 5th embodiment. It is a figure which shows 6th Embodiment.

Next, an embodiment of the present invention will be described with reference to the drawings. This embodiment is applied to a swivel chair used for office work or the like. In the following description, the use of the wording of the "before and after", "left and right" to identify the direction, this wording defines the direction a person is facing seated in a normal posture in a chair as before . The front view is viewed from the direction facing the seated person.

(1). Overview of the chair As shown in FIG. 1, the chair is composed of a leg device displaying only the leg strut (gas cylinder) 1, a base 2 fixed to the upper end of the leg strut 1, and a seat disposed above the base 2. It has a body 3 and a backrest 4 on which a seated person can rest. An armrest device can be attached to the base 2 as an optional item. As can be understood from FIG. 2, the seat body 3 has a seat plate (seat inner shell) 5 made of a synthetic resin and a cushion material 6 disposed on the upper surface thereof. The skin material is stretched.

As shown in FIG. 2, the backrest 4 is provided with a back frame 10 made of a synthetic resin, and a back plate 11 made of synthetic resin fixed to the front face. Back plate 11, the elongated holes has become form empty horizontal stripes in multiple stages, this skin material 12 such as a mesh is stretched. A cushion material may be disposed on the front surface of the back plate 11. In this case, the cushion material is covered with a bag-shaped skin material. The back frame 10 has a vertically long left and right side frame 13, an upper frame 14 that connects the upper ends thereof, and a lower frame 15 that connects the lower ends of the left and right side frames 13. A back plate 11 is fixed to the base plate.

The back frame 10 includes left and right forward arm portions 16 extending in series from the side frame 13, and a joint portion 17 having an upper plate 17 a and left and right side plates 17 b is integrally connected to the left and right forward arm portions 16. ing. A rocking member 18 made of a metal plate is connected to the rear part of the base 2 so as to be tiltable by a left and right longitudinal first shaft 19, and the joint portion 17 of the back frame 10 is fixed to the rocking member 18 with screws. ing. Right and left end portions of the first shaft 19 is exposed to the outside of the swinging member 18.

Accordingly, in this actual embodiment, the swinging member 18 and the back frame 10 and back support device is constituted by, backrest 4 around the first axis 19 is tilted (the first axis 19 of the backrest 4 pivoting It is a support shaft.) The swing member 18 and the back frame 10 can be configured integrally, the forward arm portion 16 can be a separate member from the side frame 13, or the swing member 18 and the forward arm 16 can be integrated. It is.

As shown in FIG. 3, the swinging member 18, the support arm 18a extending forward and upward in a side view inclined position is provided integrally, the tip of the left and right support arms 18a, the rear engagement pin 20 (FIG. 4) is inserted. For example, as shown in FIG. 5, the lower surface of the seat receiving body 7, a pair of left and right rear engaging claws 21 that caught fitted from behind the rear engagement pin 20 is integrally molded. For this reason, when the backrest 4 tilts backward , the seat support 7 and the seat 3 are pulled backward.

On the other hand, for example, as shown in FIG. 5, the base 2 is made of a metal plate and has a box shape with an upward opening having left and right side plates 2 a, and a horizontally elongated second shaft 22 at the front thereof. the attached, connecting the front link 23 unitary rotatably to the second shaft 22, and the upper end of the front link 23, female after having formed the seat receiving member 7 fitting portion 24 twice It is inserted in a movable manner. Accordingly, when the seated person leans on the backrest 4, the seat receiving body 7 is pulled backward by the swing member 18, and accordingly , the front link rotates and the seat portion 8 moves upward while moving upward.

As shown in FIG. 5, an upper cover 25 is mounted on the base 2 from above, and the rear engagement pin 20 is supported by the upper cover 25. The base 2 is covered with a lower cover 26 from below. A control unit 29 having an operation mechanism unit 27 and a back cover 28 is disposed at the rear of the base 2. By this control unit 29, switching of the resistance with respect to locking and regulation of the backward inclination of the backrest 4 are performed.

(2) Relationship between the base 2, the swinging member 18 and the back frame 10 Hereinafter, details of each part will be described. First, the relationship among the base 2, the swing member 18, and the back frame 10 will be described. As already mentioned, the base 2 is in the form of upwardly open box-shaped, for example, as shown in FIG. 5, the substantially central portion of which the inside of the base 2, a first inner shaped side section downwardly opening U A bracket 31 is welded, and a bush 32 is fixed to the inner bracket 31 and the bottom plate of the base 2, and the leg support 1 is fitted to the bush 32 from below.

As shown in FIGS. 5 and 7, the first inner bracket 31 has a U-shaped second inner bracket 33 that is fixed in an upward-opening shape, and an armrest device is installed in the space surrounded by the inner brackets 31 and 33. The proximal end portion is inserted from the lateral direction. Left and right end portions of the second inner bracket 33 is exposed to the outside of the base 2 forms a downward piece 33a at its distal end, downwards piece 33a, the base end portion of the armrest device is fastened with screws.

As shown in FIGS. 5 and 7, the swing member 18 is a basic form having an upper plate and left and right side plates 18b. The base 2 is enclosed from the outside by the left and right side plates 18b, and the left and right side plates 2a of the base 2 and the swing member. The first shaft 19 penetrates the left and right side plates 18b. The first shaft 19 is attached to the base 2 via a bush. The support arm 18a of the swing member 18 extends forward from the side plate 18b.

Left and right longitudinal frame receiving shafts 34 are inserted through the rear portions of the left and right side plates 18 b of the swing member 18. Both left and right end portions of the frame receiving shaft 34 are exposed to the outside of the swing member 18. On the other hand, for example, as shown in FIG. 4, the forward arm portion 16 of the back frame 10 has a thick-walled shape having a certain lateral width, the tip of the left and right forward arm portion 16, exposure of the first shaft 19 A forward opening groove 35 to be fitted into the end portion is formed, and further, a downward opening groove 36 to be fitted from the upper side to the distal end portion of the frame receiving shaft 34 is formed at a position behind the forward opening groove 35. .

As can be easily understood from FIG. 6B, the joint portion 17 of the back frame 10 overlaps the swing member 18 from above , and a resin-made pressing member 38 is provided on the lower surface of the swing member 18. overlapping. The three members are fastened together by screwing a screw 37 penetrating the upper surface plate 17a of the joint portion 17 and the upper surface plate of the swinging member 18 into the pressing member 38. As a result, the back frame 10 and the swing member 18 rotate together.

When locked , the rear engagement pin 20 is pulled backward by the rear engagement claw 21. When the locking is returned, the seat receiving body 7 must be pushed forward by the rear engagement pin 20. Therefore, although not shown, the seat receiving member 7, the stopper for holding the rear engagement pin 20 back and forth relative movement impossible, are mounted in a fitting from above.

(3). As shown in fixed arrangement embodiment example 10 of rubber, between the pressing member 38 and the base 2 are arranged right and left pair of stationary rubber 40 as an example of a main elastic body, The fixed rubber 40 is attached to a receiving member 41 attached to the base 2. Even in the non-locking state, the fixed rubber 40 is compressed by the pressing member 38 (the pressing member 38 and the receiving member 41 are pressed from above and below) . That is , a preload (pretension) is applied to the fixed rubber 40. Needless to say, the fixed rubber 40 and the receiving member 41 are arranged behind the pivot point of the swing member 18.

Fixed rubber 40 is forms a side view sector block shape, as shown by the dotted line in FIG. 10, and the upper surface 39a and lower surface 39 b, arranged to be positioned in the extension line of the axis of the first shaft 19 doing. For this reason, each part of the fixed rubber 40 is compressed evenly by the pressing member 38. In other words, the load caused by the pretensioning and locking act uniformly to each part of the fixed rubber 40. For this reason, durability can be improved by eliminating one-sided contact.

The receiving member 41 is made of resin, and has left and right fixed rubber mount portions 42 to which the left and right fixed rubbers 40 are attached, for example, as shown in FIG. Between the left and right fixed rubber mounts 42, a movable rubber pedestal 44 for receiving a movable rubber 43 (details will be described later) as an example of a sub-elastic body to make the resistance against locking strong. a movable rubber relief portion 45 for releasing as movable rubber 43 also locking is not compressed is formed in a state in which side-by-side.

As shown in FIG. 10, one that is on the bottom plate is approximately horizontal position of the base 2, a fixed rubber 40 is made substantially vertically symmetrical across a horizontal plane passing through the axis of the first shaft 19 in a side view Yes. For this reason , the fixed rubber mount portion 42 is inclined in a posture inclined backward with respect to the horizontal plane.

For example, as shown in FIG. 9, the fixed rubber mount portion 42 includes a rear rib 42 a for holding the fixed rubber 40 so that it cannot be displaced backward, a side rib 42 b and a rear rib 42 b for holding it so that it cannot be shifted left and right. However , it protrudes upward. The movable rubber cradle 44 is higher than the fixed rubber mount 42, and therefore the movable rubber cradle 44 serves as a stopper that prevents the inward movement of the fixed rubber 40. Accordingly, the left fixed rubber mount 42 has only one side rib 42b. On the other hand, the right side fixed rubber mount portion 42 has two left and right side ribs 42b.

For example, as shown in FIGS. 9 and 10, laterally long stopper pins 46 are interposed between the pressing member 38 and the fixed rubber 40 and between the fixed rubber 40 and the fixed rubber mount 42. A pin receiving groove 47 having a circular cross section is formed on the lower surface of the pressing member 38, the upper and lower surfaces 40a and 40b of the fixed rubber 40, and the upper surface of the fixed rubber mount portion 42 , respectively. Since the initial load is applied to the fixed rubber 40 even in the non-locking state, the stopper pin 46 does not come out.

As already mentioned, one is movable rubber cradle 44 is taller than the fixed rubber mount portion 42, as cut with understood from comparison of FIG. 11 (A) and (B), and a movable rubber The relief portion 45 is lower (deeper) than the upper surface of the fixed rubber mount portion 42. The bottom surface of the movable rubber relief 45 is also set so that its extension line passes through the axial center of the first shaft 19 or the vicinity thereof in a side view.

The receiving member 41 is a molded product of resin, and as shown in FIG. 8, a large number of ribs (or voids) are formed on the bottom. Further, as shown in FIG. 8B, the left and right positioning pins 48 project from the bottom surface of the receiving member 41 , while the positioning pins 48 are provided on the base 2 as shown in FIG. The fitting positioning hole 49 is opened. Therefore, receiving member 41 is held even impossible impossible falling displacement without screwing. Of course, fixing with screws is acceptable.

The pressing member 38 is a resin product and, as shown in FIG. 8, has a block-like appearance that is generally left-right longitudinal and close to a square, but has a number of voids for weight reduction. As shown in FIG. 11A, a screw 37 for fastening the joint portion 17 and the swing member 18 of the back frame 10 together is attached to a nut 50 ′ attached to the pocket portion 50 of the pressing member 38. Screwed in. Instead of using the nut 50, a female screw may be formed in the pressing member 38 and the screw 37 may be screwed directly into the female screw.

(4). Operation Unit Lock Switching Device Next, the operation unit 29 will be described. First, the lock switching device will be mainly described. As already mentioned, the operation unit 29 includes an operating mechanism 27, which is constituted by the rear cover 28 Toritsui.

For example, as shown in FIG. 13 (A), the rear cover 28 has a left and right rib plate side plate 28a, the elongated lateral Ataribu 28a, the clamping portion 28b for attaching the rear cover 28 to the frame receiving shaft 34 Open forward. The sandwiching portion 28b is fitted into the frame receiving shaft 34 by being deformed against elasticity.

For example, as shown in FIG. 11B , the back cover 28 is provided with a flange portion 28c that overlaps the upper surface of the rear portion of the swing member 18, and the flange portion 28c is attached to the upper surface plate of the swing member 18 with a screw 51. It is fixed. A recess 52 for accommodating the head of the screw 51 is formed in the collar portion 28c.

For example, as can be appreciated FIG. 12 or, et al., The operation mechanism unit 27 includes a central axis 54, and an outer cylinder 55 for covering the same. The central shaft 54 constitutes an elasticity adjusting device, and one end (right end) thereof protrudes outside the outer cylinder 55, and a strength adjusting lever 56 is attached to the protruding portion .

On the other hand, the outer cylinder 55 constitutes a lock switching device, and a lock lever 57 is provided at one end (right end) thereof. Both levers 56 and 57, strength adjusting lever 56 is arranged so as to lock lever 57 with the outside is located inside. Further, the levers 56 and 57 are arranged with different postures in a side view so that a person can easily operate them. One end portion of the outer cylinder 55 is a large diameter portion 55 a, and the shaft portion of the strength adjustment lever 56 is rotatably held by the large diameter portion 55 a , and the central shaft 54 is the axis of the strength adjustment lever 56. The part is fitted so as not to be relatively rotatable.

For example, as shown in FIG. 9, on the left and right side end surface of the rear cover 28, and provided with a side plate 28d that protrudes forward in the order of upper half thereof, the inside of the side plate 28d, forward projecting outer rib 28a described above doing. The side plate 28d overlaps the side plate 17b of the joint portion 17 in the back frame 10 from behind.

For example, as shown in FIG. 13, a lock body 59 protruding from the axial center is integrally provided at the end of the outer cylinder 55 opposite to the lock lever 57, and the back cover 28 has a lock body 59. the forming the inner ribs 60 that sandwich from the left side, the inner end portion 55b of the outer tube 55, which is fitted to the bearing hole 61 formed on the inner rib 60. That is, the base portion of the lock body 59 is surrounded by the outer rib 28 a and the inner rib 60 from both the left and right sides. One outer rib 28a is formed with an engaging slot 62 into which the other end 55c of the outer cylinder 55 is fitted. The engagement slot 62 has a narrow shape with a narrow opening.

As shown in FIG. 13, the other end portion 55 c of the outer cylinder 55 is formed with a Nusumi groove 63 having a flat outer peripheral surface, and the outer cylinder 55 has the Nusumi groove 63 parallel to the engagement groove hole 62. by the, can be fitted to Kakarigomizoana 62, and is rotated to the use position from the fitted, it is missing non retained. A stopper piece 64 that prevents the outer cylinder 55 from moving inward is formed at the other end 55 c of the outer cylinder 55.

As shown in FIG. 13C, the lock body 59 has a posture that protrudes substantially downward from the outer cylinder 55, and includes two first and second step portions 65 and 66 facing the base 2. Has a step. The 1st step part 65 is located in the front end side. On the other hand, first to fourth engagement grooves 67a to 67d are formed on the back surface of the lock body 59, and a stopper 68 is selectively fitted from behind to the engagement grooves 67a to 67d. It is supposed to be. As shown in FIG. 13 (B), the stopper 68 is mounted in a state that only longitudinal movement in the pocket portion 69 formed in the rear cover 28 is urged in the forward direction by the rubber 70. As shown in FIG. 11A, an inward rib 71 that abuts against the central shaft 54 from the outside is provided at the other end of the outer cylinder 55 to ensure stable rotation.

As can be understood from FIG. 11 (A), the locking member 59 is outwardly supporting flange 2c provided in the back wall 2b of the base 3 so as be in contact from above. In FIG. 11A , the first step portion 56 of the lock body 59 is in a locked posture facing the upper surface of the support flange 2c. In this state, the backrest 4 is in a completely locked state in which the backrest 4 hardly tilts backward. . Further, the stopper 68 is fitted in the second engagement groove 67b , so that the lock body 59 is held in the posture.

Is rotated from the state shown in FIG. 11 (A) to the outer tube 55 anticlockwise, the locking member 59, and an intermediate position in which the second step portion 66 is opposed to the support flange 2c, the second step portion 66 supporting flange 2c Switch to a free posture facing the outside. In the intermediate posture, when the backrest 4 is tilted to a range of about half of the maximum tilt range, the second step portion 66 comes into contact with the support flange 2c, thereby restricting the back tilt range of the backrest 4 to about half of the maximum stroke. . In this intermediate posture, the stopper 68 is fitted in the third engagement groove 67c.

Further, in the free position, not the lock body 59 when locking strikes the support flange 2c, Therefore, the backrest 4 is free to tilt by up tilt range. In this free state, the stopper 68 is fitted in the fourth engagement groove 67d.

(5) Elasticity adjusting device in the operation unit Next, an elasticity adjusting device for moving the movable rubber 43 in the operation mechanism unit 27 will be described. As described above, the elasticity adjusting device has the central shaft 54. For example, as can be understood from FIG. 13B , the front end portion of the central shaft 54 is supported by the other outer rib 28a of the back cover 28, and a snap ring 73 is attached to the front end to prevent it from coming off. . In the center shaft 54, between the inner rib 60 of the back cover 28 and the other outer rib 28a, for example, as shown in FIG. 9 and FIG. The cam 75 is fitted.

Slider 74, when being fitted slidably in the central shaft 54 has forward projecting both are arranged a movable rubber 43 on its lower surface. Further, the slider 74 is open downward, Therefore, the movable rubber 43 is held so as not to shift in the lateral direction and longitudinal direction. Further, as shown in FIG. 13 (B), while forming a groove 43a on one side of the movable rubber 43, the slider 74 forms a full rib fitting into the groove 43a (not shown) This prevents the dropout.

As shown in FIG. 11 (B), the slider 74 and the movable rubber 43 is fitted freely right and left slide in the cavity 76 formed in the pressing member 38. The movable rubber 43 also has a fan- like shape in a side view like the fixed rubber 40 . Also, while that in the front end of the slider 74 is provided with two left and right guide protrusions 77 (see also FIG. 9 and 12), the front end portion of the pressing member 38, the guide projection 77 fits the guide grooves 78 (FIG. 8 ( a) are also provided a reference), Thus, the slider 74 and the movable rubber 43 is stably horizontally slide without touching down. The guide means may have another structure.

For example, as shown in FIG. 12, the slider 74 includes a full cylindrical body 79 fitted on the central shaft 54 has a casing 80 surrounding this, case section 80 includes a rib 82 formed on the rear cover 28 ( The group shown in FIG. 13A is slidable to the left and right. The case portion 80 is urged toward the strength adjustment lever 56 by a spring 83 .

Then, as shown in FIG. 12, the cylindrical body 79, while the female cam groove 84 extending spacing toward the strength adjustment lever 56 in a plan view, are thus formed to make a rib, actuating cam 75 Is a bifurcated shape arranged so as to hold the cylindrical body 79 from the outside, and has a cam surface 84 a that is tapered in plan view and overlaps with the female cam groove 84. The operating cam 75 is fixed to the central shaft 54 so as not to rotate relative to the central shaft 54 or to slide.

  Therefore, when the strength adjustment lever 56 is rotated, the slider 74 moves left and right by the guide action of the operating cam 75 and the female cam groove 84. A stepped portion 85 that engages with the opening edge of the female cam groove 84 is formed at the tip of the operating cam 75. The stepped portion 86 is an example of a locking unit that holds the operating cam 75 in a non-fitted state with the female cam groove 84.

As shown in FIG. 12A, in the retracted state in which the operating cam 75 is fitted in the female cam groove 84, the slider 74 is held in the fitted state by the spring 83. In this state, the movable rubber 43 is located above the movable rubber relief 45 in the receiving member 41, and therefore the movable rubber 43 does not act as a resistance when locking. That is, the elasticity adjusting device is in a weak state where resistance to rocking is small.

Then, when the operating cam 75 is rotated in the direction of the arrow in FIG. 12B with the slider 74 retracted, the slider 74 is pushed away from the strength adjustment lever 56 against the spring 83, and the operation is performed. As the step portion 85 of the cam 75 abuts against the opening edge of the female cam groove portion 84, the slider 74 is held in the advanced state. In this advanced state, the movable rubber 43 is located above the movable rubber cradle 44, thus, moveable rubber 43 acts as a resistance during locking. That is, the elasticity adjusting device is in a strong state with a large resistance when rocking.

As shown in FIG. 12 (B), the base end portion of the actuating cam 75, as in the tangential direction shown in FIG. 12 (A) in a state where the slider 74 is retracted not rotated, female cam in the slider 74 A restricting portion 86 that contacts the opening edge of the groove portion 84 is provided. On the other hand, the rear cover 28, closes the swinging member 18 from behind. Therefore, as shown in FIGS. 5 and 7, the left and right side plates 18 b of the swing member 18 are provided with relief grooves 87 into which the outer cylinder 55 of the operation mechanism portion 27 is fitted.

(6) Summary As described above, by rotating the strength adjusting lever 56 and moving the slider 74 to the left and right, the movable rubber 43 moves to the left and right to shift between the pressurized state and the non-pressurized state. Thus , the resistance to rocking is adjusted in two steps. Since the strength is adjusted by such a simple movement of the slider 74, the operation is reliable.

  In addition, since the movable rubber 43 is disposed between the left and right fixed rubbers 40, there is no change in the point of reaction force acting on the pressing member 38 in the state where the movable rubber 43 is pressed or not. For this reason, the connecting portion between the swing member 18 and the first shaft 19 is not twisted.

As in the present embodiment, when the stopper pin 46 is interposed between the fixed rubber 40 and the pressing member 38 and receiving member 41, and reliably prevent the displacement of the fixed rubber 40 during locking, fixed rubber There is an advantage that 40 can be compressed into a uniform state. The advantages of forming the fixed rubber 40 and the movable rubber 43 in a fan shape when viewed from the side have already been described.

  Further, when the movable rubber and the lock switching device are incorporated in the operation unit 29, the seated person can perform the elasticity adjustment and the lock switching with one hand, so that the operability is excellent. Further, if the center shaft 54 is used as an elasticity adjusting device and the outer cylinder 55 is used as a lock switching device, the slider 74 can be slid easily, and the outer cylinder 55 having a large outer periphery receives a rocking load. Excellent strength.

When fastened tripartite between the joint portion 17 and the swing member 18 and the pressing member 38 of the back frame 10, it can contribute to cost reduction by suppressing the number of parts. Furthermore, when held slidably the slider 74 to the pressing member 38, as described above, the intensity adjustable reliabilized to prevent touching and below the slider 74.

Instead of using the movable rubber 43, it is also possible to attach an intermediate fixed rubber corresponding to the movable rubber 43 to the receiving member 41 and move the slider 74 to a position where it does not contact the intermediate fixed rubber. is there. In this case, needless to say, the pressing force of the swinging member 18 acts on the intermediate fixed rubber via the slider 74 (even if it is called a movable pressing member) (also in the above embodiment, the swinging force is applied). The pressing force of the member 18 acts on the movable rubber 43 via the slider 74).

(7). Other Embodiments FIG. 14 and subsequent drawings show other embodiments of the elasticity adjusting means. Among these, in the second embodiment shown in FIG. 14, one fixed rubber 90 is arranged on the receiving member 41, and the fixed rubber 90 is divided into three left and right by a groove 91, so that the left and right of the fixed rubber 90 are left and right. sites at both ends, forms a constantly acting portion 90a which is fixed pressing member 38 is always in contact with the left and right intermediate portions, it forms a regulating portion 90b which movable pressing member 38b is run away or contact. The movable pressing member 38 is switched between a state of being overlapped with the adjusting portion 90b and a state of being escaped by moving in a direction perpendicular to the paper surface by an operation of a lever or the like.

In the third embodiment shown in FIG. 15, a compression coil spring is used as the elastic body. In this embodiment, it is used three spring arranged in left and right directions, right and left sides of the spring, constantly acting spring 91 ungated to fixed pressing member 94 is always in contact with the intermediate spring is adjusted spring 93.

  Then, a movable pressing member 95 that moves in a direction perpendicular to the paper surface is attached to the fixed pressing member 94, and the adjusting spring 93 is compressed by moving the movable pressing member 95 by operating a lever or the like. It is designed to switch between a state and an uncompressed state. A hole 96 for allowing the adjustment spring 93 to escape when the fixed pressing member 94 moves downward is provided in the fixed pressing 94.

FIG. 16A shows a fourth embodiment. In this embodiment, an intermediate fixed rubber 97 is disposed between the left and right fixed rubbers 40. The left and right fixed rubber 40, the fixed pressing member similar to the first embodiment is always in contact. Then, by forming the back of the pressure receiving surface of the intermediate fixed rubber 97 stepwise, the pressure-receiving surface movable pushing member (not shown) strikes, is set to a small area portion 97a and the large-area portion 97b Yes.

Movable pressing member, by sliding in the lateral direction, for example, a mini-state contact with a small area portion 97a, and a state in contact with only the large-area portion 97b, extend over a small area portion 97a and the large-area portion 97b It is possible to switch to the three stages of the state of being in contact with each other. As a result, the area where the movable pressing member abuts against the intermediate fixed rubber 97 changes in three stages, and the elastic force against locking is adjusted in three stages. It is also possible to switch in two steps in contact with the one of the small area portion 97a and the large-area portion 97b.

In the fifth embodiment shown in FIG. 16 (B), the pressure receiving surface 97c of the intermediate fixed rubber 97, longitudinal width toward the other from its one end, continuously varied movable pressing member 95, The handle 99 can be held at an arbitrary position by rotating the handle 99. That is, a screw cylinder 103 that is rotated by a handle 99 is screwed into the base 100 of the movable pressing member 98, and the screw cylinder 103 is held in a non-slidable manner by holding means (not shown). Accordingly, the position of the movable pressing member 95 can be adjusted steplessly by rotating the handle 99, and as a result, the elastic force of locking can be smoothly adjusted steplessly.

The longitudinal width of the pressure receiving surface of the intermediate fixed rubber 97 may be changed in multiple stages of three or more stages. Further, even when the longitudinal width of the pressure receiving surface 97c of the intermediate fixed rubber 97 is continuously changed as shown in FIG. 16B, the position of the movable pressing member 95 is adjusted in three steps. Is possible.

FIG. 17 shows a sixth embodiment. In this embodiment, a movable pressing member 98 is slidably disposed between two left and right fixed rubbers 40 so as to be slidable left and right. The first movable rubber 104 and the second movable rubber 104 are arranged on the movable pressing member 98. ', And T-shaped pressure receiving bodies 105 and 106 having leg-like contact portions on the lower surface portions of the movable rubbers 104 and 104' are provided by bonding or the like.

The movable pressing member 98 includes a foot-shaped first movable stopper 107 positioned between the two movable rubbers 104 and 104 ′ and a foot-shaped second movable rubber positioned outside the second movable rubber 104 ′. A stopper 108 is provided. Lower ends of the stopper 107 is adapted to lower substantially the same height of the two pressure receiving body 105, 106.

The movable stopper 107 and 108 is formed on the movable pressing member 98, the two pressure receiving body 105 is integrally attached to the movable pressing member 98. Accordingly, the movable stopper 107 and the movable rubber 104, 104 ', be unitized influence slides with movable pressing member 98. In this embodiment, the unit can be selectively moved to the four positions (A) ~ (D) of FIG. 17.

17A shows a locked state in which the backrest does not tilt backward. In this state, both the movable stoppers 107 and 108 project upward from the receiving member 41 and the second supporting portion 108 and the second supporting portion 108 are provided. Abuts against the support 109. Next, in the state shown in FIG. 17B, both movable stopper portions 107 and 108 are disengaged from both support portions 107 and 108, and the two movable stopper bodies 107 and 108 can freely move downward. It has become. Therefore, in this state (B) , the back tilt of the backrest is supported only by the left and right fixed rubbers 40.

In the state shown in FIG. 17 (C), the two movable stoppers 107 and 108, the first movable rubber 104 can freely falling movement together, such that the second pressure receiving member 106 abuts against the first supporting portion 109 Therefore, the second movable rubber 104 ′ is also compressed and deformed by locking. In the state shown in FIG. 17D, both the movable stoppers 107 and 108 can freely move downward, the first pressure receiving body 105 contacts the third support portion 111 of the receiving member 41, and the second pressure receiving body 106 is Abuts on the first support portion 109. Thus, in the state of (D), both the moveable rubber 104, 104 'of compressive deformation by the locking.

  In the embodiment of FIG. 17, since the locking means and the elasticity adjusting means are incorporated in one unit, the structure can be simplified accordingly. It is also possible to reverse the movement of the member from that in FIG. That is, it is also possible to slide the support portions 109, 110, 111 with the movable rubbers 104, 104 ′ and the movable stoppers 107, 108 fixed.

(7). Others The present invention can be embodied in various ways other than the above embodiment. For example, it goes without saying that the present invention can be applied to a chair in which the seat portion does not move up and down during locking. It is possible to change the elasticity to three or more levels, or to change the elasticity steplessly. For example, take an example of the above embodiment, as a method of slider 74 is moved to the left and right both sides of the neutral position, the elastic force of the sub elastic body when moving to the right and left one side of, is moved to the other It is possible to adjust in three stages by making the elastic force of the elastic body of the sub-elastic body different from the above.

The specific form and structure of the operation unit can be set as required. It is also possible to integrate the operation mechanism unit and the back cover. Elastic regulating device only, or it is also possible to unit the only lock switching device. The lever is not limited to the rotation (rotation) method, and other operation modes such as a push method can be adopted.

The chair to be applied is not limited to a swivel chair, but can be applied to a non-lifting chair such as a conference chair or a fixed chair such as a theater chair. Elasticity adjusting device, it is not always necessary to use a slider to move laterally. When using a slider, it is not always necessary to employ the cam means as in the embodiment. When the cam means is employed, a circumferential cam can also be employed.

  The present invention is embodied in a chair and exhibits its usefulness. Therefore, it can be used industrially.

1 Leg support (gas cylinder)
DESCRIPTION OF SYMBOLS 2 Base 3 Seat body 4 Backrest 7 Seat receiving body 10 Back frame 16 Backward-facing arm part 18 Swing member 19 1st axis | shaft 17 Joint part 27 Operation mechanism part 28 Back cover as an example of support material 29 Operation unit
38 A pressing member constituting an elastic adjustment device 39 A fixed rubber as an example of a main elastic body 41 A receiving member 43 A movable rubber as an example of a sub elastic body 56 A strength adjustment lever constituting an elastic adjustment device 57 A lock lever 74 An elastic adjustment Slider constituting the device

Claims (4)

A base provided at an upper end of the leg; a seat disposed above the base; a back support device connected to the base so as to be tiltable rearwardly; a backrest provided on the back support device; and a rear tilt of the back support device An elastic body that provides resistance to
The elastic body is compressed when the pressure area is changed are configured to elastic restoring force changes, a chair elastic adjustment device by lever operation changing the pressure area of the elastic body that is provided,
The elastic body is arranged so as to be clamped from above and below by a rearward tilt of the back support device at a location away from the pivot point of the back support device, and by changing the clamping area in the vertical direction The elastic restoring force changes,
Rocking chair. The elastic body is disposed behind the pivot axis of the back support device, and the lever is disposed behind the elastic body.
The rocking chair according to claim 1. When the member or elastic body that clamps the elastic body moves in the left-right direction, the clamping area of the elastic body changes.
The rocking chair according to claim 1 or 2. The elastic body is composed of a main elastic body that is pre-pressed before locking and a sub-elastic body that can be clamped via a pressing member during locking,
When the pressing member slides, the sub-elastic body is switched between a pressurized state and a non-pressurized state, or when the sub-elastic body slides, the sub-elastic body is switched between a pressurized state and a non-pressurized state. Switched to the state,
The rocking chair according to any one of claims 1 to 3 .

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