JPH0734615Y2 - Height adjustment device for swivel chair height - Google Patents

Description

[Detailed description of the device]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lift for a swivel chair, and in particular, it prevents tightening and developing, does not change the adjusting position, and enables easy assembly by using a clip, thereby improving productivity and productivity. The present invention relates to a height adjusting device for a chair that can improve the productability.

[0002]

2. Description of the Related Art A rotary chair lift is an adjusting device for appropriately adjusting the height of a seat board according to the physical condition of the user, and various kinds of such adjusting devices are currently being developed and used.

As an example, a telescopic method and a screw method are mainly used. Such an adjusting device is generally installed upright between the seat and the legs of the chair,
The height of the target chair is adjusted by additionally providing it to the column that provides the height of the seat board. Such stanchions typically hold a stanchion pipe and a seating board within the stanchion pipe,
It is composed of a cylinder pipe that is fitted and coupled so as to be able to freely move up and down, and a height adjusting device is additionally provided in the pillar body to perform its preparation work.

The adjusting device thus provided has a clutch function for connecting and disconnecting the screw shaft and power transmission in the cylinder pipe of the strut, and a mechanical element such as a spring for restoring the clutch to the original condition for adjusting the height. ing.

More specifically, the lifting force transmission is interrupted by the clutch function by utilizing the difference between the load values when a seating load is applied to a seat of a chair and when the seating load is not applied. When the seating load is applied to the chair, the cylinder pipe descends and at the same time the spring contracts and the clutch structure that is screwed to the screw shaft is released, the nut clutch is separated from the cylinder pipe, and the rotational force of the seat plate causes the nut clutch to move. When the chair is not seated on the chair, that is, when the load is removed, the chair is lowered by the restoring force of the spring. The cylinder pipe has been restored to the current state and the clutch structure has been combined, and the nut clutch and the cylinder pipe have become integral and the rotational force of the seat plate has been changed. It is transmitted to the nut clutch through the pipe, and the rotational force transmitted in this way rotates the nut clutch and the nut clutch moves up and down on the screw shaft to adjust the height of the target chair. There is. For example, Utility Model Publication Sho 55-348
46 and U.S. Pat. No. 3,991,965.
However, such an adjusting device raises the cylinder pipe by the restoring force of the spring as described above when the seating load is removed from the seat plate. If it is rotated in the direction, the rotational force of the seat plate is transmitted through the cylinder pipe and the nut clutch rides on the screw along the direction of rotation to move up and down to adjust the height of the chair. If the nut clutch reaches the uppermost end or the lowermost end of the screw shaft by the operator's carelessness and the seat plate is rotated further, the nut clutch will cause a tightening phenomenon at the uppermost and lower end parts of the screw shaft. However, when releasing the nut clutch to which such a tightening force is applied, an instantaneous impact is applied to the nut clutch in the reverse tightening direction. There is also to be solved Ete, in order to give the impossible to the machine element, it becomes a factor of damage.

If the seat is loaded on the chair and the clutch structure is released, the nut clutch is left in a free state. At this time, if external shock or vibration is applied to the chair, the nut clutch is screwed to the screw shaft. The nut clutch cannot maintain the adjusted current position, and it is gradually moved to change the height adjustment position of the chair, and the adjustment height changes every time when sitting on the chair, and it is necessary to perform the adjustment work again. is there. In other words, there is a drawback that the adjustment state of the chair is not stable.

In order to solve the above problems, a washer is provided below the thrust bearing interposed between the nut clutch and the spring, and a storage groove opened upward is formed inside the nut clutch. A rubber O-ring is provided on the upper surface of the storage groove so that a part of the rubber O-ring is pushed up. When the rubber O-ring is pressed by the expansion pressure of the spring transmitted through the washer, it is generated when the inner diameter of the O-ring contracts. A rotating chair up-and-down adjusting device provided with a tightening component that bites the screw shaft by tightening force and fixes the nut clutch so that it does not easily move is being developed and used (Korea utility model publication number 91-5145). Although such an up-and-down adjustment device is somewhat effective in preventing the clutch from moving, the tightening force of the rubber O-ring is remarkably strongly applied to adjust the height. Lifting regulation of Ttokuratchi there has been a drawback that hard.

As described above, since a washer (support ring) for pressurizing and expanding the rubber O-ring must be provided on the upper side of the nut clutch (height adjusting tool), the mechanical element is In addition to the drawback that the installation space is increased and the apparatus becomes large, the material cost and the assembly man-hour increase, which is an obstacle to improving the productivity.

Since the pressure expansion value of the O-ring is made different depending on whether or not the seating load is applied, the tightening force or the seating load action causes the seating load to be slightly different. In the released state, the tightened state of the O-ring is released, and when an external force is applied, the nut clutch is gradually moved by the screw, and the movement may even change the adjustment position. Further, a hexagonal nut for restraining loosening for automobiles, which suppresses unraveling of the nut through a ring (synthetic resin) having a large nut friction resistance coupled with a screw shaft (bolt), is already well known.

Therefore, a simple structure is provided in which a clutch groove is provided in the center of the inside of the nut clutch screwed to the screw shaft and the rubber ring is fitted into the groove. The applicant previously applied for a height adjusting device for a swivel chair that is smooth.

On the other hand, in the adjuster, the screw shaft that directly provides the height of the chair is prevented from rotating in the axial direction on the bottom surface of the strut pipe and in a direction intersecting with the axial length in an idle manner. The fixing method is such that a screw rod having a predetermined diameter is integrally provided at the terminal end of the screw shaft, and the screw shaft rod extends outward through a hole formed in the center of the bottom of the strut pipe. After protruding, the projecting rod and the bottom surface of the support pipe are welded to the outside.

However, such a fixing method inevitably requires a welding process, which increases working time and labor,
Not only manufacturability but also mass productivity is hindered, and when the parts are partially damaged, that is, when the screw thread of the screw shaft is damaged, it is uneconomical to replace the strut pipe itself. There was a problem.

[0013]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object thereof is to provide a simple and effective height adjusting device for a swivel chair that does not cause a nut clutch tightening phenomenon. That is.

Another object of the present invention is to provide a height adjusting device for a swivel chair in which the height adjusting position of the chair is accurately maintained.

Another object of the present invention is to provide a height adjusting device for the height of a swivel chair, which simplifies the constituent elements to improve the manufacturability as well as the merchandise property and at the same time can repair the parts. .

[0016]

This and other objects of the invention are accomplished by providing a swivel chair lift, or swivel chair lift adapted for use with a clutch.

That is, the height adjusting device for the height of the swivel chair of the present invention interposes a strut having a constitution in which the strut pipe and the cylinder pipe are fitted and joined by a strut pipe and a cylinder pipe so as to extend and contract, between the leg and the seat plate. A bush, a washer, a second spring, a sleeve, and a thrust bearing are provided from the upper side in the cylinder pipe of this strut, and a seat plate is seated on a screw shaft that passes through the center of these and is hung on the strut pipe and the cylinder pipe. In a height adjusting device for the height of a swivel chair equipped with a clutch unit in which a groove and a protrusion are coupled and released by a load being applied or not applied, a vertical portion of the groove of the nut clutch of the clutch unit. When,
The convex portion of the clutch plate is characterized in that it is provided with an inclined portion so that the nut clutch is idly rotated by providing a slip when the abnormal external force acts to release the clutch unit, thereby achieving the above object. To be done.

This lift has a strut pipe and a cylinder pipe which are connected so as to freely extend and contract, and have a screw shaft in the center, and in the cylinder pipe, first and second springs, sleeves, It is equipped with a thrust bearing and a clutch unit that can adjust the height of the chair and connects and disconnects power transmission.

The clutch unit is composed of a nut clutch and a clutch plate which are separately coupled with each other, and a vertical groove and an inclined section are provided in a concave groove formed in the nut clutch of the clutch unit. It is provided with obtuse corners that cause slippage and automatically release the clutch function when an abnormal external force is applied to the part where the parts hit.
Then, the nut clutch is provided with a chamber having a predetermined size, an O-ring for retaining the nut clutch by engaging the screw shaft is provided in the chamber, and the screw shaft is easily fitted by a strut pipe and a clip. It is fixed to the joint.

Therefore, the tightening phenomenon of the nut clutch can be prevented, the adjusting position can be stably and strongly fixed, and the parts can be partially replaced.

[0021]

Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 shows a swivel chair provided with a height adjusting device of the present invention. The chair has a leg (10) having three or four legs and a seat plate (back) having a rear portion. 20)
And a strut for maintaining a space between the leg (10) and the seat plate (20).

FIG. 2 shows the structure of the support column in detail.

The stanchion is composed of a stanchion pipe (1) and a cylinder pipe (2), and the length of the stanchion can be freely extended and contracted so that the seat plate (20) can be seated.

An adjusting device is additionally provided on the column of such a swivel chair, and the height adjustment work of the target chair is performed.

More specifically, in the pillar pipe (1) having a substantially tubular shape which is vertically fixedly installed on the upper surface of the center of the leg (10), a taper shape in which an upper end portion is gradually narrowed upward A seat plate (2
A cylinder pipe (2) on which 0) is connected and fitted is provided so as to be freely adjustable up and down. In the cylinder pipe (2) thus installed, the first spring (51), the bush (3), and the washer (4) from the upper side.
And a second spring (5) are sequentially provided, and a sleeve (6) and a thrust bearing (7) are sequentially provided on the lower side thereof.

At this time, the first spring (51) housed on the upper side of the cylinder pipe (2) absorbs and absorbs an external shock to reduce the shock applied to the joints of the upper and lower ends of the column. Play a role.

A nut clutch (9) is detachably engaged with a clutch plate (8) integrally fixed to the lower end of the cylinder pipe (2) at the lower portion of the thrust bearing (7). The screw shaft (11) is provided in a screw connection type, and the screw shaft (11) has a bush (1a) at an upper end and a flange-shaped bush (3) described below at a lower end.
0) is used to support the support pipe (1) and the cylinder pipe (2).

In other words, the upper end of the screw shaft (11) is freely rotatably fitted to a bush (1a) integrally fixed to a washer (4) provided on the upper middle side of the cylinder pipe (2). Flange type bush (30), which is connected and the lower end of which is installed on the bottom of the pillar pipe (1)
It is fixedly installed in. And, the thrust bearing (7) provided between the sleeve (6) and the nut clutch (9) provides sliding so as not to be interfered with each other by the sleeve (6) and the nut clutch (9).

The second spring (5) provided between the bush (3) and the sleeve (6) in the cylinder pipe (2) has a washer (4) provided on the upper side in the support pipe (1). It has a proper upward elastic force that holds the clutch plate (8) with the nut clutch (9) at the same time as pushing up the own weight of the seat plate for holding up and eliminating the seating load.

Such a spring ( 5 ) contracts when a seating load is applied to the seat plate (20) of the chair, and returns to the current state when the seating load is removed, that is, the spring ( 5 ) is extended and a strut pipe is used. It automatically engages (1) and provides a mating connection between the nut clutch (9) and the clutch plate (8) for adjusting the seating height of the chair, described below.

FIG. 3 shows the structure of the nut clutch in detail.

The nut clutch (9) constitutes a substantially circular ring-shaped O-ring by forming a square space of an appropriate size released inwardly toward the inside, that is, on the upper side of the inner peripheral wall where the spiral wire is provided. An empty room (92) for accommodating (91) is formed. At this time, the O-ring (91) has a thickness such that the O-ring (91) is forcibly inserted into the inner wall of the chamber and is tightly inserted, and the outer diameter of the O-ring (91) is substantially the same as the peripheral wall of the chamber. Then
The screw shaft (11) is forcibly inserted and assembled with its inner diameter being slightly smaller than the outer diameter of the screw shaft (11). At this time, the O-ring (91) has an appropriate cushioning property and accommodates the screw shaft (11), and
The tooth crest of 1) is received deeply and an appropriate pressure is applied to the tooth crest of the screw shaft (11) to provide the screw shaft (11) with a constant and stable biting force.

The upper surface of the nut clutch (9) is provided with a force for holding the spring (5), the sleeve (6) and the thrust bearing (7) in an area where they are mounted. Such forces provide the height of the seat (20) of the chair.

The nut clutch (9) of the adjusting device thus constructed provides the seating height of the seat plate (20) and is seated at a position where it is stopped at a certain point of the screw shaft (11). The nut clutch (9) for accommodating a load is preferably manufactured by using a material having excellent strength.

FIG. 4 shows in detail the mutual coupling structure of the clutch plate (8) and the nut clutch (9), which are the main components of the adjusting device.

That is, at least one concave groove (93) is provided on the bottom surface of the nut clutch (9) with an appropriate interval.
The vertical groove (93) is provided on both side walls of the groove (93).
1) and an inclined portion (932). The groove (9
The vertical portion (931) of 3) has a height of about 3/1 of the total length of the concave groove of the nut clutch (9), and the other 3/2 is an inclined portion (932).

The groove (93) having such a structure has a convex portion (81) protruding upward from the upper surface of the clutch plate (8).
A clutch function is provided by providing a receiving space to be fitted and coupled.

More specifically, the concave groove (93) is composed of vertical and inclined portions (931) and (932), and an obtuse angle is formed at a point where the vertical and inclined portions (931) and (932) meet each other. It provides a corner (933). Such a corner (933) is formed on the upper surface of the clutch plate (8) by the groove (9).
3) It comes into contact with an appropriate position below the apex of the semi-circular arcuate convex portion (81) provided corresponding to 3) and provides the convex portion (81) with a line contact having a friction coefficient as small as possible. At this time, a corner (933) and the projection (81) line tangent <br/> occurring between the catalyst will provide a frictional force less than the abnormality external force applied to the nut clutch (9).

FIG. 4 (a) shows a state in which the clutch plate (8) and the nut clutch (9) are mutually coupled to provide a braking force to the nut clutch (9).

At this time, the seating load is removed from the seat plate (20) and the cylinder pipe (2) is lifted by the current restoring force of the spring (5) to be fixedly installed in the cylinder pipe (2). When the plate (8) and the nut clutch (9) are coupled to each other and a rotational force is applied to the seat plate (20), the rotational force is transmitted through the cylinder pipe (2) and the clutch plate (8). ) Is performed to adjust the height of the chair.

At this time, a rotational force slightly larger than the frictional force generated between the corner (933) in the concave groove (93) and the convex portion (81) of the latch plate (8) is applied to the clutch plate (8). When transmitted, the nut clutch (9) rides on the curved surface of the convex portion (81) of the clutch plate (8) and slides up. Such a sliding phenomenon pushes the nut clutch (9) upward as shown in FIG. 4 (a) by the height provided by the convex portion (81) of the clutch, and the clutch function is automatically released. The clutch release operation that occurs in this way is impossible for the adjustment device,
That is, the nut clutch (9) is attached to the screw shaft (1
The purpose is to prevent the user from inadvertently turning the chair unnecessarily at the upper and lower ends of 1) to cause the tightening phenomenon in the clutch structure, and the inclined portion (932) provided in the groove (93) is About 45 degrees is preferred.

5 and 6, the screw shaft (11) is shown.
The coupling structure of the screw shaft (1
1) is a screw shaft (11) on the bottom of the support pipe (1)
It is fixedly installed so that it cannot rotate in the axial length direction and the direction intersecting the axial direction.

That is, a flange type bush (30) which is separately manufactured at the terminal end of the screw shaft (11) and forcibly press-fitted and fixed, and a fixing which is perforated in a polygonal shape on the bottom surface (120) of the support pipe (1). Coupling force is provided by the hole (121) and another clip (40).

To explain further, the flange type bush (3
0) is integrally provided with a flange (31) having a diameter slightly wider than the diameter of the fixing hole (121) of the strut pipe (1) in the horizontal direction intersecting the length direction of the bush body from the lower outer peripheral wall of the bush, and Immediately below the flange (31) of the fixing hole (121) is integrally formed with a retaining portion (32) which is freely insertable and detachable and is coupled in a mating manner to prevent rotation of the screw shaft (11). Is equipped with. At this time, the flange (31) is attached to the bottom surface (12) of the support pipe (1).
0) and the screw shaft (11) is mounted on the bottom surface (12).
0) It will prevent falling below. Further, the screw shaft (1 which is exposed through the flange type bush (30)
1) A hook groove (111) is provided on the outer peripheral wall of the terminal end in a direction intersecting the length direction of the screw shaft (11), and a clip (40) is detachably fitted to the hook groove (111). Combined, the screw shaft (11) is integrally fixed to the bottom surface (120) of the strut pipe (1). At this time, the hooking groove (111) is provided at a distance from the lower end of the flange type bush (30). That is, it is provided at the same position as the combined length of the bottom surface (120) of the strut pipe (1) and the washer (200) from the flange (31), and the clip (40) is provided in the hanging groove (111). When is engaged, the screw shaft (11) is fixedly maintained so as not to rotate in the vertical direction from the bottom surface of the support pipe (1).

The clip (40) is formed by bending a small-width plate body into a U-shape so as to face the screw shaft (11) in parallel with the first support surface (41) and the second support surface (4).
2) is integrated. And this first and second
A first through hole (411) and a second through hole (42) each having an inner diameter large enough to allow the end of the screw shaft (11) to be freely inserted and removed at the center of each of the support surfaces (41) and (42).
1) is provided. At this time, the first supporting surface (41) provides a corresponding holding force to the bottom surface (120) of the strut pipe (1). The end surface of the first supporting surface is a curved surface, and the first through hole (411) provided at the center of the first supporting surface (41) has a hook groove (11) provided on the screw shaft (11). To accommodate the load.

Then, the second supporting surface (42) is cut at the center thereof, and three surfaces in the clip length direction are cut from the supporting surface,
When one side is integrally connected to the support surface and the clip (40) is fitted to the screw shaft, the pressure is applied to the end area portion of the screw shaft to prevent the clip (40) from coming off the screw shaft (11). It comprises a piece (422).
Such a clip (40) is manufactured by a suitable pressing process using a metal plate material having excellent elastic strength.

Next, the lift operation of the chair will be described with reference to FIGS.

[0049] Figure 2 (A) is a sectional view of a state in which no sitting person in the chair, without being acts seated load when the occupant is not sitting, the cylinder pipe (2) the second scan pre < The cylinder pipe (2) is raised by the expansion force of the ring (5).
The clutch plate (8) and the nut clutch (9) provided at the lower end of the chair are coupled to perform the target chair height adjustment work.

That is, if the clutch plate (8) and the nut clutch (9) are connected to each other and the seat plate (20) of the chair is rotated left and right as in the state of FIG. The rotational force applied to (20) is transmitted to the clutch plate (8) through the cylinder pipe (2), and the rotational force transmitted to the clutch plate (8) is meshed with the clutch plate (8). The rotating nut clutch (9) will rotate in that direction. At this time, nut clutch (9)
Ride on the screw shaft (11) assembled according to the screw tightening method, and perform the intended height adjustment work by descending and descending.

FIG. 2 (a) shows a state in which a seating load is applied on the seat plate (20). When the seating load is applied on the seat plate (20), the cylinder pipe (2) is lowered downward.
The clutch plate (8) provided at the lower end of the cylinder pipe (2) is separated from the nut clutch (9) and the lowering is transmitted to the upper surface of the nut clutch (9) through the cylinder pipe (2). The seating load is transmitted to the spring (5), the sleeve (6), and the thrust bearing (7), and the seating load is placed on the nut clutch (9), and the seating position of the chair is determined by the nut clutch (9). . At this time, the spring (5) is contracted by the seating load in the stretched state, and functions as a space maintaining member between the washer (4) and the sleeve (6).
The seating load is transferred directly onto the nut clutch (9).

In such a state, that is, when a seating load is applied to the seat plate, the clutch work is not performed even if the cylinder pipe rotates, the cylinder pipe is idled only, and when the seated person rotates. High and low adjustment actions are not performed. At this time, the seating load is intensively transmitted to the nut clutch (9) through the thrust bearing (7), and a frictional force acts between the thrust bearing (7) and the nut clutch (9) due to the seating load. hand,
Such a frictional force transmits the rotational force applied to the cylinder pipe to the nut clutch (9), and the nut clutch (9).
However, the biting force of the O-ring (91) housed in the vacant chamber (92) of the nut clutch (9) acts to be slightly larger than the contact force, and the nut clutch (9) is moved. ) Does not move easily due to seating load or external force, picks up the adjustment position and keeps the high and low adjustment positions stable and strongly fixed.

[0053] Further, the screw shaft with a simple structure for accommodating the O-ring inside the nut clutch (9) by applying a braking force to (11), rubber ring previously nut gold tool surface and the washer like many mechanical The number of parts, the manufacturing process, and the labor can be reduced as compared with the required elements.

By the clutch function of the clutch plate (8) and the nut clutch (9), the power transmission for adjusting the height is interrupted and the vertical portion is formed in the concave groove (93) of the nut clutch (9). (931) and inclined part (932)
And a corner portion (933) is provided at a point where they meet each other, and a load more than a predetermined amount, that is, when the height of the chair is adjusted,
When <br/> abnormal external force seat plate in a state of reaching the top end (20) turning the nut clutch (9) is a screw shaft user inadvertently (11) of action, the nut clutch (9) Groove (9
3) Vertical and inclined parts (931) provided in
(932) causes the convex portion (81) of the clutch plate (8) to slip, so that the nut clutch (9) and the clutch plate (8) are automatically separated. ) Of the nut clutch (9) is completely prevented, and not only the problem of disengaging the nut clutch (9) is eliminated, but also when it is disengaged, the mechanical element is broken or damaged due to the transmission of impact to the joint of the support body. Completely prevent the fear to improve the productability and extend the life.

On the other hand, in the screw shaft (11), the clip (40) is fitted upward from the lower part to the terminal end portion of the screw shaft (11) penetrating the bottom surface (120) of the column pipe (1) as shown in FIG. After that, if the first supporting surface (41) of the clip (40) is aligned with the engaging groove (111) provided in the screw shaft (11), the clip (40) is inserted leftward in that state to insert the first supporting surface (41). 41) second
The inner peripheral surface of the through hole (411) is fitted into the hooking groove (111) of the screw shaft (11) on one side to generate a hooking force.

At this time, due to the curved surface of the first support surface (41), a holding force corresponding to the opposite direction acts on the bottom surface of the support pipe. Such a force of the first supporting surface (41) generates a descending force that pushes the screw shaft (11) below the bottom surface, and on the contrary, the flange (31) provided on the flange type bush (30) is a support pipe. The screw shaft (11) is fixed on the bottom surface by a holding force applied to the screw shaft (11) that is applied on the bottom surface of the screw shaft (11) and is about to fall. And this screw shaft (11)
Of the flange type bush (30), the polygonal retaining part (32) integrally provided on the lower part of the flange (31) is provided on the bottom surface (120) of the strut pipe (1). The screw shaft (11) is fitted to the strut pipe in a fitting manner, and is prevented from being rotated in a direction intersecting the axial length direction, so that the screw shaft (11) is simply fitted and fixed in the strut pipe. .

As a result, when the screw shaft (11) or the strut pipe is damaged, only the damaged parts can be partially replaced and repaired, which is uneconomical to replace the entire strut pipe in the related art. It is easy to assemble and has excellent productivity. In addition, there is an advantage that both the conventional telescopic type and the screw type columns can be used in combination.

FIG. 7 shows another embodiment of the present invention.

In this embodiment, the same parts are indicated by adding "300" to the same symbols. The difference between the two embodiments is that the cylinder pipe (30
The insertion portion (321) provided at the upper end portion of 2) is not tapered as in the above embodiment, but the cylinder pipe (3)
The outer diameter of 02) is extended as it is to form a straight pipe shape, and the first spring (351) is provided therein, except that the cylinder pipe (302) is provided with an upper end portion. The seat plate (20) is fitted and coupled to the insertion portion (321) and mounted.

Although the embodiment of the present invention has been described above, the present invention is not limited to this, and modifications can be made within the scope described in the claims for utility model registration.

[0061]

As described above, according to the present invention, the column is provided between the seat plate provided with the back portion and the leg, and the column is
A clutch unit having a nut clutch and a clutch plate is provided, a vertical portion and an inclined portion are provided in a concave groove of the nut clutch, and a corner portion is provided at a combined point. Since the nut clutch and the clutch plate are automatically separated by giving a slip phenomenon to the, it is possible to provide a height adjustment device for the swivel chair, and
It is possible to prevent the tightening phenomenon and the loosening phenomenon of the nut clutch and to provide a high and low lift which can be assembled by a simple assembling method.

[Brief description of drawings]

FIG. 1 is an overall side view of a swivel chair equipped with a height adjusting device of the present invention.

FIG. 2 is a cross-sectional view showing the internal structure of a height adjusting device for a swivel chair according to the present invention, (a) showing an example of the swivel chair in a non-seated state, and (a) when the swivel chair is seated. It is an illustration figure of a state.

FIG. 3 is a bottom exploded perspective view of a nut clutch applied to the height adjusting device for a swivel chair according to the present invention.

FIG. 4 is an explanatory view in which a clutch plate of a clutch unit, which is a main configuration of the present invention, and a meshing portion of a nut clutch are developed.

FIG. 5 is an exploded perspective view of a screw shaft and a support pipe applied to the adjusting device of the present invention.

FIG. 6 is an enlarged cross-sectional view of an essential part showing a connecting structure of a screw shaft and a strut pipe according to the present invention.

FIG. 7 is a sectional view showing another embodiment of the present invention.

[Simple explanation of symbols]

 1 Strut pipe 1a Bush 2 Cylinder pipe 4 Washer 5 Spring 6 Sleeve 7 Thrust bearing 8 Clutch plate 9 Nut clutch 10 Leg 11 Screw shaft 20 Seat plate 30 Flange type bush 40 Clip 81 Clutch convex part 91 O-ring 93 Clutch concave groove 111 hanging Groove 120 bottom

Claims (4)

[Scope of utility model registration request] 1. A leg (10) and seat plate (20) and strut pipe (1) and the cylinder pipe (2) in stretched-shrinkable to fit so I if combined configurations of struts between is interposed , the cylinder pipe (2) of the strut, bushing than the upper (3), washer (4), the second spring (5), the sleeve (6) and thrust bearing (7) on each
The screw shaft (11) is provided so as to be movable downward , and penetrates through the central portions of these and extends between the support pipe (1) and the cylinder pipe (2).
And the lower end of the screw shaft (11) is
Fixed to the lower end of the screw (1), the washer (4) rotates on the upper end of the screw shaft (11)
Operably coupled, the bush (3) on the washer (4)
A sleeve (6) as well as a thrust bearing (7)
Combined with the screw shaft (11) so that it can move up and down.
The second spring (5) and the washer (4) and the three
The thrust bearing (7) below the thrust bearing (7).
-The nut clutch (9) and clutch plate on the shaft (11)
(8) is provided, and the nut clutch (9) is screwed onto the screw shaft (11).
The clutch plate (8) below the nut clutch (9).
Is fixed to the lower end of the cylinder pipe (2) and a seating load is applied or not applied to the seat plate, whereby the nut clutch (9) of the clutch unit is applied.
In a height adjusting device for the height of a swivel chair, in which a concave groove (93) provided and a convex portion (81) provided on the clutch plate (8) are coupled and released, a nut clutch (9) of the clutch unit is provided. vertical section of the groove (93) and (931), the convex portion of the clutch plate (8) (81), the abnormal external force application is to provide a sliding during working to release the clutch unit, the clutch
As the plate (8) is idling, Na Ttokuratchi (9)
A height adjusting device for the height of a swivel chair, characterized in that the concave groove (93) is provided with an inclined portion (932). 2. A chamber (92) for providing a space of a limited size is formed on an inner peripheral wall of the nut clutch (9) of the clutch unit, and the chamber (92) has an appropriate cushioning property. The O-ring (9) is inserted tightly and provides a biting force to the teeth of the screw shaft (11) with an appropriate pressure to prevent the nut clutch (9) from loosening due to an external force.
The apparatus of claim 1 including comprising 1). 3. The screw shaft (1) mounted on the bottom surface of the support pipe (1) at the end of the screw shaft (11).
1) A flange (31) that provides a force to withstand the descent, and a polygonal fixing hole (121) provided at the bottom of the support pipe (1) at the bottom of this flange, and the fixing hole (121) that has the same shape. A retaining portion (32) that is freely insertably / removably fitted and coupled to support rotation of the screw shaft (11).
And a clip (40) for providing a holding force that opposes the flange, is engageably coupled with the clip (40).
11) The device according to claim 1, comprising: 4. The device according to claim 1, characterized in that a first spring (51) having a clearance adjusting function is provided between the upper portion of the clutch unit and the cylinder pipe (2).