JPH0451630Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] The invention relates to a device that can fix the seat of a chair in a horizontal position, which can be tilted back and forth comfortably by the repulsive force of a spring. .

[Conventional technology]

The device for fixing the seat of a chair, which can be tilted up and down by the repulsive force of a spring, in a horizontal position is the side surface of a support arm that faces forward and upward, provided at the top end of the leg lever, and the front end of the support arm. By drilling through holes in the sides of the mounting plate of the rear facing seat plate which is pivoted to the seat plate, and passing the fixing rod through both through holes,
Generally, the seat plate is fixed.

However, with this device, when fixing the seat plate, it is necessary to match both through holes accurately, so it must be manufactured with high precision, which is troublesome, and it is difficult to smoothly insert and remove the fixing rod. In this case, it is necessary to make one of the through holes slightly larger in diameter than the fixing rod, and it is unavoidable that some wobbling will occur when the seat plate is fixed.

A device that addresses this problem is disclosed in Japanese Utility Model Publication No. 59-5397.

This device has an inverted L-shaped hole in the support arm and an oblong hole in the mounting plate in place of the above-mentioned through hole.
By positioning the fixing rods inserted through both holes at the front ends of the horizontal parts of the reverse L-shaped holes, the seat plate is fixed, and by positioning the fixing rods at the vertical parts of the reverse L-shaped holes, The seat plate can be tilted up and down.

[Problem that the invention attempts to solve]

In the device described in the above publication, if an excessive downward load is applied to the seat plate, there is a risk that the fixing rod, the horizontally long hole, or the reverse L-shaped hole will be damaged.

[Means for solving problems]

In this invention, the mounting plate of the seat plate, which faces rearward above the support arm, is attached to the front end of the support arm, which is provided at the upper end of the leg lever and faces forward and upward, so that it can be tilted up and down with a pivot that faces left and right. In the chair, the mounting plate is biased upward by an appropriate spring, and a movable member is attached to the front end of the support arm, above the pivot shaft, so that the mounting plate can be slid back and forth by operating the handle. A lock is provided, and a fixed lock piece is provided on the lower front part of the mounting plate that can come into contact with the upper surface of the movable lock, and when the movable lock is moved forward, the rear edge of the movable lock passes through the center of the pivot. The positions of the movable lock and the fixed lock piece are adjusted so that when the movable lock is moved back, the front edge of the movable lock is on or behind the vertical plane. By determining the dimensions, the above-mentioned problems are solved.

[Effect]

When the movable lock is advanced so that its rear edge is on or in front of a vertical plane passing through the center of the pivot, the seat plate can be tilted downward.

Furthermore, when the movable lock is moved back and its front edge is on or behind the vertical plane, the seat plate can be tilted upward.

When the movable lock is in the middle position as described above, the seat plate is fixed, and at this time, the horizontal movable locks on the front and rear overlap with the fixed lock pieces on the seat plate over a wide area, so that the seat plate does not move in a large downward direction. The fixation device will not be damaged even when subjected to loads.

〔Example〕

1 to 3 show an embodiment of the present invention, in which a bent part of a support arm 2 having a U-shape facing forward (to the left in the figure) is fixed to the upper end of a leg rod 1 of a chair. A support plate 3 that is substantially horizontal and faces rearward is fixed to the inner front end of the support arm 2, and above the support plate 3, a connecting cylinder 4 that faces left and right is fixed to the inner side of the support arm 2. ing.

A seat (not shown) mounting plate 5 facing rearward is fixed to the outer end of the pivot shaft 6 inserted into the connecting tube 4 .

A reinforcing rod 7 facing in the left-right direction is fixed to the rear end of the lower surface of the mounting plate 5.

At the front of the support plate 3, there is a leaf spring 8 facing rearward.
The retainer plate 9 is fixed with the screw 10, and the leaf spring 8
The rear end engages with the lower surface of the reinforcing rod 7 and urges it upward.

The leaf spring 8 is made by stacking a plurality of spring pieces 8a, which become shorter toward the bottom, with their front ends aligned.

A support rod 11 is provided between the support plate 3 and the leaf spring 8. The support rod 11 faces in the left-right direction and has both ends slidable back and forth in forward-facing slots cut into the support arm 2. By changing the position of the support rod 11 back and forth, the urging force of the leaf spring 8 can be adjusted.

Between the front end of the support arm 2 and the front end of the mounting plate 5, a pair of cylindrical stoppers 12 are fitted to both ends of the pivot shaft 6, respectively. The stopper 12 is fixed to the support arm 2.

The facing surface of each stopper 12 is notched in a circular shape, so that the protrusions 12a engage with each other, and both protrusions 1
A gap 13 parallel to the axis is formed between the front ends of 2a (the rear gap is not shown).

Between the inner front ends of the support arm 2, the connecting cylinder 4
A fixing plate 14 facing rearward is fixed to the upper surface of. A movable lock 15 is provided on the upper surface of the fixed plate 14.
is mounted so that it can be moved back and forth.

The movable lock 15 includes a front lock 15a and a rear lock 15b formed through a horizontal engagement groove 16 cut into its upper surface.

A fixing plate 14 is inserted into the engagement groove 16 with a vertical pin 17 facing in the inner and outer directions and slightly outward from the inner end.
The inner end of a handle 18 pivotally connected to the handle 18 is engaged, and the movable lock 15 can be slid back and forth by operating the handle 18.

1 and 3 show the state in which the mounting plate 5 is fixed and held horizontally, the upper surface of the fixed plate 14 and the movable lock 15 are horizontal, and the vertical plane H passing through the center of the pivot 6 is It is located between the leading and trailing edges of the front lock 15a.

A pair of front and rear fixed lock pieces 19a and 19b, which face in the left-right direction and are parallel to each other, are fixed to the opposing portion of the lower front portion of the mounting plate 5 to the movable lock 15. Each fixed lock piece 19a, 19b
are the front lock 15a and the rear lock 1, respectively.
The mounting plate 5 is superimposed on the upper surface of the mounting plate 5b and is held at two points, front and back, so that the mounting plate 5 is fixedly held without tilting.

As shown in FIG. 4A, when the movable lock 15 is moved forward by operating the handle 18 from the above-mentioned state, the front lock 1 is moved forward near its front limit.
The rear edge of the rear lock 5a substantially coincides with the vertical plane H, and the rear edge of the rear lock 15b comes off slightly in front of the front edge of the rear fixed lock piece 19b.

Therefore, as shown in FIG. 4B, the rear fixing lock piece 19b can be lowered to the rear side of the rear lock 15b, and the mounting plate 5 is moved against the leaf spring 8 until the gap 13 is eliminated. , can be tilted downward.

In the state shown in FIG. 4A, the front fixing lock piece 19a overlaps the front lock 15a over a fairly long range in the front-rear direction, so the mounting plate 5 cannot be tilted upward.

As shown in FIG. 5A, when the movable lock 15 in the state shown in FIG.
The front edge of the front lock 1 coincides with the vertical plane H and
The rear edge of the rear lock 5a and both front and rear edges of the rear lock 15b are
All come behind the vertical plane H.

Therefore, as shown in FIG. 5B, the mounting plate 5
can be tilted upward until the gap (not shown) behind both stoppers 12 is eliminated.
In the state shown in FIG. 5A, the rear fixing lock piece 19b overlaps the rear lock 15b over a fairly long range in the front-rear direction, so the mounting plate 5 cannot be tilted downward.

By setting the position of the vertical plane H to the rear of the state shown in the figure and slightly changing the dimensions and positions of the movable lock 15, front lock 19a, and rear lock 19b, it is possible to tilt the mounting plate 5 downward and upward. The manner in which the mounting plate 5 is released from the fixing can be reversed to that described above.

Although not shown, the fixed locks 19a, 1
With 9b as one continuous piece, the movable lock 15 is
By moving the mounting plate 5 until its front edge or rear edge reaches the vertical plane H, the mounting plate 5 can be tilted upward or downward.

[Effect of idea]

According to the present invention, it is easy to fix and release the mounting plate, that is, the seat plate, and when the plate is fixed, the horizontal movable lock and the fixed lock piece on the seat plate overlap over a wide area. Even if the seat plate receives a large downward load, the fixing device will not be damaged and the seat plate will be securely fixed.

[Brief explanation of drawings]

Fig. 1 is a vertical sectional side view of the main part of a chair to which the present invention is applied when the seat plate is fixed, Fig. 2 is a sectional view taken along line A-A in Fig. 1, and Fig. 3 is B in Fig. 2. Figure 4A, which is a view taken along line -B, shows the state in which the seat plate mounting plate of the chair to which the present invention is applied can be tilted downward, and Figure 2C
4B is a diagram showing a state in which the seat mounting plate of the chair is tilted downward from the state shown in FIG. 4A, and FIG. 4A and FIG. 5B are views showing a state in which the seat mounting plate is tilted upward from the state shown in FIG. 5A. 1... Leg rod, 2... Support arm, 3... Support plate, 4... Connection tube, 5... Mounting plate, 6... Pivot,
7... Reinforcement rod, 8a... Leaf spring piece, 8... Leaf spring, 9... Holding plate, 10... Screw, 11... Support frame, 12... Stopper, 12a... Projection, 13
...Gap, 14... Fixed plate, 15... Movable lock, 15a... Front lock, 15b... Rear lock, 16... Engagement groove, 17... Vertical pin, 18...
...handle, 19a, 19b...fixing lock piece,
H...Vertical surface.

Claims (1)

[Scope of utility model registration request] A mounting plate of a seat plate facing rearward above the support arm is pivotally mounted to the front end of a support arm provided at the upper end of the leg rod and facing forward and upward, with a pivot pointing in the left-right direction so as to be tiltable up and down, This mounting plate
In a chair which is biased upward by a suitable spring, a movable lock is provided at the front end of the support arm above the pivot shaft and can be slid back and forth by operating the handle, and the mounting plate is A fixed lock piece that can come into contact with the upper surface of the movable lock is provided at the front of the lower surface, and when the movable lock is moved forward, the rear edge of the movable lock moves on or forward of a vertical plane passing through the center of the pivot shaft. Next, when the movable lock is moved back, the front edge of the movable lock will be on the vertical plane or behind it.
A fixing device for a tilting seat plate of a chair, characterized in that the positions and front-rear dimensions of a movable lock and a fixed lock piece are determined.