JPH08205954A - Backrest angle adjusting device - Google Patents

Abstract

PURPOSE: To erect a backrest of a seat in an erecting direction even from an any angle position only by applying a force in a direction to erect the backrest. CONSTITUTION: In this backrest angle adjusting device A of cylinder type which adjusts the angle of the backrest by applying an opening/closing operation to an opening/closing valve 8 disposed in a piston 3 from the outside, an oil passage for bypass is formed in parallel with an oil path 6 passing the opening/ closing valve 8. A part of the oil passage is constituted of an annular groove 19 piercing through the outer periphery of the piston 3, and also, an annular seal band 22 consisting of an elastic material is fitted in the annular groove 19, and the operation in the erecting direction of the backrest is permitted without relating to the opening/closing operation of the opening/closing valve 8 setting the seal band 22 as a relief valve.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cylinder type backrest angle adjusting device for reclining seats used in trains, theaters, planetariums and the like.

[0002]

2. Description of the Related Art As shown in FIG. 4, a cylinder type backrest angle adjusting device which has been generally used in the past inserts a piston 3 bearing a piston rod 2 into a cylinder 1 slidably. The two working chambers R on the rod side and the head side where the inside of the cylinder 1 is filled with hydraulic oil at 3
It is divided into H.

The inside of the working chamber H located on the head side is further divided into two chambers by the free piston 4, thereby defining a gas chamber G in the portion opposite to the piston 3.

The piston 3 is provided with an oil passage 6 having an orifice 5 for communicating the two working chambers R and H on the rod side and the head side, and the outlet portion of this oil passage 6 on the working chamber H side. An opening / closing valve 8 is provided by slidably inserting the tip of the guide rod 7 into the piston 3.

This on-off valve 8 has a synergistic action between the pressure receiving area difference between both surfaces due to the presence of the guide rod 7 and the hydraulic oil pressure in the working chambers R and H based on the gas pressure in the gas chamber G.
It is pushed to the side to close the oil passage 6 in a normal state.

In order to open / close the open / close valve 8 from the outside, an operation rod 9 is slidably inserted through the axial center portion of the piston rod 2, and the external protruding end of the operation rod 9 is operated. By pushing with the lever 10, the on-off valve 8 can be pushed open by overcoming the closing force due to the internal hydraulic pressure.

Inside the rod-side working chamber R, a stopper 12 is provided whose position is regulated by roll crimping 11 provided on the cylinder 1, and the most extended position of the piston 3 is limited by the stopper 12. Ensures a minimum fitting length between the cylinder 1 and the piston 3.

As shown in FIG. 5, the seat backrest angle adjusting device constructed as described above is attached to the base end of the cylinder 1 and the external projecting end of the piston rod 2, respectively. Is used to interpose between the seat S and the backrest B.

Thus, when the backrest B is tilted down, the operation lever 10 of the backrest angle adjusting device is operated while pushing the backrest B with the back while seated on the seat S.

As a result, the opening / closing valve 8 in the piston 3 is pushed through the operating rod 9 to overcome the closing force due to the hydraulic oil pressure, and is opened, whereby the rod-side and head-side operating chambers R and H are opened.
Communicate with each other through the oil passage 6 of the piston 3.

Therefore, the cylinder 1 of the backrest angle adjusting device, which is pushed in the contraction direction through the backrest B, pushes the hydraulic oil in the working chamber H into the working chamber R from the oil passage 6 under the regulation of the orifice 5. While moving in the contraction direction, the backrest B falls down at a predetermined speed while contracting the backrest angle adjusting device.

At the same time, the free piston 4 is slower than the contraction speed of the cylinder 1 according to the difference in sectional area between the piston rod 2 and the piston 3 in the gas chamber G.
It operates in the contracting direction while compressing the gas inside, thus,
Backrest B falls backwards.

If the operation lever 10 is released when the backrest B is tilted to a desired angle, the opening / closing valve 8 automatically closes the oil passage 6 of the piston 3 due to the pressure-receiving area difference between the two surfaces. The leaning angle adjusting device returns to the original locked state, and the backrest B is held at the desired angle and stopped.

On the other hand, when raising the backrest B toward the front, the operating lever 10 is operated while the back is separated from the backrest B, and the open / close valve 8 is passed through the operating rod 9.
I'll open it.

Then, this time, the cylinder 1 causes the synergistic action of the difference in sectional area between the working chambers R and H due to the existence of the piston rod 2 and the hydraulic oil pressure in the working chambers R and H based on the gas pressure in the gas chamber G. Then, the hydraulic oil in the working chamber R is pushed in the working chamber H from the oil passage 6 under the restriction of the orifice 5 and operates in the extending direction.

In addition to the above, the free piston 4
However, for the extension speed of the cylinder 1, the piston rod 2
And the piston 3 is pushed by the gas pressure in the gas chamber G at a slower speed according to the difference in cross-sectional area of the piston 3 and moves toward the extension side.

As a result, the backrest angle adjusting device is pushed by the gas pressure in the gas chamber G and automatically operates in the extension direction to raise the backrest B forward.

Moreover, even in this case, if the backrest B is raised to a desired angle and the operation lever 10 is released and the opening / closing valve 8 is closed, the desired angle is maintained. Leaning B will stop.

[0019]

However, in the reclining seats used in trains, theaters, planetariums, etc., the angles Y, Z (Fig. It is necessary to return the backrest B adjusted to the reference position) to the original standing position X and arrange it.

In this case, in the above-mentioned backrest angle adjusting device, the backrest B is operated by operating the operating lever 10 one by one.
Must be raised to the standing position X.

As a result, it takes a lot of time and effort to arrange the backrest B, and in particular, the backrest B is arranged in addition to the cleaning within a limited time, such as when the customer is changing or replacing. There is a problem that performing work is also a very difficult work.

Therefore, an object of the present invention is to provide a cylinder type cylinder capable of returning the backrest from any angular position to the original standing position by simply applying a force in the standing direction to the backrest. It is to provide a backrest angle adjusting device.

[0023]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a cylinder type backrest angle adjusting device for adjusting the backrest angle by opening and closing an opening / closing valve provided on the piston from the outside. This is achieved by providing a bypass oil passage in parallel with the oil passage passing through the opening / closing valve, and arranging a relief valve that opens in a direction that allows the backrest to stand upright in the oil passage.

Further, preferably, a part of the oil passage is formed by an annular groove formed in the outer peripheral surface of the piston, and an annular seal band made of an elastic material is fitted in the annular groove to support the backrest. This can be achieved even more effectively by using a relief valve that opens in a direction that allows the rise of the valve.

[0025]

In other words, in this type of cylinder type backrest angle adjusting device, when an external force in the standing direction is applied to the tilted backrest, the backrest angle adjusting device extends through the backrest. Is applied, and in proportion to the magnitude of this force, the hydraulic oil pressure in the working chamber on the rod side defined by the piston in the backrest angle adjusting device rises.

Therefore, when the tilted backrest is returned to the upright direction, the working oil pressure applied to the working chamber on the rod side is relieved in the oil passage arranged in parallel with the oil passage passing through the on-off valve. An external force in the standing direction is applied to the backrest so as to exceed the cracking pressure of the valve.

As a result, even if the open / close valve is closed, the relief valve in the oil passage opens to allow the working oil in the rod-side working chamber to flow from the oil passage into the head-side working chamber. Along with this, the backrest angle adjusting device can move in the extension direction to return the backrest to the original standing position.

[0028]

BEST MODE FOR CARRYING OUT THE INVENTION Preferred embodiments of the present invention will be described below with reference to the drawings. With respect to other configurations and usages except the piston portion, the cylinder type backrest angle adjusting device of the conventional example described above is used. Therefore, only different parts will be shown and described here.

In FIG. 1, in the piston 3 in the seat backrest angle adjusting device A of the cylinder type according to this embodiment, another oil passage 15 bypassing the oil passage 6 passing through the opening / closing valve 8 is provided in the piston 3 in the axial direction. Are provided in parallel with each other.

The opening end of the oil passage 15 to the working chamber H on the head side is covered with a relief valve 16 formed of an annular leaf.

The relief valve 16 includes a retaining ring 17 fixed to the piston 3 by means such as press fitting or screws, and the piston 3.
The inner peripheral part is clamped and fixed by and, by which,
The open end of the oil passage 15 to the working chamber H on the head side is closed by.

Thus, the seat backrest angle adjusting device A according to the present invention constituted by modifying the piston portion of the conventional cylinder type seatback angle adjusting device as described above is as follows. An operation is performed to adjust the angle of the backrest B of the seat S.

That is, the cracking pressure of the relief valve 16 that closes the open end of the oil passage 15 is set to the operating chambers R on the rod side and the head side when the opening / closing valve 8 is closed.
It is set in advance so that the relief valve 16 is not bent and pushed open depending on the pressure difference based on the cross-sectional area difference of H.

As a result, in the backrest angle adjusting device A, not only the opening / closing valve 8 and the relief valve 16 prevent movement in the extension direction, but also the opening / closing valve 8 and the relief valve 16 both close in the compression direction. It is selfish and locked securely.

From this, the operation lever 1 is pushed while pushing the backrest B with the back or with the back away from the backrest B.
By operating 0 and opening the open / close valve 8 through the operating rod 9, the angle of the backrest B is adjusted in the same manner as the conventional backrest angle adjusting device described above.

On the other hand, when an external force in the standing direction is directly applied to the backrest B, a force in the extension direction acts on the backrest angle adjusting device A through the backrest B and is proportional to the magnitude of this force. The hydraulic oil pressure P in the rod-side working chamber R rises.

Here, it is assumed that the flexural rigidity of the relief valve 16 is f, and the opening area of the oil passage 15 at the portion facing the relief valve 16 is a.

Then, the hydraulic oil pressure P in the working chamber R on the rod side is "P>" with respect to the hydraulic oil pressure p in the working chamber H on the head side.
f / a + p ”, pressure working oil in the rod-side working chamber R pushes the relief valve 16 through the oil passage 15 of the piston 3 and opens the working chamber H on the head side.
Begins to flow.

As a result, the backrest angle adjusting device A starts to move in the extension direction by the external force applied to the backrest B, and the backrest B comes up.

From this, the flexural rigidity force f of the relief valve 16 and the relief valve 16 are satisfied so that the above inequality is satisfied based on the magnitude of the external force applied to the backrest B.
By selecting the opening area a of the oil passage 19 of the portion facing to, it is possible to artificially raise the backrest B from any angle position to the standing position X without opening the opening / closing valve 8.

FIG. 2 shows a second embodiment of the present invention. In this embodiment, the bypass oil passage 15 and the relief valve 16 in the first embodiment described above are used.
Is configured as follows.

That is, an annular groove 19 is formed on the outer peripheral surface of the piston 3 side by side with the piston seal 18 near the working chamber H side.

On the one hand, the annular groove 19 passes through the through hole 20 formed in the piston 3 and the rod-side working chamber R in the cylinder 1.
On the other hand, a passage 21 formed by cutting out the outer peripheral surface of the piston 3 also communicates with the working chamber H on the head side.

As a result, the through hole 20, the annular groove 19 and the passage 21 are maintained in parallel with the communicating passage composed of the oil passage 6, the orifice 5 and the opening / closing valve 8 in the first embodiment. An oil passage equivalent to the oil passage 15 for bypass in the example will be formed.

A rubber ring-shaped seal band 22 made of an elastic material such as rubber is installed in the annular groove 19 so as to cover the communicating portion with the through hole 20.
At 2, the communication between the annular groove 19 and the through hole 20 is blocked.

As a result, the seal band 22 opens and closes only with respect to the flow of hydraulic oil from the rod-side working chamber R to the head-side working chamber H through the through hole 20 and controls the flow of the working oil. By doing so, the same function as the relief valve 16 in the first embodiment is fulfilled.

Thus, even in this case, the tightening force f of the seal band 22 and the opening area a of the through hole 20 in the portion facing the seal band 22 are set to the working chambers R and H on the rod side and the head side. It is set in advance so that the seal band 22 is not expanded and opened depending on the pressure difference based on the difference in cross-sectional area.

As a result, in the backrest angle adjusting device A, not only the opening / closing valve 8 and the seal band 22 prevent movement in the extension direction, but also the opening / closing valve 8 and the seal band 22 both close in the compression direction. It is selfish and locked securely.

From this, the operation lever 1 is pushed while pushing the backrest B with the back or with the back away from the backrest B.
The angle of the backrest B is adjusted by operating 0 and opening the open / close valve 8 through the operating rod 9.

On the other hand, when the backrest B is artificially raised without using the operation lever 10, an external force in the standing direction is applied to the backrest B to operate the rod side of the backrest angle adjusting device A. The hydraulic oil pressure P in the chamber R is increased.

Then, the hydraulic oil pressure P in the rod-side working chamber R is "P>" with respect to the working oil pressure p in the head-side working chamber H.
When the pressure rises to “f / a + p”, the pressure working oil in the rod-side working chamber R flows from the through hole 20 through the annular groove 19 and the passage 21 into the working chamber H on the head side while opening the seal band 22.

As a result, the backrest angle adjusting device A operates in the extension direction by the external force applied to the backrest B, and the backrest B comes up.

Therefore, as in the case of the first embodiment, the tightening force f of the seal band 22 is set so as to satisfy the above inequality based on the magnitude of the external force applied to the backrest B.
By selecting the opening area a of the through hole 20 in the portion facing the seal band 22 and the backrest B can be artificially raised from any angle position to the standing position X without opening the opening / closing valve 8. It becomes.

Moreover, the relief valve 16 of the first embodiment can adjust the flexural rigidity force f to some extent by selecting the thickness, material, or flexural support point.

Similarly, the seal band 22 of the second embodiment.
However, not only can the tightening force f be adjusted to some extent by selecting the elastic force or diameter depending on its thickness and material, but in particular, in this case, as shown in FIG. By stacking and energizing the tightening auxiliary member 23 composed of a garter spring and a C-shaped plate winding spring (a garter spring is shown in the figure) on the back side of the
Further, it is possible to make the adjustment range large.

Further, the opening area a of the oil passage 15 or the through hole 20 with respect to the relief valve 16 and the seal band 22.
Also, the hole diameters of the oil passages 15 and the through holes 20 may be changed or the number may be increased or decreased to be arbitrarily adjusted.

Therefore, the flexural rigidity of the relief valve 16 and the tightening force f of the seal band 22 or the opening area a of the oil passage 15 and the through hole 20 in the portion facing the relief valve 16 or the seal band 22 should be adjusted. so,
It becomes possible to appropriately select the magnitude of the external force when artificially raising the backrest B.

Further, in the above embodiments, the oil passage 15, the through hole 20 and the passage 21 are described as simple communicating passages, but by constructing all or part of them as orifices, It goes without saying that the standing speed of the backrest B can be limited within a predetermined range even when an external force larger than a predetermined value is applied.

[0059]

As described above, according to the first aspect of the invention, not only the backrest angle adjusting operation and the tilting direction locking operation can be performed by the on-off valve and the relief valve as in the conventional case, but also By simply applying an external force to the backrest, the relief valve can be erected easily and quickly from any angular position by utilizing the relief valve regardless of the operation of the opening / closing valve.

According to the second aspect of the invention, the above effect can be easily achieved by using the seal band made of the elastic material.

According to the third aspect of the invention, the adjustment range of the tightening force of the seal band can be increased to appropriately set the magnitude of the external force when the backrest is raised.

[Brief description of drawings]

FIG. 1 is a vertical sectional front view of an essential part showing an embodiment of a seat backrest angle adjusting device according to the present invention.

FIG. 2 is likewise a vertical cross-sectional front view of essential parts of another embodiment.

FIG. 3 is a vertical sectional front view of a main part showing a modified example of the above.

FIG. 4 is a vertical cross-sectional front view showing a conventional backrest angle adjusting device for a seat.

FIG. 5 is an explanatory view showing an example of mounting the backrest angle adjusting device on a seat.

[Explanation of symbols]

 A backrest angle adjusting device B backrest S seat 1 cylinder 2 piston rod 3 piston 6 oil passage through the opening / closing valve 8 opening / closing valve 9 operating rod 10 operating lever 15 oil passage for bypass 16 relief valve 19 annular ring that constitutes the oil passage Groove 20 Similarly through hole 21 Similarly passage 22 Seal band which is a relief valve 23 Tightening auxiliary member

Claims (3)

[Claims] 1. A cylinder-type backrest angle adjusting device for adjusting a backrest angle by opening and closing an on-off valve provided on a piston from outside, for bypassing an oil passage passing through the on-off valve in parallel with a piston. The oil passage of
A backrest angle adjusting device characterized in that a relief valve that opens in a direction that allows the backrest to stand is disposed in the oil passage. 2. A cylinder type backrest angle adjusting device for adjusting a backrest angle by opening and closing an on-off valve provided on a piston from the outside, for bypassing a piston in parallel with an oil passage passing through the on-off valve. The oil passage of
A part of this oil passage is formed by an annular groove formed in the outer peripheral surface of the piston, and an annular seal band made of an elastic material is fitted into the annular groove to open in a direction that allows the backrest to stand upright. A backrest angle adjusting device characterized by being a valve. 3. The backrest angle adjusting device according to claim 2, wherein a tightening assist member including a garter spring for adjusting tightening force and a C-shaped plate winding spring is arranged on the outer periphery of the seal band.