JP2504875Y2 - Seat air suspension system for vehicles - Google Patents

Description

[Detailed description of the device]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air suspension device for a vehicle seat, which mainly supports a vehicle seat such as an automobile by using a link mechanism and an air spring.

[0002]

2. Description of the Related Art In general, an air suspension device for a vehicle seat of this type is supported by an air spring by presetting a reference height of a seat cushion in order to secure an appropriate suspension stroke and obtain optimum cushioning performance. I am trying to do it.

An example of this typical vehicle seat air suspension device is shown in Japanese Patent Application Laid-Open No. 54-97924. This is shown in FIG. 7 and FIG.
Will be briefly described. In the figure, reference numeral 1 is a frame-shaped lower frame fixed on the floor of the vehicle, and 2 is a frame-shaped upper frame which is arranged above the lower frame 1 and supports a seat cushion (not shown) of a vehicle seat. Between the upper frame 2 and the lower frame 1, a pair of left and right link mechanisms 3 that support the upper frame 2 in a vertically movable manner are assembled. The left and right link mechanisms 3 each have a pair of link bars 3a and 3b pivotally attached to each other in an X shape via pivot pins 4. An air spring 5 is provided between the lower frame 1 and the upper frame 2 to support the load generated from the seat cushion on the upper frame 2.

The air spring 5 is provided with a valve body 6 for supplying air from an air supply source (not shown) such as a compressor or exhausting air from the inside of the air spring 5. This valve body 6 has an air supply valve 7 and an exhaust valve 8 arranged in parallel in a single casing, and has valve rods 7a and 8a protruding in the same plane side. It is attached and fixed in a substantially frontward state via a bracket 9 protruding in the direction of. The supply / exhaust valves 7 and 8 of the valve body 6 are of a normally closed type, and open when the valve rods 7a and 8a are pushed in, respectively, and when the pushing force is released, they automatically return to the closed state.

One cam 10 is provided as a valve switching mechanism for opening and closing the supply / exhaust valves 7, 8. As shown in FIG. 8, the cam 10 has a substantially fan-shaped plate shape and has raised cam surfaces 10a and 10b on the upper and lower portions on the rear end side opposite to the vertex on the front end side. The cam surface 10 is rotatably fitted and attached to the shaft 11 for pivotally supporting the lower end of the link bar 3a in the state where the front end of the link mechanism 3 is lowered to the front. An arc-shaped elongated hole 10c centering on the shaft 11 is provided in the middle of the cam 10, and a pin 12 protruding from the link bar 3a is slidably fitted into the elongated hole 10c. The cam 10 interlocks with the vertical movement of the link bar 3a with a free running distance x in the elongated hole 10c.

When the seat cushion is lowered from the seat cushion reference height due to the seating of the seated person or the load caused by the traveling vibration of the automobile, the link bar 3a rotates downward together with the pin 12 from the state shown in FIG. After passing the idling distance x in the long hole 10c, the cam 10 is first interlocked and pushed down and rotated. With this, the cam surface 10a on the upper side becomes the valve body 6
The valve rod 7a is pushed in to open the air supply valve 7, compressed air from the air supply source is supplied to the air spring 5, and the pressure of the air spring 5 pushes up the upper frame 2 to raise the seat cushion.

During this ascent, the valve rod 7a remains pressed into the cam surface 10a, the air supply valve 7 is not immediately closed, and the pin 12 and the link bar 3a form the oblong hole 10.
After passing the idling distance x in c, the cam 10 rotates upward, the upper cam surface 10a comes off the valve rod 7a, and the air supply valve 7
Is closed, the air supply to the air spring 5 is stopped, and the seat cushion is returned to and held at the original reference height position.

Contrary to the above, when the seat occupant moves away from the seat or the seat cushion rises from the reference height due to the traveling vibration of the automobile, the cam 10 along with the link bar 3a and the pin 12 from the state shown in FIG. Is rotated in an upward direction by an angle equal to or more than the idling distance x, the lower cam surface 10b pushes the valve rod 8a of the valve body 6 to open the exhaust valve 8 and from inside the air spring 5. Exhaust. This pulls down the upper frame 2 to lower the seat cushion.

During this descent, the valve rod 8a is still pushed into the cam surface 10b, the exhaust valve 8 does not close immediately, and the pin 12 together with the link bar 3a passes the idling distance x in the slot 10c. The cam 10 pivots downwards, the lower cam surface 10b disengages from the valve rod 8a, the exhaust valve 8 closes, the exhaust from the air spring 5 stops, and the seat cushion returns to the standard height position and is held. To be done.

That is, in this vehicle seat air suspension device, when the seat cushion descends or rises from the reference height position due to traveling vibration or the like, the pin 12 and the cam 10 which are interlocked therewith via the link bar 3a of the link mechanism 3 are engaged. The cam 10 has a free running distance x with the long hole 10c of
Is a structure for operating the supply / exhaust valves 7, 8 of the air spring 5. Conversely, even if the seat cushion moves up and down within the range corresponding to the above-mentioned idling distance x from the reference height, the air spring 5 is set as a so-called dead zone in which the seat cushion is not controlled, and the seat cushion has a dead zone above and below. Air spring 5
Is controlled to perform an operation for returning the seat cushion to the reference height.

[0011]

By the way, in the conventional suspension device having the above-mentioned structure, it is possible to adjust the reference height of the seat cushion according to the physique of the seated person. It is not possible to adjust the width of the upper and lower dead zones by adjusting only. For this reason, there is no problem in the case of a seat with a high seat height and a sufficient allowance for the stroke of the suspension.However, for seats with a low seat height due to vehicle space etc. and with insufficient allowance for the stroke of the suspension, the standard height of the seat cushion If the adjustment is set to a low value, the dead band is also reduced by a certain amount, so that the suspension stroke required for the cushioning operation of the seat cannot be secured, and the bottom of the seat cushion is apt to occur.

The present invention has been made in view of the above circumstances, and an object thereof is to adjust the reference height of the seat cushion and at the same time adjust the width of the upper and lower dead zones while having a very simple structure. An object of the present invention is to provide an air suspension device for a vehicle seat, which is capable of sufficiently securing a stroke required for cushioning operation of a seat even if the reference height of the cushion is set low and which is capable of preventing bottoming out and which has excellent cushioning performance.

[0013]

In order to achieve the above object, an air suspension device for a vehicle seat according to the present invention includes a link mechanism, an upper frame, and a lower mechanism that are displaced relative to each other as the seat cushion moves up and down. Of any two members of the frame, one member is provided with a supply / exhaust valve, the other member is provided with a valve switching mechanism facing the supply / exhaust valve, and the valve switching mechanism is provided for the other member. A cam plate pivotally mounted on the cam plate and having a valve switching cam surface on both sides of the tip and an engagement groove whose groove width increases from one end side to the other end side; and the engagement of this cam plate An operation in which the interlocking pin loosely inserted in the groove and the interlocking pin attached to the other member are positioned and held in the engagement groove of the cam plate so that the interlocking pin can be moved and adjusted obliquely with respect to the center line of the engagement groove. Leva And configurations with bets, by moving adjusting the interlocking pin in operation of the operating lever, lowering the reference height of the seat cushion, characterized in that it has at the same time the width of the dead band is set small.

[0014]

In the vehicle seat air suspension device having the above-described structure, when the seat cushion moves up and down, the supply / exhaust valve of one member and the valve switching mechanism of the other member that interlock with the seat cushion move relative to each other. At this time, in the valve switching mechanism, the interlocking pin held by the operation lever interlocking with the other member runs freely in the engagement groove of the cam plate. Then, when the seat cushion exceeds a predetermined vertical dead zone from the set reference height, the interlocking pin pushes one side surface or the other side surface in the engagement groove of the cam plate, whereby the cam plate rotates and the tip end is The valve switching cam selectively opens the supply / exhaust valves to control the internal pressure of the air spring, and tries to restore the seat cushion to the standard height. At this time, the cam plate does not immediately close the intake / exhaust valves, but keeps the valve open state until the interlocking pin reversely migrates in the engagement groove of the cam plate and pushes the opposite side, and the seat cushion When is returned to the reference height, it is pushed by the interlocking pin and the cam plate is returned to rotate to close the supply / exhaust valve. This ensures that the seat cushion will be returned to the reference height position.

When the seat occupant operates the operation lever to change the reference height of the seat cushion in accordance with his / her preference, the interlocking pin causes the interlocking pin in the engagement groove of the cam plate. The movement is adjusted in one or the other direction diagonally with respect to the center line. As a result, the cam plate rotates so that the center line of the engaging groove comes to the moved position of the interlocking pin, and the reference height of the seat cushion is adjusted up and down. At the same time, since the groove width of the engaging groove increases from the one end side to the other end side, the traveling distance of the interlocking pin changes and the width of the upper and lower dead zones of the seat cushion is adjusted to be large or small. become. That is, if the interlocking pin is moved and adjusted by operating the operating lever to lower the reference height of the seat cushion, the width of the dead zone becomes smaller. As a result, even if the seat cushion has a low seat height due to the vehicle space and the stroke of the suspension is not large enough, even if the standard height of the seat cushion is adjusted to a low value, the dead zone width is narrowed by that amount. The stroke required for the operation is not reduced so much, and the occurrence of bottoming due to vibration or the like during traveling of the vehicle is reduced.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS.

In the figure, the same components as those shown in FIGS. 7 and 8 are designated by the same reference numerals to simplify the description.

First, FIG. 1 is a side view of an air suspension device for a vehicle seat. A lower frame 1 fixed on the floor of a vehicle and a vehicle seat placed above the lower frame 1 are arranged in the same manner as in the prior art. An upper frame 2 that supports a seat cushion (not shown), a pair of left and right link mechanisms 3 that supports the upper frame 2 so that the upper frame 2 can move up and down with respect to the lower frame 1, and an air spring that supports a load generated in the upper frame 2. 5 and the air spring 5 to supply air from an air supply source or to exhaust air from the inside of the air spring 5.
When the valve body 6 having the air distribution valves 7 and 8 and the seat cushion move up and down from the reference height Z and exceed predetermined dead zones A and B, the supply / exhaust valves 7 and 8 are selectively opened. And a valve switching mechanism 20 for returning the seat cushion to the reference height by controlling the internal pressure of the air spring 5.
In this air suspension device, a shock absorber 21 is provided between the lower frame 1 and the upper frame 2.

The valve body 6 provided with the supply / exhaust valves 7 and 8 is
One of the two members that are displaced relative to each other with the vertical movement of the seat cushion, that is, the X of the link mechanism 3.
Of the link bars 3a and 3b pivotally attached in a letter shape, they are attached and fixed to the middle part of one of the link bars 3b arranged at the forward rising inclination, and the valve bars 7a and 8a are respectively attached to the link bars 3b.
In a vertically symmetrical position with the center line D sandwiched therebetween, each of them is in a state of projecting obliquely upward in parallel with the center line D.

The valve switching mechanism 20 is mounted on the upper frame 2 which moves relative to the link bar 3b.
The valve switching mechanism 20 controls the internal pressure of the air spring 5 by the supply / exhaust valves 7 and 8 to control the seat cushion reference height Z.
And the dead zones A and B above and below the reference height of the seat cushion are secured, and the reference height Z and the widths of the upper and lower dead zones A and B can be adjusted. It is said that.

That is, as shown in FIGS. 1 to 3, the valve switching mechanism 20 includes a cam plate 22 for switching the supply / exhaust valves 7 and 8 and an interlocking mechanism for interlocking the cam plate 22 and the upper frame 2. Pin 23 and this interlocking pin 2
3 is a configuration including an operation lever 24 that positions and holds the movable body 3 so that the movable body 3 can be adjusted.

The cam plate 22 is a substantially lateral T-shaped plate, and its base end portion (front end portion) is rotatably pivoted to the inner frame of the upper frame 2 by a pivoting pin 25 with the link bar 3b. The valve rods 7a and 8a of the supply / exhaust valves 7 and 8 are attached to the upper and lower parts of the front end side (rear end side) surface.
The valve switching cam surfaces 22a and 22b for pressing the valve to open the valve are formed. Further, the cam plate 22 has a protruding portion 22c above the base end portion thereof, and an engaging groove 22d is formed in the protruding portion 22c. The engagement groove 22d has a groove width that increases from one end side to the other end side. That is, the engagement groove 22d is a V-shaped groove that gradually expands as it goes away from the pivot pin 25 which is the center of rotation of the cam plate 22. The interlocking pin 23 is supported by the operation lever 24 in the V-shaped engagement groove 22d and is loosely inserted in a state orthogonal to the operation lever 24.

The operating lever 24 is a rotating lever 26.
And a lock lever 27 that completes this rotation in multiple stages.

The rotating lever 26 is in the shape of a horizontally long strip plate, and the rear end of the rotating lever 26 is fitted to a mounting pin 28 projecting from the outer surface of the upper frame 2 so that it can be rotated in the vertical direction. ing. The mounting pin 28 is provided at a position eccentric to the rear from the pivot pin 25 which is the center of rotation of the cam plate 22. The interlocking pin 23 is fixed inwardly to an upper protruding portion 26a near the rear end of the rotating lever 26, and the interlocking pin 23 passes above the upper frame 2 and engages with the engaging groove 2 of the cam plate 22.
It is loosely inserted in 2d.

The lock lever 27 is in the shape of a horizontally elongated strip plate which is bent so that the front end thereof can be easily pushed by a finger. The lock lever 27 is slidably fitted in a guide pin 29 projecting from the front end portion on the outer side surface of the rotating lever 26 so as to be movable back and forth, and at the rear end portion inside and outside. A lock pin 30 is provided so as to project in the direction, and an inward projection of the lock pin 30 is slidably fitted in an elongated hole 26b formed in a substantially intermediate portion of the rotary lever 26 so as to be movable back and forth. Further, the tip of the lock pin 29 penetrates so that it can be selectively engaged and disengaged with a plurality of upper and lower locking step portions 31a of the lock plate 31 fixed to the front end of the outer surface of the upper frame 2. Has become. Further, a lock spring 32 is stretched between the outer protruding portion of the lock pin 29 and the guide pin 29, and the lock pin 29 locks the lock plate 31 with respect to the locking step portion 31a by this spring force. The lock lever 27 is always biased forward to hold it.

That is, the operating lever 24 is the lock pin 2
9 is locked by being locked to the locking step portion 31a of the lock plate 31, the rotation of the rotation lever 26 with respect to the upper frame 2 is restricted, and the interlocking pin 23 is moved integrally with the upper frame 2. To hold. Further, by pushing the lock lever 27 to move it backwards against the lock spring 32, the lock pin 29 is moved to the lock plate 3
1 is disengaged from the locking step portion 31a to be in the unlocked state,
In this state, if the rotary lever 26 is rotated in the vertical direction together with the lock lever 27, the lock pin 29 is locked to the other locking step portion 31a, and the locked position of the rotary lever 26 can be changed. In this way, by rotating the rotating lever 26 to change the lock position, the interlocking pin 23 moves on the circumference around the mounting pin 28 which is eccentric from the rotating center of the cam plate 22, that is, Within the engagement groove 22d of the cam plate 22, it is moved and adjusted obliquely with respect to the center line of the engagement groove 22d and positioned and held.

Thus, according to the vehicle seat air suspension apparatus having the above-described structure, the seat cushion moves from the position of the reference height Z in FIG. When descending together with the frame 2, the interlocking pin 23 and the cam plate 22 of the valve switching mechanism 20 descend together therewith, and at the same time, the supply / exhaust valves 7 and 8 rotate together with the link bar 3b to lie down. As a result, the cam plate 22 and the supply / exhaust valves 7 and 8 relatively move up and down,
The valve switching cam surface 22 on the upper end side of the cam plate 22
While a is joined to the valve rod 7a of the air supply valve 7, the cam plate 22 pivots upward so as to escape from the valve rod 7a by a distance equivalent to a traveling distance with respect to the interlocking pin 23 in the engagement groove 22d. When the seat cushion descends beyond the lower dead zone B, the rotation of the cam plate 22 is restricted by the interlocking pin 23, and the seat cushion descends as it is and the valve switching cam surface 22a of the upper portion causes the valve rod 7a of the air supply valve 7 to move. Is pressed to open the air supply valve 7, supply compressed air from the air supply source to the air spring 5, and pressurize the air spring 5 to push up the upper frame 2 to raise the seat cushion.

During this ascent, the valve switching mechanism 20 and the supply / exhaust valves 7, 8 relatively move in the opposite manner to the above, but the cam plate 22 reverses to the above, the interlocking pin in the engaging groove 22d. 23
By rotating the valve rod 7a downward by an amount equivalent to the travel distance, the valve switching cam surface 22a on the upper side keeps the valve rod 7a in a pressed-in state. As a result, when the air supply valve 7 does not close immediately and the upper frame 2 is further pushed up by the air spring 5 and the seat cushion returns to near the original reference height Z position, the rotation of the cam plate 22 causes the interlocking pin 23 to rotate. The upper valve switching cam surface 22a is disengaged from the valve rod 7a, the valve rod 7a automatically returns to close the air supply valve 7, the air supply to the air spring 5 is stopped, and the seat cushion returns to the original standard. It is returned and held at the height Z position.

Contrary to the last time, when the seat cushion rises from the reference height Z due to the seated person leaving the seat or the traveling vibration of the automobile, the valve switching mechanism 20 rises together with this. At the same time, the link bar 3b rotates so as to stand up. As a result, the valve switching mechanism 20 and the valve body 6 move vertically relative to each other, and while the cam switching plate 22a of the cam plate 22 is joined to the valve rod 8a of the exhaust valve 8 while the valve switching cam surface 22b is joined to the valve plate 8a. It pivots downward so as to escape from the valve rod 8a by the amount of the traveling distance with respect to the interlocking pin 23 in the engagement groove 22d. When the seat cushion descends beyond the upper dead zone A, the cam plate 22
Is restricted by the interlocking pin 23, and as it rises, the lower valve switching cam surface 22b pushes the valve rod 8a of the exhaust valve 8 to open the exhaust valve 8 and exhaust the compressed air in the air spring 5. To do. This pulls down the upper frame 2 to lower the seat cushion.

During this descending movement, the valve switching mechanism 20 and the supply / exhaust valves 7, 8 relatively move in the opposite manner to the above, but the cam plate 22 reversely moves the interlocking pin in the engaging groove 22d. 23
By rotating the valve rod 8a upward by an amount equivalent to the traveling distance with respect to, the state in which the valve rod 8a is pushed in by the lower valve switching cam surface 22b is maintained. As a result, when the upper frame 2 is further pulled down and the seat cushion returns to near the original reference height Z position without immediately closing the exhaust valve 8, the rotation of the cam plate 22 is restricted by the interlocking pin 23, and Of the valve switching cam surface 22b is removed from the valve rod 8a, the valve rod 8a automatically returns to close the exhaust valve 8, the exhaust from the air spring 5 stops, and the seat cushion returns to the original reference height Z position. Retained.

That is, in this vehicle seat air suspension device, even if the seat cushion moves up and down from the reference height Z position due to traveling vibration or the like, the upper and lower dead zones A,
The air spring 5 is not controlled by the supply / exhaust valves 7 and 8 in a range not exceeding B, and when the dead zones A and B are exceeded, the supply / exhaust valves 7 and 8 are selectively opened to open the air spring 5. The control is performed so that the seat cushion is always returned to the reference height Z.

Here, when the seat occupant changes the reference height Z of the seat cushion according to his or her preference, the operating lever 24 is turned up and down as described above, and the interlocking pin 2 is moved.
3 in the engagement groove 22d of the cam plate 22
The movement is adjusted in one or the other diagonal direction with respect to the center line of 2d. As a result, the cam plate 22 rotates so that the center line of the engaging groove 22d comes to the moved position of the interlocking pin 23, and the reference height Z of the seat cushion is adjusted up and down. At the same time, since the engaging groove 22d is V-shaped and the groove width increases from one end side to the other end side, the traveling distance of the interlocking pin 23 is as shown in a and b as shown in FIG. Then, the widths of the upper and lower dead zones A and B of the seat cushion are adjusted.

That is, the operation pin 24 is operated to operate the interlocking pin 2
If the reference height Z of the seat cushion is lowered by moving and adjusting 3 to reduce the width of the dead zones A and B. As a result, even if the standard height Z of the seat cushion is adjusted to be low in a seat where the seat height is low due to the vehicle space and the stroke of the suspension is not large, the dead zones A and B become narrower accordingly. The stroke required for the cushioning operation of the seat is not reduced so much, and the occurrence of bottoming due to vibration during traveling of the vehicle is reduced.

Next, another embodiment of the present invention will be described with reference to FIGS.
This will be described below. In the figure, the same components as those shown in FIGS. 1 to 3 are designated by the same reference numerals to simplify the description.

First, similar to the above-described embodiment, the valve switching mechanism 40 includes a substantially lateral T-shaped cam plate 42 for switching the supply / exhaust valves 7 and 8 between open and closed, and this cam plate 42.
And an interlocking pin 43 that interlocks with the upper frame 2,
An operation lever 44 for positioning and holding the interlocking pin 43 so that it can be moved and adjusted is provided.

Here, the cam plate 42 is rotatably mounted at its base end to a pivot pin 25 with the link bar 3b at the front end of the upper frame 2, and has valve switching cam surfaces 42a and 42b at the upper and lower ends on the tip side. Have. Also this cam plate 4
An engaging groove 42d, which is a substantially fan-shaped hole, is formed in a substantially intermediate portion of 2 so as to become wider from one end side to the other end side. That is, the engagement groove 42d has a shape that gradually expands in a tapered shape as it goes away from the pivot pin 25 which is the center of rotation of the cam plate 42.

The interlocking pin 43 is loosely inserted in the engagement groove 22d of the cam plate 42 in a state of being orthogonal to each other. The interlocking pin 43 is bent in a substantially Z shape, and its upper end is slidably penetrated into an elongated hole 45a of a lock plate 45 fixed to the upper surface of the upper frame 2. The long hole 45a is formed in the lock plate 45 in a forwardly inclined state. Further, a lock pin 46 is provided on the outer surface of the lock plate 45 so as to be located above the elongated hole 45a in a substantially extended line shape.

The operation lever 44 has a horizontal handle portion 44.
It is an elongated plate which is bent in a generally V-shape and has a plurality of upper and lower engaging step portions 44c ... At the inner edge of the oblique descending portion 44b. The lock plate 4 is attached to the lower end of the inclined portion 44b of the operation lever 44.
The upper end portion of the interlocking pin 43 passing through the elongated hole 45a of No. 5 is fixed. Further, the locking step portion 44c of the operating lever 44
... is the lock pin 46 of the lock plate 45 in the previous term
A lock spring 47 that can be engaged with and disengaged from and is retained in the locked state is stretched between the handle portion 44a of the operation lever 44 and the hole 45b of the lock plate 45.

That is, the operating lever 44 has the interlocking pin 43 penetrating the elongated hole 45a of the lock plate 45, the lock pin 46 locked by the locking step portion 44c, and the lock spring 47.
Thus, while being held in a locked state with respect to the upper frame 2, the interlocking pin 43 is fixedly held. Further, by manually turning the handle portion 44a of the operating lever 44 rearward against the lock spring 47, the locking step portion 44c is disengaged from the lock pin 46 and is in the unlocked state. In this state, Lock pin 4 by pulling it up diagonally or lowering it diagonally downward.
The other locking step portion 44c is locked to 6, and the lock position of the operation lever 44 can be changed diagonally up and down. By moving the operation lever 44 to change the lock position in this way, the interlocking pin 43 moves along the elongated hole 45a of the lock plate 45, that is, in the engagement groove 42d of the cam plate 42. 42d is moved and adjusted in an oblique direction with respect to the center line of 42d so as to be positioned and held. With this,
Even in the case of this embodiment, the same operational effects as those of the previous embodiment can be obtained.

It should be noted that the present invention is not limited to the above-described embodiment, but may be, for example, the supply / exhaust valves 7 and 8 and the valve switching mechanism 2.
In addition to the above-mentioned link bar 3b and upper frame 2, 0 and 40 are link bars 3a and 3 of the link mechanism 3 that are displaced relative to each other as the seat cushion moves up and down.
b, or the upper frame 2 and the link bar 3a, the lower frame 1 and the link bar 3a or 3b, or the lower frame 1 and the upper frame 2 may be attached to one or the other of the two members. Other various modifications can be made without departing from the scope of the present invention.

[0041]

Since the air suspension device for a vehicle seat of the present invention is constructed as described above, it has a very simple construction, and at the same time as adjusting the reference height of the seat cushion, it is possible to reduce the width of the upper and lower dead zones. For seats that can be adjusted and the seat height is low due to the vehicle space and the stroke of the suspension is not large, even if the standard height of the seat cushion is set low, the dead zone width can be reduced accordingly, so the seat cushion The stroke required for operation can be sufficiently secured, bottoming can be prevented, and excellent cushioning performance with a comfortable ride can be maintained.

[Brief description of drawings]

FIG. 1 is a side view of an air suspension device according to an embodiment of the present invention.

FIG. 2 is an operation explanatory view of the valve switching mechanism of the above embodiment.

FIG. 3 is an exploded perspective view of a valve switching mechanism of the above embodiment.

FIG. 4 is a side view of a valve switching mechanism and a supply / exhaust valve according to another embodiment of the present invention.

FIG. 5 is an operation explanatory view of the valve switching mechanism of the above embodiment.

FIG. 6 is an exploded perspective view of the valve switching mechanism of the above embodiment.

FIG. 7 is a perspective view of a conventional air suspension device.

FIG. 8 is a side view of the valve switching mechanism and the supply / exhaust valve of the conventional example as above.

[Explanation of symbols]

1 …… Lower frame, 2 …… Upper frame, 3 ……
Link mechanism, 5 ... Air spring, 7 ... Air supply valve, 8 ... Exhaust valve, 20 ... Valve switching mechanism, 22, 42 ... Cam plate, 22a, 22b, 42a, 42b ... Valve switching cam surface , 22d, 42d ... engaging groove, 23, 43 ... interlocking pin, 24, 44 ... operating lever, Z ... standard height of seat cushion, A, B ... dead band.

Claims (1)

(57) [Scope of utility model registration request] 1. A lower frame fixed on a floor of a vehicle,
An upper frame that is disposed above the lower frame to support a seat cushion of a vehicle seat, a link mechanism that supports the upper frame so that the upper frame can move up and down with respect to the lower frame, and an air spring that supports a load generated in the upper frame. , A supply / exhaust valve for supplying air to the air spring from an air supply source or exhausting air from the inside of the air spring, and the supply / exhaust valve when the seat cushion moves up and down from a reference height to exceed a predetermined dead zone. An air suspension device for a vehicle seat, comprising: a valve switching mechanism for returning the seat cushion to a reference height by selectively opening an exhaust valve to control an air spring internal pressure. One of the two members, the link mechanism, the upper frame, and the lower frame, that are displaced relative to each other. Of the supply and exhaust valves provided in the member, providing a valve switching mechanism faces the fed-and exhaust valves on the other member,
This valve switching mechanism is rotatably pivotally attached to the other member, has valve switching cam surfaces on both end portions, and has an engagement groove whose groove width increases from one end side to the other end side. The cam plate, the interlocking pin loosely inserted in the engagement groove of the cam plate, and the interlocking pin attached to the other member in the engagement groove of the cam plate with respect to the center line of the engagement groove. The operating height of the seat cushion is adjusted so that the seat cushion reference height can be lowered by adjusting the movement of the interlocking pin by operating this operation lever. An air suspension device for a vehicle seat characterized by the following settings.