JP3205355B2 - Level control device for anti-vibration support frame - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an anti-vibration frame level control device, and more particularly to an anti-vibration bed mounted on an emergency vehicle to mount a stretcher or stretcher for carrying an injured person. The present invention relates to a device for controlling the level of an anti-vibration frame provided in order to increase the level of vibration.

[0002]

2. Description of the Related Art A rescue bed has a frame supported on a base via an air spring, a gantry is supported on the frame via a laminated rubber, and a stretcher for carrying a patient is placed on the gantry. It was developed and exhibited as a reference at the 18th Annual Meeting of the Japanese Association for Emergency Medicine (Kurashiki City, Okayama Prefecture, November 8-10, 1990). In this bed for rescuers, the air spring supporting the frame absorbs the vertical vibration, and the laminated rubber supporting the gantry absorbs the front-back, left-right vibration, and enables the patient to be transported at ease. I do.

[0003]

The spring constant of the air spring supporting the frame is preferably soft in order to cope with the vertical vibration, but on the other hand, if the spring constant of the air spring is set soft. Depending on the weight of the victim, the level of the frame, and thus the level of the bed, is likely to change. As a result, when the weight of the patient is heavy, the level of the frame goes down and bottoms out. Conversely, when the weight of the patient is light, the level of the frame goes up. Cannot be fully demonstrated.

It is an object of the present invention to provide an apparatus for controlling the level of a frame provided with a frame supported on a base via an air spring, such as the emergency rescue isolator bed. is there.

[0005]

SUMMARY OF THE INVENTION The present invention is an apparatus for controlling the level of a frame supported on a base via an air spring having an air chamber which expands and contracts in a vertical direction. A first cam for the upper level and a second cam for the lower level are mounted on the frame. A first valve is incorporated in a first tube for opening the air chamber to the atmosphere. The first valve has a spool that engages with the first cam to enter and exit, and controls communication and shutoff between the air chamber and the atmosphere by the spool. A second valve is incorporated in a second tube for supplying compressed air from a pressure source to the air chamber. The second valve has a spool that engages with the second cam to enter and exit, and controls communication and shutoff between the pressure source and the air chamber by the spool.

[0006] The pressure in the air chamber of the air spring is such that the level of the frame is at a height in a predetermined range, at which height the first and second valves are operated by a first cam and a second cam, respectively. Is determined so as not to engage with.

When the load applied to the frame is reduced, the frame is raised, and the spool of the first valve is engaged with the first cam. As a result, the air chamber communicates with the atmosphere, so that the compressed air escapes from the air chamber to the atmosphere, the pressure in the air chamber decreases, and the frame lowers.

Conversely, when the load applied to the frame increases, the frame descends and the spool of the second valve engages with the second cam. Thereby, as a result of the pressure source communicating with the air chamber, compressed air is supplied to the air chamber, the pressure in the air chamber increases, and the frame rises.

[0009] Regardless of the magnitude of the load applied to the frame, the level of the frame can be maintained at a fixed height within a predetermined range, so that the vertical stroke of the frame is secured within an optimum range, and the vibration isolation performance of the frame is improved. It is maximized.

A third valve incorporated in the first tube having a spool biased toward a closed position, wherein the air chamber is in the open position when the spool of the third valve is in an open position; A third valve that allows communication between the air and the atmosphere.

When the load applied to the frame is displaced upward, for example, according to the running of the vehicle, the upward displacement or stroke may cause the first valve to engage with the first cam. sell. Without the third valve, the compressed air would escape immediately, but as a result of the provision of the third valve, the compressed air would not escape from the air chamber to the atmosphere unless the spool of the third valve was in the open position. Thus, by providing the third valve, frequent escape of the compressed air can be prevented.

A fourth valve incorporated in said second tube having a spool biased toward a closed position, said pressure source being provided when said spool of said fourth valve is in an open position; A fourth valve that allows communication between the air chamber and the air chamber.

When the load applied to the frame is displaced downward, for example, according to the running of the vehicle, the second displacement may cause the second valve to engage with the second cam due to the downward displacement or stroke. sell. Without the fourth valve, compressed air would be supplied immediately, but the provision of the fourth valve would result in compressed air being supplied to the air chamber unless the spool of the fourth valve was in the open position. Absent. Thus, by providing the fourth valve, frequent supply of compressed air can be prevented.

Therefore, in a case where the load in the vertical direction is repeatedly applied to the frame, if the third valve and the fourth valve are provided, the flow of the compressed air from the air chamber and to the air chamber can be improved. Frequency can be reduced. In addition, the raising and lowering of the frame can be artificially operated according to the load.

When the third valve and the fourth valve are provided, the third valve
And the fourth valve are preferably configured to be operated simultaneously by common means.

Even when the third valve and the fourth valve are provided,
Although it is possible to operate these valves individually, their operation requires a determination whether the frame is raised or lowered, and then the corresponding valves must be selected. However, if the third valve and the fourth valve are operated simultaneously, the first valve engaged with the first cam or the second valve engaged with the second cam Can be activated to release compressed air to the atmosphere or to supply air to the air chamber to keep the frame at a predetermined range of levels. Thus, the operation is simplified.

[0017] Preferably, the air spring includes a sub-tank having an air chamber communicating with the air chamber. This makes it possible to reduce the volume of the air chamber of the air spring, so that the installation height of the frame can be reduced accordingly. Also,
The variable range of the spring constant of the air spring can be expanded.

The present invention also provides at least one first air spring having a vertically extending and contracting air chamber and at least one rearwardly extending first air spring having a vertically expanding and contracting air chamber. A device for controlling the level of a frame supported on a base via two air springs. A first cam for the upper level and a second cam for the lower level
Are mounted on a front portion of the frame. A third cam for the upper level and a fourth cam for the lower level are attached to a rear portion of the frame. A first valve is incorporated in a first pipe for opening the air chamber of the first air spring to the atmosphere. The first valve has a spool that engages with the first cam and moves in and out.
Of the air chamber and the atmosphere of the air spring are controlled. A second valve is incorporated in a second tube for supplying compressed air from a pressure source to the air chamber of the first air spring. The second valve has a spool that engages with the second cam and moves in and out, and controls communication and shutoff between the pressure source and the air chamber of the first air spring by the spool. A third valve is incorporated in a third pipe for opening the air chamber of the second air spring to the atmosphere. The third valve has a spool that engages with the third cam and moves in and out, and controls communication and shutoff between the air chamber of the second air spring and the atmosphere by the spool. A fourth valve is incorporated in a fourth tube for supplying compressed air from a pressure source to the air chamber of the second air spring. The fourth valve has a spool that engages with the fourth cam and moves in and out, and controls communication and shutoff between the pressure source and the air chamber of the second air spring by the spool.

The operation is basically the same as described above, but in the present invention, the levels of the front part and the rear part of the frame are controlled independently. This enables fine level control.

When the front portion of the frame is supported by a first air spring and the rear portion is supported by a second air spring, it is incorporated into said first tube having a spool biased toward a closed position. A fifth valve, wherein when the spool of the fifth valve is in the open position, the first valve
A fifth valve for allowing communication of the air chamber of the air spring with the atmosphere, and a sixth valve incorporated in the second tube having a spool biased toward a closed position. A sixth valve for allowing communication between the pressure source and the air chamber of the first air spring when the spool of the sixth lever is in the open position; and a sixth valve biased toward the closed position. A seventh valve incorporated in said third tube, said spool having an open spool when said spool of said seventh valve is in an open position. An eighth valve incorporated in said fourth tube having a seventh valve allowing communication of the valve and a spool biased toward a closed position, wherein said spool of said eighth valve is When in the open position, allows communication between the pressure source and the air chamber of the second air spring. Preferably includes a 8 of the valve.
In this case, the fifth valve and the sixth valve are simultaneously operated by common means, and the seventh valve and the eighth valve are operated simultaneously.
It is convenient to operate these valves simultaneously by common means.

When the first to eighth valves are included, it is preferable to include another frame which is supported by the frame and is disposed above the frame. The stretcher can be placed on this other frame or on a cover over the other frame. In this case, if the pressure source is formed by a tank filled with compressed air, it is not necessary to provide the ambulance with a pressure source such as a compressor.

[0022]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention is basically an apparatus for controlling the level of a frame supported on a base via an air spring having an air chamber which expands and contracts in a vertical direction. By supporting one end of the frame with the air spring and the other end of the frame with another air or coil spring, or by pivoting with a pin;
The present invention can be implemented. A first cam and a second cam are attached to a portion of the frame supported by the air spring, and a valve having a spool which engages with each cam and moves in and out is arranged. One valve is for opening to the atmosphere, and the other valve is for supplying compressed air.

Shown in the drawing is a preferred embodiment of the present invention applied to an anti-vibration bed of an ambulance, wherein the level control device has at least one frontly disposed air chamber having an air chamber which expands and contracts in a vertical direction A. Controlling the level of a frame 16 supported on a base 14 via a first air spring 10 and at least one rearwardly arranged second air spring 12 having an air chamber that expands and contracts in a vertical direction A .

In the embodiment shown in FIG.
A base 14 is formed by two air springs 10 arranged on the front left and right and two air springs 12 arranged on the rear left and right.
Supported above. The air springs 10 and 12 are known per se having an expanding and contracting air chamber, and are positioned so that each air chamber expands and contracts in the vertical direction. A link 18 is swingably connected to the base 14, and another link 20 is swingably connected to the link 18. The link 20 is swingably connected to the frame 16 so that the frame 16 can be displaced in the vertical direction A.

In the embodiment shown in FIG.
It comprises a front portion 16a, a pair of side portions 16b extending rearward from the front portion 16a, and a rear portion (not shown). Each part is formed of a hollow steel material having a closed cross section, and the plane shape of the frame 16 is rectangular as a whole. Two brackets 16c are provided at two ends of the front portion 16a, respectively, and the air spring 10 is mounted between the bracket 16c and the base 14. The rear part has the same structure.

A first cam 22 for the upper level and a second cam 24 for the lower level are mounted on the front portion 16a of the frame 16, as shown in FIG. Similarly, a third cam for the upper level and a fourth cam for the lower level
Are attached to the rear portion of the frame 16. In the illustrated embodiment, the first cam 22 and the second cam 24 are of the same shape having an inclined cam surface 23 at one end, and are arranged so that the cam surfaces 23 are opposite to each other.
The two cams 22, 24 are mounted on the front part 16a. The third cam has the same shape and the same arrangement as the first cam 22, and the fourth cam has the same configuration as the second cam 24.

In the embodiment shown in FIGS. 4 and 5, a gate-shaped stopper 26 is fixed to the base 14, and the front portion 16a of the frame 16 is surrounded by the stopper 26.
The rear part of the frame 16 is formed similarly. This restricts the upward movement of the frame 16 and prevents the frame 16 from hitting another frame 28 described later. Further, a pair of guides 30 are attached to the stopper, and are in contact with front and rear surfaces of the front portion 16 a of the frame 16. By this guide 30, the frame 1
6 is prevented from swinging back and forth.

As shown in FIG. 1, a first valve 34 is incorporated in a first pipe 32 for opening the air chamber 11 of the first air spring 10 to the atmosphere. The first valve 34 is a normally-closed two-port valve in the illustrated embodiment, and has a spool 35 which engages with the first cam 22 and moves in and out. Of the air chamber 11 and the atmosphere is controlled. Cam 2 of spool 35
In order to facilitate the engagement with the spool 2, it is preferable to form a so-called limit valve so that the spool 35 is operated by the lever 33 (see FIG. 4).

In the embodiment shown, tube 32, on the other hand,
Pipe 36, sub-tank 38 with air chamber 39 and pipe 4
0 is connected to the air chambers 11 of the two air springs 10, and the other is connected to a fifth valve 42 as described later.

A second tube 46 for supplying compressed air from the pressure source 44 to the air chamber 11 of the first air spring 10
A second valve 48 is incorporated. The second valve 48 is a normally-closed two-port valve like the first valve 34,
And a spool (not shown) which engages with the cam 24 and controls the communication and cutoff between the pressure source 44 and the air chamber 11 of the first air spring 10.

In the embodiment shown, tube 46, on the other hand,
It is connected to a pressure source 44 via a sixth valve 50, a pipe 52 and a pipe 54, which will be described later, while the pipe 36, the sub tank 3
8 and the air chamber 1 of the two air springs 10 via the tube 40
1 connected. Therefore, the pipe 36 to the two air springs 10 are common to the pipe 32. This is because the two valves 34, 48 do not operate at the same time.

A third valve 58 is incorporated in a third pipe 56 for opening the air chamber 13 of the second air spring 12 to the atmosphere. The third valve 58 is a normally-closed two-port valve similar to the first valve 34, and has a spool (not shown) that engages with the third cam and moves in and out. The communication between the air chamber 13 of the second air spring 12 and the atmosphere and the atmosphere are controlled.

In the embodiment shown, tube 56, on the other hand,
Pipe 60, sub-tank 62 having air chamber 63 and pipe 6
4 is connected to the air chambers 13 of the two air springs 12, while the other is connected to a seventh valve 66 as described later.

A fourth tube 70 for supplying the compressed air from the pressure source 44 to the air chamber 13 of the second air spring 12 has:
A fourth valve 72 is incorporated. The fourth valve 72 is a normally-closed two-port valve similar to the first valve 34, and has a spool (not shown) that engages with the fourth cam and moves in and out. The communication between the source 44 and the air chamber 13 of the second air spring 12 is controlled and shut off.

In the embodiment shown, the tube 70, on the other hand,
It is connected to the pressure source 44 via an eighth valve 74, a pipe 76 and a pipe 54 which will be described later, while the pipe 60, the sub tank 6
2 and air chamber 1 of two air springs 12 via tube 64
3 is connected. Therefore, the pipe 76 is branched from the pipe 54 in the direction opposite to the pipe 52, and the pipe 60, the sub tank 62 and the pipe 64 are common to the pipe 56.

The fifth valve 42, like the first valve 34, is a normally closed, ie, two-port, valve having a spool (not shown) biased toward the closed position. Fifth valve 4
Numeral 2 is incorporated in the first tube 32 and enables communication between the air chamber 11 of the first air spring 10 and the atmosphere when the spool is in the open position. In other words, the air chamber 11 of the air spring 10 communicates with the atmosphere when the spool 35 of the first valve 34 is in the open position and the spool of the fifth valve 42 is in the open position.

The sixth valve 50, like the first valve 34, is a normally closed, ie, two-port, valve having a spool (not shown) biased toward the closed position. Sixth valve 5
0 is incorporated into the second tube 46 to allow communication between the pressure source 44 and the air chamber 11 of the first air spring 10 when the spool is in the open position.

The seventh valve 66 is a two-port valve having a spool (not shown) that is normally closed like the first valve 34, that is, biased toward the closed position. Seventh valve 6
6 is incorporated in the third tube 56 to enable communication between the air chamber 13 of the second air spring 12 and the atmosphere when the spool is in the open position.

The eighth valve 74 is a two-port valve having a spool (not shown) that is normally closed like the first valve 34, that is, biased toward the closed position. Eighth valve 7
4 is incorporated in the fourth tube 70 to enable communication between the pressure source 44 and the air chamber 13 of the second air spring 12 when the spool is in the open position.

In the illustrated embodiment, the fifth valve 42 and the sixth valve 50 are assembled as a pair, and both spools are operated by a common push button 43. Further, the seventh valve 66 and the eighth valve 74 are assembled as a pair, and the spools of the two are shared by a common push button 6.
7 is operated.

Further, in the illustrated embodiment, the frame 28
Are supported on the frame 16 by four sets of laminated rubbers 80 and are disposed above the frame 16. The laminated rubber 80 absorbs vibration in the front-back direction B and the left-right direction. A shock absorber 82 is mounted between the frame 28 and the link 18 to dampen the vertical vibration of the frames 16, 80. The pressure source 44 is a tank filled with compressed air.

The frame 16, which is supported as described above,
An anti-vibration bed is constituted by 28, and is used as an anti-vibration bed for an ambulance by fixing the base 14 to the floor of the vehicle. The stretcher is mounted and secured directly to the frame 28 and to a suitably positioned cover. A pressure gauge 90 is attached to the tank 44 so that a pipe 92 connected to an external compressor can be connected to and disconnected from the tank 44 so that compressed air can be supplied.

[Brief description of the drawings]

FIG. 1 is a schematic view of a level control device of an anti-vibration support frame according to the present invention.

FIG. 2 is a side view of an anti-vibration bed incorporating an anti-vibration support frame.

FIG. 3 is a plan view of the anti-vibration bed shown in FIG. 2;

FIG. 4 is a side view showing a cross section of a part of a frame, a cam attached to the frame, and a valve.

FIG. 5 is a perspective view of the frame, cam and valve shown in FIG. 4;

[Explanation of symbols]

 10, 12 Air spring 14 Base 16, 28 Frame 22, 24 Cam 34, 48, 58, 72 Valve

──────────────────────────────────────────────────続 き Continued on the front page (58) Fields surveyed (Int. Cl. ⁷ , DB name) A61G 1/00-3/00 A61G 7/00 F16F 9/04 F16F 15/04

Claims (8)

(57) [Claims] 1. An apparatus for controlling the level of a frame supported on a base via an air spring having an air chamber which expands and contracts in a vertical direction, wherein the first cam for an upper level is mounted on the frame. A second cam for the lower level attached to the frame, and a valve incorporated in a first pipe for opening the air chamber to the atmosphere, the second cam being engaged with the first cam. A first valve having an inlet / outlet spool for controlling communication and shutoff between the air chamber and the atmosphere by the spool; and a second pipe for supplying compressed air from a pressure source to the air chamber. A second valve that has a spool that engages and exits the second cam and controls communication and shutoff between the pressure source and the air chamber by the spool. Level control device for vibration support frame. 2. The apparatus of claim 1, further comprising a third valve integrated with said first tube having a spool biased toward a closed position, said spool of said third valve being in an open position. The communication between the air chamber and the atmosphere is enabled.
5. The level control device for an anti-vibration support frame according to 4. 3. The system further includes a fourth valve integrated with the second tube having a spool biased toward a closed position, the spool of the fourth valve being in an open position. 2. The level control device for an anti-vibration support frame according to claim 1, wherein communication between the pressure source and the air chamber is enabled. 4. A third valve incorporated in said first tube having a spool biased toward a closed position, said spool of said third valve being in an open position. A third valve for allowing communication between the air chamber and the atmosphere, and a spool biased toward a closed position.
A fourth valve incorporated in the second tube, the fourth valve allowing communication between the pressure source and the air chamber when the spool of the fourth valve is in an open position; 2. The level control device for an anti-vibration support frame according to claim 1, wherein the third valve and the fourth valve are simultaneously operated by common means. 3. 5. The level control device for an anti-vibration support frame according to claim 1, further comprising a sub tank having an air chamber communicating with the air chamber of the air spring. 6. At least one first air spring disposed forward and having an air chamber that expands and contracts vertically, and at least one second air disposed rearward that has an air chamber that expands and contracts vertically. Apparatus for controlling the level of a frame supported on a base via a spring, wherein a first for an upper level mounted on a forward portion of said frame.
A second cam for a lower level attached to a front portion of the frame, a third cam for an upper level attached to a rear portion of the frame, and a third cam attached to a rear portion of the frame. A fourth cam for the lower level and a valve incorporated in a first tube for opening the air chamber of the first air spring to the atmosphere,
A first valve for controlling communication and shutoff between the air chamber of the first air spring and the atmosphere by the spool, and a compressed air from a pressure source. A valve incorporated in a second tube for supplying the air chamber of the first air spring, the spool engaging and disengaging with the second cam, and the pressure source is provided by the spool. And a second valve for controlling communication and shutoff of the first air spring with the air chamber, and a third pipe for opening the air chamber of the second air spring to the atmosphere. A third valve which has a spool which engages with the third cam to enter and exit, and which controls communication and shutoff between the air chamber and the atmosphere of the second air spring by the spool.
And a valve incorporated in a fourth pipe for supplying compressed air from a pressure source to the air chamber of the second air spring, which engages with the fourth cam to enter and exit. A level control device for an anti-vibration support frame, comprising: a fourth valve having a spool for controlling communication and shutoff between the pressure source and the air chamber of the second air spring by the spool. 7. A fifth valve incorporated in said first tube having a spool biased toward a closed position, said spool of said fifth valve being in an open position. A fifth valve incorporated in the second tube having a fifth valve for allowing communication between the air chamber of the first air spring and the atmosphere, and a spool biased toward a closed position. A sixth valve that allows communication between the pressure source and the air chamber of the first air spring when the spool of the sixth valve is in the open position; A seventh valve integrated into the third tube having a spool biased toward the third tube, the air of the second air spring when the spool of the seventh valve is in an open position. A seventh valve for allowing communication between the chamber and the atmosphere, and a spool biased toward a closed position. Connecting the pressure source to the air chamber of the second air spring when the spool of the eighth valve is in an open position. And the fifth valve and the sixth valve are operated simultaneously by common means, and the seventh valve and the eighth valve are common. 7. The level control device for a vibration isolating support frame according to claim 6, wherein the level control device is operated simultaneously by the means. 8. An anti-vibration support by said frame,
8. A system according to claim 7, further comprising another frame disposed above said frame, wherein said pressure source is a tank filled with compressed air.
5. The level control device for an anti-vibration support frame according to 4.