JPH0622513B2 - Anti-vibration device for beds in emergency vehicles - Google Patents

Description

The present invention relates to a vibration damping device for a bed mounted on an ambulance.

[Conventional technology]

For example, Japanese Patent Application Laid-Open No. 1-192353 discloses a vibration isolation device for a stretcher. This anti-vibration device has a bent portion of two V-shaped arms horizontally rotatably provided in the center upper part of the base so as to be rotatable in an X shape, and a roller rotatably supported at the upper end thereof supports a frame for mounting a stretcher. At the same time, an intermediate link is pivotally supported between the center of the frame and the intermediate portion of one arm so that the frame can be moved up and down. In addition, a compression spring and a hydraulic cylinder are pivotally supported between the lower end of each arm and the front and rear ends of the base, and a damper is pivotally supported between the base and the middle of each arm to provide a drive system and a vibration isolation structure. Are configured. Then, when it is desired to lower the frame to the lower limit position, both hydraulic cylinders are contracted against the spring force, and when one wants to tilt forward and backward, one hydraulic cylinder is contracted and the other hydraulic cylinder is expanded.
Further, when it is desired to bring the floating state, that is, the state in which the anti-vibration function can be exerted, the switching valves are switched so that the piston side chamber and the rod side chamber of each hydraulic cylinder communicate with each other.

[Problems to be Solved by the Invention]

By the way, the above-mentioned anti-vibration device is satisfactory because it is equipped with a low-floor stretcher with fixed legs, but there are also high-floor stretchers that can bend legs. There is a need to be able to mount a stretcher on an anti-vibration device. Of course, if a part of the frame of the anti-vibration device is improved, it is possible to mount a high floor type, but in that case the total height when the stretcher is mounted is large, so lower the frame to the lower limit position and strike. There are problems that it is difficult to load and unload the letcher, it is difficult to treat the patient, and the ceiling of the vehicle approaches the patient and gives a feeling of pressure.

Further, when it is desired to lower the frame to the lower limit position, if the hydraulic pump or the like fails, it is almost impossible to forcibly lower the frame against the force of the compression spring, and the loading and unloading of the stretcher is extremely difficult. It will be difficult. Further, when the vehicle is braked, the front part of the frame (the patient's head) is lowered, which gives the patient discomfort.

Furthermore, although the damper is a hydraulic type, the function can be included in the hydraulic cylinder to eliminate the damper.
In that case, it becomes necessary to employ a spool type switching valve. Then, even if it is desired to hold the frame at the lower limit position, there is a risk that the frame gradually rises due to oil leakage of the spool type switching valve.

The present invention has been made in view of the above circumstances, and it is possible to lower the overall height at the frame lower limit position, and to easily force the frame to descend without using a hydraulic cylinder. In order to prevent the patient's head from lowering, and also when the frame starts to rise due to the oil leak of the spool type switching valve, it is possible to lower the frame to the lower limit position again. To aim.

[Means for Solving the Problems]

In order to achieve the above object, a bed vibration damping device in an ambulance of the first extinction has two arms arranged on a base placed on a vehicle, and the upper end of the arm is lifted up and down with the lower end of the arm being a base. Each of them is supported by a frame, and the lifting frame can be raised and lowered by swinging about the support shaft on the base of the arm, and the lower part of the bed mounted in the ambulance is supported and locked by the lifting frame, A pair of hydraulic cylinders that double as a compression spring and a damper for absorbing the vibration are provided between the middle portion of each arm and the base, and the base side end of the compression spring is provided. The gist of the present invention is that the spring pressure of the compression spring can be adjusted by supporting the above with a base via a movable bracket.

Further, the second aspect of the present invention is summarized in that, in the bed vibration isolator of the first aspect of the present invention, two arms are combined in a V shape.

The third aspect of the present invention is the vibration damping device for a bed in an ambulance according to the first or second aspect, wherein a guide roller is provided at an upper end of the arm, and the guide roller is partially or wholly horizontal with respect to the elevating frame. The gist of the invention is that it is supported by an inclined guide rail, and the lifting frame is held substantially horizontally during braking.

Further, the fourth invention compensates for an oil leak of the spool type solenoid valve in the hydraulic circuit for operating the damper which also functions as the hydraulic cylinder in the bed vibration isolator of the first, second or third invention. As described above, a switch for detecting the swing angle of the arm is provided, and a reinforcement circuit for operating the hydraulic pump by the output of the switch is provided so that the stretcher on the elevating frame can always be held at the lower limit position. And

〔Example〕

An anti-vibration device for a head (stretcher) of the present invention will be described below based on the illustrated embodiment.

In the figure, C is an ambulance, S is a stretcher that can be installed in the ambulance C, V is an anti-vibration device that is installed on the side of the ambulance and supports the stretcher that is installed so as not to transmit the vibration of the ambulance to the stretcher. As the ambulance C, a conventionally used one-box car or station wagon is used.

The stretcher S is provided with a caster leg at the bottom of a bed having a required size, and the caster leg is a foldable type if necessary, and has a general-purpose structure.

As shown in FIGS. 1 and 2, the vibration isolator V has an elevation frame 2 for supporting a base 1 fixed at a predetermined position of an ambulance C and a stretcher S arranged on the base 1 as shown in FIGS. And two arms 3 and 4 which form a V-shape for connecting the base 1 and the lifting frame 2 and the arms 3 and 4.
Is oscillated so as to change the angle of the V-shape with a support shaft on the base at the lower end as a fulcrum, and a hydraulic cylinder 8 that doubles as a compression spring 7 and a damper for absorbing the vibration (hereinafter simply referred to as "hydraulic cylinder 8"). .).

Bearings 5 and 5 arranged on both sides of the center of the base 1 in the longitudinal direction
At the center of the base 1 is a single shaft 6 that is rotatably supported across
The base ends of the two arms 3 and 4 are formed into V-shapes via bearings, and each arm is swingably supported in opposite directions with the shaft 6 as a fulcrum.
The tips of the pair of arms 3 and 4 are formed so as to project in a V-shape obliquely upward in opposite directions.

A compression spring 7 is provided between the arm 3 and the base 1 on the side surface of the middle portion of the arm 3, and a hydraulic cylinder 8 is similarly provided between the arm 3 and the base 1 on the opposite side surface. Is provided so that the compression spring 7 and the hydraulic cylinder 8 act. Similarly, the compression spring 7 and the hydraulic cylinder 8 are also arranged on the other arm 4 on the side surface of the central part of the arm, but two arms 3, which are V-shaped, are provided.
The compression spring 7 and the hydraulic cylinder 8 of No. 4 are arranged symmetrically to each other, that is, as shown in FIG. Therefore, the load applied to the tip ends of the arms 3 and 4 simultaneously acts on the compression spring 7 and the hydraulic cylinder 8, and the two arms 3 and 4 swing by using the shaft 6 as a fulcrum by the operation of the hydraulic cylinder. Eggplant

The compression spring 7 protrudes from the mounting shaft 9 protruding from the arm so that the compression spring 7 is supported at a predetermined position between the arms and the base even if the arms 3 and 4 swing. It is supported by the movable bracket 10 provided. The compression spring 7 is attached to a bracket 7a supported by a mounting shaft 9 and a bracket 7b supported by a movable bracket 10, and spring holders 7c and 7b.
And a guide rod 7e projecting from the spring receiver 7c is slidably fitted in a guide cylinder 7g provided on the other spring receiver 7d, and faces the outer circumference of the guide lot 7e and the guide cylinder 7g. A coil spring 7f is arranged between both spring receivers 7c and 7d so as to receive spring pressure.

In the movable bracket 10 that supports the compression spring 7 on the base 1, a plurality of guide rods 10a are slidably fitted on a horizontal rail horizontally mounted on the base 1, and the base end of the guide rod 10a is fixed to the bracket body 10b. The bracket 7b is adjustably fixed, and the bracket 7b on the compression spring side is supported by the shaft 10c on the bracket body 10b.
A stopper 10d is formed at the tip of 0a, and the movable bracket 10 is supported by the base 1 so as to be movable in the longitudinal direction of the base only by the length of the guide rod 10a.

Therefore, when the base side fulcrum of the compression spring 7 is fixed, the stopper 10d is used, and the spring pressure of the compression spring 7 is adjusted by adjusting the stopper 10d. If it becomes impossible, loosening the stopper 10d moves the movable bracket 10 toward the outer end side of the base, and the compression force of the compression spring 7 is released.
4 can be swung to lower the elevating frame 2.

The hydraulic cylinder 8 has its base end side supported by a bracket 8a protruding from the base 1, and the cylinder rod 8b at the other end supported by the arms 3 and 4.

The elevating frame 2 is formed in a size suitable for supporting the stretcher S, and guide rails G, G are provided on both sides of the elevating frame 2, and the guide rails G, G facing each other are provided.
A shaft 11 is bridged between G, and guide rollers 12 and 12 provided at the end of the shaft 11 are supported by the guide rails G and G, respectively, and the shaft 11 is locked to the tips of the arms 3 and 4, that is, The shaft 11 is penetrated and supported at the tip of the arm. As a result, when the arms 3 and 4 swing, the arm tip position moves along the guide rails G and G by drawing an arc shape with the length of the arms 3 and 4 as a radius around the shaft 6. The guide rollers 12 and 12 move, whereby the tilting movement of the arms 3 and 4 causes the lifting frame 2 to move.
Make sure to move up and down smoothly.

Further, only by the relationship between the guide rail G and the guide roller 12, even if the elevating frame 2 is smoothly moved up and down, only the distance along which the guide roller moves within the allowable range,
The elevating frame 2 is free to move in the front-rear direction (longitudinal direction). In order to keep the movement of the lifting frame within the allowable range, one link 13 is bridged between one of the arms and the lifting frame. One end of the link 13 is pivotally supported by the lifting frame at a position above the vertical line of the shaft 6, and the other end of the link 13 is pivotally supported by a part of the arm. Make the spans an isosceles triangle. As a result, when the raising and lowering frame 2 moves up and down by the swinging (tilting movement) of the arms 3 and 4, the raising and lowering frame 2 is restricted by the link 13 and moves up and down on the same vertical line, in the longitudinal direction of the frame. It is possible to prevent more than the allowed movement.

As yet another embodiment, as shown in FIG.
Instead of 3, the spring cylinder 13a is pivotally supported, the elevating frame 2 is configured to be slightly movable back and forth regardless of the swing of the arms 3 and 4, and the guide rail G is on the head side (the traveling direction side of the vehicle). Is bent lower than the foot side or is supported by the elevating frame 2 with an inclination angle so that the elevating frame moves a predetermined allowable distance on the arms 3 and 4 during braking of the vehicle, It is also possible to hold the stretcher on the elevating frame 2 horizontally or in a slightly raised position.

Further, locking devices 14 for locking the stretcher S are provided on both upper surfaces of one end of the lifting frame 2. This locking device has a fixed hook 14a having an inverted L-shape and a movable hook 14b that opposes and closes the opening of the fixed hook 14a.
Is a pair in the front-rear direction, and the fixed hook 14a has a shape that is always open toward the direction in which the stretcher S is inserted, and is fixed to both left and right upper surfaces of one end of the elevating frame 2. The cross rails of the stretcher S are fitted and locked at 14a, 14a, which locks the stretcher S in the vertical direction and the depth direction. Is not locked and becomes free, but it is locked by the movable hook 14b.

The movable hook 14b is swingably supported by a bracket projectingly provided on the elevating frame 2 via a shaft, and links 14c are attached to the left and right movable hooks 14b and 14b, so that the shaft 14d is erected on the elevating frame. Bell cranks 14e are provided at both ends of the bell crank, the lower end of the link 14c is pivotally attached to one end of the bell crank 14e, and one end of a hook opening / closing wire or a rod 15 is locked to the other end of the bell crank. Alternatively, the tip of the rod 15 is guided along the elevating frame 2 to the front part of the frame, and the operation handle H is provided on this. Therefore, the movable hook 14 is always closed with a spring to close the opening of the fixed hook, but when the operation handle H is pulled, the movable hook 14b is connected via the wire or rod 15, the bell crank 14e, and the link 14c. By swinging, the fixing hook 14a is fully opened, and the stretcher can be removed from the lifting frame. When the stretcher is pushed along the lifting frame, the movable hook 14b is pushed down and automatically locked.

A hydraulic circuit as shown in FIG. 3 is configured in the hydraulic cylinders 8 and 8 for rocking (tilting) the two arms 3 and 4 combined in a V shape. This is because the hydraulic oil is supplied from the oil tank 20 to the valve unit 22 via the hydraulic pump 21, and the valve unit 22 intermittently sends the controlled hydraulic oil to the bottom side and the top side of each hydraulic cylinder 8, 8. ₂ solenoid valves SV ₁ and SV ₂ with check valves are arranged in series to form a pair, and valve circuits P ₁ , P ₂ , P ₃ and P provided with flow rate adjusting valves V ₁ and V ₂ , respectively. ₄ are connected to each other and each valve circuit P ₁ , P ₂ , P ₃ , P _{4 is connected.}
Is connected to the tank port circuit P from the middle of the solenoid valves SV ₁ and SV _2.
Connect ₅ .

A spool type control valve 24, which is branched from this part and is connected to the tank T via a flow rate adjusting valve 23, is connected to the bottom side valve circuits P ₂ and P ₄ of each hydraulic cylinder 8, and this control valve 24 And the top side valve circuit P _{1 of} the hydraulic cylinder 2,
A control hydraulic circuit 25 is formed by branching from a part of PP ₃ .

In the anti-vibration device of the stretcher configured as described above, when the patient lies on the ambulance C, the stretcher S lying down is first operated by operating the hydraulic cylinders 8, 8 to form the two arms 3, 4 assembled in a V-shape. It is rocked and the lifting frame 2 is stopped in a lowered state. At this time, the elevating frame position is below the surface of the stretcher bed.

An end portion of the elevating frame 2, more specifically, a slide-tilt type auxiliary guide rail Ra is provided at the rear end side of the vehicle for loading and unloading the stretcher when installed in the vehicle. When the stretcher is loaded and unloaded, the auxiliary guide rail Ra is provided. The stretcher S is simply pulled out from the storage state shown by the solid line in FIG. 2 and the tip of the auxiliary guide rail pulled out as shown by the dashed line in the figure is supported on the floor at the rear end of the vehicle, so that the stretcher S can be easily pulled out from the inclined guide rail Ra. After that, the guide rail R on the top surface of the elevating frame can be smoothly guided.

Then, the stretcher S is transferred to the predetermined position by inserting it into the ambulance C using the casters.

Then, when the stretcher S is pushed to a predetermined position, the horizontal rails at the front and rear portions of the stretcher are fitted into the fixed hook 14a by swinging the movable hook 14b. At this time, when the horizontal rail comes to the movable hook position, this horizontal calculation is performed by the movable hook 1.
4b, and the stretcher is locked on the lifting frame. Then, when the hydraulic pump is driven to swing the V-shaped arms 3 and 4 by driving the hydraulic cylinder 8 and the tip ends of the arms are raised, the lifting frame 2 pushes up the lower surface of the stretcher S. Then, the entire stretcher S is supported by the elevating frame. When the lifting frame rises to the fixed position, the swinging of the arms 3 and 4 is stopped. The ambulance C is run in this state. At this time, both control valves 24 are in the communicating position, and even if the ambulance C vibrates, the spring 7 and the hydraulic cylinder 8 (actually by the flow rate adjusting valve 23) provided on the arm cooperate. The impact force is absorbed during use.

When the lifting frame 2 is held at the lower limit position, there is an oil leak in the spool-type control valve 24, so that the lifting frame 2 may gradually rise due to the force of the compression spring 7.

In order to prevent this, the switch SW is operated so that the switch operates when the swing angle of the arms 3 and 4 rises to a predetermined angle.
₁ and SW ₂ are provided on the base or the frame.

When the switches SW ₁ and SW ₂ are actuated, the solenoid valve is opened, hydraulic oil is sent to the rod side of the hydraulic cylinder, and the lifting frame is lowered to a predetermined lower limit position.

In the above-mentioned embodiment, the arm arranged between the elevating frame and the base is V-shaped. As means for elevating the elevating frame, a parallel link type as shown in FIG. 6 is shown in FIG. X-type link type such as is adopted,
Both of the parallel link type and the X type link type are provided with a pair of compression springs and hydraulic cylinders and have the same operation as the V-shaped arm. Further, although the bed is explained as a stretcher in the above-mentioned embodiment, it may be a stretcher.

〔The invention's effect〕

According to the present invention, the compression spring and the hydraulic cylinder are provided as a pair between the intermediate portion of the arm and the base, and the base-side end portion of the compression spring is supported by the base via the movable bracket so that the spring of the compression spring can be supported. Since the pressure can be adjusted, a reliable cushioning effect can be obtained with a simple structure, and even if the lifting frame cannot be lowered by hydraulic pressure due to a hydraulic pump failure, etc. The lifting frame can be easily lowered from the floating state by adjusting.

Further, according to the present embodiment, the V of the V-shaped arm is set with the fulcrum of the two arms, which are assembled in a V-shape for raising and lowering the elevating frame on which the bed is placed and locked.
By changing the glyph angle, the minimum floor height for supporting the bed can be set lower than that of the conventional model, and the patient can be easily treated in the ambulance and the bed can be easily loaded and unloaded.

Further, according to the third aspect of the present invention, the guide rail is supported so that the head portion side (the traveling direction side of the vehicle) is bent lower than the foot portion side or the guide rail is supported by the elevating frame with an inclination angle. When braking, the stretcher on the lifting frame can be held horizontally or raised slightly forward,
It does not give discomfort or anxiety to injured patients.

Further, according to the fourth aspect of the invention, in order to compensate the oil leak of the spool type control valve, the swing angle of the arm is detected by the switch, and the hydraulic pump is operated by the compensation circuit. The letcher can be held in place.

[Brief description of drawings]

The drawings show an embodiment of the vibration isolator of the present invention. FIG. 1 is a plan view, FIG. 2 is a front view, FIG. 3 is a hydraulic circuit diagram, and FIG.
FIG. 6 is a front view of a lifting frame portion of another embodiment, FIG. 5 is an explanatory view of a state of being mounted in an ambulance, FIGS. 6 and 7 show different embodiments, and FIG. 6 is a parallel link. And FIG. 7 is a front view of an embodiment in which the lifting frame is supported by an X-shaped link. C is an ambulance, S is a stretcher, SV ₁ and SV ₂ are solenoid valves with check valves, SW ₁ and SW ₂ are switches, V is a vibration isolator, 1 base, 2 is an elevating frame, and 3 and 4 are arms. , 6
Is a shaft, 7 is a compression spring, 8 is a hydraulic cylinder, 10 is a movable bracket, 14a is a fixed hook, 14b is a movable hook,
15 is a wire or rod, 21 is a hydraulic pump, 24
Is a spool type control valve and 25 is a hydraulic circuit.

Claims (4)

[Claims] 1. A two-arm structure is provided on a base mounted on a vehicle, and a lower end of the arm is supported by a base and an upper end thereof is supported by a lifting frame. The elevator frame can be raised and lowered by rocking, and the lower part of the bed mounted in the ambulance is supported and locked by the elevator frame, and the elevator frame is raised and lowered between the middle part of each arm and the base. , A pair of hydraulic cylinders that also function as a compression spring and a damper for absorbing vibration are provided, and the base side end of the compression spring is supported by the base via a movable bracket so that the spring pressure of the compression spring is An anti-vibration device for beds in ambulances, which is adjustable. 2. The vibration damping device for a bed in an ambulance according to claim 1, wherein the two arms are combined in a V shape. 3. A guide roller is provided on the upper end of the arm, and the guide roller is supported by a guide rail provided on the elevating frame, a part or all of which is inclined with respect to the horizontal direction. The anti-vibration device for a bed in an ambulance according to claim 1 or 2, characterized in that it is held substantially horizontally. 4. A switch for detecting a swing angle of the arm is provided so as to compensate an oil leak of a spool type solenoid valve in a hydraulic circuit for operating a damper which also functions as the hydraulic cylinder, and a hydraulic pump is provided by an output of the switch. The vibration damping device for a bed in an ambulance according to claim 1, 2 or 3, wherein a stretcher on the elevating frame is always held at a lower limit position.