JP2631889B2 - Rapid tire decompression device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention deals with an aircraft accident such as an ambulance, a fire engine, a rescue vehicle, etc., which is sometimes deployed at an airport or occurs near or at an airport, and rescues victims. The invention relates to a rapid tire decompression device for emergency vehicles used to perform.

BACKGROUND OF THE INVENTION Emergency vehicles as described above must have the ability to travel on paved runways, roads, etc. as fast as possible, and have considerable apprehension in loose areas such as mud, sand, snowfall, etc. It is necessary to have the ability to run at speed.

It is well known that emergency vehicle traction in loose areas can be significantly improved by reducing tire inflation pressure and increasing tire footprint. Devices for increasing or decreasing the main tires of vehicles are also known, especially for military vehicles, US Pat. No. 4,690,331,
Nos. 2,634,781 and 3,361,180. Such devices are known as primary tire intensifiers (CTIS) and allow a driver to remotely, manually and / or automatically change the pressure of one or more of the vehicle's tires and / or Can be maintained. A source of pressurized fluid (usually air from a vehicle's air brake compressor and / or compressed gas reservoir) is used as the pressurization source. Such devices have been fully satisfactory for vehicles such as military vehicles using CTIS for changing conditions in loose areas.

U.S. Pat. No. 3,361,180 discloses a tire decompression device for a military aircraft. The device includes an electromagnetically actuated tire valve to take off the aircraft with the tires fully inflated and to depressurize the tires during flight to a predetermined low pressure to land in unmaintained fields or sandy wilderness. The electromagnetically actuated tire valve is used to excite the tire valve.
A set of brushes and commutator rings are required.

(Problems to be Solved by the Invention) In the former of the above conventional example, a pressure intensifier is required in addition to the tire pressure reducing device, and the pressure increasing or depressurizing of the tire is relatively slow, and the assembly and maintenance are relatively expensive. For this reason, the above-mentioned emergency vehicle was not satisfactory.

Similarly, in the latter case (U.S. Pat. No. 3,361,180), it takes time to depressurize the tire, and it is relatively expensive and maintenance is difficult.

The present invention readily and quickly depressurizes all of the tires of an emergency vehicle while the emergency vehicle approaches the edge of a hard surface road or runway, and simultaneously or nearly simultaneously when the emergency vehicle reaches a loose area. It is an object of the present invention to provide a tire decompression device that can make a vehicle reach an accident site as quickly as possible by increasing a contact area of a tire.

Another object of the present invention is to provide an emergency vehicle tire decompression device in which the minimum decompression pressure of the tire is obtained by controlling the decompression time of the tire.

(Means for Solving the Problems) The present invention has the following configuration to achieve the above object.

An emergency vehicle rapid tire decompression device, comprising: a plurality of wheels each having a pressurized tire; and a normally closed tire that is mounted on each wheel and exhausts pressurized air of the tire to the atmosphere when opened. An air-operated two-position wheel valve, and an air circuit for operating the wheel valve, the air circuit connecting a solenoid valve connecting the air circuit to a pressurized air source of the vehicle and each wheel valve. An air circuit, wherein the solenoid valve is mounted on the vehicle, and is energized by a manual switch that excites the solenoid valve to depressurize the tire by opening the wheel valve by pressurizing the air circuit during operation; Further, while the tire is required to be depressurized to a predetermined low pressure, the solenoid is energized to release the wheel valve. Open and a electric control circuit and the tires for controlling the time.

(Operation) Since the present invention has the above-described configuration, when the driver operates a manual switch when an emergency vehicle approaches a loose area, the solenoid valve 88 is opened, and pressurized air from the air source 84 is supplied to the air circuit. Press. Due to this pressurization, the wheel valve 48 is opened, the air of the tire is exhausted, and the contact area of the tire increases.

(Effect of the Invention) As described above, when an emergency vehicle approaches a loose area,
When the switch is operated, all the tires are depressurized in a predetermined time, and as a result, the contact area of the tires becomes larger, so that the emergency vehicle can travel in a loose area, and the traction force increases, and the emergency vehicle is moved to an accident site. Can be reached quickly.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings. According to the present invention, all tires 12 of the emergency vehicle as described above
Can be evacuated almost simultaneously and quickly by the air bleeding device 10 shown in FIG. Each of the inflated tires 12 is mounted on a tire rim 14. The tire rim 14
The outer end of the axle housing 18 is fixed to the wheel assembly 16 rotatably indicated by means of a bearing 20. An annular sleeve 24 is press-fitted to the axle at a position inside the bearing 20. The wheel hub is formed with an annular flange 26 in the form of a sleeve extending inwardly around the sleeve 24 in a telescopic manner. A pair of rotary seals 28, 30 extend radially between the outer periphery of the sleeve 24 and the inner periphery of the sleeve type flange 26 to define a chamber 32 between the inner and outer periphery. This arrangement is disclosed in U.S. Pat. No. 4,434,834, assigned to the assignee of the present invention.
The details are shown in the specification. The sleeve 24 has an inlet 34 opening to the chamber 32 and a passage 36 formed therein. The sleeve type flange 26 has a passage extending substantially radially from the sealed chamber 32 to the outer surface of the flange 26.
38 are formed. The flange portion 42 extending in the radial direction of the wheel hub 16 has a single passage for passing the pressure tube 44.
Forty are formed.

The pressure pipe 44 is a tire control valve mounted on the wheel hub 16
It is connected to an entrance 46 of 48. The valve 48 has a port 50 connected to the inner chamber 54 of the tire 12 by a pressure tube 52. A manual air check valve 56 is connected directly to the interior chamber 54 via the pressure tube 52 or the rim 14.

As shown in FIG. 2, the wheel valve 48 is normally closed by air pressure. The valve 48 has three ports: a port 50 connected to the inner chamber 54 by a pressure tube 52, and a port connected to the sealed chamber 32.
Port 58 connected to 46 and exhaust pipe 60 opening to the atmosphere
Are formed. Valve 48 includes a tubular body 62 sealed by end plugs 64,65. Annular valve seat
68 is formed between the ports 50,58. Valve seat 72
Is biased by the compression spring 74 and is airtightly engaged with the seat 68. The plug 64 includes a projection 76, a portion of which forms a cavity 78 for extending into a blind hole in the valve member 70 and retaining a spring 74. Thus, valve 48 is normally held in the closed position to prevent air from escaping from pressure pipe 52 to exhaust pipe 60.

Valve 48 is opened by pressurized air flowing into port 46. That is, the pressurized air flowing into port 46
Activate 80 to move piston 80 and projection 82 to valve member 70
Move in the direction. As a result, the valve seat 72 of the valve member 70 separates from the valve seat 68 against the urging force of the spring 74. The valve seats 72 and 68 are therefore not hermetic and they are far enough apart to allow a free flow of air from the tire 12 to the exhaust pipe 60 for rapid exhaust. Although the structure of the valve 48 has been described in some detail as described above, a pneumatic valve having a different function may be used as long as it has the same function.

Each of the emergency vehicle wheel assemblies 16 is a wheel valve supplied with working pressurized air from a common air source 84
It has 48. As the air source 84, a pressurized air reservoir supplied by a compressor is typically used.

The air source 84 is connected by a pipe 90 to a two closed position exhaust valve 88. The outlet 92 of the valve 88 is connected to a manifold 94 and usually to a port 100 of the exhaust pipe 102.
A plurality of tubes 104 enter the manifold 94, the airtight chamber 3
2, connected to each of the pipe 44 and the wheel valve 48 of each wheel of the vehicle.

A closed exhaust valve 88 permits air flow between the inlet 86 and the outlet 92 and a first or neutral position that blocks air flow between the inlet 86 and the outlet 92 as shown in FIG. Second
Position or open position. The valve 88 is an electromagnetically actuated, preferably a conventional solenoid controlled valve which is spring biased to a neutral position as shown in FIG. In the neutral closed position, the outlet 100 is open and exhausts air from the air circuit to the manifold 94 and each wheel valve 48 to the exhaust system 102.

The solenoid 106 of the valve 88 is connected to a "tire depressurizing" push button switch 108 mounted on a control panel 110 provided in the cab of the vehicle. An on / off switch 112 having a screw operation adjusting means 116 and a timer 114 are mounted on the control panel 110 and connected to a battery 118. The timer adjusting means 116 initially determines that the timer clock inside it has the normal working pressure acting on the road, e.g.
It is manually adjusted to operate for a predetermined time required to reduce the pressure of the tire 12 from 60 psi to low pressures used in loose areas such as mud, sand, snowfall, eg, 20 psi. The time at which the timer clock runs depends on the initial tire pressure, tire dimensions, and the dimensions of the passages and ports in the tubes 52 and wheel valves 48 mounted on each wheel 16. Normally, timer adjustment means 116
Timer 114 is manually set to operate for a few seconds to 30 seconds, corresponding to the time required to reduce tire pressure from normal operating pressure to the lowest pressure that is most effective in areas where it has been relaxed. You.

Suppose an emergency vehicle equipped with a tire decompression device according to the present invention is deployed at an airport and an airplane crash occurred in a loose area some distance from the end of the runway. Emergency vehicles can run at maximum speed along the runway with tires inflated at normal pressure. When the emergency vehicle approaches the end of the runway, the driver turns on the switch 112. When the emergency vehicle approaches the loose area, the driver presses the pressure-reducing push button 108 to excite the solenoid 106 of the valve 88 and start the timer 114. The solenoid 106 operates the valve 88 to open the inlet 86 and the outlet 92, and allows pressurized air from the air source 84 to flow into the manifold 94 and the air circuit to open the normally closed wheel valve 48. At the same time, the outlet port 100 of the solenoid valve 88 is closed. Wheel valve 4
8 are all kept open as long as the air circuit connected to them is pressurized. After the timer 114 has operated for a predetermined time, the solenoid 106 of the solenoid valve is demagnetized, and the valve 88 assumes the neutral position shown in FIG. Wheel valve
The air circuit connected to 48 is depressurized and each of the wheel valves is closed as shown in FIG. At this point, the pressure on each tire has been reduced to a minimum pressure for traveling in the relaxed area. This decompression occurs at or near the same time as the emergency vehicle reaches the loose area.

[Brief description of the drawings]

 FIG. 1 is a schematic view of a rapid tire pressure reducing device according to the present invention, and FIG. 2 is a sectional view of a normally closed wheel valve. 12 Tires 48 Wheel valves 88 Solenoid valves 114 Timer

Continuation of front page (56) References JP-A-53-7111 (JP, A) JP-A-62-6804 (JP, A) JP-A-63-222909 (JP, A) JP-A-61-169304 (JP) , A) Japanese Utility Model Showa 56-88179 (JP, U) Japanese Utility Model Showa 57-97707 (JP, U) Japanese Utility Model Showa 50-124375 (JP, U) Japanese Utility Model Showa 62-170306 (JP, U) 46-5169 (JP, B1) Japanese Patent Publication No. 44-5922 (JP, B1) Japanese Patent Publication No. 4-36407 (JP, B2) Japanese Utility Model No. 44-16003 (JP, Y1) Japanese Patent Publication No. 35-18404 (JP, B1) Y1) Jiko Hei 3-26965 (JP, Y2) Jiko Hei 4-51045 (JP, Y2) Jiko Sho 60-7924 (JP, Y2)

Claims (4)

(57) [Claims] 1. A rapid tire decompression device for an emergency vehicle, comprising: a plurality of wheels each provided with a pressurized tire; and a pressurized air of the tire being released to the atmosphere when mounted on each wheel and opened. A normally closed air-operated two-position wheel valve for exhausting, and an air circuit for operating the wheel valve, which connects a solenoid valve connecting the air circuit to a pressurized air source of the vehicle and each wheel valve. A pneumatic circuit including an air conduit, wherein the solenoid valve is mounted on the vehicle, and when activated, a manual actuation of the solenoid valve to depressurize the tire by pressurizing the air circuit and opening the wheel valve. The solenoid is energized by a switch, and while the tire is required to be depressurized to a predetermined low pressure, the solenoid is excited to excite the tire. Rapid tire deflation device which comprises an electric control circuit and the tires for controlling the time of opening the Eel valve. 2. The apparatus according to claim 1, wherein said control circuit holds said solenoid valve in the open position for a predetermined time until said tire is reduced to a minimum pressure. 3. The apparatus of claim 1, wherein said manual switch excites said tire and solenoid valve when activated. 4. The apparatus according to claim 1, wherein the tire is manually adjusted to increase or decrease the time during which the solenoid valve is energized, thereby controlling the pressure reduction of the tire.