DE102007036201B4 - Free-wheeling valve for vehicles with tire pressure control - Google Patents

Abstract

Valve (5) for pressure measurement and for pumping up and sucking off a volume (4), consisting of a body (20) closed by a cover (21), a control chamber (23) in connection with a suction station (7), an outflow chamber (24) ) connected to the outside through an air outlet hole (25), a pressure chamber (26) connected to the volume (4) through a bore (27), characterized in that this pressure chamber (26) contains a movable piston (22) which does not friction between cover (21) and body (20) and seals both parts, this piston (22) being hermetically connected to the cover (21), and where this piston (22) on the one hand with the body (20) the control chamber (23 ) and delimits the pressure chamber (26), on the other hand delimits the outflow chamber (24) with the cover (21), said piston (22) having means to enable a flow connection between the various chambers (23, 24, 26).

Description

The technical field of the following invention comprises the regulation systems and the pressure control of a volume, e.g. B. a vehicle tire.

In connection with the above-mentioned area of application, it has already been proposed to use a pneumatic valve for tire inflation and for releasing air from a conventional tire. The principle of tire inflation and deflation from a vehicle tire with the help of remote-controlled valves has already been mentioned in the patents FR 2 616 194 A1 , FR 2 667 826 A1 and FR 2 731 655 A1 set out.

The use of these valves is based on the following technology: Flaps are used which, in a first position, allow compressed air to pass into a room. In a second flap position, the air is discharged from the room contents to the outside and a third so-called rest position ensures that the pneumatic circuit is closed.

In order for this to work, the flap is generally exposed to a higher pressure than that in the volume in order to enable the supply of compressed air to this volume. This pressure is significantly lower than the pressure in the volume, even negative. This allows air to be vented from the volume to the outside.

These systems for extracting the volume of the room with low, positive or negative pressure have a decisive disadvantage: the flaps used are blocked because of the diaphragm diameter and other necessary devices.

Another main disadvantage of systems that have a low pressure, which, however, is far below the targeted minimum pressure for evacuating the volume, is the risk of instability after the evacuation process.

Systems that use negative pressure to evacuate the volume also have the serious deficiency that it is difficult to achieve this negative pressure in a vehicle. In addition, the tightness of the pipe joint that is required to supply the flap with this negative pressure from the air source fails.

It is also very important with these developments that this flap works as reliably as possible so that it can react immediately to "pneumatic commands".

If one now wants to achieve the long-term reliability of a pneumatic component that is exposed to polluted air, as is the case with a tire, then one must understandably forego any device that contains moving components and are exposed to friction, or such that prevent fluids or contaminants from being removed quickly.

Any friction would result in hysteresis effects that the control system would be difficult to cope with. Much more serious would be any blockages when foreign bodies penetrate between the rubbing parts.

From the U.S. 4,744,399 A a valve is known which comprises a body and a lid in which a control chamber, a pressure chamber and an outflow chamber are provided. Furthermore, a piston is provided which is mounted in the valve via piston guides.

In the EP 0 511 135 A1 and the US 2004/0103939 A1 a valve is shown in each case, which has a cavity in which a piston is movably mounted via a membrane in such a way that the membrane divides the cavity into a control chamber and an outflow chamber.

The object of this invention is to eliminate all these problems by the introduction of a pneumatic component which enables rapid evacuation of the volume while driving, exerting a positive pressure on the component which is substantially higher than that for the same Volume targeted maximum pressure. All of the previously explained reliability and tightness criteria are met, i.e. the component is small in size, does not cause friction and does not hinder the removal of foreign bodies that are in the tire. Conventional operations such as tire inflation, pressure measurement or slow deflation can be performed as usual.

This invention is therefore a valve for pumping up and sucking off the volume of the room and measuring its pressure. This volume consists of a base closed with a cover and is divided into the following chambers: A control chamber in connection with a suction station; an outflow chamber securing the connection to the outside through an air vent hole; a pressure chamber connected to the volume through a bore. This pressure chamber contains a movable piston that does not cause any friction between the cover and the body and seals both parts. This piston is hermetically connected to the lid The volume of the space separates the various elements through its course and connects the various chambers: on the one hand the housing with the control and pressure chamber, on the other hand the cover with the control and outflow chamber.

The following is a description of the main features of the piston. This is hermetically connected to the lid by a metal bellows, which in turn is attached to the lid.

Due to the traction of the bellows and with the help of a sealing material, the piston remains constantly in contact with a base attached to the cover. A hole in the piston leads to a shutter.

This flap consists of a ball that is attached to a base by a retention system on the piston.

The restraint system in turn consists of deformable lips which are supported on a cover of the ball.

In relation to the piston, the restraint system is held in position by a ring.

In order to allow the volume to be inflated, the flap ball remains in contact with the ground because of the tire inflation pressure.

In order to enable the volume to be inflated quickly, the flap and the piston remain in contact with the ground.

The main advantage of this invention is that the development of vehicle tires has a simplified structure, which makes it possible to monitor the tire inflation pressure with the aid of all integrated elements and to see the exact status through the small size of the free-wheeling valve.

Another important advantage of this invention is the fact that no negative pressure is necessary for the valve control. This significantly facilitates the operation of the control device and the sealing rings, which are part of the connection between the tire rotating area and the immovable system area.

• - Die zeigt den schematischen Schnitt eines Fahrzeugreifens gemäß der vorliegenden Erfindung im Zusammenhang mit einer Aufpumpvorrichtung;
• - die zeigt einen Schnitt einer Ausführungsform des Freilaufventils in seinem Ruhezustand;
• - Die 3a und 3b zeigen zwei verschiedene Zustände des Freilaufventils während dem Betrieb.

For informational purposes, further properties and advantages are described in the following drawing.

• - The shows the schematic section of a vehicle tire according to the present invention in connection with an inflation device;
• - the shows a section of an embodiment of the free-wheeling valve in its rest state;
• - The 3a and 3b show two different states of the free-wheeling valve during operation.

In the you can see the tire 1 of a vehicle, not shown, consisting of the rims 2 on which an external shell 3rd is mounted. This shell represents the volume of the room 4th represents, ie a volume that can contain an air pressure. The rims 2 contains a free-wheeling valve 5 that connects the following elements: on the one hand, the line 6th with the volume 4th and on the other hand with the control device 7th through the line 8th connected by a pipe joint 9 and a connecting chamber 18th .

The control device 7th is of a well-known design and usually contains a suction station 10 , a control unit 11 along with a keyboard 12th and an electro-pneumatic assembly 13th .

An advantageous addition to the control device 7th consists of the following elements: One in the volume 4th integrated pressure and temperature detector 15th , one in the control unit 11 integrated receiver 14th as well as a pressure sensor 16 and one in the electro-pneumatic assembly 13th integrated discharge device 17th . The role of these last elements is described below.

In the 2 becomes the valve 5 shown according to the invention. It consists of a through a lid 21 closed body 20th and contains a piston 22nd . On the cover side, there are different chambers of this piston 22nd delimited: by the connecting chamber 18th , the pipe joint 9 and the line 8th , leads a control chamber 23 to the control device 7th ( 1 ); an outflow chamber 24 is through an air vent 25th connected to the outside world. On the body side: one with the volume 4th through a hole 27 connected pressure chamber 26th , with the line 6th of the rim connected ( 1 ). The vent hole 25th is located in the lid 21 and in the body 20th ; the hole 27 is located in the body as shown in the figure 20th .

The piston 22nd is hermetic with the lid 21 by a metal bellows 28 connected to the one hand by a ring 29 on the lid and on the other hand on the piston 22nd through a washer 30th is attached.

Along with the valve 5 generates the control device 7th three different pressure levels in the control chamber 23 of the valve according to the invention, through the conduit 8th , the pipe joint 9 and the connecting chamber 18th . The first The pressure level corresponds to the atmospheric pressure, the second corresponds to either the tire inflation pressure, the pressure according to the measured value or the pressure by slowly releasing air and the third corresponds to the pressure for rapid deflation.

The control chamber 23 is therefore with the pneumatic control device 7th in connection and ensures a variable pressure supply that is greater than that for the volume of the room 4th targeted maximum pressure, or a pressure that is significantly greater than the same maximum pressure in the line 8th , Pipe joint 9 and connecting chamber 18th .

The shut-off device of the valve is thus on the one hand by the acting force of the metal bellows 28 controlled, which connects the closure with the valve cover and on the other hand by the in the volume 4th prevailing pressure. This ensures double security to close any air passage as long as the valve does not respond to a "pneumatic command".

The piston 22nd contains a central hole 37 with built-in flap 33 and contains an inexpensive frustoconical or hemispherical outer part 34 . This part contains a sealing mechanism 35 that is on the pedestal 36 of the lid 21 supports under the influence of the constantly acting traction of the metal bellows 28 and additionally by the existing pressure in the pressure chamber 26th .

In one of these possible developments the flap has 33 the shape of one in the hole 37 inserted ball 39 . This flap contains on the side of the control chamber 23 a pedestal 38 and serves this ball 39 as a tight support. On the side of the body, the valve contains one of the ball 39 removable lip device 40 with a ring 41 who got the ball 39 controls when using the contact piece 42 of the valve body comes into contact.

The opening and height of the ring 41 are planned in such a way that an escape of the ball 39 is prevented. The height of the ring 41 was also chosen to avoid any contact between the ring and the subsurface of the body 20th to avoid. Thus the loosening of the ball is 39 secured in any case.

The flap 33 thus directs the ball 39 to two different positions, divided by the removable lip device 40 when the ball is on the base 38 overturned from its rest position to its second position and then moved with the contact piece 42 of the valve body comes into contact.

The piston central bore 37 can be closed on the cover side with the help of a plate 32 drawn by a spring 31 with the washer 30th connected is. This record 32 is subjected to the pressure generated by the control device 7th comes before this hit the ball 39 affects. In case of very high pressure from the facility 7th becomes the plate 32 directly exposed to this high pressure, the spring 31 is compressed and drives the piston 22nd at; this then drives the ball 39 towards the contact piece 42 of body 20th . The feather 31 is calibrated so that it can withstand low pressure. This low pressure will merely cause the ball to move 39 Direction of contact piece 42 of body 20th cause; The piston 22nd remains in its original position.

2 shows the free-wheeling valve in the normally closed position, ie the volume 4th was inflated ( 1 ) and the pressure it exerts, e.g. B. 3 bar, ensures that the ball 39 in their pedestal 38 with the hole 37 remains in contact and that the piston 22nd in the lid 21 with its base 34 stay in touch.

3a shows the ball 39 in their position when inflating, during pneumatic pressure measurement or when slowly releasing air from the room 4th .

Starting from the control chamber 23 , from the control device 7th out ( 1 ), a gas pressure is supplied for this purpose, the z. B. is 1 bar greater than the targeted maximum pressure for the tire. This pressure causes the ball to lift off 39 from its base 38 and their movement to a second position, where they then meet the contact piece 42 of the valve body 20th comes in contact after having the lip 40 removed and, led by ring 41 , her last movement begins. In order to pump up the volume, the compressed air supply runs from the control device 7th to the volume 4th ( 1 ). The course is as follows: Control Chamber 23 , Drilling 37 , Ring 41 and pressure chamber 26th ; The hole 27 and the line 6th of the rim ( 1 ) ensure that the volume of the room is inflated 4th .

If the air supply is interrupted after this tire inflation pressure, the ball remains 39 in their position, as in 3a shown. The pressure is then equalized between the control device 7th and the volume 4th ( 1 ). The pressure measurement of the volume 4th can now benefit from the sensor 16 be made in the electro-pneumatic assembly 13th is integrated ( 1 ), or through the in the volume 4th integrated sensor 15th in connection with the control unit 11 and the recipient 14th .

A slow release of air from the contents of the room 4th is also possible, through the outflow device 17th ( 1 ). This allows a very controlled, step-by-step air release through the electropneumatic assembly 13th ( 1 ) with their corresponding connections to the volume 4th . This air release can advantageously be controlled by a pressure reading from the sensor 16 ( 1 ), which is in the electro-pneumatic assembly 13th is integrated, or through the in the room 4th integrated sensor 15th ( 1 ), in connection with the control unit 11 and the recipient 14th ( 1 ). The ball is in this structure 39 still in its open position through the lip 40 . Their resistance to the passage of the ball is greater than the force acting on the ball, a force that results from the small pressure difference between the volume 4th and the electropneumatic block goes out.

It is worth noting here that the ring 41 closing off the air supply and clamping the ball 39 prevented.

3a shows another position of the piston 22nd and the ball 39 with rapid deflation of the volume 4th ( 1 ). Starting from the control chamber 23 , for this purpose, a strong pressure is applied to the connection chamber 18th fed ( 1 ), the z. B. 2 times larger than that for the volume 4th targeted maximum pressure. This pressure sets the piston 22nd moving. Led by the bellows 28 this piston becomes stable on the contact piece 42 of the valve body 20th overturned. This is done with the help of the ball 39 , which presses the piston onto its base, resulting in a complete tightness between the high pressure connecting chamber 18th ( 1 ) and the pressure chamber 26th guaranteed. The movement of the piston 22nd as well as its lifting from its base 36 allows air to circulate freely between the contents of the room 4th and the outflow chamber 24 , whereby the following elements are involved: The rim line 6th ( 1 ); the hole 27 of the valve block 20th ; the pressure chamber 26th .

A quick air release of the room contents can be found to the outside through the air vent hole 25th instead (see arrows) by moving the air through the volume 4th flows ( 1 ), through the line 27 to the outflow chamber 24 .

It goes without saying that this system is applied to all vehicle tires; for the sake of simplicity, only one tire is shown here.

According to the invention, a control system is added to the previously described tire to control the pressure in the volume 4th to control and this automatically according to certain criteria, such as. B. the transported load or the state of the terrain to change.

Obviously, such a possibility is welcomed by the users. Depending on whether the vehicle is fully loaded, half loaded or empty, the vehicle structure is not equally stressed. The same applies if the vehicle is on the road on cut terrain, on sandy ground, on a road or on a motorway. The control of the tire inflation pressure makes it possible to reduce such stresses and ensures that they comply with the mobility and safety criteria. It also contributes to the normal service life of the vehicle. Precise intervention in the tire inflation pressure for each individual vehicle tire even makes it possible to optimize mobility and safety conditions.

On the other hand, it is important to know the exact condition of the vehicle tires at all times, especially in cases of blown tires or irreparable damage.

The following operations can be carried out with this assembly: inflating or deflating the tire from wheel 1 or from a group of tires, as the case may be; an automatic monitoring of individual or a group of tires based on a constant temperature and pressure display; an automatic pressure adjustment of the tire as a result of an instruction; Capturing and locating a space that is open to the outside; equalizing the same opening; A separation of the tire from the rest of the system if compensation is not possible; The transmission of information about overspeed and a corresponding pressure correction.

Claims (10)

Valve (5) for pressure measurement and for pumping up and sucking off a volume (4), consisting of a body (20) closed by a cover (21), a control chamber (23) in connection with a suction station (7), an outflow chamber (24) ) connected to the outside through an air vent hole (25), a pressure chamber (26) connected to the volume (4) through a bore (27), characterized in that this pressure chamber (26) contains a movable piston (22) which does not friction between cover (21) and body (20) and seals both parts, this piston (22) being hermetically connected to the cover (21), and where this piston (22) on the one hand with the body (20) the control chamber (23 ) and delimits the pressure chamber (26), on the other hand delimits the outflow chamber (24) with the cover (21), said piston (22) having means to enable a flow connection between the various chambers (23, 24, 26). Valve (5) for pressure measurement and for pumping up and sucking off a volume (4) according to Claim 1 , wherein the piston (22) hermetically with the Cover (21) is connected by a metal bellows (28), which in turn is attached to the cover (21). Valve (5) for pressure measurement and for pumping up and sucking off a volume (4) according to Claim 2 wherein the piston (22) remains constantly in contact with a base (36) mounted on the lid (21), under the influence of the constant traction of the bellows (28) with the aid of a sealing material (35). Valve (5) for pressure measurement and for pumping up and sucking off a volume (4) according to any Claim 1 to 3rd a bore (37) leading from the piston (22) to a position with a closure flap (33). Valve (5) for pressure measurement and for pumping up and sucking off a volume (4) according to Claim 4 , wherein this flap (33) consists of a ball (39) which is attached in the bore (37) to a base (38) by a retaining system (40) on the piston (22). Valve (5) for pressure measurement and for pumping up and sucking off a volume (4) according to Claim 5 wherein the retention system (40) consists of a deformable lip supported on a cover of the ball (39). Valve (5) for pressure measurement and for pumping up and sucking off a volume (4) according to Claim 6 wherein the restraint system (40) is connected to the piston by a ring (41). Valve (5) for pressure measurement and for pumping up and sucking off a volume (4) according to any Claim 4 to 7th wherein the valve contains a closing flap (32) for the piston bore (37) which is subjected to the action of the return spring (31). Valve (5) for pressure measurement and for pumping up and sucking off a volume (4) according to any Claim 4 to 7th wherein, in order to allow the volume (4) to be inflated, the flap ball (33, 39) remains in contact with the ground (20) because of the tire inflation pressure. Valve (5) for pressure measurement and for pumping up and sucking off a volume (4) according to any Claim 4 to 7th , wherein, in order to allow a quick release of air from the room contents (4), the closure flap (33) and the piston (22) remain in contact with the substrate (20).

Images