DE2210756A1 - Line training for motor vehicle braking systems with brake fluid recirculation - Google Patents

Description

Description of the patent application

of the FIAT Societa per Azioni, Turin / Italy

"Leadership training for motor vehicle braking systems with Brake fluid recirculation "

Priority: Italy from March 6, 1971

The invention relates to a line training for motor vehicle brake systems with brake fluid recirculation.

In hydraulic brake systems for motor vehicles it is known to use oil recirculation circuits, which volumetric circulation pumps and tanks, which act as heat exchangers serve, include. Effective cooling in such arrangements makes it possible to overcome the serious disadvantages a heating of the hydraulic brake fluid (the oil) in known brake systems are to be assigned, to be reduced, which ensures perfect operation even under harsh operating conditions.

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The effective cooling actually eliminates that Risk of the hydraulic fluid (oil) boiling, which normally occurs when braking is stopped or more generally, when a certain brake control, for example a non-slip or blocking brake control valve, is switched on is: boiling or boiling is caused by the sudden drop in pressure in the oil, combined with the high temperature, resulting from the burning process.

Against these considerable advantages, those with recirculating oil Braking systems are to be achieved, the disadvantage of a complicated circuit must be called, since it becomes necessary to each Brake actuation cylinder of the brake system with a feed line and to be provided with an oil recirculation or return line, resulting in higher construction costs and proportionally leads to greater vulnerability of the brake assembly.

According to the invention, leadership training is primarily intended be proposed, which avoids these disadvantages, with the feed and return lines to one in an effective manner single line formation can be combined with suitable connections.

To this end, the invention is based on a line training for a motor vehicle brake system with brake fluid recirculation and is characterized by the fact that the pipeline formation an inner conduit forming an inner channel for supplying brake fluid to a brake actuation cylinder, as well as a has outer line which coaxially surrounds the inner line and with this an outer channel annular Cross-section for the return flow of the recirculating brake fluid, with the line formation at one end cooperates with a three-way connector to the inner and External channels to the respective feed and return lines of the

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Connect reζirculation systems.

The invention will now be explained in more detail with reference to the accompanying drawing, in which

Fig. 1 is a hydraulic circuit diagram for an oil circulation system is shown in which the line training according to the preferred embodiment according to the Invention is applicable;

Fi ;;. Figure 2 is a partially sectioned view of a piece of tubing according to one embodiment of the invention and the connections that interact with it; and

Fig. 3 is a longitudinal section on a larger scale than Fig. a part of a line training according to Fig. attached connector.

Fig. 1 shows an oil circulation brake system with a V'ärneaustauschbehälter 1, from which a volumetric pump 2 sucks brake fluid (Cl) and delivers the 'M via a line 3 to individual ^ re ^ sbetäti ^ erzylinuer 4 of the vehicle brakes, not shown, only one of the cylinders 4 being shown for reasons of clarity. The circulating oil absorbs the heat generated in the cylinders 4 and is then recirculated into the container 1 via a return line 5 and a valve 6. The valve 6 is normally open and can be actuated by a brake pedal 7. If the pedal 7 is pressed down ge, the valve 6 ^ is closed, whereby the recirculating oil flow is shut off and an increase in oil pressure before the. Valve 6, that is, caused in the brake actuator cylinders, so that braking takes place.

In an oil-circulating brake system of the usual type it is necessary that for each fuel cylinder 4 a

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^ feed line 3 and a Glrückführleitung 5 available are. The need to provide two ″ lines 3, 5 for each actuator 4 brings practical disadvantages to the above Kind of with itself.

These disadvantages are avoided by using line formations can be provided for connection to each brake cylinder 4 according to the invention.

The line formation comprises an outer tube or an outer hose 8 made of flexible, for example elastomeric material. The hose 8 is connected at one end to a connection piece 9 which is connected to the cylinder 4; At its other end, the hose 8 is connected to the oil circulation path via a three-way connector 10 rr. The outer hose 8 is provided with an inner hose 11 of smaller diameter, which forms an inner channel 12 of circular cross-section and an outer channel 13 of circular cross-section, the latter being delimited by the inner surface of hose 8 and the outer surface of hose 11. The inner channel 12 communicates with the cylinder 4 at one end in connection unc ¹ serves to supply oil to the cylinder 4 under pressure.

According to the illustrated embodiment, the end of the Inner hose 11 in the cylinder 4 in a position substantially coaxial with the outer hose 8 via a suitable manner Openings provided spacer 14 held, which between a threaded end Ca of the connecting piece 9 and a countersunk seat is arranged at the inner end of a screw socket in the wall of the cylinder 4, in which the threaded end 9a of the connecting piece 9 engages. The spacer 14 is not essential, however, as a coaxial Positioning of the inner tube 11 within the outer tube 8 in practice by the action of the circulating Oil is ensured.

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The outer channel 13 is provided with openings üstanzstück 14 connected to an opening 14a, the is open to the inside of the cylinder 4. The Anschlussstutzeri 9 has a tubular extension 9b over which one end of the outer tube G fits; the wall of the hose or tube 8 is placed between this extension piece 9b and an outer tubular sleeve 3c which is integral with the extension piece 9 is formed, held. The hose 8 is firmly clamped by the action of a clamping element, for example a clip 15 which encloses the sleeve 9c. Other means of sealing and restraining the hose 8 can be used; for example, the hose be introduced directly into the v / andung of the cylinder 4.

The other end of the outer hose 8 is attached to a socket or an extension piece 16, which is in the three-way connector is screwed in. An outer socket or extension is also screwed into the connector 10. The end piece has an attachment onto which the inner tube 11 fits and is held by a clip 18. Finally, the connector has a cylindrical cavity 19 into which an opening 20 communicating with the annular channel 13 opens. A Branch pipe or a branch line 21 is also available communicates with the cavity 19 and has an external screw thread 22.

The oil feed line 3 is in operation on the outer sleeve or attached outer extension piece 17, while the Rüclcführleitung against the screw external thread 22 on the branch pipe of the connector 10 is attached. The oil supplied to the cylinder 4 thus passes through the bore of the outer extension piece 17 and through the inner channel 12 to the cylinder 4 and effectively cools the latter. The oil exits from cylinder 4 through the spacer 14 provided with openings, the outer channel 13 of circular cross-section, the chamber 19 and the branch pipe 21. From the branch pipe 21 flows

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the oil through the valve 6 (Fig. 1) and then back to the tank 1, where the heat from the cylinder 4 is given off.

In practice, the three-way connector 10 becomes integral with the chassis of the motor vehicle connected during the line training forms a flexible connection to the cylinder 4 and thus a relative movement between the wheel and the chassis due to the vehicle suspension makes possible.

It goes without saying that construction details and practical forms of implementation of the invention are in the broadest scope to vary with respect to the described and illustrated embodiments.

- patent claims -

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Claims (5)

- 7 claims 1.1 Leadership training for a motor vehicle braking system t brake fluid recirculation, characterized by an inner hose or an inner tube (11), which has a Inner channel (12) for supplying the brake fluid to a Forms brake actuation cylinder (4); and through an outer tube or an outer tube (S) which coaxially surrounds the inner tube (11) and thereby forms an outer channel (13) in the shape of a circular ring Cross-section for the return flow of the recirculating brake fluid, with the line formation on one end with a three-way connector (10) for connecting the Inner and outer channels (12, 15) cooperate in each case on supply and return lines (3, 5) of the recirculation system. 2.) Leituii ^ sausbildung according to claim 1, characterized in that the outer hose (S) and the inner hose (11) flexible. aterial, in particular elastomeric ^ material, is made. 3.) Leitun <; sausbildung according to claim 1 or 2, characterized through a connection piece (9) at the other end of the line formation for connection to the cylinder (4), this connecting piece (9) having a tubular extension (9b), through which the inner tube (11) is guided into the cylinder, the inner tube (11) with the tubular Extension (9b) forms an annular passage which is in communication with the cylinder (4) and with the outer channel (13); and where this outer hose (8) engages over the tubular extension piece (9b) and then through a connecting piece (9) attached sleeve (9c) and a clip surrounding the sleeve (15) is held. 209838/0864 221075R 4.) line training according to claim 3, characterized in that the inner tube (11) in a substantially coaxial position with respect to the outer hose (8) by an annular one provided with openings and carried through the connecting piece (9) üistanzstück (14) is held. 5.) line training according to one of the preceding claims, characterized in that the three-way connector (10) a the end of the outer tube (G) forming an inner sleeve (16) with a continuous channel for the inner tube (11); that an outer socket or an outer connection piece (17) forms the end of aes inner hose (11); and that a cylindrical cavity (19) within the connector communicates with a branch pipe (21), the outer connection piece (17) and the branch pipe or branch hose (21) for connection to the brake fluid feed line (3) and the return line (5) of the recirculation system are designed. PATENl ANWALT !: ORMMO. H. FINCKE, DIPL-InS. DIPL-ING. S. ST AEGEK 2 U 3 b i 8 / U M b U