Hydraulic block of an electrohydraulic power-assisted brake

A hydraulic block, the upper side of which is provided with a brake-fluid reservoir which is fixed in place on the front surface and on the rear surface of the block by fastening apparatus/device (arrangement). The front fastening apparatus/device (arrangement) is formed by a tab that projects from the underside of the reservoir, this tab being screwed to the front surface of the block. The rear fastening apparatus/device (arrangement) is made up of a tab, which projects from the rear side of the reservoir and is formed by a hook that is supported by a carrier that is fastened to the rear side of the hydraulic block and forms a support for the tab, as well as a clamp, which connects the tab to the hook.

FIELD OF THE INVENTION

The present invention relates to a hydraulic block of an electrohydraulic power-assisted brake, the upper side of which is provided with a brake-fluid reservoir, which is fixed in place on the front surface and the rear surface of the hydraulic block in a removable manner with the aid of a front fastening apparatus/device (arrangement) and a rear fastening apparatus/device (arrangement).

BACKGROUND INFORMATION

Such hydraulic blocks are already believed to be available. One of the difficulties with these hydraulic blocks is the installation of the brake-fluid reservoir, which must be easily removable for interventions at the reservoir while limited space is available to reach the attachment of the reservoir.

In addition, the reservoir has to be connected to the hydraulic block by tight connections between the connector of the reservoir and the supply connections of the hydraulic block.

SUMMARY OF THE INVENTION

The present invention has the object of providing a hydraulic block of an electrohydraulic power-assisted brake, which is provided with an apparatus/device (arrangement) that allows for a simple, removable attachment of the brake-fluid reservoir in order to facilitate access to the installation and assembly apparatus/device (arrangement) of the reservoir on the hydraulic block.

In addition, the present invention has the object of facilitating the installation of the hydraulic block on the splash wall of the vehicle, which separates the engine compartment in which the hydraulic block is accommodated from the side of the passenger compartment in which the brake pedal that is connected to the hydraulic block by the control rod is located.

Toward this end, the present invention has as its subject matter a hydraulic block of an electrohydraulic power-assisted brake of the type defined in the previous text, which is characterized in that the front fastening apparatus/device (arrangement) is formed by a tab that projects from the underside of the brake-fluid reservoir, this tab being fastened to the front surface of the hydraulic block by a screw, and the rear fastening apparatus/device (arrangement) is formed by a tab projecting from the rear side of the reservoir, a hook of a carrier, which is fastened to the rear side of the hydraulic block and forms a support for the tab, and a clamp, which connects the tab to the hook with support on the tab.

This hydraulic block offers the advantage that it has a simple configuration with a reduced number of components and attaches easily, rapidly and effectively to the splash wall of the vehicle while it is easily possible to uninstall the brake-fluid reservoir for interventions on the reservoir or for its exchange and to then reinstall it again.

The clamp requires only minimal space in front of the splash wall in order to be brought into an engagement with the tab and the hook, and the front fastening screw is accessible to a screwdriver tool. Otherwise, the reservoir is mounted from the direction of the topside of the hydraulic block, which does not pose any difficulties and makes it possible to visually control the precise mounting.

The fastening apparatus/device (arrangement) that are part of the reservoir are the aforementioned parts, which does not complicate the formation of the reservoir. The carrier on the rear side is a piece that has multiple functions, which thus facilitates the cost-effective production and the installation while a certain acoustic decoupling is realized with the aid of the carrier produced from a plastic material, which is inserted between the plate and the hydraulic block.

According to another advantageous feature, the carrier made of a rectangular body provided with an opening for the fastening to the rear side of the hydraulic block is configured around the passageway of the control rod of the brake, and at the upper section is equipped with the hook, the upper side of which forms the support for the tab of the reservoir.

This form of the carrier, which is adapted to the hydraulic block on the one side and to the lid on the other, thus realizes an excellent interface without interfering with the installation of the hydraulic block on the splash wall.

According to another advantageous feature, the back of the carrier is provided with positioning pegs in order to reach into positioning receptacles of the rear side of the hydraulic block, and with fastening rings, which are integrated into the body, this carrier being combined with a plate, which is provided with an opening that corresponds to the passageway of the control rod, and bores, which correspond to the fastening rings, as well as with lugs for fastening the plate to the splash wall of the vehicle; the plate being placed against the carrier in order to fix the carrier in place on the hydraulic block with the aid of screws, which connect the plate to the rear surface of the hydraulic block, through the rings, in order to block the carrier.

The positioning pegs allow the carrier to be precisely positioned on the rear surface of the hydraulic block, and the fastening rings prevent the plate from compressing the carrier and allowing the plastic material to flow. Therefore, this guarantees the fastening of the plate to the carrier and that of the thereby formed component assembly to the splash wall.

According to another advantageous feature, the tab is a rectangular flat pin whose upper side has a snap-in cavity, which is restricted by a front edge, two side edges and a serrated rear edge.

This simple form facilitates the forming/injection molding, while ensuring the transversal and longitudinal snapping-in of the clamp.

According to another advantageous feature, the body of the carrier has a rectangular form with an edged opening for reaching the contour of the opening of the rear side of the hydraulic block, and is extended in the axis of the control rod of the brake to a frustoconical lid, which forms a cavity that surrounds the entrance of the control rod and its accessory parts into the hydraulic block and accommodates a sleeve fastened to the control rod.

This seemingly complex form of the carrier is nevertheless easy to produce by a molding/injection molding process by configuring the rear section with a frustoconical lid and its collar and the front section (back of the carrier), which is open on account of cavities produced in the thickness of the rectangular body and in the base of the lid.

This is even more interesting as the base of the frustoconical lid advantageously has the shape of a rim which includes a reinforcement, which is partially integrated into the thickness of the rectangular body and forms a support surface for the plate whose contour of the circular opening is supported on this base and on the rear surface of the upper and lower extensions of the body.

According to another advantageous feature, the fastening rings are made of metal and integrated into the carrier made from plastic material, the axial thickness of the rings corresponding to the axial thickness of the carrier. This combination facilitates the fastening of the carrier to the plate while squeezing of the carrier is avoided.

In an advantageous manner, the carrier includes two fastening rings, i.e. one in the upper extension and the other in the lower extension. This makes it possible to ensure the fastening using a minimum of fastening points and rings as well as screws.

According to another feature, the rectangular tab in the form of a flat pin is reinforced by ribs, which are connected to the rear side of the reservoir. This embodiment ensures the firm hold of the hydraulic reservoir on the upper side of the block.

In summary, the hydraulic block of an electrically conductive hydraulic power-assisted brake according to the present invention has the advantage that it has a simple and cost-effective configuration, is made up of a reduced number of components, and allows for easy access to the fastening apparatus/device (arrangement) of the reservoir or the hydraulic block without having to uninstall the hydraulic block or other components of the vehicle in the immediate vicinity of the hydraulic block in the engine compartment.

The fastening apparatus/device (arrangement) of the reservoir on the hydraulic block practically do not interfere with the configuration of the hydraulic block and require only a few internal threads and bores for the positioning of the front fastening apparatus/device (arrangement) and the rear fastening apparatus/device (arrangement), the latter simultaneously forming the apparatus/device (arrangement) for installing the hydraulic block on the splash wall of the vehicle.

In the following text, the present invention will be described in greater detail with the aid of a specific embodiment of a hydraulic block of an electrically conductive hydraulic power-assisted brake, which is illustrated in the appended figures.

DETAILED DESCRIPTION

The present invention has as its subject matter a hydraulic block1of an electrohydraulic power-assisted brake including a reservoir2, which is fastened to the upper side of the hydraulic block in a detachable manner in order to supply the block with brake fluid, which controls the brake circuit as a function of the brake demand.

According to the standard, the stated orientations “front”, “rear”, “upper” and “lower” relate to information pertaining to the installation position of the hydraulic block in the vehicle, which is characterized according to the axes shown inFIG. 1.

According toFIGS. 1, 2 and 3, hydraulic block1is a parallelepiped component whose rear side11, which faces the brake pedal, is attached to the splash wall which separates the engine compartment and the passenger compartment of the vehicle that is traversed by control rod3which is connected to the brake pedal.

Block1carries its electric motor4on a transverse side12, and it carries brake-fluid reservoir2on upper side14. Side12also has branches121of the brake circuits.

Upper side14(FIG. 6A) has three supply connections141, which accommodate connectors215of the base of reservoir2for the exchange of brake fluid between block1and reservoir2. Reservoir2has a filler pipe212, which is sealed by a plug213. Hydraulic block1has a function that is comparable to that of a tandem master cylinder.

Reservoir2is made up of two sections configured from a plastic material, i.e. a lower section in the form of a trough21, which is joined in connection plane23to an upper section in the form of a lid22, the upper side of which has a rippled configuration.

Base211of trough21(FIG. 4) is provided with three connectors215, which lock into place in the three supply connections141of upper side14of hydraulic block1by being joined in a tight manner with respect to the outer side. The length of reservoir2exceeds that of hydraulic block1so that rear side214of reservoir2and its base211are provided with fastening apparatus/device (arrangement)5,6beyond the length of block1for fastening reservoir2to front surface13and rear surface11of hydraulic block1.

Front fastening apparatus/device (arrangement)6(FIG. 2A) is formed by a tab61perpendicular to base211of reservoir2, which slopes in front of front surface13of block1in order to be connected thereto with the aid of a screw62, which is accommodated in an internal thread of front surface13.

Rear fastening apparatus/device (arrangement)5(FIG. 7) is made up of a tab51, projecting at a right angle, on rear side214of reservoir2, which is joined by a clamp53to a hook525of a carrier52, which is fixed in place on rear side11of hydraulic block1.

This configuration of fastening apparatus/device (arrangement)5,6of reservoir2takes into account the accessibility of front surface13of block1when the block is installed in the vehicle, the rear surface11near the splash wall being difficult to reach with a screwdriver tool.

Rear fastening apparatus/device (arrangement)5, which is made up of tab51, hook525and piece53, is a component assembly that is easy to realize and to open. Clamp53simultaneously ensures the compression of the component assembly and guarantees the tightness of the fluid connection through the interlaced configuration between reservoir2and hydraulic block1.

Tab51(FIG. 7) is a rectangular flat pin, which projects from rear side214of trough21and is reinforced there in the sense of the stiffness of its connection by reinforcing panels511on the upper side and the underside with the seam to rear side214of reservoir2.

Tab51includes on its upper side, near the free end, a snap-in cavity512having a rectangular form and a front edge513, two side edges514and a serrated rear edge515, which facilitates the control of the mounting of clamp53in cavity512.

The complementary section of this tab51of rear fastening apparatus/device (arrangement)5is a carrier52, which is provided with a hook525that is shown in detail inFIGS. 5A, 5B. Carrier52is configured from a rectangular body521(FIG. 5B) which has a width that is essentially equal to that of rear side11of block1, and a length (height) that is greater than that of the opening (not shown) of rear surface11which lets control rod3and the equipment allocated to it (shift detector, etc.) pass through.

Rectangular body521has an edged opening522in order to reach the contour of the opening of side11in that a cylindrical cavity522a(FIG. 5B) is formed, which is oriented according to axis XX of block1.

Body521has an upper extension on both sides of this opening/this cavity522aand a lower extension521a,521b, which is provided on its back (which is its front surface according to the general orientation) with two positioning pins523and fastening rings524.

Body521is a piece made of a plastic material having a certain thickness (e) in direction xx, which is formed by a circumferential wall5211and reinforcement ribs5212. The two fastening rings524are cylindrical rings made of steel, which have thickness (e) of body521and are integrated into it by molding with the aid of an injection molding process.

Upper extension521a, which is symmetrical with lower extension521b, differs therefrom by hook525. More precisely, according toFIGS. 7, 8A, 8B, hook525has a height such that its upper surface forms a support526for the accommodation of tab51in the installed position of reservoir2. Hook525, which is the complementary piece of tab51for accommodating clamp53of rear fastening apparatus/device (arrangement)5, is configured with tab51so that the underside of reservoir2is under compression with the upper side of block1. Hook525has an underside that is laterally edged by reliefs5251for the transverse retainment of clamp53.

FIG. 8Ashows the special form of clamp53, which is a spring steel strip having an Ω-cross-section whose brackets531open up in order to facilitate the passage at rear edge515of cavity512(FIG. 7) and at the not denoted rear edge of the underside of hook525, the bulbous section532covering these edges.

The blocking of clamp53between the lateral edges514and5251avoids any displacement of clamp53under the effect of the vibrations and shocks, as illustrated inFIG. 8B.

Body521of the carrier carries frustoconical lid54in a fixedly connected manner, which surrounds cylindrical cavity522aand is provided with an axial opening541on the front side for the passage of control rod3and its supplementary parts.

Base542of the frustoconical lid is formed by a reinforcement rim, which is partially integrated into the thickness of rectangular body521(FIG. 5B). Its thickness has reinforcement ribs543, which are visible on the back.

Frustoconical lid54has a cross-section that is suitable for accommodating the various equipment that surrounds control rod3at the connection of control rod3to hydraulic block1. These are sensors and other devices, which are not described in detail here, are mounted on the hydraulic block and elevated at rear surface11around axis xx of control rod3in order to detect its movement and to supply electrical signals that represent the brake request (intensity, speed). Frustoconical lid54accommodates sleeve545, which surrounds control rod3(FIG. 1).

Carrier52is fixed in place on hydraulic block1by a plate7(FIG. 5C), which is used to attach component assembly1,2to the splash wall of the vehicle.

Plate7is a rectangular metal plate having a circular opening71for covering lid54and for supporting itself on the rear surface of body521of the carrier and rim542. Plate7carries two or four threaded lugs72for its attachment to the splash wall, and two bores73, which match fastening rings524of carrier52in order to accommodate a fastening screw74, which mounts carrier52through plate7on rear surface11of block1, as illustrated inFIGS. 6A, 6B.

After plate7has been fixed in place on block1, reservoir2is mounted on block1with the aid of its fastening apparatus/device (arrangement)5,6and the component assembly (1,2,7) is then attached to the splash wall. Reservoir2is able to be fixed in place on block1even after the block has been attached to the splash wall.