ECO-EFFICIENT MOUNTING OF A MASTER CYLINDER TO THE BODY OF A MOTOR VEHICLE

Abstract

ECO-EFFICIENT MOUNTING OF A MASTER CYLINDER TO THE BODY OF A MOTOR VEHICLE The present invention relates to a master cylinder (2) for a motor vehicle clutch system, comprising: - a housing (4) having means for mounting said housing to a body of the motor vehicle, said means for mounting including an opening (6.2) for the passage of a mounting screw intended to mount the master cylinder to said body; and - a sliding rod (8) having a proximal end forming a piston housed within the housing, and a distal end (8.1) forming at least one eyelet (8.2) for retaining said rod to an element of the motor vehicle clutch system; remarkable in that the means for mounting further include a centering pin (6.1) extending from the housing, intended to engage in a corresponding hole in the body of the motor vehicle. (Figure to be published with the abbreviation: Figure 1)

Description

Title of the invention: ECO-EFFICIENT MOUNTING OF A MASTER CYLINDER TO THE BODY OF A VEHICLE TOMOBILE technical field

[0001] The present invention relates to the field of motor vehicles, more particularly to the field of master cylinders for motor vehicles. Previous technique

[0002] The use of master cylinders is well known in the automotive field, particularly in clutch systems. They generally comprise a housing with a piston guided on a guide element, which is movable by a piston rod.

[0003] These master cylinders control the hydraulic clutch by connecting the piston rod to the vehicle's clutch pedal. A pressure line connects the piston rod to a slave cylinder, thus transmitting the pressure generated by depressing the clutch pedal to the slave cylinder. This results in an actuation force on a release bearing, allowing the clutch pressure plate to be separated from the cam plate, thereby disengaging the internal combustion engine from the vehicle's transmission.

[0004] The published patent document EP 0 790 427 B1 discloses a master cylinder configured to control a hydraulic clutch in a motor vehicle; it comprises a housing and two points of attachment by screwing the housing to a structure of the motor vehicle.

[0005] However, the master cylinder disclosed in the document is configured to be fixed to the vehicle structure by means of two clamping screws. Therefore, there is room for improvement in order to make the master cylinder fixing more economical. Description of the invention

[0006] The present invention aims to overcome at least one of the drawbacks of the aforementioned prior art. More specifically, the invention aims to provide a simple and efficient solution for the economically efficient attachment of a master cylinder to the body of a motor vehicle.

[0007] To this end, the invention relates to a master cylinder for a motor vehicle clutch system, comprising: - a housing comprising means for attaching said housing to the body of the motor vehicle, said means of attachment comprising an opening for a fixing screw intended to attach the master cylinder to said body; and - a sliding rod having a proximal end forming a piston housed within the casing, and a distal end forming at least one eyelet for retaining said rod to an element of the motor vehicle's clutch system; remarkable in that the fastening means include, in addition, a centering pin extending from the housing, intended to engage in a corresponding hole in the body of the motor vehicle.

[0008] Preferably, the element of the motor vehicle's clutch system comprising a clutch pedal.

[0009] According to one embodiment, the centering pin comprises a cylindrical shape having a diameter between 5 and 20 mm.

[0010] According to one embodiment, the means for fixing the housing to the casing comprise exclusively a single hole for the fixing screw.

[0011] According to one embodiment, the centering pin extends transversely to a main axis of said master cylinder, said main axis being coincident with an axis of the sliding rod.

[0012] According to one embodiment, the centering pin is aligned with the passage hole of the fixing screw, along a straight line arranged substantially parallel to the main axis of the master cylinder.

[0013] According to one embodiment, the centering pin is formed as a single piece with the housing, and extends from said housing over a length equal to at least 10 mm.

[0014] The invention also relates to a motor vehicle comprising a clutch system provided with a master cylinder fixed to a body of said motor vehicle, remarkable in that said master cylinder is according to the invention.

[0015] According to one embodiment, the housing includes a mounting bracket having a first hole receiving the centering pin extending from the master cylinder housing, and a second hole receiving the fixing screw passing through the orifice of the housing.

[0016] According to one embodiment, the fixing of the master cylinder to the casing is exclusively ensured by a single fixing screw.

[0017] Preferably, the fixing screw is parallel to the centering pin, in the normal mounting position of the master cylinder on the body of the motor vehicle.

[0018] The invention also relates to a method of mounting a master cylinder on a motor vehicle, remarkable in that said motor vehicle being according to the invention, said method comprising the following steps: - insertion of the centering pin into a first hole in the body of the motor vehicle; - Inserting the fixing screw successively through the hole in the housing and a second hole in the case; - fixing the master cylinder to the casing by screwing the casing to said casing using the fixing screw passing through the second hole and a corresponding nut.

[0019] The measures of the invention are advantageous in that the mounting of the master cylinder according to the invention on the body of the motor vehicle is an eco-efficient operation allowing to considerably reduce costs, while ensuring a rigid fixing of the master cylinder on the body.

[0020] Cost savings are achieved by reducing the number of components required, in particular by eliminating the need for a screw, nut, and washer, which are not necessary for attaching the master cylinder according to the present invention (in contrast to prior art solutions). These savings are also achieved by eliminating the costs associated with machining the first hole, resulting in saving one tapping operation. Brief description of the drawings

[0021] [Fig-1] represents a perspective view of a master cylinder according to the invention;

[0022] [Fig.2] represents a perspective view of the master cylinder of the [Fig.1] mounted on a motor vehicle body. Detailed description

[0023] Fig. 1 represents a perspective view of a master cylinder 2 according to the invention, which allows hydraulic control of a slave cylinder (not shown) preferably belonging to a clutch system of the motor vehicle.

[0024] The master cylinder 2 includes a housing 4 which has fastening means 6 enabling it to be fixed to a body of the motor vehicle, said housing 4 housing a piston (not shown) corresponding to a proximal end of a sliding rod 8 of the master cylinder 2, the latter also includes a distal end 8.1 formed by at least one retaining eyelet 8.2, and preferably by two retaining eyelets 8.2 of said rod 8 to a clutch pedal of the motor vehicle.

[0025] Advantageously, the mounting means 6 for the housing 4 include a centering pin 6.1 and a single hole 6.2 for the mounting screw, enabling the master cylinder 2 to be mounted and secured to the body. Indeed, the master cylinder 2 is exclusively provided with a single hole 6.2 for the passage of a single mounting screw, which alone secures the housing 4 to the body. This is made possible in particular by the centering pin 6.1, which eliminates the need for two mounting screws, thus resulting in considerable savings in terms of the components required for said fastening (screw, nut, and corresponding washer).

[0026] Preferably, the centering pin 6.1 is formed as a single unit with the housing 4, and extends transversely from said housing 4, in a direction substantially perpendicular to a principal axis A of said master cylinder 2, said principal axis A cor corresponding to an axis of revolution of the sliding rod 8.

[0027] The centering pin 6.1 extends over a length L equal to less than 10 mm, and preferably between 10 mm and 50 mm. Said pin 6.1 preferably comprising a cylindrical shape having a diameter D between 5 and 20 mm.

[0028] It can be seen that the centering pin 6.1 is aligned with the orifice 6.2 for the passage of the fixing screw, along a straight line B arranged substantially parallel to the main axis A of the master cylinder 2, or inclined at most 20° with respect to said main axis A.

[0029] Fig. 2 represents a perspective view of the master cylinder 2 of Fig. 1 mounted on a body 10 of a motor vehicle 1.

[0030] Thanks to the centering pin 6.1, the master cylinder 2 is secured to the housing 10 exclusively by a single fixing screw 7 which extends parallel to the centering pin 6.1, in the normal mounting position of the master cylinder 2 illustrated in [Fig. 2]. The fixing screw 7 is shown schematically and in a simplified manner without threads, in order to facilitate reading [Fig. 2].

[0031] The case 10 preferably includes a fixing tab 12 having a first hole 12.1 receiving the centering pin 6.1, and a second hole 12.2 receiving the fixing screw 7 passing through the orifice 6.2 of the housing 4.

[0032] The first hole 12.1 corresponds preferably to a smooth hole, in that its inner surface is not tapped like the second hole 12.2 which allows the engagement of the fixing screw 7.

[0033] Mounting the master cylinder 2 on the housing 10 is advantageously simplified. It comprises a first step of inserting the pin 6.1 into the first hole 6.1. This positions the housing 4 and locks all its degrees of freedom (except for rotation about the axis of the first hole 6.1). This last degree of freedom is then eliminated by tightening the fixing screw 7 after its successive insertion through the opening in the housing 4 and the second hole 6.2. A corresponding nut (not shown in [Fig. 2]) secures the assembly to the screw 7.

[0034] In this configuration, the mounting of the master cylinder 2 on the motor vehicle is eco-efficient, in that it is both economically effective and environmentally friendly. This is achieved in particular thanks to the presence of the centering pin 6.1, which eliminates the need for an additional screw, nut, and washer beyond the single required fixing screw 7. The master cylinder 2 is then held securely in place and properly fixed to the body 10 of the motor vehicle 1 by the sole combination of the fixing screw 7 and the centering pin 6.1.

Claims

Demands

1. Master cylinder (2) for a motor vehicle clutch system (1), comprising: - a housing (4) having means (6) for fixing said housing (4) to a body (10) of the motor vehicle (1), said means (6) including an opening (6.2) for the passage of a fixing screw (7) for fixing the master cylinder (2) to said body (10); and - a sliding rod (8) having a proximal end forming a piston housed within the housing (4), and a distal end (8.1) forming at least one eyelet (8.2) for retaining said rod (8) to an element of the motor vehicle clutch system (1); characterized in that the fastening means (6) further include a centering pin (6.1) extending from the housing (4), intended to engage in a corresponding hole (12.1) in the body (10) of the motor vehicle (1).

2. Master cylinder (2) according to claim 1, wherein the centering pin (6.1) comprises a cylindrical shape having a diameter (D) between 5 and 20 mm.

3. Master cylinder (2) according to any one of claims 1 and 2, wherein the means for fixing (6) the housing (4) to the casing (10) comprise exclusively a single orifice (6.2) for the passage of the fixing screw (7).

4. Master cylinder (2) according to any one of claims 1 to 3, wherein the centering pin (6.1) extends transversely to a main axis (A) of said master cylinder (2), said main axis (A) being coincident with an axis of the sliding rod (8).

5. Master cylinder (2) according to claim 4, wherein the centering pin (6.1) is aligned with the orifice (6.2) for the passage of the fixing screw (7), along a straight line (B) disposed substantially parallel to the main axis (A) of the master cylinder (2).

6. Master cylinder (2) according to any one of claims 1 to 5, wherein the centering pin (6.1) is formed as one piece with the housing (4), and extends from said housing (4) over a length (L) equal to at least 10 mm.

7. Motor vehicle (1) comprising a clutch system having a master cylinder (2) fixed to a body (10) of said motor vehicle (1), characterized in that said master cylinder (2) is according to any one of claims 1 to 6.

8. Motor vehicle (1) according to claim 7, wherein the body

9.

10. (10) includes a mounting bracket (12) having a first hole (12.1) receiving the centering pin (6.1) extending from the housing (4) of the master cylinder (2), and a second hole (6.2) receiving the fixing screw (7) passing through the orifice (6.2) of the housing (4). Motor vehicle (1) according to any one of claims 7 and 8, wherein the fixing of the master cylinder (2) to the body (10) is exclusively ensured by a single fixing screw (7). Method of mounting a master cylinder (2) on a motor vehicle (1), characterized in that said motor vehicle (1) being according to any one of claims 7 to 9, said method comprising the following steps: - insertion of the centering pin (6.1) into a first hole (12.1) in the body of the motor vehicle (2); - insertion of the fixing screw (7) successively through the orifice (6.2) of the housing (4) and a second hole (12.2) of the case (10); - fixing the master cylinder (2) on the casing (10) by screwing the housing (4) to said casing (10) by means of the fixing screw (7) passing through the second hole (12.2) and a corresponding nut.

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