阅读说明：本技术 配备有包括受保护通风口的密封系统的机动车辆的控制装置 (Control device for a motor vehicle equipped with a sealing system comprising a protected vent ) 是由 让·菲利普·瓦赞 布鲁诺·科瑞特尔 蒂埃里·西德尔 于 2018-05-17 设计创作，主要内容包括：本发明涉及一种用于机动车辆的控制装置,其包括控制杆、密封装置(20)以及管道(34),该控制杆轴向滑动地从该控制装置的主体(2)伸出,该密封装置在闭合该控制装置的内部空间(42)的情况下固定到该主体(2)并固定到该控制杆,该管道通向该内部空间(42)以允许该内部空间(42)中的空气流向该控制装置的外部。该控制装置的显著之处在于,包括中间腔室(30),该管道(34)形成由该内部空间(42)流向该中间腔室(30)顶部的上部空气通道,并且,该中间腔室(30)具有设置在该腔室(30)底部的流向外部的下部空气通道(36)。(The invention relates to a control device for a motor vehicle, comprising a control rod that protrudes axially slidingly from a body (2) of the control device, a sealing device (20) fixed to the body (2) with an internal space (42) of the control device closed and to the control rod, and a duct (34) that opens into the internal space (42) to allow the air in the internal space (42) to flow towards the outside of the control device. The control device is distinguished by comprising an intermediate chamber (30), the duct (34) forming an upper air passage from the interior space (42) to the top of the intermediate chamber (30), and the intermediate chamber (30) having a lower, outwardly flowing air passage (36) arranged at the bottom of the chamber (30).)

1. A control device for a motor vehicle, comprising a control rod (14) projecting axially slidingly from a body (2) of the control device, a sealing device (20) fixed to the body (2) and to the control rod (14) with an internal space (42) of the control device closed, and a duct (34) open to the internal space (42) to allow the flow of air from the internal space (42) to the outside of the control device, characterized in that it comprises an intermediate chamber (30, 130), the duct (34) forming an upper air passage open from the internal space (42) to the top of the intermediate chamber (30, 130), and in that the intermediate chamber (30, 130) has a lower air passage (36) open to the outside, provided at the bottom of the chamber (30, 130), the top and bottom are defined relative to the direction of gravity.

2. Control device according to claim 1, characterized in that the duct (34) comprises a plurality of channels arranged in parallel, each of which has a reduced section with respect to the section of the lower channel (36).

3. Control device according to claim 1 or 2, characterized in that the duct (34) is constituted by a groove formed on the outer contour of the front portion (40) of the body (2).

4. Control device according to any one of the preceding claims, characterized in that the intermediate chamber (30, 130) has an annular shape arranged around the rod (14).

5. A control device according to claim 4, characterised in that the intermediate chamber (30) is provided between a flange (26) of the rear end of a bellows made of elastomer and forming the sealing means (20) and a front circular portion (40) of the body (2).

6. A control device according to claim 5, characterised in that the intermediate chamber (30) is formed in an external annular groove of a front circular portion (40) of the body (2).

7. Control device according to any one of claims 1 to 4, characterized in that the intermediate chamber (130) is formed in the front part (40) of the body (2).

8. Control device according to claim 7, characterized in that said intermediate chamber (130) has an axially elongated shape, closed at the front by a rear flange (26) of said sealing means (20).

9. Hydraulic control device of a clutch of a motor vehicle, characterized in that it comprises a control device according to any one of the preceding claims.

10. A motor vehicle equipped with a hydraulic control apparatus, characterized in that the apparatus comprises a control device for controlling a clutch of the vehicle according to any one of claims 1 to 8.

Technical Field

The present invention relates to a control device of a motor vehicle comprising a rod axially projecting from a body, the control device being equipped with a sealing system, and to a hydraulic control device for controlling a clutch and to a motor vehicle comprising such a control device.

Background

Some motor vehicle controls include a jack having a body with a bore that receives a piston, the jack receiving fluid pressure to axially push a control rod extending from the body in a direction commonly referred to as the front side.

In particular, the vehicle may include a master cylinder actuated by a clutch pedal that delivers pressure of fluid into a slave cylinder to move a lever acting on a disconnect fork. As a variant, the clutch control means may be automatic, actuated by motorized means.

A known sealing system between the rod and the body, in particular proposed by document GB-B-2163292, comprises a protective bellows made of elastomer, having one end fixed around the body and the other end fixed around the front side of the rod, so as to follow the movement of the rod while maintaining a closed internal space.

Another known sealing system, particularly proposed by document FR-B1-2741401, comprises an expandable membrane having one end fixed around the body and the other end fixed around the rear side of the rod, so that it rolls up by retracting itself when the rod is slid backwards, and unfolds backwards when the rod is extended forwards.

Another known sealing system, particularly proposed by document EP-B1-2039968, comprises a rigid tube sliding in a seal fixed to the body, which is connected to the rod by a flexible connecting element so as to follow the movement of the rod.

These different types of sealing systems have a closed interior space that varies in response to movement of the rod. It is known to provide vents to the interior space to prevent pressure drops or overpressures during movement of the rod causing the spatial variation, which could damage certain components such as radial sealing rings or cause operational failure.

The diameter of the vent holes is typically limited to avoid excessive passage of impurities. However, in certain environments where dirt is heavy or moist, particularly environments filled with sand, the vent holes may draw in some small impurities during the increase in internal space. Thus, with the accumulation of these impurities, there is a risk of hydraulic piston scraping, piston seizure, leakage at dynamic seals, or oxidation upon moisture ingress.

In a variant, it is known to make a sealing bellows for a motor vehicle control device, which has a substantially fixed space. In this case, it is still necessary to provide a miniature leakage duct to avoid overpressure or depressurization of the interior space, in particular due to changes in the air pressure or temperature, so as to allow very small air flow rates. For this purpose, small gaps can be produced, in particular, in the contour of the end flange which receives the sealing bellows fixed above.

However, such pipes with very small cross-sections present problems due to their easy clogging, especially in greasy or humid environments where dust can accumulate and clog the channels. In the case of a small change in the humidity entering the interior space, the ventilation of the space is insufficient for subsequent drying.

Disclosure of Invention

The invention is particularly intended to avoid these disadvantages of the prior art.

To this end, the invention proposes a control device for a motor vehicle comprising a control rod projecting axially slidingly from a body of the control device, a sealing device fixed to the body and to the control rod with an internal space of the control device closed, and a duct open to the internal space to allow air to flow from the internal space to the outside of the control device, the control device being notable in that it comprises an intermediate chamber forming an upper air passage open from the internal space to the top of the intermediate chamber, and in that the intermediate chamber has a lower air passage open to the outside arranged at the bottom of the chamber, the top and bottom being defined with respect to the direction of gravity.

The advantage of this control device is that the intermediate chamber constitutes a stable separation chamber which can optionally receive impurities such as dust or moisture entering through the lower channels provided at the bottom, which impurities are then deposited inside the chamber due to the difficulty of rising again to the upper part. Thus, there is little risk of these impurities entering the ducts leading to the inner space of the control device.

With a stable cavity made in an economical way by moulding, the inner space is protected in a simple and effective way by avoiding the ingress of impurities.

The control device according to the invention may also comprise one or more of the following features which can be combined with each other.

Advantageously, the duct has a plurality of channels arranged in parallel, each channel having a reduced section with respect to the section of the lower channel.

Advantageously, the duct is constituted by a groove formed on the outer profile of the front part of the body.

In particular, the intermediate chamber may have an annular shape arranged around the control rod.

According to an embodiment, the intermediate chamber is provided between a flange of the rear end of the bellows and the front circular portion of the body, the bellows being made of elastomer and forming the sealing means.

In this case, the intermediate chamber may be formed in an outer annular groove of the front circular portion of the body.

According to another embodiment, the intermediate chamber is formed in the front portion of the body.

In this case, the intermediate chamber may have an axially elongated shape which is closed at the front by a rear flange of the sealing means.

The invention also relates to a hydraulic control device of a clutch of a motor vehicle, which is distinguished by comprising a control device having any one of the aforementioned features.

Furthermore, the invention relates to a motor vehicle equipped with a hydraulic control device comprising a control device for controlling a vehicle clutch having any one of the aforementioned features.

Drawings

The invention will be better understood and other objects, features, details and advantages thereof will become more clearly apparent in the course of the following detailed description, with reference to the accompanying drawings, which are given by way of example only of an embodiment of the present invention and in which:

figure 1 is an axial section of a clutch slave cylinder forming a control device according to the prior art;

figure 2 is a partial axial section of a clutch slave cylinder forming a control device according to the present invention;

figures 3 and 4 are transverse cross-sections of the control device along section iii-iii and section IV-IV, respectively;

figures 5 and 6 are detailed views of figures 2 and 3, respectively;

figures 7 and 8 are a partial axial section and a transverse section along the section VIII-VIII, respectively, of the control device according to the variant; and is

Figure 9 is a partial axial section of a control device according to a variant of the control device shown in figure 7.

Detailed Description

Fig. 1 shows a body 2 of a slave cylinder of a clutch control device, which body 2, formed by moulding of a plastic material, comprises a first sleeve 6 arranged to receive a hydraulic supply conduit, and a second sleeve 4 arranged to receive an exhaust.

The body 2 has a hydraulic chamber 10 which receives, on the front side indicated by the arrow "AV", a piston 8 sliding in an axial hole. The helical compression spring 12 continues to push the piston 8 forward.

The piston 8 extends forward by means of a control rod 14, which control rod 14 has a sleeve 16 on the front side, the end of which sleeve 16 forms a ball joint receiving a front bowl 18, which front bowl 18 is arranged to press tightly against the control fork of a clutch of a vehicle transmission.

The protection bellows 20 made of elastomer has, at its rear end, a flange 26 surrounding a circular front portion 40 of the body 2, the flange 26 bearing axially on the front surface of the circular boss 32 of the body. The rear flange 26 has a continuous inner flange 22, which inner flange 22 is inserted into a groove of the rounded end of the body 2 to ensure engagement and sealing. The front end of the protective bellows 20 has a front flange 28 surrounding an annular portion of the front bowl 18 to also ensure engagement and sealing.

The external coil spring 24 surrounds the entire bellows 20 with the flanges 26, 28 fastened to protect the bellows and ensure its engagement. In particular, the external spring 24 may replace the internal compression spring 12 for pushing the piston 8 forward.

The air circulation duct between the outside and the inner space 42 of the bellows is formed by making a small slit in the circular part of the body 2 or of the front bowl 18, which circular part of the body 2 and of the front bowl 18 receives the flanges 26, 28 of the bellows 20. In heavily dusty environments, particularly in the presence of moisture or greasy objects, dust can accumulate to clog ducts and render these vents ineffective.

Figures 2, 3, 4, 5 and 6 show a front end comprising a body 2 comprising a circular portion 40, the circular portion 40 having externally an annular groove covered by the rear flange 26, the annular groove forming the intermediate stabilization chamber 30. The piston 8 and the control rod 14 are not shown in these figures.

The five upper longitudinal grooves 34 form mini-leakage ducts each having a "V" shaped cross-section formed at the top of the front circular portion 40 of the body 2, between the annular groove of the stabilization chamber 30 and the inner space 42 of the bellows 20 the number and cross-section of the upper grooves 34 forming the ducts are arranged to allow a sufficient amount of air flow while filtering impurities.

The lower longitudinal groove 36, formed at the bottom of the front circular portion 40 of the body 2, at the rear of the annular groove of the stabilization chamber 30, constitutes a passage to the outside, with a sufficient section to allow the air flow through the stabilization chamber to the inner space 42 when the control device is moved.

As the control rod 14 is extended, the interior space 42 increases and draws air in through the lower recess 36. The stabilization chamber 30 has a sufficient height and sufficient passage portions on both sides of its circular contour to allow air to flow therein at a low speed and make it difficult for foreign substances or water droplets from the outside to reach the top, especially by a vortex or capillary action. The upper part of the stabilization chamber 30 is thus kept clean and dry.

The cross section of each upper groove 34, which is reduced with respect to the cross section of the lower groove 36, filters, if necessary, the impurities entering the top of the stabilization chamber 30.

Then, as the control rod 14 is retracted, the interior space 42 decreases and vents air to the exterior through the stabilization chamber 30. Therefore, by means of the lower groove 36 along the arrow F, the impurities that may have been deposited in the stabilization chamber 30 at the last air entry are easily expelled by the air flow by means of gravity. In the event that incoming water droplets or moisture condense, the droplets are also easily drained outwardly through the lower groove 36.

As a variant, the stabilization chamber 30 may be constituted by an internal circular groove formed in the rear flange 26 of the bellows 20.

Fig. 7 and 8 show a circular boss 32 formed at the front of the body 2, the boss 32 extending over a greater axial distance and having, internally, an annular stabilizing chamber 130 of axial shape, which is open towards the front. In moulding the body 2, the stabilization chamber 130 is formed by a circular core of the mould entering the chamber, which can be demoulded by sliding axially forward.

A plurality of upper longitudinal grooves 34 are formed on the body 2 in front of the circular protrusion 32, which upper longitudinal grooves 34 form a conduit between the stabilization chamber 130 and the inner space 42 below the rear flange 26 of the bellows 20. An aperture located behind the stabilization chamber 130 forms an externally open lower channel 36 through the circular boss 32.

Fig. 9 shows the rear flange 26 of the bellows 20 with an internal circular protrusion 50, the internal circular protrusion 50 comprising an inclined rear surface and a front surface in a transverse plane, the protrusion 50 fitting into a circular groove of the same cross-section formed around the front circular portion of the body 40.

The inclined rear surface of the internal projection 50 allows the rear flange 26 to be inserted into the body 2 by pushing the rear flange 26 backwards until the projection falls into its circular recess where the internal projection 50 is engaged and secured by its lateral front surface which prevents the internal projection 50 from being withdrawn.

As a variant shown in fig. 7, the upper longitudinal groove 36 formed on top of the front circular portion of the body 40 follows the contour of the circular groove to pass under the inner protrusion 50 of the bellows 20 provided in this groove, thus forming a conduit connecting the stabilization chamber 130 to the inner space 42.

By this means of sufficiently fastening the rear flange 26 to the main body 2, it is possible to eliminate the external helical spring 24, which in the previous variant presses on this flange to keep it in place.

In general, a stabilization chamber 30, 130 having any shape may be manufactured, including a lower passage 36 leading to the exterior and an upper passage 34 leading to the interior space 42. These shapes may be concentric about the axis of the bellows 20, or may be non-concentric and disposed on the sides of the bellows 20. The sealing of the stabilization chambers 30, 130 may also be accomplished by any type of method.

In particular, the bellows 20 may be arranged to have a substantially constant inner space 42 during movement of the control device, the stabilization chamber 30, 130 serving as a necessary small air passage, especially when the atmospheric pressure or temperature changes.