FR3044368A1 - DEVICE FOR CONTROLLING AN ORGAN TO BE CHECKED BY TWO CONCENTRIC AND INDEPENDENT CYLINDERS - Google Patents

Abstract

A control device (DC) comprises a body (CD) comprising: a first cylinder (CY1) comprising a first chamber (CH1) communicating with a first channel (CA1) in which a fluid flows under the control of a first control and housing a first piston (P1) having a first shaft (A1) adapted to translate a cup (CO) acting on a member to be controlled, and - a second cylinder (CY2), housed in the first chamber (CH1) and part in an open housing (LO) of the first piston (P1), and having a second chamber (CH2) communicating with a second channel (CA2) in which a fluid flows under the control of the first control member and / or a second control member and housing a second piston (P2) having a second shaft (A2) housed partly in the open housing (LO) and adapted to translate the cup (CO).

Description

The invention relates to the control of organs by control members via a fluidic control device.

As known to those skilled in the art, in many systems or installations fluidic control devices are used to transmit an action of a control member to an organ to be controlled. For example, in some vehicles, possibly of automobile type, the control member may be a brake pedal and the member to be tested may be a brake pad, or the control member may be a clutch pedal and the member to be controlled may be a clutch fork, or the control member may be a steering wheel and the member to be controlled may be a wheel pivot member.

This type of control device generally comprises a body comprising a cylinder comprising a chamber which communicates with a channel in which a fluid circulates under the control of a control member and which houses in translation a piston having a shaft suitable for translating a workpiece. intended to act on the organ to be controlled. The fluid may be a gas, such as for example air, or a liquid, such as oil or water.

When a problem occurs on the control device, such as a leakage of fluid or breakage of the shaft secured to the piston, it becomes difficult, if not impossible, to act properly on the organ to be controlled, which can prove to be very dangerous and therefore does not offer an optimal security of operation.

In order to improve the situation, it has been proposed, particularly in patent document EP 2876323, to define in parallel in the body of the control device two chambers each housing in translation a piston having a shaft adapted to translate a cup intended to act. on the organ to be controlled, and each fed by a fluid conduit. Thus, if a problem occurs in one of the two parallel chambers, it remains possible to act on the organ to be controlled via the other chamber and the associated piston. However, such an arrangement greatly increases the size and weight of the control device, which prevents its use in many systems. The invention is therefore particularly intended to improve the situation.

It proposes for this purpose a control device, intended to control a control member to be controlled by a first control member, and comprising a body having a first cylinder comprising a first chamber communicating with a first channel in which a fluid circulates. under the control of at least the first control member and housing in translation a first piston having a first shaft adapted to translate a cup intended to act on the organ to be controlled.

This device is characterized in that its body comprises a second cylinder, housed in the first chamber and partly in an open housing defined in the first piston, and comprising a second chamber communicating with a second channel in which a fluid circulates under the control of the first control member and / or a second control member and housing in translation a second piston having a second shaft housed partly in the open housing and adapted to translate the cup.

With such a concentric cylinder control device one inside the other, and therefore reduced space, it is now ensured that in case of problems occurring in one of the two rooms, we can continue to act on the organ to be controlled via the other chamber and the associated piston, without this limiting the control function.

The device according to the invention may comprise other characteristics that can be taken separately or in combination, and in particular: it may comprise a first spring installed in the first chamber around the second cylinder upstream of the first piston, on the opposite side to the first tree, in order to induce a pre-charge of the cup. Alternatively, it may comprise a first spring installed in the first chamber around the first shaft to induce a return of the first piston in a rest position; it may comprise a second spring installed in the second chamber upstream of the second piston, on the opposite side to the second shaft, in order to induce a pre-charge of the cup. Alternatively, it may comprise a second spring installed in the second chamber around the second shaft to induce a return of the second piston in a rest position; - It can include a bellows secured to the cup and the body, and partially surrounding the first tree; the first chamber may comprise on the side of the cup a ring surrounding the first shaft and defining a stop; - The second chamber can be closed, at an end facing the cup, by a sleeve provided with a hole through which the second shaft and defining a stop. The invention also proposes a vehicle, possibly of automotive type, and comprising at least one organ to be inspected, at least one first control member intended to control the organ to be inspected, and at least one control device of the type of the one presented. above.

For example, such a control member may be selected from (at least) a brake pad, a clutch fork and a wheel pivot member. Other characteristics and advantages of the invention will appear on examining the detailed description below, and the accompanying drawings (obtained in CAD / CAD ("Computer Aided Design / Computer Aided Drawing"), of where the apparently discontinuous character of certain lines and the gray levels), in which: FIG. 1 schematically illustrates, in a sectional view, a first exemplary embodiment of a control device according to the invention, FIG. 2 schematically illustrates, in a sectional view, a second exemplary embodiment of a control device according to the invention, - Figure 3 schematically illustrates, in a perspective view, the control device of Figure 1, - the FIG. 4 schematically illustrates, in a sectional view, an exemplary embodiment of a first piston of the control device of FIG. 1; FIG. 5 schematically illustrates, in a sectional view, an example of embodiment of a second piston of the control device of FIG. 1, - FIGS. 6A and 6B schematically illustrate, respectively in side and front views, an exemplary embodiment of a ring of the control device of FIG. 1, and FIGS. 7A and 7B schematically illustrate, respectively in side and front views, an exemplary embodiment of a socket of the control device of FIG. 1. The object of the invention is in particular to propose a DC fluidic control device and for controlling a member to be controlled by at least one control member.

In what follows, it is considered, by way of non-limiting example, that the DC control device is intended to be part of a vehicle, possibly of automotive type, such as a car. But the invention is not limited to this application. It concerns indeed any system, any installation, including industrial, and any building comprising at least one member to be controlled by at least one control member via a fluidic control device.

Furthermore, it is considered in the following, by way of non-limiting example, that the control member is a brake pedal and the member to be tested is a brake pad. But the invention is not limited to this application. Thus, the control member could be a clutch pedal and the body to be controlled could be a clutch fork, or the control member could be a steering wheel and the body to be controlled could be a pivoting member wheels, for example.

FIGS. 1 and 2 show diagrammatically two nonlimiting exemplary embodiments of a DC control device according to the invention. As illustrated, a DC control device according to the invention comprises at least one body CD, a first piston P1, a second piston P2 and a cup CO intended to act on the organ to be controlled.

In what follows and the foregoing, the notion of "before" qualifies an orientation towards the cup CO and therefore toward the organ to be controlled, and the notion of "back" qualifies an orientation opposed to the cup CO .

The body CD comprises first CY1 and second CY2 concentric cylinders.

The first cylinder CY1 (external) is defined by a wall of the body CD and comprises a first chamber CH1 which communicates with a first channel CA1 and translates a first piston P1. A fluid flows in the first channel CA1, and therefore also in a portion of the first chamber CH1, under the control of at least a first control member. This fluid may be a gas, such as for example air, or a liquid, such as oil or water.

The first piston P1 has a rear portion PR1, which defines a first compression head, and a first shaft A1, which extends forward this first compression head PR1 and comprises a front portion (or free end) PV1 adapted to translate the cup CO. Moreover, and as illustrated in FIG. 4, the first piston P1 comprises, in its first compression head PR1 and its first shaft A1, an internal housing LO which is open at its two opposite ends (rear and front), to communicate with the outside via two holes T1 and T2. The outer diameter of the first compression head PR1 is substantially equal, by a value slightly less than the diameter of the first chamber CH1. The outer diameter of the first shaft A1 is strictly smaller than the outer diameter of the first compression head PR1.

The second cylinder CY2 (internal) is fixedly housed in the first chamber CH1 of the first cylinder CY1 (external) and partly in the open housing LO. In other words, the second cylinder CY2 passes through at least the hole T1 of the first piston P1. It will be noted that this second cylinder CY2 can be either defined by an internal wall of the body CD, or an insert in the body CD and secured to the latter (CD).

This second cylinder CY2 comprises a second chamber CH2 which communicates with a second channel CA2 and translates a second piston P2. A fluid flows in the second channel CA2, and thus also in a part of the second chamber CH2, under the control of the first control member and / or a second control member. This fluid may be a gas, such as for example air, or a liquid, such as oil or water.

As illustrated in FIG. 5, the second piston P2 has a rear portion PR2, which defines a second compression head, and a second shaft A2, which extends this PR2 compression head forward and comprises a front portion (or end free) PV2 clean to translate the CO cup. The outer diameter of the second compression head PR2 is substantially equal, by a value slightly less than the diameter of the second chamber CH2. The outer diameter of the second shaft A2 is strictly smaller than the outer diameter of the second compression head PR2.

In the example which is described here without limitation, the first control member is a brake pedal and the body to be tested is a brake pad. The possible second control member may be an auxiliary brake pedal or an actuator which may, for example, be controlled (here) by the driver of the vehicle by means of a dedicated control member (for example a push button or a lever) or a selection of a dedicated option in a menu displayed on a vehicle screen and preferably direct access. Alternatively or in addition, this second control member may optionally be automatically controlled in case of detection of a failure of the first control member or the first chamber CH1. It will be understood that in this case this possible second control member is used in case of failure in the first chamber CH1 (problem on the first piston P1 and / or sealing).

According to the embodiment envisaged, the first control member can control the translations either of only the first piston P1, or simultaneously of the first P1 and second P2 pistons, and the possible second control member can control the translations either only of the only one. second piston P2, or simultaneously first P1 and second P2 pistons. As a result, whatever the embodiment considered, it is ensured that in the event of a problem occurring in one of the two chambers CH1 and CH2, it will be possible to continue to act on the organ to be controlled via the other chamber. and the associated piston, without this limiting the control function. Indeed, in case of a problem in the first chamber CH1, the second chamber CH2 and the second piston P2 continue to cooperate to control the translation of the cup CO, and if there is a problem in the second chamber CH2, the first chamber CH1 and the first piston P1 continue to cooperate to control the translation of the cup CO.

Moreover, thanks to the fact that the cylinders CY1 and CY2 are concentric (or nested one inside the other), the body CD has a small bulk, which makes it possible to use its DC control device in many systems, including those with large footprint.

In order to avoid fluid leaks, out of the first chamber CH1, it is advantageous, as illustrated in FIGS. 1 and 4, for the compression head PR1 of the first piston P1 to be equipped with at least one seal , for example toric type. In the example illustrated without limitation, the compression head PR1 of the first piston P1 is equipped with a seal J1 on an outer portion which is situated in the vicinity of the inner face of the wall defining the first cylinder CY1, and a second seal J2 on an inner portion which surrounds the first hole T1 and therefore which is located in the vicinity of the outer face of the wall defining the second cylinder CY2.

Moreover, in order to avoid fluid leaks, out of the second chamber CH2, it is advantageous, as illustrated in FIGS. 1 and 5, for the compression head PR2 of the second piston P2 to be equipped with a gasket. sealing J3, for example toric type. This seal J3 is secured to an outer portion of the compression head PR2 which is located in the vicinity of the inner face of the wall defining the second cylinder CY2.

It will be noted, as shown in non-limiting manner in FIG. 1, that the control device DC may comprise a first spring R1 installed in its first chamber CH1 around the second cylinder CY2 upstream of the first piston P1, on the opposite side to the first shaft A1. In this configuration, the first spring R1 is intended to induce a pre-charge of the cup CO. It will be understood that when the first spring R1 is in a rest position, it pushes the first piston P1 forward and therefore the free end PV1 of the first shaft A1 slightly pushes the cup CO, which puts it in pre charge and thus allows to maintain a minimal effort on the organ to control. This makes it possible to improve the quality of contact by avoiding any possible play in the control chain, and it is preferentially the organ to be controlled which ensures the return of the piston to its initial position (or rest).

In a variant shown in non-limiting manner in FIG. 2, the control device DC may comprise a first spring R1 installed in the first chamber CH1 around the first shaft A1. In this configuration, the first spring R1 is intended to induce a return of the first piston P1 in a rest position. It will be understood that when the first spring R1 is in a rest position, it pushes the first piston P1 rearward, opposite the cup CO, to ensure its return to an initial position (or rest) .

It will also be noted, as illustrated without limitation in FIG. 1, that the control device DC may comprise a second spring R2 installed in its second chamber CH2 upstream of the second piston P2, on the opposite side to the second shaft A2. In this configuration, the second spring R2 is intended to induce a pre-charge of the cup CO. It will be understood that when the second spring R2 is in a rest position, it pushes the second piston P2 forward and thus the free end PV2 of the second shaft A2 slightly pushes the cup CO, which puts it in preload and thus allows to maintain a minimal effort on the organ to control.

In a variant shown in non-limiting manner in FIG. 2, the control device DC may comprise a second spring R2 installed in the second chamber CH2 around the second shaft A2. In this configuration, the second spring R2 is intended to induce a return of the second piston P2 in a rest position. It will be understood that when the second spring R2 is in a rest position, it pushes the second piston P2 backwards, opposite the cup CO, to ensure its return to an initial position (or rest) .

It will also be noted, as illustrated in FIGS. 1 and 2, that the first chamber CH1 may comprise on the front side (facing the cup CO) an AO ring surrounding the first shaft A1. This ring AO is fixedly secured to the inner face of the wall of the first cylinder CY1, for example by gluing or screwing or clipping. This ring AO may, for example, define a translational stop forward for the compression head PR1 of the first piston P1 (as in the example of Figure 1), or define a front stop for the first spring R1 (as in the example of Figure 2).

An exemplary non-limiting embodiment of such an AO ring is schematically illustrated in FIGS. 6A and 6B. This ring AO may, for example, be made of plastic or metal.

It will also be noted, as illustrated in FIGS. 1 and 2, that the second chamber CH2 is preferentially closed, at a front end which is oriented towards the cup CO, by a bushing DO provided with a hole T3 which is crossed. by the second shaft A2. This bushing DO is fixedly secured to the inner face of the wall of the first cylinder CY2, for example by screwing or clipping. This bushing DO may, for example, define a forward translation stop for the compression head PR2 of the second piston P2 (as in the example of Figure 1), or define a front locking stop for the second spring R2 (as in the example of Figure 2).

An exemplary non-limiting embodiment of such a bushing DO is schematically illustrated in FIGS. 7A and 7B. This socket DO may, for example, be made of plastic or metal.

It will also be noted, as illustrated in FIGS. 1 to 3, that the control device DC may optionally comprise a bellows SP secured to its cup CO and to its body CD, and partly surrounding the first shaft A1. This bellows SP is intended to prevent the entry of dust and / or liquid into the control device DC on the side of its front part.

It should also be noted that the first P1 and second P2 pistons must translate over identical distances (or races). In addition, they must have identical useful sections if they have to work together and at the same time. It is possible to envisage that the first P1 and second P2 pistons have different useful sections, but in this case one must make adaptations according to the races and efforts to be exerted.

The operation of the DC control device is explained below by considering here, by way of purely illustrative example, that only a first control member is intended to simultaneously control the translations of the first P1 and second P2 pistons.

When the first control member is actuated, for example by a pressure of a foot of a conductor, it induces a fluid inlet in the first channel CA1 via a first input E1 of the latter (CA1), and an input of fluid in the second channel CA2 via a second input E2 of the latter (CA2).

These incoming fluids penetrate respectively into the first CH1 and second CH2 chambers, and thus cause forward translations of the first P1 and second P2 pistons. These translations are proportional to the quantities of fluid entered in the first CA1 and second CA2 channels. The free ends PV1 and PV2 of the first A1 and second A2 trees then push forward the cup CO, which will then induce an action on the body to be controlled, proportional to the translations.

When the first control member is no longer actuated, for example due to the absence of pressure exerted by the driver's foot, this allows the fluid previously entered in the first channel CA1 to emerge from the latter (CA1) via its first input E1, and fluid previously entered in the second channel CA2 out of the latter (CA2) via its second input E2. This results in a reduction of the pressure exerted on the first P1 and second P2 pistons, and thus rearward translations of the latter (P1 and P2), into their rest positions (or initials), under the action respectively the first R1 and second R2 springs and / or the CO cup repelled by the body to control.

When the first control member is actuated, for example by a pressure of a foot of a conductor but there is a sealing problem and / or piston in a chamber (for example the first CH1), it induces always a fluid inlet in the first channel CA1 via a first input E1 thereof (CA1), and a fluid inlet in the second channel CA2 via a second input E2 of the latter (CA2).

These incoming fluids always enter the first CH1 and second CH2 chambers, respectively, but this causes only a correct translation towards the front of the second piston P2. This translation is proportional to the quantity of fluid entering the second channel CA2. Only the free end PV2 of the second shaft A2 then pushes forward the cup CO, which will then induce an action on the body to be controlled, proportional to the translation.

A similar operation occurs in case of sealing problem and / or piston in the second chamber CH2 (but in this case it is the first piston P1 which is translated and displaces only the cup CO). The invention offers several advantages, among which: a guarantee and a securing of the operation of the organ to be controlled, without any significant increase in the bulk, the possibility of having two independent fluid feeds which can be controlled at night by the same control organ, either by two control organs, - the use of two independent pistons that can work either together and at the same time, or individually (one piston acting, the other remaining waiting), or again one after the other, - adaptability to many organs to control and many control organs.

Claims (10)

1. Device (DC) for controlling an organ to be tested, said device (DC) comprising a body (CD) comprising a first cylinder (CY1) comprising a first chamber (CH1) communicating with a first channel (CA1), in which circulates a fluid under the control of at least a first control member, and translational housing a first piston (P1) having a first shaft (A1) adapted to translate a cup (CO) intended to act on said body to be controlled , characterized in that said body (CD) comprises a second cylinder (CY2), housed in said first chamber (CH1) and partly in an open housing (LO) defined in said first piston (P1), and comprising a second chamber (CH2) communicating with a second channel (CA2), in which a fluid flows under the control of said first control member and / or a second control member, and translational housing a second piston (P2) having a second shaft (A2) housed partly in said lodge nt open (LO) and able to translate said cup (CO). 2. Device according to claim 1, characterized in that it comprises a first spring (R1) installed in said first chamber (CH1) around said second cylinder (CY2) upstream of said first piston (P1), the opposite side to said first shaft (A1), to induce a pre-charge of said cup (CO). 3. Device according to claim 1, characterized in that it comprises a first spring (R1) installed in said first chamber (CH1) around said first shaft (A1) to induce a return of said first piston (P1) in a rest position. 4. Device according to one of claims 1 to 3, characterized in that it comprises a second spring (R2) installed in said second chamber (CH2) upstream of said second piston (P2), on the opposite side to said second shaft ( A2), in order to induce a pre-charge of said cup (CO). 5. Device according to one of claims 1 to 3, characterized in that it comprises a second spring (R2) installed in said second chamber (CH2) around said second shaft (A2) to induce a return of said second piston (P2) in a rest position. 6. Device according to one of claims 1 to 5, characterized in that it comprises a bellows (SP) secured to said cup (CO) and said body (CD), and partially surrounding said first shaft (A1). 7. Device according to one of claims 1 to 6, characterized in that said first chamber (CH1) comprises on the side of said cup (CO) a ring (AO) surrounding said first shaft (A1) and defining a stop. 8. Device according to one of claims 1 to 7, characterized in that said second chamber (CH2) is closed at one end facing said cup (CO) by a bushing (DO) provided with a through hole by said second shaft (A2) and defining a stop. 9. Vehicle comprising at least one control member and at least one first control member for controlling said control member, characterized in that it further comprises at least one control device (DC) according to one of the claims. preceding. 10. Vehicle according to claim 9, characterized in that said member to be controlled is selected from a group comprising a brake pad, a clutch fork and a wheel pivot member.