Brake system damping device with passageway

Abstract

To provide a device for vibration damping in a brake system with improved damping properties.SOLUTION: A brake system damping device (10) includes: a third chamber (28) in which a compressible medium is located; and a second separating element (26) separating a second chamber (24) from the third chamber (28). The second chamber (24) is connected to the third chamber (28) in a medium-conducting manner by a passage (50) formed in the second separating element (26). A closing element (34) is moved by a first separating element (22), and as soon as the hydraulic pressure in a first chamber (20) reaches a predefined pressure value, the passage (50) is closed in a movement direction by the closing element (34).SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The invention relates to a brake system damping device having a first chamber to which a hydraulic pressure is to be applied and a second chamber in which a compressible medium is present. A first separating element is used to separate the first chamber from the second chamber. The brake system damping device further comprises a third chamber in which a compressible medium is present and a second separating element for separating the second chamber from the third chamber. The second chamber is connected to the third chamber in a medium-guiding manner by a passage formed in the second separating element, and the first separating element causes a movement of a closing element such that the passage is closed by the closing element in the direction of movement as soon as the hydraulic pressure reaches a predefined pressure value in the first chamber. [Background technology]

[0002] Brake systems, in particular hydraulic brake systems, are used to slow down the travelling speed of vehicles, for example cars and trucks. During operation of such brake systems, various dynamic effects, in particular pressure fluctuations, occur in the lines and chambers present in the brake system, which cause vibrations or pulsations, thereby causing undesirable noise and vibrations. In order to reduce such vibrations or to obtain a damping effect in the event of such vibrations, a brake system damping device, also referred to as a damper in the following, is mounted at one or more mounting points in the brake system. The damper has a first chamber, into which hydraulic pressure is applied. The chamber is essentially a type of container. The pressure is essentially the result of forces acting on a surface. In the damper, the forces are transmitted hydraulically, i.e. via a liquid under pressure.

[0003] Dampers are known that have a separating element which separates a chamber into a first chamber in which a liquid or fluid is present and a second chamber in which a compressible medium, usually in the form of a gas, is present. When an externally increased pressure acts on this container, the volume of the chamber of the deformable container, in which the gas is present, is known to decrease. Similarly, when a liquid pressure is applied to the first chamber, the separating element causes the volume of the second chamber to decrease.

[0004] If this pressure drops again, the volume of gas and therefore the volume of the second chamber will increase accordingly again. The second chamber thus acts like a pneumatic spring, also called a gas spring. How softly or hardly this gas spring damps depends on the gas volume in the second chamber. The larger the gas volume, the softer the damping.

[0005] When braking, the driver depresses the brake pedal, which then travels through a pedal stroke. The pedal stroke is directly related to the gas volume in the second chamber that is optimal here. The larger the gas volume, the longer the pedal stroke. The positive effects of soft damping are therefore opposed to the negative effects of a large pedal stroke length.

[0006] The third chamber, like the second chamber, receives a compressible medium, which is preferably formed by a gas and particularly preferably by air. The second separating element separates the third chamber from the second chamber, the two chambers being connected first by a passage through which the medium can be guided. The passage or the connection is preferably formed by a simple hole and can be closed by a closing element of the first separating element. In a preferred embodiment, the closing element is simply a surface area on the surface of the first separating element. The closing element closes the passage only when sufficient hydraulic pressure for this purpose is applied in the first chamber. In particular, the first separating element is deformed, in particular from a predefined pressure value, until the first separating element abuts against the second separating element. The second separating element thus preferably forms a stop for the closing element.

[0007] Due to the closed passage, the third chamber is blocked off from the second chamber and is therefore no longer provided for the remaining damping. A medium volume still remains in the second chamber for further damping action above the predefined pressure value. This medium volume is relatively small due to the first separating element being deformed in the direction of the second separating element. The damper according to the invention therefore has a relatively weak elastic and damping action, since the second chamber can hardly accommodate the volume. In this case, the effect is that the stroke or pedal stroke of the brake pedal of the brake system is no longer significantly extended when actuated by the vehicle driver.

[0008] When the passage is closed, the first separating element, including the side of the second separating element facing the second chamber, completely abuts against the inner wall of the second chamber, so that the second chamber completely disappears or no longer has a volume. The pedal stroke does not extend any further than the predefined pressure value. This also confirms the disappearance of the damping effect, since the optimal pressure range for damping is below the predefined pressure value.

[0009] The pressure value is preferably selected or predefined so as to constitute the upper limit of an optimal pressure range for damping. In this case, the respective volumes of the second and third chambers are preferably adapted to the optimal pressure range and the desired elasticity or damping effect of the damper. In a preferred manner, the damper combines a high elasticity of a large medium volume in the optimal pressure range for damping with the limit of the volume that can be accommodated by the first chamber, which is above this pressure range. In other words, there is no longer a direct relationship between the medium volume used for damping and the displaced volume of brake medium. The damper therefore provides excellent damping properties at short pedal strokes.

[0010] Another advantage is that the pressure in the closed third chamber is significantly lower than in the second chamber without a passage to the other chamber as in the prior art, which reduces the adverse effects: on the one hand, the permeation through the first separating element is reduced at low pressure, and on the other hand, the temperature of the medium is not so high at lower pressure, so that the material deterioration of the first separating element is delayed. Summary of the Invention [Problem to be solved by the invention]

[0011] SUMMARY OF THE DISCLOSURE It is an object of the present invention to provide a device for vibration damping in a brake system which has improved damping properties. [Means for solving the problem]

[0012] According to the invention, a brake system damping device is provided, which comprises a first chamber to which a hydraulic pressure is to be applied, a second chamber in which a compressible medium is present, and a first separating element for separating the first chamber from the second chamber. The brake system damping device according to the invention further comprises a third chamber in which a compressible medium is present, and a second separating element for separating the second chamber from the third chamber, in which the second chamber is connected to the third chamber in a media-guiding manner by a passage formed in the second separating element, and the first separating element causes a movement of a closing element such that the closing element closes the passage in the direction of movement as soon as the hydraulic pressure in the first chamber reaches a predefined pressure value. According to the invention, the passage is configured with at least one passage opening on its side facing the second chamber, the cross section of the passage opening being aligned approximately in the direction of movement of the closing element. Effect of the Invention

[0013] According to the invention, the cross section of at least one passage opening does not extend transversely to the direction of movement of the closing element closing this passage opening, as is usually the case, but rather extends approximately in this direction of movement, i.e. the cross section extends in the direction in which the closing element also moves. The closing element therefore does not directly abut against the edge of the passage opening, and the closing element itself cannot penetrate into the passage opening. The closing element therefore does not fix itself in the passage opening or wedges into it. Instead, the closing element covers the passage opening entirely or to a large extent and abuts against abutment areas further away from the passage opening. This reliably prevents the closing element from wedging or sticking to the passage opening and the associated passage, while at the same time providing high operational reliability in a very cost-effective manner.

[0014] At least one passage opening is preferably configured as a slit. A slit is understood in this case to mean an opening surface having a relatively long slit length (in particular 1 millimeter and more) and a relatively small slit width (in particular less than 1 millimeter). In such a slit, the slit width preferably extends in the direction of movement of the closing element. Such a passage opening can therefore be opened and closed with a relatively small movement of the closing element. At the same time, a relatively long slit length provides a relatively large cross section with low flow resistance.

[0015] Preferably, two to four, in particular three, passage openings are provided, which are preferably distributed over the cylindrical circumferential wall. A plurality of, in particular an odd number of, passage openings results in an irregular flow through the passage and thus in a flow through the passage according to the invention with low pressure impulses and pressure fluctuations.

[0016] The channel according to the invention is further preferably covered on its side facing the second chamber by a convex cap, which provides a pin-shaped abutment surface for the first separating element, against which the first separating element is supported without blocking at least one associated channel opening. The convex shape of the cap simultaneously serves to ensure that the first separating element can abut against the cap without shoulders or bent edges and thus without creases.

[0017] According to a preferred embodiment, the second separating element is produced by injection molding, preferably by powder injection molding, particularly preferably by metal powder injection molding. Injection molding, also called die casting or die casting method, is a manufacturing method, more precisely a molding method, for producing components. In this case, the respective material is liquefied and injected under pressure into a mold by an injection molding machine. Powder injection molding, also called PIM method (English: Powder Injection Moulding), is a molding method for producing components made of metal or ceramic. Metal powder injection molding, also called MIM method (English: Metal Injection Moulding), is therefore a molding method, in particular for producing components made of metal. By means of such a technique, the second separating element or the diaphragm carrier structure can be produced as a geometrically defined component very simply and inexpensively.

[0018] In a preferred embodiment, the passage is further formed on the side opposite the second chamber by a central passage, which can be configured very conveniently as a central element in an injection mold, particularly when the second separation element is produced by means of an injection molding tool or an injection mold. Furthermore, a passage of this type can be dimensioned relatively simply as a central passage.

[0019] The second separating element can be produced particularly simply by being produced by injection molding in an injection molding tool having a lower tool half and an upper tool half, and by producing at least one passage opening as a boundary surface between the lower tool half and the upper tool half, in such a way that a special core in the injection molding tool can be dispensed with.

[0020] In a preferred embodiment, the brake system damping device has a support structure, in particular in the form of a rib structure, which supports the second separating element and passes through the third chamber. A support structure of this type in particular has a structure end side and at least one structure rib. In this case, the rib structure is arranged in a preferred manner on the second separating element on the side opposite the first separating element or on the side with the separating element outer wall in order to support the second separating element against pressure acting on the separating element inner wall. The separating element outer wall thereby forms the first end side of the rib structure. The opposite end side or the second end side of the rib structure is formed by the structure end side, which is preferably configured in a planar manner. The structure rib is a supporting element of the rib structure which has a supporting effect and extends from the separating element outer wall to the structure end side. Due to the supporting function of the rib structure, the brake system damping device is itself relatively robust. Moreover, the material of the second separating element is not subjected to much abuse, which has a positive effect on the service life of the second separating element.

[0021] Preferably, in order to provide the rib structure with additional stability, the rib structure is configured with two or more structural ribs. Moreover, the rib structure is preferably configured with a vertical circular hollow cylinder, which abuts with its center against the outer wall of the separating element and extends from the outer wall of the separating element to the second end or the structural end side of the rib structure. In this case, the cylindrical cavity formed in the circular hollow cylinder is preferably connected to the passage in the second separating element in a medium-guiding manner. It is to be clearly pointed out here that the passage in the second separating element must never be closed by the rib structure.

[0022] The structural ribs rest against the outside of the circular hollow cylinder, and here have a size or rib depth that corresponds to the length of the circular hollow cylinder, hereinafter referred to as the abutment point. From this abutment point, the structural ribs preferably extend radially or radially away from the circular hollow cylinder, thereby forming a star-shaped structure. In this case, the rib depth of each structural rib varies according to the shape of the abutting end side of the rib structure. As mentioned above, the structural end side is preferably planar and therefore does not result in a change in the rib depth. In contrast, the outer wall of the separating element is usually designed non-flat or three-dimensionally. Therefore, the respective rib depth must vary or be designed according to the outer wall of the separating element. This further improves the stability of the rib structure.

[0023] In a preferred embodiment, the rib structure forms at least two structural chambers, which are connected to one another in a medium-guiding manner by at least one connecting passage. In this case, each structural chamber is composed of at least one structural rib, the outer wall of the separating element and a further component surrounding the third chamber. These components are preferably covers. In this case, the structural chambers are preferably formed with a supporting rib structure or are arranged in such a way that the supporting effect of the rib structure is further increased. The connecting passage is an opening in the component, preferably in a structural rib separating the two support chambers from one another. In this way, the compressible medium reaches the respective structural chambers of the divided third chamber from the second chamber, thereby providing maximum damping effect for the brake system damping device. Moreover, a lower damping rate can be set, if required, by separating the individual structural chambers or by closing the individual connecting passages.

[0024] If the rib structure with a circular hollow cylinder is constructed as described above for the preferred embodiment, each of the structure's partial chambers preferably has a connecting passage leading from this cylindrical hollow chamber, in this way a uniform distribution of the medium and thus the same strength of loading of all areas of the rib structure is obtained.

[0025] According to a next preferred development of the invention, the first separating element is configured with a diaphragm, preferably a rolling element diaphragm. The diaphragm can essentially be understood here as a sealing element, which as an elastically movable separating wall or separating element separates two chambers from each other in a gas-tight manner. In this case, the rolling element diaphragm is provided specifically only for one-sided pressure loading in the direction towards the inside of the loop or towards the diaphragm head recess. The volume change of the rolling element diaphragm is opposed only by a negligibly low inherent stiffness or a low resistance to elastic deformation. Due to its shaping, the rolling element diaphragm is particularly well suited as a separating element for the brake system damping device according to the invention.

[0026] Preferably, the first separating element is made of an elastomer, preferably ethylene propylene diene rubber. Elastomers are shape-stable but elastically deformable plastics. Such plastics are therefore deformed under tensile and compressive loads, but then return to their initial, undeformed form. Elastomers are therefore particularly well-suited materials for separating elements in the sense of the present invention, such as rolling element diaphragms as described above.

[0027] The elastomer must maintain its elasticity and not be allowed to expand or contract excessively. Therefore, an appropriate elastomer must be used for the medium to be sealed. Ethylene propylene diene rubber, also called EPDM for short, is an elastomer that is resistant to braking media and is therefore particularly suitable for use in the brake system damping device according to the present invention.

[0028] Moreover, according to the invention, the predefined pressure value is preferably predefined to a value between 0 and 30 bar, preferably in the range between 3 and 10 bar, particularly preferably to 5 bar. If the brake system applies a pressure of approximately 60 bar to the associated wheel of the vehicle, this will definitely cause the wheel to lock. However, for vibration or pulsation damping in the brake system, only a very small, limited pressure range is important. At an obtained pressure value of approximately 5 bar, the disruptive vibrations or pulsations are already sufficiently damped. Therefore, the pressure value must be predefined to this value in a particularly preferred manner.

[0029] Furthermore, the passage is preferably made of an open-cell material. Open-cell refers to a material containing multiple pores that prevent fluid from entering but allow gas to escape or penetrate. It can also refer to a breathable material. The multiple pores will be closed after the abutment of the first separating element, as well as passages of different configurations, such as multiple holes. The advantage of an open-cell material is that fluid cannot enter the third chamber. This brake system has additional protection against the escape of brake fluid from the brake system, for example if the first separating element is damaged or not airtight.

[0030] Furthermore, a number of passages are provided in a suitable manner in the second separating element in order to more quickly redistribute the medium from the second chamber to the third chamber during the braking process, so that the elasticity of the entire medium volume can be better utilized.

[0031] Additionally, other embodiments are preferred which make the brake system damping device more effective or which supplement the brake system with optional embodiments.

[0032] In another preferred embodiment, the third chamber is divided into several partial chambers, each of which is connected to the second chamber in a medium-guiding manner by a passage. Several partial chambers allow greater flexibility than using only one separate third chamber. The passages leading to the separate partial chambers are thus closed one after the other in a preferred manner by the first separating element, so that the damping effect is reduced stepwise and not completely and abruptly at a predefined pressure value. Moreover, due to the closing and reusability of several passages, a variable number of partial chambers and thus a variable medium volume are available. This makes it easier to adapt the damper to the optimum pressure range and the desired elasticity.

[0033] The compressible medium received in the second and third chambers is therefore preferably configured as a gas, and particularly preferably as air, which is inexpensive and easy to provide, is compressible and is therefore particularly suitable for use in the brake system damping device according to the invention.

[0034] The medium volume or the second and third chambers are produced or obtained, optionally and in a preferred manner, by the combination of a plurality of turned, cold forged or deep drawn parts. The turned parts are components with a circular cross section, the cold forged parts are closed components and the deep drawn parts are body components of the car. All these components are easily available in the car industry and can find new applications thanks to the present invention.

[0035] Furthermore, the brake system damping device is preferably provided for use in vehicle dynamics control and / or powered braking systems. Electronic stability programs, also called vehicle dynamics control or ESP, are electronically controlled drive assistance systems for motor vehicles that counteract vehicle slip by targeted braking of individual wheels. Powered braking systems or powered brake devices are actuated by externally generated forces. For example, electrohydraulically actuated brakes are powered brakes, in which the actuating energy is obtained from a hydraulic accumulator loaded by a pump. [Brief description of the drawings]

[0036] [Figure 1] FIG. 1 shows a first example of a brake system damping device forming the basis of the present invention; [Diagram 2] 2 illustrates the brake system damping device shown in FIG. 1 at a first applied hydraulic pressure. [Diagram 3] 2 illustrates the brake system damping device shown in FIG. 1 at a second applied hydraulic pressure. [Figure 4]2 is a diagram having characteristic curves showing the relationship between volume acceptance and pressure within a brake system damping device. [Diagram 5] FIG. 1 shows a second example of such a brake system damping device. [Figure 6] FIG. 11 shows a third example of such a brake system damping device. [Figure 7] FIG. 7 is a view VII of the separation element of the brake system damping device shown in FIG. 6 . [Figure 8] 1 is a perspective view of one embodiment of a separation element of a brake system damping device according to the present invention; [Figure 9] FIG. 9 is a cross-sectional view taken along line IX-IX in FIG. [Figure 10] FIG. 10 shows detail X of FIG. [Figure 11] 10 is a cross-sectional view taken along line XI-XI in FIG. 8. [Figure 12] 10 is a cross-sectional view taken along line XII-XII in FIG. 8. [Figure 13] FIG. 13 shows detail XIII of FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0037] In the following, an embodiment of the solution according to the invention is explained in detail with the aid of the attached schematic drawings.

[0038] In Fig. 1, a brake system damping device 10 is shown with a housing 12 and a cover 14. A supply line 16 is arranged in the housing 12, in which no hydraulic pressure is applied, as indicated here by the crossed arrow 18. The supply line 16 opens into a first chamber 20, which is followed by a first separating element 22, here a rolling body diaphragm. Behind the first separating element 22, as viewed from the first chamber 20, is a second chamber 24, which is followed by a second separating element 26, in which case a third chamber 28 is located behind the second separating element 26 in the direction of observation.

[0039] The chambers 20, 24, 28 and the separating elements 22, 26 are described in more detail below. The first chamber 20 is surrounded by a housing inner wall 30 and a first separating element inner wall 32 of the first separating element 22, which is referred to below as the rolling element diaphragm. A closing element 34 is arranged in the center of the separating element 22, which is configured in one piece with the separating element 22, from which the separating element 22 runs further outwards to a diaphragm fold 36. A diaphragm fold recess 38 is located within or surrounded by the diaphragm fold 36. Following the diaphragm fold 36, the separating element 22 extends up to a diaphragm flange 40, which grips a connecting frame 42 of the housing 12. The separating element 22, configured as a rolling element diaphragm, rests closely against the housing inner wall 30 with its separating element inner wall 32 and has a first separating element outer wall 44 facing the second chamber 24. The second chamber 24 is surrounded by the first separating element outer wall 44 and by a second separating element inner wall 46 of the second separating element 26.

[0040] The second separating element 26 extends into the diaphragm fold recess 38 with a diaphragm retaining device 48. A passage 50 is arranged in the center of the second separating element 26, which passage 50 connects the second chamber 24 with the third chamber 28. In this case, the passage 50 extends through the second separating element inner wall 46, the second separating element 26 and the second separating element outer wall 52. The third chamber 28 is surrounded by the second separating element outer wall 52 and the cover inner wall 54 of the cover 14.

[0041] In the illustrated initial state of the brake system damping device 10, no hydraulic pressure 18 is yet applied in the first chamber 20, in which the brake medium is present. The separating element 22 made of elastomer essentially retains its basic shape. In this case, the separating element 22 rests against the housing inner wall 30, in such a way that the first chamber 20 is sealed gas-tight with respect to the second chamber 24, in which a gas, here air, is present. This gas is also present in the third chamber 28, which is connected to the second chamber 24 by a passage 50. These two chambers 24, 28 thus form a common gas volume which can be provided for damping. Due to the relatively strong elasticity of this gas volume, a better damping effect is obtained during braking or when hydraulic pressure is applied to the first chamber 20.

[0042] When hydraulic pressure is applied in the first chamber 20, the separating element 22 is deformed such that the gas volume in the second chamber 24 is reduced. In this case, the closing element 34 moves into the second chamber 24. From a certain hydraulic pressure defined above the optimum pressure range for damping, the closing element 34 abuts against the second separating element inner wall 46 of the second separating element 26 and closes the passage 50 leading to the third chamber 28. In this case, the second separating element 26 acts like a stopper. The state of the brake system damping device 10 in which the separating element 22 or its closing element 34 abuts against the second separating element 26 and closes the passage 50 is shown in Figs. 2 and 3.

[0043] Due to the closed passage 50, the third chamber 28 is separated from the second chamber 24, so that only the gas volume remaining in the second chamber 24 can be used for further damping. Since the second chamber 24 can barely accommodate any volume, it only has a small elastic and damping effect. This effect is desired, because it also prevents the stroke of the brake pedal connected to the brake system from being significantly extended any further. In the state of the brake system damping device 10 shown in FIG. 3, the separating element 22 and the second separating element 26 abut against each other without a gap or all over, so that the second chamber 24 disappears completely or no longer has a volume. In this case, the stroke of the brake pedal is no longer extended.

[0044] As soon as the hydraulic pressure applied in the first chamber 20 is reduced, the separating element 22 returns again to its initial state or position.

[0045] FIG. 2 shows the brake system damping device 10 of FIG. 1 with a first hydraulic pressure applied to the first chamber 20 , as indicated by arrow 56 in the area of ​​the supply line 16 .

[0046] As mentioned above, in this case the closing element 34 abuts against the second separating element inner wall 46 of the second separating element 26 and closes the passage 50 leading to the third chamber 28. As a result, only the volume still remaining in the second chamber 24 is available for further damping. In FIG. 2, essentially only the area around the diaphragm retaining device 48 is shown. The influence on damping and braking operation has already been explained in detail in the specification in connection with FIG. 1 and will not be explained again here.

[0047] FIG. 3 illustrates the brake system damping device 10 shown in FIG. 1 with a second hydraulic pressure applied to the first chamber 20, as indicated by arrow 58 within the supply line 16.

[0048] As mentioned above, in this case the closing element 34 abuts against the second separating element inner wall 46 of the second separating element 26 and closes the passage 50 leading to the third chamber 28. Furthermore, the separating element 22 and the second separating element 26 abut against one another without a gap, so that the second chamber 24 no longer has a volume. The associated influence on damping and braking action has already been explained in detail in the specification in connection with FIG. 1 and will not be described again here.

[0049] 4 shows a diagram of the relationship between pressure 60 and volume acceptance 62 in such a type of brake system damping device, with pressure 60 plotted on the x-axis and volume acceptance 62 plotted on the y-axis. From the coordinate origin of the diagram extend a first characteristic curve 64 and a second characteristic curve 66. Furthermore, the diagram shows a vertical dashed line 68 intersecting the x-axis and a horizontal dashed line 70 intersecting the y-axis.

[0050] A first characteristic curve 64 shows the relationship between volume acceptance and pressure for a brake system damping device having a small volume of medium provided for damping, for which the volume of the second chamber 24 of FIG.

[0051] In contrast, a second characteristic curve 66 extending above the first characteristic curve 64 shows the relationship between volume acceptance and pressure for a brake system damping device 10 having a relatively large volume of medium provided for damping. Here, for the purpose of the characteristic curve 66, the combined volumes of the second and third chambers 24, 28 of FIG. 1 are shown in a simplified form.

[0052] A predefined pressure value 68 is indicated by a vertical dashed line intersecting the x-axis and forming the upper limit of the pressure range associated with pulsation damping of this type of brake system, this optimum pressure range therefore extending from the coordinate origin to the dashed line.

[0053] A volume stop 70 for the brake system damping device 10 of the present invention is indicated by a horizontal dashed line intersecting the y-axis, the volume stop being approximately at the volume of the second chamber 24 in FIG.

[0054] By appropriate design of the respective volumes of the second and third chambers 24, 28, the brake system damping device 10 is adjusted to an optimum pressure range and to the desired elastic or damping effect within this pressure range. As shown in the diagram of FIG. 4, at optimum adjustment, the dashed lines 68, 70 intersect the characteristic curve 66 at one point.

[0055] The brake system damping device 10 shown in Figure 5 differs from that of Figure 1 only in the region of the first separating element 22 configured as a rolling element diaphragm facing the first separating element outer wall 44. The separating element 22 itself and the region facing the separating element 22 with the first separating element inner wall 32 correspond entirely to that of Figure 1 and are therefore not described here anew.

[0056] The main difference with respect to the brake system damping device 10 of Fig. 1 is that instead of the third chamber 28 and the associated passage 50 shown in Fig. 1, the brake system damping device 10 of Fig. 5 has a first partial chamber 72 with a passage 74 and a second partial chamber 76 with a second passage 78. In this case, the two partial chambers 72, 76 are separated by a separating wall 80. A further difference with respect to Fig. 1 is that in Fig. 5 the second separating element 26 extends up to the inner housing wall 30 and the cover 14 is separated from this inner housing wall 30.

[0057] All other features correspond to those of Fig. 1. Thus, the second chamber 24 is again surrounded by the first separating element outer wall 44 and the second separating element inner wall 46 of the second separating element 26. Similarly, the second separating element 26 now has a diaphragm retaining device 48 which extends into the diaphragm fold recess 38 of the separating element 22. Furthermore, the partial chambers 72, 76 adjacent to the separating wall 80 are surrounded by the second separating element outer wall 52 and the cover inner wall 54 of the cover 14, similar to the third chamber 28 of Fig. 1.

[0058] The manner of function here is similar to that of the brake system damping device 10 of Fig. 1. When hydraulic pressure is applied into the first chamber 20, the separating element 22 is also deformed in such a way that the gas volume in the second chamber 24 is reduced. In this case, the closing element 34 moves into the second chamber 24 and comes into abutment against the second separating element 26 from a certain hydraulic pressure, which ideally corresponds to the upper limit of the relevant pressure range, thereby closing the passages 74, 78 to the partial chambers 72, 76.

[0059] As soon as the hydraulic pressure applied in the first chamber 20 is reduced, the separating element 22 configured as a rolling element diaphragm moves back to its initial state or position, whereby the passages 74, 78 are opened again and the partial chambers 72, 76 are again connected with the second chamber 24.

[0060] FIG. 6 shows a brake system damping device 10 which differs from that of FIG. 1 in the alternative cover 14 and in particular in the form of the second separating element 26. The remaining components of FIG. 6 are the same as those of FIG. 1 and are not described again here. However, in the illustrated state of the brake system damping device 10, the first separating element 22 assumes a normal or initial shape, as in FIG. 1, since no hydraulic pressure 18 is applied to the first chamber 20 in the supply line 16. Instead of the cover 14 of FIG. 1, a component 82 with a component outer wall 84 and a component inner wall 86 is used in FIG. 6. This component 82 can here likewise be used as a cover. In this case, the component 82 abuts against the first separating element 22 in such a way that the second separating element 26 is completely surrounded by the component 82 and the first separating element 22. The component inner wall 86 has a recess 88 annularly surrounding the second separating element 26, which recess 88 is here arranged at a maximum distance from the first separating element 22. The component outer wall 84 abuts against the housing 12 or its inner housing wall 30.

[0061] On the side of the separating element inner wall 46, the second separating element 26 is constructed essentially similarly to the second separating element 26 shown in FIG. 1. The only difference is that here the diaphragm retaining device 48 is constructed in the diaphragm fold recess 38 in the form of a trumpet or bulge that widens outwards or in the direction of the housing inner wall 30, and is referred to here as an outer curved section 90. On the side of the separating element outer wall 52, the second separating element 26 has a rib structure 92 that extends from the separating element outer wall 52 to the structure end side 94, thereby penetrating the entire third chamber 28. The rib structure 92 is constructed integrally with the second separating element 26 and is further surrounded by a rib circumferential wall 96 that has a circumferential inner wall 98 and a circumferential outer wall 100. The rib circumferential wall 96 extends from the separating element outer wall 52, precisely from the diaphragm retaining device 48, to the structure end side 94. A plurality of locking elements are disposed on the peripheral outer wall 100 adjacent to the structure end side 94, only locking elements 102 and 104 being visible here, and these locking elements are positioned in a locking manner within the recesses 88.

[0062] A circular hollow cylinder 106 with a cylindrical cavity 108 is arranged in the center of the rib structure 92, which is placed against the outer wall 52 of the separating element in such a way that the passage 50 leads into the cylindrical cavity 108. From the circular hollow cylinder 106 extend a number of structural ribs, of which only the structural ribs 110 and 112 are visible here, which extend to the rib peripheral wall 96 or its inner wall 98. The structural ribs 110, 112 divide the third chamber 28 in the rib peripheral wall 96 into a number of structural sub-chambers, of which only the structural sub-chambers 114, 116 are visible here. The structural sub-chambers are connected to the cylindrical cavity 108 by connecting passages, of which only the connecting passages 118, 120, 122 and 124 are visible here. In this case, the multiple connecting passages 118, 120, 122, 124 are disposed on the structure end side 94.

[0063] The basic function of the brake system damping device 10 shown here can be compared with the brake system damping device 10 of FIG. 1. Here too, for example, the component 82 rests stably against the first separating element 22, like the cover 14 of FIG. 1. In addition, the brake system damping device 10 shown in FIG. 6 has the support function of the rib structure 92, which allows for a stepwise adjustment of the damping rate, as well as the locking of the second separating element 26 in the component 82, here configured as a cover. The support effect is achieved in that all components of the rib structure 92 extend from the separating element outer wall 52 to the structure end side 94, which in this case rests against the structure inner wall 86. The adjustment of the damping rate can be achieved by closing one or more connecting passages 118, 120, 122, 124 leading to the structure part chambers 114, 116. Locking in the component 82 is achieved by means of locking elements 102, 104. When the second separating element 26 is fitted into the component 82 or when the component 82 is fitted over the second separating element 26, the locking elements 102, 104 are pressed inward, i.e. into the rib peripheral wall 96. As soon as the structure end side 94 reaches the component inner wall 86, the locking elements 102, 104 lock into the recesses 88 of the component 82 provided for this purpose.

[0064] 7 shows a perspective view of the second separating element 26 shown in FIG. 6 from the structural end side 94. The rib structure 92 is therefore particularly visible. The outer curved portion 90 and the outer peripheral wall 100 are also clearly visible here. In addition to the structural ribs 110 and 112, further structural ribs 126, 128, 130 and 132 are also shown, which run from the circular hollow cylinder 106 to the rib peripheral wall 96 or to its inner peripheral wall 98. Between the structural ribs 110, 112, 126, 128, 130, 132, structural part chambers 114, 116, 134, 136, 138, 140 are arranged and are connected to the cylindrical hollow chamber 108 by connecting passages 118, 120, 122, 124, 142, 144. In addition to the locking elements 102 and 104, further locking elements 146, 148, 150, 152 are shown in the peripheral outer wall 100 and the structure end side 94. Each of these locking elements 102, 104, 146, 148, 150, 152 is arranged adjacent to two of the peripheral wall slits 154, 156, 158, 160, 162, 164, 166, 168, 170, 172, 174, 176, which extend from the structure end side 94 towards the outer curved portion 90.

[0065] 6, such as the other locking elements 146, 148, 150, 152, have the same functions. Therefore, the function of such components will not be explained anew. Shown entirely anew, and therefore the functionality of which has not yet been explained, are the peripheral wall slits 154, 156, 158, 160, 162, 164, 166, 168, 170, 172, 174, 176. These peripheral wall slits do not only fulfill the purpose of providing additional volume for the third chamber 28. In particular, the peripheral wall slits 154, 156, 158, 160, 162, 164, 166, 168, 170, 172, 174, 176 divide the rib peripheral wall 96, as seen from the structure end side 94, such that the locking elements 102, 104, 146, 148, 150, 152 are separated. Depending on the flexibility of the material of the second separating element 26, the area of ​​the rib circumferential wall 96 in which one of the locking elements 102, 104, 146, 148, 150, 152 is arranged can be pressed more or less easily inwards, which significantly facilitates the assembly of the second separating element 26 and / or the component 82, which is illustrated in FIG.

[0066] 8 to 13 show an embodiment in which the passage 50 as well as the cylindrical cavity 108 disposed downstream in terms of fluidics are designed in a special way in the second separating element 26. In the embodiment shown in FIG.

[0067] In this case, it is provided that the first separating element 22 together with its closing element 34 is displaced in the direction of movement 178 when the second chamber 24 is enlarged and reduced, in particular when the passage 50 is opened and closed. On its side facing the closing element 34, the passage 50 is not configured with a transverse passage opening, the cross section of which is perpendicular to the direction of movement 178, as would be expected, as shown in Figures 1 to 7. Instead, the passage 50 is provided with three passage openings 180, which are individually connected in a fluid-guidable manner by a flow path 182 in each case to the cylindrical hollow chamber 108, which forms a central flow path which further leads to the fluidically downstream third chamber 28, in particular to its structural part chambers 114 and 116.

[0068] The passage openings 180 are each formed with a cross-section 184 which is located in the bottom region of the cup-shaped separation element inner wall 46 under a central convex cap 186 and which is in this case approximately aligned with the movement direction 178 of the closure element 34. In this case, "approximately" is to be understood as meaning that the surface plane of the cross-section 184 extends exactly in the movement direction 178 or at an angle to this movement direction 178 of at least less than 10°, in particular less than 5°.

[0069] In this case, the individual cross sections 184 have the shape of a slit, i.e. have a slit width which is relatively small compared to their slit length. Furthermore, the separating element 26 is preferably produced here by an injection molding process in an injection molding tool with two (not shown) tool halves. In this case, the cross sections 184 are configured as a boundary surface which is formed at the very moment of contact between the upper and lower tool halves. This can be seen clearly in FIG. 13. In this case, the upper tool half is located above or to the side of the cap 186, and the lower tool half projects into the cylindrical chamber or into the central channel 108 and into the channels 182. [Explanation of symbols]

[0070] 10 Brake system damping device 12. Housing 14 Cover 16 Supply line 18 × Marked arrows, hydraulic pressure 20 First Room 22 First separating element, rolling body diaphragm 24 Second Room 26 Second separation element 28 Third Room 30 Housing inner wall 32 first separation element inner wall 34 Closing element 36 Diaphragm fold 38 Diaphragm fold recess 40 Diaphragm flange 42 Combined Frame 44 first separation element outer wall 46 second separation element inner wall 48 Diaphragm Retaining Device 50 Passage 52 second separation element outer wall 54 Cover inner wall 56,58 Arrow 60 Pressure 62 Volume acceptance 64 First characteristic curve 66 Second characteristic curve 68 Pressure Value 70 Horizontal dashed line, volume stop 72 First Partial Room 74 Passage 76 Second Partial Room 78 Second Passage 80 Separation wall 82 Components 84 Component outer wall 86 Component inner wall 88 Recess 90 Outer curve 92 Support structure, rib structure 94 Structure end side 96 Rib Wall 98 Peripheral inner wall 100 Peripheral outer wall 102,104,146,148,150,152 Locking elements 106 Circular hollow cylinder 108 Cylindrical hollow chamber, central flow passage 110,112 Structural rib 114,116 Structure sub-chamber 118,120,122,124 Connecting passages 126,128,130,132 Structural Ribs 146,148,150,152 Locking elements 154,156,158,160,162,164,166,168,170,172,174,176 Peripheral wall slits 178 Direction of motion 180 Passage opening 182 Channel 184 Cross Section 186 Cap

Claims

1. A brake system damping device (10) comprising a first chamber (20) to which a hydraulic pressure is to be applied, a second chamber (24) having a compressible medium therein, and a first separation element (22) for separating the first chamber (20) from the second chamber (24), wherein the brake system damping device (10) comprises a third chamber (28) having a compressible medium therein, and a second separation element (26) for separating the second chamber (24) from the third chamber (28). the second chamber (24) is connected to the third chamber (28) in a medium-guiding manner by a passage (50) formed in the second separating element (26), and the first separating element (22) causes a closing element (34) to move, so that as soon as the hydraulic pressure in the first chamber (20) reaches a predefined pressure value (68), the closing element (34) closes the passage (50) in the direction of movement (178), 2. A brake system damping device comprising: a passage (50) configured with at least one passage opening (180) on its side facing the second chamber (24), the cross section (184) of the passage opening (180) being aligned approximately in the direction of movement (178) of the closure element (34).

2. The brake system damping device of claim 1, wherein at least one of the passage openings (180) is configured as a slit.

3. 3. The brake system damping device of claim 1 or 2, wherein there are two to four of said passage openings (180).

4. 4. The brake system damping device according to claim 1, wherein the passage (50) is covered on its side facing the second chamber (24) by a convex cap (186).

5. 5. The brake system damping device of claim 1, wherein the passage (50) is defined on its side opposite the second chamber (24) by a central flow passage (108).

6. 6. The brake system damping device of claim 1, wherein the second isolation element (26) comprises a support structure (92) extending into the third chamber (28).

7. A brake system damping device as described in any one of claims 1 to 6, characterized in that the first separation element (22) is configured with a diaphragm, preferably a rolling body diaphragm.

8. 8. The damping device for a brake system according to claim 1, wherein the first separating element (22) is made of an elastomer, preferably ethylene propylene diene rubber.

9. A method for manufacturing a brake system damping device (10), comprising: The brake system damping device (10) The pressure sensor includes a first chamber (20) to which a liquid pressure is to be applied, a second chamber (24) in which a compressible medium is present, a first separation element (22) for separating the first chamber (20) from the second chamber (24), a third chamber (28) in which a compressible medium is present, and a second separation element (26) for separating the second chamber (24) from the third chamber (28), the second chamber (24) being connected to the third chamber (28) in a medium-guiding manner by a passage (50) formed in the second separation element (26), and the first separation element (22) a closure element (34) is moved by a pressure member (22) so that as soon as the hydraulic pressure in the first chamber (20) reaches a predefined pressure value (68), said closure element (34) closes said passage (50) in the direction of movement (178), said passage (50) being configured with at least one passage opening (180) on its side facing the second chamber (24), the cross section (184) of said passage opening (180) being aligned approximately in said direction of movement (178) of said closure element (34), 4. A method for producing a separator according to claim 3, wherein the second separating element (26) is produced by injection molding in an injection molding tool having a lower tool half and an upper tool half, and wherein at least one of the passage openings (180) is produced as an interface between the lower tool half and the upper tool half.

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