Master brake cylinder for a vehicle's braking system and manufacturing process for a master brake cylinder

Abstract

Master brake cylinder (10) for a braking system of a vehicle with: a first pressure chamber (18), wherein a first rod piston component (20) is adjustable into at least a first partial pressure chamber (22) of the first pressure chamber (18) such that a first partial residual volume of the first partial pressure chamber (22) that can be filled with liquid can be reduced by adjusting the first rod piston component (20); characterized by a second partial pressure chamber (24) of the first pressure chamber (18), which is separated from the first partial pressure chamber (22) by at least a partial partition (28), and into which a second rod piston component (26) can be adjusted such that a second residual volume of the second partial pressure chamber (24) which can be filled with liquid can be reduced by adjusting the second rod piston component (26), wherein the master brake cylinder (10) comprises the first rod piston component (20) and the second rod piston component (26), and wherein the second rod piston component (26) has a continuous recess into which at least a part of the first rod piston component (20) projects adjustably.

Description

[0001] The invention relates to a master brake cylinder for a vehicle's braking system. The invention also relates to a brake unit for a vehicle's braking system and a braking system for a vehicle. Furthermore, the invention relates to a manufacturing method for a master brake cylinder, a manufacturing method for a brake unit, and a manufacturing method for a braking system. State of the art

[0002] German patent application DE 10 2009 055 117 A1 describes a master brake cylinder for a hydraulic vehicle braking system and a method for its operation. The master brake cylinder has a rod piston, designated as the first piston, and a tubular second piston. The first piston can be pushed through the second piston into a first pressure chamber of the master brake cylinder by a predetermined piston stroke. A drive mechanism formed on the second piston is intended to cause the first piston to drive the second piston along with it after overcoming the predetermined piston stroke. After overcoming the predetermined piston stroke, the first and second pistons should be able to act together on the first pressure chamber of the master brake cylinder. Additionally, a floating piston should allow the cylinder to act on a second pressure chamber of the master brake cylinder.

[0003] A dual-circuit brake control system is known from US 4 505 116 A.

[0004] DE 10 2006 036 311 A1 discloses a brake force generator for a hydraulic motor vehicle brake system and a motor vehicle brake system.

[0005] The US 2002 / 0 063 4 70 A1 shows a hydraulic brake device. Disclosure of the invention

[0006] The invention provides a master brake cylinder for a vehicle braking system with the features of claim 1, a brake device for a vehicle braking system with the features of claim 8, a brake system for a vehicle with the features of claim 11, a manufacturing method for a master brake cylinder with the features of claim 12, a manufacturing method for a brake device with the features of claim 13 and a manufacturing method for a brake system with the features of claim 14.

[0007] The first rod piston component and / or the second rod piston component can be a rod piston and / or a primary piston. However, it should be noted that the first rod piston component and the second rod piston component are not limited to being designed as rod pistons. In particular, the design of the first rod piston component and / or the second rod piston component is not limited to a specific type of rod piston.

[0008] Furthermore, the first rod-piston component and / or the second rod-piston component can also be designed as contact parts for a rod piston each. In this case, the first rod-piston component and / or the second rod-piston component can also be described as pistons interacting with the respective rod piston, which limit the residual volume assigned to them.

[0009] The first rod piston component and / or the second rod piston component can be formed as a single piece. Likewise, the first rod piston component and / or the second rod piston component can also be composed of several assembled subunits. The use of the term "component" does not restrict the formability of the first rod piston component and / or the second rod piston component to a single-piece design.

[0010] It is noted that the claimed master brake cylinder is not limited to being equipped with the first rod piston assembly and the second rod piston assembly. Instead, the master brake cylinder can also be designed to interact with at least two rod piston assemblies without these being considered part of the master brake cylinder. Advantages of the invention

[0011] The present invention provides for the separation / subdivision of a rod-type piston component (primary piston) adjustable into a pressure chamber of the master brake cylinder into different segments / piston / pin components. This separation enables staged brake force amplification. In particular, the contact area within the master brake cylinder can be varied in this way.

[0012] Furthermore, the present invention provides for the separation / subdivision of the first pressure chamber of the master brake cylinder into at least two mutually distinguishable partial pressure chambers. This also results in a staged brake force amplification. As explained in more detail below, the staged brake force amplification allows for better compensation of any functional impairment of the brake force amplification.

[0013] Preferably, the term "first pressure chamber" refers to a pressure chamber assembly comprising at least the first partial pressure chamber and the second partial pressure chamber, in which fluid exchange between the first partial pressure chamber and the second partial pressure chamber is ensured in at least one operating mode of the first pressure chamber. This can also be described as a hydraulic connection existing in at least one operating mode of the first pressure chamber, which results in a common internal pressure in the at least two partial pressure chambers of the first pressure chamber.

[0014] In an advantageous embodiment, the second partial pressure chamber is separated from the first partial pressure chamber by a partition wall with at least one continuous flow opening, such that a common internal pressure of the first and second partial pressure chambers exists within the first pressure chamber, which comprises at least the first and second partial pressure chambers. Setting a common internal pressure in the first and second partial pressure chambers is easily achieved via the at least one continuous flow opening.

[0015] Alternatively, the second partial pressure chamber can be separated from the first partial pressure chamber by a partition wall without openings, and the first partial pressure chamber can be hydraulically connected to the second partial pressure chamber via an externally routed line such that the common internal pressure of the first and second partial pressure chambers is present in the first pressure chamber, which comprises at least the first and second partial pressure chambers. In this case as well, if the externally routed line is open to flow, an automatic pressure equalization between the first and second partial pressure chambers occurs.

[0016] In a further advantageous embodiment, the master brake cylinder comprises a second pressure chamber into which a floating piston component projects such that the residual volume of the second pressure chamber, which can be filled with fluid, can be varied by adjusting the floating piston component. Thus, the present invention can also be extended to a tandem master brake cylinder. The present invention is therefore applicable to a multitude of differently designed multi-circuit brake systems.

[0017] According to the invention, the master brake cylinder comprises the first rod-piston component and the second rod-piston component, wherein the second rod-piston component has a continuous recess into which at least a part of the first rod-piston component adjustably projects. As explained in more detail below, such a design of the two rod-piston components ensures a uniform pressure and force distribution when the two rod-piston components are inserted into the first pressure chamber of the master brake cylinder.

[0018] Similarly, the second partial pressure chamber can be rotationally symmetrical to the central longitudinal axis of the first partial pressure chamber. In this case as well, an advantageous pressure and force distribution is ensured when both rod piston components are simultaneously inserted into the first pressure chamber.

[0019] As an addition, the master brake cylinder can comprise a third partial pressure chamber of the first pressure chamber, which is separated from the first partial pressure chamber and / or the second partial pressure chamber by at least one further partial partition, and into which a third rod piston component can be adjusted such that a third residual volume of the third partial pressure chamber, which can be filled with fluid, can be reduced by adjusting the third rod piston component. Thus, a three-stage or more-stage brake force amplification is also possible with the present invention.

[0020] Preferably, the third partial pressure chamber can be designed to be mirror-symmetrical to the second partial pressure chamber with respect to a plane of symmetry that intersects the first partial pressure chamber at its center. In this way, even when three rod-piston components are simultaneously inserted into the first pressure chamber, an advantageous pressure and force distribution is ensured despite the pressure opposing the insertion.

[0021] The advantages described in the paragraphs above are also achieved with a corresponding braking device for a vehicle's braking system.

[0022] In an advantageous embodiment, the brake device comprises an amplifier body of the brake force booster device, on which a brake support force can be exerted by means of an actuator device such that the amplifier body is adjustable by means of the brake support force, wherein the first rod piston component contacts a first contact surface of the amplifier body or a first connecting component contacting the first contact surface of the amplifier body at least temporarily in such a way that the brake support force can be transferred at least partially to the first rod piston component, and the second rod piston component contacts a second contact surface of the amplifier body or a second connecting component contacting the second contact surface of the amplifier body at least temporarily in such a way that the brake support force can be transferred at least partially to the second rod piston component.Thus, by means of an actuator operating the brake booster device, both rod piston components can be adjusted simultaneously or independently of each other.

[0023] Furthermore, the brake booster device can include an input rod component on which a brake actuating element can be arranged in such a way that a driver braking force exerted on the brake actuating element can be transmitted to the input rod component, wherein the input rod component is at least temporarily in direct or indirect contact with the first rod piston component in such a way that the driver braking force can be transmitted at least partially to the first rod piston component, while at least partial transmission of the driver braking force to the second rod piston component is prevented.The brake booster can thus act on both independent rod piston components in such a way that the movement of the first rod piston component is assisted by the driver's braking force, while the second rod piston component is moved solely by the brake booster without any effort from the driver. This is possible because both rod piston components act on the same first pressure chamber of the master cylinder. In the event of a malfunction of the brake booster, such as a failure of the brake booster, the driver can still adjust the first rod piston component to increase the pressure in the first pressure chamber using the driver's braking force. Due to the changed hydraulic ratio, this results in a higher pressure build-up in the first pressure chamber compared to the driver's applied braking force.This can also be described as follows: due to the changed hydraulic transmission, a higher deceleration can be achieved with the same effort.

[0024] The advantages listed above also apply to the corresponding braking system for a vehicle.

[0025] Furthermore, the advantages can also be realized by carrying out the manufacturing process for a master brake cylinder, the manufacturing process for a brake device and the manufacturing process for a brake system. Brief description of the drawings

[0026] Further features and advantages of the present invention are explained below with reference to the figures. They show: Fig. 1 a schematic representation of a first embodiment of the master brake cylinder; Fig. 2a and Fig. 2b a schematic representation and a cross-section of a second embodiment of the master brake cylinder; and Fig. 3a and Fig. 3b a schematic representation and a cross-section of a third embodiment of the master brake cylinder. Embodiments of the invention

[0027] Fig. Figure 1 shows a schematic representation of a first embodiment of the master brake cylinder.

[0028] The in Fig. The master brake cylinder 10, shown schematically, can be used in a vehicle's braking system. For example, the master brake cylinder 10 can be a subunit of a braking device consisting of the master brake cylinder 10 and a brake booster 12. The braking system equipped with the master brake cylinder 10, or the braking system equipped with the braking device, can have any number of brake circuits 14a and 14b, each with at least one wheel brake cylinder 16a and 16b. The design of the in Fig. The schematic representation of the braking system as a dual-circuit braking system is merely an example.

[0029] The master brake cylinder 10 has a first pressure chamber 18. A first rod piston component 20 is adjustable into a first partial pressure chamber 22 of the first pressure chamber 18 such that a first residual volume of the first partial pressure chamber 22, which can be filled with liquid, can be reduced by adjusting the first rod piston component 20. The master brake cylinder 10 also includes a second partial pressure chamber 24 of the first pressure chamber 18, into which a second rod piston component 26 can be adjusted such that a second residual volume of the second partial pressure chamber 24, which can be filled with liquid, can be reduced by adjusting the second rod piston component 26. The first partial pressure chamber 22 and the second partial pressure chamber 24 are separated from each other by at least one partial partition 28.It should be noted that the separation of the two partial pressure chambers 22 and 24 from each other does not necessarily imply sealing. Instead, the separation of the two partial pressure chambers 22 and 24 from each other can also simply be understood as a spatial / abstract separation / delimitation. The at least two partial pressure chambers 22 and 24 can also be configured parallel to each other.

[0030] Preferably, the two partial pressure chambers 22 and 24 are hydraulically connected to each other, despite the partial partition 28 formed at least between them, such that fluid exchange between the partial residual volumes of the two partial pressure chambers 22 and 24 is ensured (at least in a certain operating mode of the first pressure chamber 18). This can also be described as follows: (at least in the respective operating mode of the first pressure chamber 18) due to the hydraulic connection between the two partial pressure chambers 22 and 24, or the fluid exchange caused by it, a common internal pressure exists in both partial pressure chambers 22 and 24. Thus, despite the partial partition 28 projecting into it, the first pressure chamber 18 can still be described as a pressure chamber with a single internal pressure.The partial partition 28 can therefore be understood, for example, as a partition with a flow opening and / or an interrupted partition.

[0031] Likewise, as in Fig. As shown schematically in Figure 1, the second partial pressure chamber 24 is separated from the first partial pressure chamber 22 by a partition wall 28, which is closed off from the first partial pressure chamber 22. To ensure pressure equalization between the two partial pressure chambers 22 and 24, the first partial pressure chamber 22 can be hydraulically connected to the second partial pressure chamber 24 via an externally routed line 30, such that the common internal pressure is present in the first pressure chamber 18, which comprises at least the first partial pressure chamber 22 and the second partial pressure chamber 24. The externally routed line 30 can also be a subunit of the first brake circuit 14a assigned to the first pressure chamber 18. This can be achieved, for example, by hydraulically connecting the first brake circuit 14a to each of the two partial pressure chambers 22 and 24 via a bore 32.

[0032] The first rod piston component 20 and / or the second rod piston component 26 can, for example, be designed as rod pistons. The first rod piston component 20 and / or the second rod piston component 26 can also be described as primary pistons or input pistons. However, it should be noted that the design of the first rod piston component 20 and the second rod piston component 26 is not limited to rod pistons / primary pistons. For example, the first rod piston component 20 and / or the second rod piston component 26 can also be designed as master brake cylinder pistons, each interacting with a piston rod 34 or 36. In the Fig. In the schematically represented embodiment, the first rod-piston component 20 can be adjusted into the first partial pressure chamber 22 by means of a first piston rod 34, whereby it is braked into the first partial pressure chamber 22 at a limiting surface F1 of the first rod-piston component 20. This can also be described as follows: the first limiting surface F1 of the rod-piston component 20 limits the first partial residual volume of the first partial pressure chamber 22. Accordingly, a second limiting surface F2 of the second rod-piston component, which limits the second partial residual volume of the second partial pressure chamber 24, can be displaced by means of a force transmission contact between a second piston rod 36 and the second rod-piston component 26.

[0033] The first rod piston component 20 and / or the second rod piston component 26 can be formed in one piece. Likewise, the first rod piston component 20 and / or the second rod piston component 26 can also be composed of several assembled subunits.

[0034] Preferably, the first rod-piston component 20 is adjustable along a first adjustment direction 35, which is parallel to a second adjustment direction 37 of the second rod-piston component 26. In particular, the first adjustment direction 35 can be aligned with the second adjustment direction 37. The first rod-piston component 20 is preferably adjustable without moving the second rod-piston component 26. The advantageous adjustability of the first rod-piston component 20 can be independent of the position of the second rod-piston component 26. Similarly, the second rod-piston component 26 can also be adjustable without moving the first rod-piston component 20 and / or independently of the position of the first rod-piston component 20.

[0035] The master brake cylinder 10 thus achieves a separation / subdivision of a rod piston component (primary piston) adjustable into the first pressure chamber 18 of the master brake cylinder 10 into two differently and independently adjustable rod piston components 20 and 26, or a separation / subdivision of the associated first pressure chamber 18. By means of this separation, the (actual) contact area in the first pressure chamber 18 of the master brake cylinder 10 can be varied. In particular, this enables staged brake force amplification.

[0036] In a further development, the master brake cylinder 10 can additionally include a second pressure chamber 38 into which a floating piston component 40, such as a floating piston, projects in such a way that the residual volume of the second pressure chamber 38, which can be filled with fluid, can be varied by adjusting the floating piston component 40. (It should be noted that the first rod piston component 20 and the second rod piston component 26 are not to be understood as floating pistons.) Furthermore, a vent bore 42 can be provided on the master brake cylinder 10 for each pressure chamber 18 and 38, through which the respective pressure chamber 18 and 38 are connected to a brake fluid reservoir 44.

[0037] The brake booster device 12, which interacts with the master brake cylinder 10, can comprise a booster body 46 on which a brake assist force can be exerted by means of an actuator (not shown) such that the booster body 46 is adjustable by means of the brake assist force. The first rod-piston component 20 can contact a first contact surface 48 of the booster body 46 or a first connecting component contacting the first contact surface 48 of the booster body 46, such as the first piston rod 34, at least temporarily, such that the brake assist force can be transmitted at least partially to the first rod-piston component 20. Furthermore, the second rod-piston component 26 can contact a second contact surface 50 of the booster body 46 at least temporarily such that the brake assist force can be transmitted at least partially to the second rod-piston component 26.This can be easily ensured by designing the second piston rod 36 as a subunit of the amplifier body 46. Likewise, the second rod-piston component 26, or a second connecting component (not shown) contacting the second contact surface 50 of the amplifier body 46, can at least temporarily make contact such that the brake support force can be at least partially transferred to the second rod-piston component 26.

[0038] The components of the brake booster device 12 described in the paragraph above are in Fig. Figure 1 is shown only schematically. For information regarding the possible design of the brake booster device 12 and the usability of the master brake cylinder 10 described above, particularly for compensating for a functional impairment of the brake booster device 12, please refer to the following figures.

[0039] Fig. 2a and Fig. Figure 2b shows a schematic representation and a cross-section of a second embodiment of the master brake cylinder.

[0040] At the in Fig. In the master brake cylinder shown schematically in Figure 2a, the second pressure chamber 24 is separated from the first partial pressure chamber 22 by a partition 28 with at least one continuous flow opening 60 (as a partial partition). Fluid exchange through the flow opening 60 ensures that a common internal pressure exists in the first pressure chamber 18, which comprises at least the first partial pressure chamber 22 and the second partial pressure chamber 24. Therefore, it is sufficient to hydraulically connect only one of the two partial pressure chambers 22 and 24, such as the second partial pressure chamber 24, to the brake circuit 14a assigned to the first pressure chamber 18 via a bore 32.

[0041] Fig. Figure 2b shows a cross-section through the two rod piston components 20 and 26 along line AA'. As shown by the Fig. As can be seen in Figure 2b, the second rod piston component 26 has a continuous recess into which at least part of the first rod component 20 projects adjustably. The second rod piston component 26 has, in particular, an annular cross-section. Furthermore, the second partial pressure chamber 24 is rotationally symmetrical about a central longitudinal axis of the first partial pressure chamber 22 (running along the first adjustment direction 35). Thus, a rotationally symmetrical counter-pressure distribution is also ensured when braking into the first pressure chamber 18 with both rod piston components 20 and 26. This facilitates uniform braking into the first pressure chamber 18, even at a comparatively high pressure present therein. However, the design possibilities of the two rod piston components 20 and 26 and the master brake cylinder 10 are not limited to this embodiment.

[0042] For example, the first partial pressure chamber 22 can have a first maximum length I1 along the first adjustment direction 35 (with the first rod piston component 20 in its furthest extended position), which is smaller than a second maximum length I2 of the second partial pressure chamber 24 along the second adjustment direction 37 (with the second rod piston component 26 in its furthest extended position). Alternatively or additionally, the first partial pressure chamber 22 can also have a first width b1 perpendicular to the first adjustment direction 35, which is larger than a second width b2 of the second partial pressure chamber 24 perpendicular to the second adjustment direction 37. However, it should be noted that considerable design freedom is available regarding the dimensions of the two partial pressure chambers 22 and 24.

[0043] The in Fig. Figure 2a, schematically depicted, shows a brake booster device 12 comprising a housing 62 with a return spring 64 inserted therein, which presses the booster body 46 into its initial position. The booster body 46 can be adjusted from its initial position onto the master brake cylinder 10 by means of a brake assist force Fu of an actuator (not shown) (opposing the force of the return spring 64). The first rod piston component 20 contacts at least temporarily a first connecting component designed as a reaction disk 66 and reaction disk guide 68, which contacts a first contact surface 48 of the booster body 46 at least temporarily such that the brake assist force Fu can be transmitted at least partially to the first rod piston component 20.Furthermore, the second rod piston component 26 contacts a second contact surface 50 of the amplifier body 46 at least temporarily in such a way that the brake support force can be transferred at least partially to the second rod piston component 26.

[0044] The first contact surface 48 can also be understood to be several separate sub-surfaces. Similarly, the second contact surface 50 can also be subdivided into several separate sub-surfaces. (The use of the singular in the term "contact surface" is solely for clarity.) However, it should be noted that the first contact surface 48 and the second contact surface 50 preferably refer to different (total) areas. This can also be described by stating that the two contact surfaces 48 and 50 preferably do not overlap. Preferably, the contact surfaces 48 and 50 are not congruent.

[0045] Furthermore, the brake booster device 12 can include an input rod component 70 on which a (not shown) brake actuation element can be arranged such that a driver braking force Fb exerted on the brake actuation element can be transmitted to the input rod component 70. The brake actuation element that can be arranged can, for example, be a brake pedal. However, instead of a brake pedal, a differently designed brake actuation element can also be arranged on the input rod component 70.

[0046] The input rod component 70 can be in contact with the first rod piston component 20, at least temporarily (via a contacting element 72), such that the driver's braking force Fb can be transmitted, at least partially, to the first rod component 20. Conversely, even partial transmission of the driver's braking force Fb to the second rod piston component 26 is prevented. Preventing at least partial transmission of the driver's braking force Fb to the second rod piston component 26 preferably does not refer to an active process. Instead, the input rod component 70 can contact the first rod piston component 20, at least temporarily, in such a way that no driver's braking force Fb is transmitted to the second rod piston component 26.

[0047] The brake booster device 12 thus implements a brake booster that acts on the two independently adjustable rod piston components 20 and 26. In the brake booster device 12, the first rod piston component 20 can be moved by the driver's braking force Fb (assisted by the actuator 12). In contrast, the second rod piston component 26 can be moved without any effort from the driver by means of the (hydraulic or electromechanical) actuator.

[0048] In particular, if the actuator is in a deactivated / impaired state, the first rod piston component 20 can still be moved into the master cylinder by means of the driver's braking force Fb. The advantageous split design of the rod piston in this case offers the benefit that, if the actuator / brake booster device 12 malfunctions, only the first rod piston component 20 can be moved by actuating the brake actuating element, while the second rod piston component 26 remains in a specific position despite the driver's actuation of the brake actuating element. The driver therefore does not have to brake with the total contact area equal to the sum of the limiting areas F1 + F2, but only with a reduced contact area equal to the first limiting area F1, into the first pressure chamber 18 of the master cylinder 10.In this way, a higher braking effect is achieved by means of a modified hydraulic ratio, despite a constant driver braking force Fb. This can also be described as follows: due to the reduced contact area equal to the first boundary surface F1, the driver braking force Fb causes a greater pressure build-up in the master brake cylinder 10. Thus, the functional impairment of the actuator / brake booster device 12, due to the advantageous design of the master brake cylinder 10, can be compensated for, at least partially, by means of an increased contact force-brake pressure ratio.

[0049] Furthermore, due to the advantageous division into at least two separate partial pressure chambers 22 and 24, the braking volume of the first pressure chamber 18 can be reduced in the event of a malfunction of the brake booster device 12. This further improves the compensability of a malfunction / failure of the brake booster device 12.

[0050] Fig. 3a and Fig. Figure 3b shows a schematic representation and a cross-section of a third embodiment of the master brake cylinder.

[0051] In addition to the first embodiment described above, the master brake cylinder 10 comprises a third partial pressure chamber 80 of the first pressure chamber 18, which is separated from the first partial pressure chamber 22 by at least one further partition 82. For an explanation of how the third partial pressure chamber 80 is separated from the first partial pressure chamber 22, please refer to the descriptions above. As an alternative to separating the third partial pressure chamber 80 from the first partial pressure chamber 22, the third partial pressure chamber 80 can also be separated from the second partial pressure chamber 24 by at least one further partition 82.

[0052] The third partial pressure chamber 80 is designed such that a third rod piston component 84 can be adjusted into it in such a way that a third residual volume of the third partial pressure chamber 80, which can be filled with liquid, can be reduced by adjusting the third rod piston component 84. Furthermore, at least one hydraulic connection 86 between the first partial pressure chamber 22 and the third partial pressure chamber 80 and / or between the second partial pressure chamber 24 and the third partial pressure chamber 80 can be designed such that a common internal pressure in the at least three partial pressure chambers 22, 24, and 80 of the first pressure chamber 18 can be set. The at least one hydraulic connection 86 can, for example, comprise a flow opening in the further partition wall 82 and / or an externally routed line.

[0053] Thus, by adjusting the third rod piston component 84 in the third partial pressure chamber 80, the pressure present in the at least three partial pressure chambers 22, 24, 80 of the first pressure chamber 18 can also be varied / adjusted. The in Fig. The master brake cylinder 10 shown schematically in 3a can therefore be used for two- or three-stage brake force amplification.

[0054] In a preferred training program, which is based on the Fig.As shown in Figure 3b as a cross-section along line BB', the third rod piston component 84 is mirror-symmetrical to the second rod piston component 26 with respect to a plane of symmetry 88 that intersects the first rod piston component 20 at its center. Likewise, the third partial pressure chamber 80 can be mirror-symmetrical to the second partial pressure chamber 24 with respect to a plane of symmetry (not shown) that intersects the first partial pressure chamber 22 at its center. This ensures an advantageous spatial pressure / force distribution when the three rod piston components 20, 26, and 84 are simultaneously inserted into their respective partial pressure chambers 22, 24, and 80. Additionally, the outer contours of the three rod piston components 20, 26, and 84, or the three partial pressure chambers 22, 24, and 80, can be cylindrical.In particular, the diameter d1 of the first partial pressure chamber 22, perpendicular to the first adjustment direction 35 of the first rod piston component 20, can be twice the diameter d2 of the second partial pressure chamber 24, perpendicular to the second adjustment direction 37 of the second piston component 26, and / or twice the diameter d3 of the third partial pressure chamber 80, perpendicular to a third adjustment direction 90 of the third rod piston component 84. However, considerable design freedom is ensured with regard to the dimensions of the three partial pressure chambers 22, 24, and 80.

[0055] Furthermore, the third rod piston component 84 can at least temporarily contact a third contact surface 92 of the amplifier body 46 or a third connecting component (not shown) that contacts the third contact surface 92 of the amplifier body 46, such that the brake assist force Fu can be at least partially transmitted to the third rod piston component 84. Conversely, the transmission of the driver braking force Fb (passed on via the brake actuation element 94) to the third rod piston component 84 can be prevented. Thus, the third rod piston component 84 can be used to support the brake force amplification achieved by means of the second rod piston component 26.

[0056] By separating the first pressure chamber 18 into the three partial pressure chambers 22, 24, and 80, a staged brake force amplification is also possible in this embodiment of the master brake cylinder. Part of the brake force amplification is introduced directly into the hydraulic system, while another part can be used to assist the driver in actuating the brake actuating element 94 or to counteract recoil (e.g., from the spring 96). In the event of a failure of the brake force booster device, a hydraulic transmission is activated in the master brake cylinder 10 described here, which allows for higher deceleration with identical actuation forces. Thus, the master brake cylinder 10 can also be used as a volume booster.

[0057] The master brake cylinders 10 described above can be easily integrated as an additional component in a hydraulic brake system. It should be noted that the use of the master brake cylinders 10 is not limited to a specific vehicle type, such as a hybrid or electric vehicle.

[0058] Each of the master brake cylinders 10 can be designed by appropriately defining its functions so that, in the event of a failure of the brake booster device, a deceleration of 2.44 m / s can still be achieved even with a driver braking force of only 500 N. 2 is reachable. Furthermore, the master brake cylinder 10 can be designed without regard to the deceleration still achievable in the event of a malfunction of the brake booster device 12. Nevertheless, even higher decelerations can be achieved by means of each of the master brake cylinders 10 in the event of a failure of the brake booster device 12.

[0059] A further advantage of the embodiments of the master brake cylinder 10 described above is that, at least in some braking systems, a vehicle deceleration of up to 6.44 m / s² is possible. 2 With a driver braking force Fb of 500 N, rapid deceleration can be achieved even with the ignition key removed. This deceleration can also be achieved with a "dormant" brake system.

[0060] The advantageous manufacturing processes are schematically illustrated using the embodiments of the master brake cylinders described above. Therefore, a further description of the manufacturing processes is omitted here.

Claims

[1] Master brake cylinder (10) for a braking system of a vehicle with: a first pressure chamber (18), wherein a first rod piston component (20) is adjustable into at least a first partial pressure chamber (22) of the first pressure chamber (18) such that a first partial residual volume of the first partial pressure chamber (22) that can be filled with liquid can be reduced by adjusting the first rod piston component (20); characterized by a second partial pressure chamber (24) of the first pressure chamber (18), which is separated from the first partial pressure chamber (22) by at least a partial partition (28), and into which a second rod piston component (26) can be adjusted such that a second residual volume of the second partial pressure chamber (24) which can be filled with liquid can be reduced by adjusting the second rod piston component (26), wherein the master brake cylinder (10) comprises the first rod piston component (20) and the second rod piston component (26), and wherein the second rod piston component (26) has a continuous recess into which at least a part of the first rod piston component (20) projects adjustably. [2] Master brake cylinder (10) according to claim 1, wherein the second partial pressure chamber (24) is separated from the first partial pressure chamber (22) by a partition wall with at least one continuous flow opening (60) as a partial partition wall (28) such that a common internal pressure of the first partial pressure chamber (22) and the second partial pressure chamber (24) is present in the first pressure chamber (18) comprising at least the first partial pressure chamber (22) and the second partial pressure chamber (24). [3] Master brake cylinder (10) according to claim 1, wherein the second partial pressure chamber (24) is separated from the first partial pressure chamber (22) by a partition wall without openings as a partial partition wall (28), and the first partial pressure chamber (22) is hydraulically connected to the second partial pressure chamber (24) via an externally routed line (30) such that the common internal pressure of the first partial pressure chamber (22) and the second partial pressure chamber (24) is present in the first pressure chamber (18) comprising at least the first partial pressure chamber (22) and the second partial pressure chamber (24). [4] Master brake cylinder (10) according to one of the preceding claims, wherein the master brake cylinder (10) comprises a second pressure chamber (38) into which a floating piston component (40) projects such that a residual volume of the second pressure chamber (38) that can be filled with liquid can be varied by adjusting the floating piston component (40). [5] Master brake cylinder (10) according to one of the preceding claims, wherein the second partial pressure chamber (24) is rotationally symmetric to a central longitudinal axis of the first partial pressure chamber (22). [6] Master brake cylinder (10) according to one of the preceding claims, wherein the master brake cylinder (10) comprises a third partial pressure chamber (80) of the first pressure chamber (18), which is separated from the first partial pressure chamber (22) and / or the second partial pressure chamber (24) by at least one further partial partition (82), and into which a third rod piston component (84) can be adjusted such that a third residual volume of the third partial pressure chamber (80) that can be filled with liquid can be reduced by adjusting the third rod piston component (84). [7] Master brake cylinder (10) according to claim 6, wherein the third partial pressure chamber (80) is designed in a mirror-symmetrical manner to the second partial pressure chamber (24) with respect to a plane of symmetry (88) which intersects the first partial pressure chamber (22) in the middle. [8] Brake device for a vehicle braking system with a master brake cylinder (10) according to one of the preceding claims; and a brake booster device (12). [9] Brake device according to claim 8 comprising: an amplifier body (46) of the brake booster device (12), on which a brake support force (Fu) can be exerted by means of an actuator device such that the amplifier body (46) is adjustable by means of the brake support force (Fu); wherein the first rod piston component (20) contacts a first contact surface (48) of the amplifier body (46) or a first connecting component (66, 68) contacting the first contact surface (48) of the amplifier body (46) at least temporarily in such a way that the brake support force (Fu) is at least partially transferable to the first rod piston component (20); and the second rod piston component (26) contacts a second contact surface (50) of the amplifier body (46) or a second connecting component contacting the second contact surface (50) of the amplifier body (46) at least temporarily in such a way that the brake support force (Fu) can be transferred at least partially to the second rod piston component (26). [10] Brake device according to claim 9, wherein the brake booster device (12) comprises an input rod component (70) on which a brake actuating element (94) can be arranged such that a driver braking force (Fb) exerted on the brake actuating element (94) can be transmitted to the input rod component (70), and wherein the input rod component (70) is at least temporarily in direct or indirect contact with the first rod piston component (20) such that the driver braking force (Fb) can be transmitted at least partially to the first rod piston component (20), while at least partial transmission of the driver braking force (Fb) to the second rod piston component (26) is prevented. [11] Braking system for a vehicle with at least one brake circuit (14a, 14b); and a master brake cylinder (10) according to one of claims 1 to 7 and a brake booster device (12); or a braking device according to one of claims 8 to 10. [12] Manufacturing process for a master brake cylinder (10) comprising the step: Forming at least one first partial pressure chamber (22) of a first pressure chamber (18) such that, when the master brake cylinder (10) is operated, a first residual volume of the first partial pressure chamber (22) that can be filled with liquid is reduced by moving a first rod piston component (20) into the first partial pressure chamber (22); characterized by the step: Additional formation of a second partial pressure chamber (24) of the first pressure chamber (18), which is separated from the first partial pressure chamber (22) by at least a partial partition (28), such that during operation of the master brake cylinder (10) by moving a second rod piston component (26) into the second partial pressure chamber (24) a second residual volume of the second partial pressure chamber (24) that can be filled with liquid is reduced. wherein the master brake cylinder (10) comprises the first rod piston assembly (20) and the second rod piston assembly (26), and wherein the second rod piston assembly (26) has a continuous recess into which at least a part of the first rod piston assembly (20) adjustably projects. [13] Manufacturing process for a brake device comprising the steps: Manufacturing a master brake cylinder (10) according to the method of claim 12; and Arranging the master brake cylinder (10) on a brake booster device (12). [14] Manufacturing process for a brake system comprising the steps: Manufacturing a master brake cylinder (10) according to the method of claim 12 and arranging the master brake cylinder (10) on a brake booster device (12); or Manufacturing a braking device according to the method of claim 13; and Forming at least one brake circuit (14a, 14b) on the master brake cylinder (10).

Images