Axial force transmitter for an operating device of a brake system and method for manufacturing the same - Patents.com

Abstract

One aspect of the present invention relates to an axial force transmitter (17) for an operating device (1) of a brake device, the axial force transmitter (17) comprising an elongated first component (19) and an elongated second component (21), the first component (19) having a sleeve section (27), a first end section (29) of the second component (21) axially extending into the sleeve section (27), the sleeve section (27) and the first end section (29) of the second component (21) being axially fixedly connected to each other, and the sleeve section (27) and the first end section (29) of the second component (21) being axially fixedly connected to each other by pressure deformation of the sleeve section (27). Another aspect of the present invention relates to a method for manufacturing an axial force transmitter.

Description

[Technical Field]

[0001] The present invention relates to an axial force transmitter for an operating device of a brake device, comprising an elongated first component and an elongated second component, the first component having a sleeve section, a first end section of the second component axially extending into the sleeve section, and the sleeve section and the first end section of the second component being axially fixedly connected to each other.

[0002] Furthermore, the invention relates to an actuating device for a braking system, which comprises an axial force transmitter of this kind.

[0003] The present invention further relates to a method for manufacturing an axial force transmitter. [Background technology]

[0004] Brake systems of motor vehicles typically have an actuating device that is configured to actuate the main brake cylinder of the brake system, i.e., to move a hydraulic piston supported in the main brake cylinder. This type of actuating device generally includes a movable axial force transmitter that is connected to the brake pedal of the brake system. The actuating device is configured to actuate the main brake cylinder in response to the movement of the axial force transmitter. The prior art discloses two-part axial force transmitters that include an elongated first component and an elongated second component, the first and second components being axially fixedly connected to one another. The axially fixed connection is often achieved by the first component having a sleeve section into which a first end section of a second component axially projects, and then the sleeve section and the first end section of the second component being axially fixedly connected to one another.

[0005] In previously known axial force transmitters, the axially fixed connection is typically provided by a threaded connection, in that the sleeve section has an internal thread and the first end section of the second component has an external thread that is screwed into the internal thread. Summary of the Invention [Effects of the Invention]

[0006] The axial force transmitter according to the present invention, having the features of claim 1, has the advantage that the structural design of the first and second components can be simplified compared to previously known solutions. This provides advantages with regard to the manufacture of the first and second components. According to the present invention, the sleeve section and the first end section of the second component are axially and securely connected to one another by pressure-forming the sleeve section. Pressure-forming, in this case, should be understood as a method of applying a press force to the components, thereby deforming the components. The components are thus deformed by pressure. In this respect, the sleeve section has at least one deformed region, which is responsible for at least part of the axially fixed connection. Because the components are connected to one another by pressure-forming, the previously mentioned threads and wrench faces for transmitting torque during screw tightening are not required. Preferably, the threads and wrench faces are omitted. This, in particular, results in the simplification of the structural design of the components according to the present invention. The first component is an elongated component. In this respect, the first component has a central longitudinal axis. When the terms "axial" and "radial" are used within the scope of this disclosure, these terms typically relate to the central longitudinal axis of the first component, unless expressly stated otherwise. The second component is also an elongated component. In this respect, the second component also has a central longitudinal axis. Preferably, the components are connected to each other such that their central longitudinal axes are aligned with each other. The first and second components are coaxial in this case. Particularly preferably, the first and / or second components are rotationally symmetrical about their respective central longitudinal axes, at least prior to forming the axially fixed connection. The first and second components are connected to each other in an axially fixed manner. In this respect, the components are connected to each other by a connection that is configured to transmit axial forces, i.e., to transmit both pushing and pulling forces in the axial direction.

[0007] Preferably, the sleeve section has at least one bulge that projects radially inward to form the axially secure connection. The bulge is a deformed region of the sleeve section or a deformed region of the sleeve wall or surrounding wall of the sleeve section. In this regard, the bulge is produced by pressure deformation of the sleeve section with a pressing force acting radially inward. Preferably, at least part of the axially secure connection is produced by form-fitting. In this regard, the radially inward bulge radially engages in a radial cavity of the first end section of the second component. In this type of configuration, the axially secure connection allows for the transmission of particularly high axial forces. Preferably, at least part of the axially secure connection is produced by force-fitting.

[0008] Preferably, the sleeve section has a plurality of radially inwardly projecting bulges, which are evenly distributed around the circumference of the sleeve section. This provides a particularly stable, axially fixed connection. Particularly preferably, the sleeve section has exactly three radially inwardly projecting bulges. Preferably, the bulges have an at least approximately circular cross section. In this respect, the bulges are produced by pressure deformation using a press punch with a circular punch face. Preferably, the deformed sleeve section has n-fold rotational symmetry about the axis of rotation, where n corresponds to the number of bulges. Such a rotationally symmetric sleeve section can be obtained when multiple bulges are formed simultaneously, i.e., when a press force is simultaneously applied to the sleeve section at multiple locations that are evenly distributed around the circumference of the sleeve section.

[0009] According to a preferred embodiment, the first end section of the second component and the sleeve section are axially fixedly connected to one another by pressure deformation of the first end section. In this respect, at least a partial region of the first end section is also deformed, and the axially fixed connection is provided by deformation of the first end section of the second component. Preferably, the first end section of the second component has a number of recesses corresponding to the number of bulges, each of which radially engages in a respective recess. The previously mentioned radial gaps are formed in this case by the recesses. If the sleeve section has, for example, exactly three bulges, the first end section of the second component has a triangular cross section due to deformation of the first end section.

[0010] According to a preferred embodiment, the second component has an axial bore, which simplifies deformation of the second component, in that lower press forces are required during the press-forming process to provide an axially fixed connection.

[0011] Preferably, the second component has a groove that extends circumferentially through the second component and the bulge engages radially within the groove to form an axially fixed connection. This embodiment is particularly advantageous when the second component is made of a harder material than the first component, such that deformation of the second component is difficult. The previously mentioned radial gap is in this case formed by the groove.

[0012] According to a preferred embodiment, the end face of the second component rests axially against the bottom portion that axially defines the sleeve section. The axial resting of the end face against the bottom portion allows the axial force transmitter to transmit particularly high pushing forces. The end face of the sleeve section is preferably free in this embodiment, so that the second component does not rest axially against the end face of the sleeve section.

[0013] According to an alternative embodiment, the second component preferably has an axial stop that abuts against the end face of the sleeve section in the axial direction. The first end section of the second component has a smaller radial extension than the base body of the second component that includes the axial stop. The second component is stepped in this respect. The axial stop abutting against the end face of the sleeve section also allows the axial force transmitter to transmit particularly high pushing forces. Additionally, by forming the second component in a stepped form, the radial extension of the sleeve section of the first component can be reduced, since the sleeve section only needs to accommodate the first end section, which has a smaller radial extension, in the axial direction.

[0014] The actuating device according to the invention for a braking system comprises a movable axial force transmitter, which can be / is connectable to the brake pedal. The actuating device is characterized in that the axial force transmitter is formed according to the invention, which also results in the advantages already mentioned. Further preferred features and feature combinations are evident from the description and the claims.

[0015] According to a preferred embodiment, the second component is arranged at least partially within a sleeve-shaped housing section of the actuating device, the sleeve section being dimensioned so that it can be pressed into the housing section. The radial extension of the sleeve section is therefore smaller than the radial extension of the axial receiving portion of the sleeve-shaped housing section, in which the second component is arranged. Since the sleeve section can also be pressed into the sleeve-shaped housing section, the axial extension of the second component can be reduced. This allows the overall installation space required for the actuating device to be reduced.

[0016] Preferably, the operating device comprises a bellows radially surrounding the second component, a first end of the bellows attached to the sleeve-shaped housing section, and a second end of the bellows radially surrounding the sleeve section of the first component and attached to the first component. Essentially, the bellows prevents foreign matter from reaching the interior of the sleeve-shaped housing section. Since the bellows also radially surrounds the sleeve section of the first component, the bellows additionally prevents foreign matter from reaching the area of ​​the axially fixed connection. Preferably, the first end of the bellows is attached to the sleeve-shaped housing section by a locking connection. Preferably, the second end of the bellows is attached to the first component by a locking connection, for example, by locking the second end into a groove in the first component.

[0017] Preferably, the sleeve section has a chamfer for fitting the bellows thereon, which simplifies the installation of the bellows.

[0018] According to a preferred embodiment, the first component has an axial stop for the second end of the bellows, which ensures a secure axial fixing of the bellows to the first component, in particular preventing the second end of the bellows from slipping over the axial stop.

[0019] A method for producing an axial force transmitter according to the invention, as defined in claim 14, comprises providing an elongated first component having a sleeve section, providing an elongated second component, arranging the first and second components so that the first end section of the second component axially extends into the sleeve section, and deforming the sleeve section by pressure deformation so that the sleeve section and the first end section of the second component are axially fixedly connected to each other. This also results in the advantages already mentioned. Further preferred features and combinations of features are apparent from the description and claims. Preferably, the first end section of the second component is also deformed during pressure deformation of the sleeve section. Preferably, a clinching method is performed for pressure deformation.

[0020] According to a preferred embodiment of the method, the pressing force is applied to the sleeve section simultaneously at multiple locations that are evenly distributed around the circumference of the sleeve section. This prevents uneven deformation of the component. Instead, this deformation results in a sleeve section that is rotationally symmetrical about the n-fold axis of rotation, where n corresponds to the number of locations to which the pressing force is applied. According to an alternative embodiment, the pressing force is applied at multiple locations with time intervals.

[0021] The present invention will be described in detail below with reference to the drawings. [Brief explanation of the drawings]

[0022] [Figure 1] FIG. [Figure 2] 1A-1C show several embodiments of an axial force transmitter of an operating device, comprising a first and a second component; [Figure 3] 10A-10C show several examples of the second component. [Figure 4] 1A-1C illustrate a method for manufacturing an axial force transmitter. [Figure 5] FIG. 10 shows the first and second components after the axial fixing connection between the components has been released. DETAILED DESCRIPTION OF THE INVENTION

[0023] FIG. 1 shows, in a cross-section, an actuating device 1 for a braking system (not shown in detail) of a motor vehicle. The actuating device 1 has a housing 3. The housing 3 has a housing plate 5 and a sleeve-shaped housing section 7. The housing section 7 has a front plate 9, in which an axial through-hole 11 is formed. An actuating element 13 is supported axially movably inside the housing section 7. When the actuating element 13 is moved in an actuating direction 15, the actuating element 13 actuates a main brake cylinder (not shown) of the braking system.

[0024] The operating device 1 further comprises an axially movable axial force transmitter 17. The axial force transmitter 17 comprises an elongated or rod-shaped first component 19 and an elongated or rod-shaped second component 21. Components 19 and 21 are arranged coaxially with one another. A central longitudinal axis 23 of the first component 19 is therefore aligned with a central longitudinal axis 25 of the second component 21.

[0025] The components 19 and 21 are axially fixedly connected to one another. This connection between the components 19 and 21 allows for the transmission of axial forces acting in both the operating direction 15 and the opposite direction. For example, when an axial force acting in the operating direction 15 is applied to the first component 19, the second component 21 moves together with the first component 19 in the operating direction 15. When an axial force acting in the opposite direction to the operating direction 15 is applied to the first component 19, the second component 21 moves together with the first component 19 in this direction. The components 19 and 21 are rigid. This makes the entire axial force transmitter 17 rigid. The components 19 and 21 are made of a steel material, such as stainless steel or coated steel, and are coated with, for example, Zn or ZnNi.

[0026] The first component 19 has a sleeve section 27. A first end section 29 of the second component 21, not visible in FIG. 1 , engages axially within the sleeve section 27. The sleeve section 27 and the first end section 29 of the second component 21 are axially fixedly connected to one another by press-forming the sleeve section 27. A pressing force is applied to the sleeve section 27 at at least one location, which deforms the sleeve section 27 so that the first component 19 and the second component 21 are axially fixedly connected to one another. Due to the application of the pressing force, the sleeve section 27 has at least one bulge that extends radially toward the first end section 29 of the second component 21. This bulge engages in a radial cavity in the first end section 29 of the second component 21. Various embodiments of this will be described in more detail below with reference to FIG. 3. Preferably, the sleeve section 27 has a plurality of bulges, which are evenly distributed around the circumference of the sleeve section 27. Preferably, the bulges each have a circular cross section. Bulges of this type are obtained when the pressing force is provided by a pressing punch with a circular punch surface.

[0027] The sleeve section 27 is dimensioned so that it can be pressed into the housing section 7. The radial extension of the sleeve section 27 is therefore smaller than the radial extension of the axial through-hole 11.

[0028] The second end section 31 of the first component 19 has an enlarged diameter portion 33, by means of which the first component 19 can be connected to a brake pedal of a brake system. The second end section 31 of the first component 19 corresponds to a rear end 35 of the axial force transmitter 17 in the actuation direction 15. The second end section 37 of the second component 21 has a spherical joint head 39, which is received in a ball seat 41 of the actuation element 13. The axial force transmitter 17 is connected to the actuation element 13 by a ball joint 43. This means that when the axial force transmitter 17 is moved axially in the actuation direction 15, the actuation element 13 is moved together with the axial force transmitter 17. The second end section 37 of the second component 21 corresponds to a front end 45 of the axial force transmitter 17 in the actuation direction 15.

[0029] The operating device 1 further comprises a bellows 47 which radially surrounds a section of the second component 21 that is arranged outside the housing section 7. A first end 49 of the bellows 47 is attached to the housing section 7. A second end 51 of the bellows 47 radially surrounds the sleeve section 27 and is attached to the first component 19. For this purpose, the first component 19 has a groove 53 which extends circumferentially through the first component 19, and the second end 51 of the bellows 47 is radially engaged in the groove 53.

[0030] To facilitate fitting of the bellows 47 onto the sleeve section 27, the sleeve section 27 has a fitting chamfer 55. To prevent the bellows 47 from being fitted over the groove 53, the first component 19 has an axial stop 57. The axial stop 57 is arranged axially between the groove 53 on the one hand and the second end section 31 of the first component 19 on the other hand, and here continues directly into the groove 53.

[0031] 2 shows two embodiments of the axial force transmitter 17 in cross section, which is shown only diagrammatically in this case, e.g., the groove 53, the mating chamfer 55 and the axial stop 57 are not shown.

[0032] According to the upper embodiment, the radial extension 59 of the base 61 of the second component 21 is equal to the radial extension 63 of the first end section 29. The radial extensions 59 and 63 are preferably between 6 and 10 mm, here exactly 8 mm. An end face 65 of the first end section 29 abuts in the axial direction against a bottom 67 of the first component 19, which axially defines the sleeve section 27. The end face 69 of the sleeve section 27 is free in this upper embodiment.

[0033] According to the lower embodiment, the second component 21 is stepped. The radial extension 63 of the end section 29 is therefore smaller than the radial extension 59 of the base body 61. Here, the radial extension 59 is 8 mm, while the radial extension 63 is 6 mm. Due to the stepped design, the base body 61 has an axial stop 71, which axially abuts against the end face 69 of the sleeve section 27. The end face 65 of the first end section 19 is axially spaced from the bottom 67.

[0034] Due to the stepped design of the second component 21, the radial extension 73 of the sleeve section 27 can be reduced in the case of the lower embodiment. For example, the radial extension 73 is 8.5 mm in the lower embodiment and 10.5 mm in the upper embodiment. Correspondingly, the sleeve wall thickness of the sleeve section 27 is 1.25 mm in both embodiments.

[0035] FIG. 3 shows three embodiments of the second component 21, which differ from one another in terms of the configuration of the first end section 29. In this case, the second component 21 is shown in a state before it is axially fixedly connected to the first component 19. In addition, each of the three illustrated embodiments is a stepped second component 21. As an alternative to these three embodiments, the first end section 29 of the second component 21 has the same radial extension as the base body 61, as described above with reference to FIG. 2. The second components 21 shown in FIG. 3 each have an insertion chamfer 75, which facilitates insertion of the second component 21 into the sleeve section 27.

[0036] In the left-hand embodiment, the first end section 29 is cylindrical. Therefore, the first end section 29 has the same radial extent everywhere, except in the region where the insertion chamfer 75 is formed. When the first end section 29 of this left-hand embodiment is inserted axially into the sleeve section 27, which is subsequently deformed by applying a pressing force to the sleeve section 27, a radially inward bulge is formed in the sleeve section. The pressing force is transmitted through the bulge to the first end section 29 of the second component 21, resulting in a complementary recess in the first end section 29, into which the bulge thus radially engages.

[0037] In the middle embodiment, the first end section 29 is also cylindrically shaped. This middle embodiment differs from the left-hand embodiment in that the first end section 29 has an axial bore 77. The provision of the axial bore 77 reduces the pressing force required for the deformation process.

[0038] According to the embodiment on the right, the first end section 29 has a groove 79 that extends circumferentially through the first end section 29. In this embodiment, when a pressing force is applied to the sleeve section 27, the resulting bulge of the sleeve section 27 can radially engage into the groove 79. It is therefore not necessary to deform the first end section 29 in order to create a form-locking, axially fixed connection between the first end section 29 and the sleeve section 27. This embodiment on the right is particularly advantageous when the first component 21 is made of a particularly hard material, so that deformation of the first component 21 is difficult.

[0039] 4 shows a method for manufacturing the axial force transmitter 17. In a first step S1, a first component 19 is provided. In a second step S2, a second component 21 is provided. In a third step S3, the components 19 and 21 are arranged so that a first end section 29 of the second component 21 projects axially into the sleeve section 27.

[0040] In a fourth step S4, the sleeve section 27 is deformed by pressure deformation so that the sleeve section 27 and the first end section 29 of the second component 21 are axially fixedly connected to one another. For this purpose, a pressing force acting radially inward, i.e., toward the second component 21, is applied to the sleeve section 27 at least in one location. As a result, a radially inward bulge is formed in the sleeve section 27. Preferably, a pressing force acting radially inward is applied to the sleeve section 27 simultaneously in multiple locations to form multiple bulges. In particular, the second component 21 is deformed together in step S4. This is the case, for example, when the second component 21 according to the left or center embodiment of FIG. 3 is used. In particular, the second component 21 remains at least substantially shape-stable in step S4. This is the case, for example, when the second component according to the right embodiment of FIG. 3 is used.

[0041] Preferably, step S4 is performed by an apparatus having a stationary anvil and a press punch displaceable toward the anvil, in which case components 19 and 21 are placed in step S3 between the anvil on the one hand and the press punch on the other hand, and a pressing force is applied to sleeve section 27 in step S4 by displacing the press punch toward the anvil.

[0042] Figure 5 shows the first component 19 and the second component 21 after the axially fixed connection between the two components 19 and 21 has been released, for which a tensile force has been applied to the connection that exceeds the limit load of the connection.

[0043] 5, the radially inwardly projecting bulges 81 of the sleeve section 27 are apparent as recesses 81. Upon release of the axially fixed connection, the bulges 81 are at least partially restored to their radially outward position. Additionally, one of the previously mentioned recesses 83 of the first end section 29 is apparent. When the components 19 and 21 are axially fixedly connected to one another, one of the radially inwardly projecting bulges 81 of the sleeve section 27 is radially engaged within the recess 83. [Explanation of symbols]

[0044] 1 Operating device 3. Housing 5 Housing Plate 7 Housing Section 9 Front Plate 11 Axial penetration 13 Operating Elements 15 Operation direction 17 Axial force transmitter 19 First component 21 Second component 23 (of first component 19) longitudinal center axis 25 (of second component 21) longitudinal center axis 27 sleeve section (of first component 19) 29 first end section (of second component 21) 31 second end section (of first component 19) 33 Expanded diameter part 35 (of the axial force transmitter 17) rear end 37 second end section (of second component 21) 39 Joint Head 41 Ball receiving part 43 Ball Joint 45 (of the axial force transmitter 17) front end 47 Bellows 49 (of bellows 47) first end 51 (of bellows 47) second end 53 Groove 55 Chamfered part for fitting 57 Axial stopper 59 Radial extension dimension (of base 61) 61 (of the second component 21) base 63 Radial extension dimension (of first end section 29) 65 (of first end section 29) end face 67 (of the first component 19) bottom 69 (of sleeve section 27) end face 71 Axial stopper 73 Radial extension dimension (of sleeve section 27) 75 Insertion chamfer 77 Axial hole 79 Groove 81 Bulge 83 hollow S1 First Step S2 Second step S3 Third step S4 The fourth step

Claims

1. An operating device for a brake system, comprising a movable axial force transmitter (17), said axial force transmitter (17) being connectable / connected to a brake pedal; In the operating device, The axial force transmitter comprises an elongated first component (19) and an elongated second component (21), the first component (19) having a sleeve section (27), a first end section (29) of the second component (21) axially extending into the sleeve section (27), the sleeve section (27) and the first end section (29) of the second component (21) being axially fixedly connected to one another, the sleeve section (27) and the first end section (29) of the second component (21) are axially fixedly connected to each other by pressure deformation of the sleeve section (27); the second component (21) is arranged at least in a partial section within a sleeve-shaped housing section (7) of the operating device (1), and the sleeve section (27) of the first component (19) is dimensioned such that the sleeve section (27) can be pushed into the housing section (7); a bellows (47) radially surrounding the second component (21), a first end (49) of the bellows (47) being attached to the sleeve-like housing section (7), and a second end (51) of the bellows (47) radially surrounding the sleeve section (27) of the first component (19) and attached to the first component (19); An operating device for a brake device, characterized in that:

2. 2. The operating device according to claim 1, wherein the sleeve section (27) has at least one bulge (81) extending radially inwards to form the axially fixed connection.

3. 3. The operating device according to claim 2, wherein the sleeve section (27) has a plurality of bulges (81) extending radially inward, the bulges (81) being evenly distributed around the circumference of the sleeve section (27).

4. An operating device as described in any one of claims 1 to 3, characterized in that the first end section (29) of the second component (21) and the sleeve section (27) are axially fixedly connected to each other by pressurized deformation processing of the first end section (29) of the second component (21).

5. An operating device as described in any one of claims 1 to 4, characterized in that the second component (21) has an axial hole (77).

6. An operating device as described in claim 2 or 3, characterized in that the second component (21) has a groove (79) that extends circumferentially through the second component (21), and the bulge (81) engages radially within the groove (79) to form the axially fixed connection.

7. An operating device described in any one of claims 1 to 6, characterized in that the end face (65) of the second component (21) abuts axially against a bottom (67) that axially defines the sleeve section (27).

8. An operating device described in any one of claims 1 to 6, characterized in that the second component (21) has an axial stopper (71), and the axial stopper (71) abuts axially against the end face (69) of the sleeve section (27).

9. An operating device as described in claim 1, characterized in that the sleeve section (27) has a chamfered portion (55) for fitting over the bellows (47).

10. An operating device as described in any one of claims 1 to 9, characterized in that the first component (19) has an axial stopper (57) for the second end (51) of the bellows (47).

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