Hydraulic assembly, housing assembly for a hydraulic assembly, and method for manufacturing a housing assembly

Description

Technical field

[0001] The present invention relates to a hydraulic assembly, in particular for a hydraulic brake system, a housing assembly for a hydraulic assembly, and a method for manufacturing a housing assembly. State of the art

[0002] Hydraulic braking systems in vehicles typically employ brake boosters, such as electric motor-driven brake boosters. The operating principle of such brake boosters is based on amplifying the force applied to an actuating device, such as a pedal, by means of an electric motor via a gearbox, which actuates a hydraulic pressure generating device, such as a master brake cylinder. This usually involves the linear adjustment of an actuating assembly coupled to the pressure generating device by the gearbox. The actuating assembly is housed in a casing and mounted to at least one tie rod provided in the casing, allowing for linear displacement.

[0003] German patent application DE 10 2020 206 337 A1 describes a hydraulic assembly comprising a housing assembly and a master brake cylinder as a hydraulic device. The housing assembly includes a housing part and a tie rod extending through an opening in the housing part. The hydraulic device is mounted on an outer surface of the housing part, with the tie rod protruding through a bore in a flange of the hydraulic device. A sealing element for sealing the housing is provided between the flange and an outer surface of the housing to create a fluid-tight seal around the opening of the housing part. A flat tie rod nut is screwed to the tie rod on an inner surface of the housing to secure it. The tie rod nut thus has a short overall length, providing a long guide surface on the tie rod to achieve a sufficient stroke length for an actuating assembly guided by the tie rod, despite the limited overall length.If the hydraulic device is removed from the housing assembly, e.g. for maintenance or replacement, the sealing element must be replaced.

[0004] The KR 2005 0068152 A shows a brake booster for a wagon equipped with a drawbar.

[0005] DE 102010 034827 A1 discloses a vacuum brake booster with an easy-to-install chamber arrangement and a method for installing a vacuum brake booster.

[0006] The GB 2 147 380 A shows a force multiplier for braking systems in vehicles.

[0007] The GB 2 031 086 A reveals a brake booster. Disclosure of the invention

[0008] According to the invention, a housing assembly with the features of claim 1, a hydraulic assembly with the features of claim 9 and a method with the features of claim 10 are provided.

[0009] According to a first aspect of the invention, a housing assembly for a hydraulic assembly comprises a housing part that at least partially encloses an inner volume and has a through-opening which extends between an inner surface facing the inner volume and an outer surface of the housing part oriented opposite to this, wherein a region of the inner surface surrounding the through-opening forms a recess.Furthermore, the housing assembly comprises a tie rod which extends with an inner section into the inner volume of the housing part and which projects through the through-hole, so that an outer section of the tie rod protrudes beyond the outer surface of the housing part, a tie rod nut which is screwed to the inner section of the tie rod and has a sealing surface, and a sealing element which is arranged in the recess and rests against the inner section of the tie rod, against the area of ​​the inner surface surrounding the through-hole and against the sealing surface of the tie rod nut.

[0010] According to a second aspect of the invention, a hydraulic assembly, particularly for a hydraulic braking system, is provided. The hydraulic assembly comprises a housing assembly according to the first aspect of the invention and a hydraulic device with a flange in which a bore is formed. The outer section of the tie rod projects through the bore of the flange, and the hydraulic device is attached to the housing assembly via the tie rod.

[0011] According to a third aspect of the invention, a method for manufacturing a housing assembly is provided, in addition to the first aspect of the invention. The method comprises arranging the sealing element in the recess of the housing part, passing the tie rod through the through-hole of the housing part, screwing the tie rod nut to the tie rod, and contacting the sealing element with the sealing surface of the tie rod nut, the area of ​​the inner surface surrounding the through-hole, and the inner section of the tie rod.

[0012] One of the underlying ideas of the invention is to provide a housing component for a hydraulic assembly with a recess on an inner surface in an area surrounding the through-hole, and to arrange the sealing element associated with the tie rod in the recess. In this way, the sealing element rests against an outer circumferential surface of the tie rod extending through the through-hole, against the inner surface of the housing component, and against a sealing surface of the tie rod nut, which is screwed to the tie rod inside the housing.

[0013] The recess on the inside of the housing part reduces the space required for the sealing element within the housing part. This allows for an increased stroke length for a component guided by the tie rod, such as a plain bearing in an actuating assembly of a brake booster, even when the sealing element is located inside the housing. Simultaneously, a hydraulic device mounted on the outside of the housing part on the tie rod can be replaced or removed and reinstalled without requiring the sealing element to be replaced. The sealing element thus provides a fluid-tight seal for the feedthrough opening, especially when the hydraulic device is removed, reinstalled, or replaced. The sealing element is therefore better protected against damage.

[0014] Advantageous designs and further developments result from the further sub-claims as well as from the description with reference to the figures in the drawing.

[0015] According to some embodiments, the through-opening may be circular and the recess may have a conical section.

[0016] According to some embodiments, the housing part may be deformed in the area surrounding the through-hole such that a recess is formed on the inner surface and a corresponding protrusion on the outer surface. For example, the housing part may have a substantially flat, particularly plate-shaped, cover section in which the through-hole is formed, wherein the cover section is deformed such that the area surrounding the through-hole forms a recess on the inner surface and a projection or protrusion on the outer surface. For example, the housing part, particularly the cover section, may be made of a sheet metal part, wherein the recess and the protrusion are produced by a press forming process. Optionally, the housing part may have a constant thickness in the area forming the recess and the protrusion.Providing a raised section in addition to the recess simplifies manufacturing and simultaneously increases the torsional rigidity of the housing component. Furthermore, a recess surrounding the bore can be formed on the flange of the hydraulic device, for example, in the form of a chamfer in which the projection is received.

[0017] According to some embodiments, the recess may have a depth in a range between 1 mm and 4 mm. In particular, the recess may have a depth in a range between 1.5 mm and 3.5 mm. Within this range, a noticeable increase in the stroke available at the tie rod is achieved, while at the same time the sealing element can be dimensioned relatively large, which further improves the sealing effect.

[0018] In some embodiments, the anchor nut may have an internal bore with an internal thread, which is screwed into an external thread formed on the inner section of the tie rod. The sealing surface of the anchor nut extends at least partially away from the end of the external thread facing the outer section of the tie rod. Thus, a portion of the sealing surface of the anchor nut, where the sealing element rests, is spaced away from the external thread of the tie rod. This provides even better protection for the sealing element against damage and further improves the sealing effect.

[0019] In some embodiments, the internal thread of the anchor nut may overlap the external thread of the tie rod by between 60 and 95 percent of the total thread length of the internal thread. This means the nut is screwed beyond the end of the tie rod's external thread, so that the end of the nut facing the outer section of the tie rod is spaced apart from the end of the external thread. This further ensures that the sealing element is not damaged by the anchor's external thread. Simultaneously, this overlap area creates a relatively large friction surface between the threads, facilitating an optional anti-rotation device for the anchor nut.

[0020] According to some embodiments, the inner bore may extend beyond the end of the external thread towards the outer section of the tie rod, and the sealing surface of the tie rod nut may be formed on the inner bore of the tie rod nut. For example, the tie rod nut may have an end face against the inner surface of the housing part, and the sealing surface provided in the inner bore may rest against the sealing element. This facilitates a defined positioning of the tie rod nut, and thus of the tie rod, relative to the housing part.

[0021] In some embodiments, the sealing surface of the anchor nut may be designed as a chamfer on the inner bore of the anchor nut. The angled extension of the sealing surface thus ensures that both an axial force (i.e., a force along the tie rod) and a radial force (i.e., a force perpendicular to the tie rod) are exerted on the sealing element. This further improves the sealing element's compression against the inner surface of the housing part and against the outer circumferential surface of the tie rod.

[0022] According to some embodiments, the anchor nut can be secured against rotation on the tie rod, particularly by a crimp connection. Accordingly, the method can include securing the anchor nut, which is screwed to the tie rod, against rotation on the tie rod. For example, the anchor nut can be provided with an external hexagon on its outer circumference, at least two, preferably three, of which sides are plastically pressed in radially to achieve plastic deformation of at least the internal thread, and optionally also the external thread, of the tie rod. This connection, referred to as crimping, offers the advantage that no additional component is required to secure the nut, while simultaneously creating reliable anti-rotation protection. Alternatively, other anti-rotation devices can also be provided.

[0023] According to some embodiments, the sealing element may be designed in an annular form. For example, the sealing element may be designed as an O-ring.

[0024] According to some embodiments, the hydraulic device may be designed in the form of a hydraulic pressure generating unit. For example, the hydraulic device may be a tandem master brake cylinder, a plunger, or the like.

[0025] The invention will now be explained with reference to the figures in the drawings. The figures show: Fig. 1 a schematic sectional view of a hydraulic assembly according to an embodiment of the invention; Fig. 2 a perspective view of an outer surface of a housing part of a housing assembly according to an embodiment of the invention; Fig. 3 a detailed view of the area marked by the letter X of the Fig. 1 hydraulic assembly shown; and Fig. 4 a flowchart of a method for manufacturing a housing assembly according to an embodiment of the invention.

[0026] In the figures, the same reference symbols denote identical or functionally equivalent components, unless otherwise stated.

[0027] Fig. 1 Figure 1 schematically shows a sectional view of a hydraulic assembly 200. The hydraulic assembly 200 comprises a housing assembly 100 and a hydraulic device 210. The hydraulic assembly 200 can, for example, be used as a component in an electromechanical brake booster for a vehicle, or such a brake booster can incorporate the hydraulic assembly 200.

[0028] The hydraulic device 210 is in Fig. 1 only partially shown, it has a flange 212 in which at least one bore 214 is formed. The hydraulic device 210 can, for example, be a hydraulic pressure generating device, such as a master brake cylinder, in particular a tandem master brake cylinder, a plunger, or the like. The hydraulic device 210 can, in particular, be mechanically actuated by means of an actuating assembly 220. The actuating assembly 220 is in Fig. 1 also only partially shown and can, as illustrated by example, have a connecting arm 221 and a sliding bearing 222 connected to the connecting arm 221. The connecting arm 221 can be linearly displaced by means of an electric motor (not shown), which is kinematically coupled to the actuating assembly, for example via a gearbox (not shown), in order to actuate the hydraulic device 210.

[0029] As in Fig. 1 As shown, the housing assembly 100 comprises a housing part 1, a tie rod 2, a tie rod nut 3 and a sealing element 4.

[0030] Housing part 1 is in Fig. 1 only partially shown. Fig. 2 Figure 1 schematically shows a perspective partial view of housing part 1. In general, housing part 1 defines or at least partially delimits an internal volume 10. As shown in the Fign. 1 and 2 As shown by way of example, the housing part 1 can, for instance, have a substantially flat or plate-shaped cover section 14 and a circumferential section 16 extending transversely to this. In general, the housing part 1 has an inner surface 1i facing the inner volume 10 or bounding the inner volume 10 and an outer surface 1a oriented opposite to this. As shown in the Fign. 1 and 2As further shown, the housing part 1 has a through-opening 11 extending between the inner surface 1i and the outer surface 1a of the housing part 1, which may be formed, in particular, in the cover section 14. The through-opening 11 may, in particular, have a circular circumference. Furthermore, a central connection opening 18 may be formed in the cover section 14, which extends between the inner surface 1i and the outer surface 1a of the housing part 1 and serves to accommodate an actuating interface of the hydraulic device 210. The housing part 1 may, for example, be made of a metal material, in particular a metal sheet. However, the invention is not limited to this.

[0031] As in Fig. 1 As shown, a region of the inner surface 1i surrounding the through-hole 11 forms a recess 12. The through-hole 11 is thus provided or arranged at the bottom or base 12B of a recess 12 formed on the inner surface 1i. As shown in the Fign. 1 and 3 As shown, the recess 12 can have a conical section 12A. The opening angle of the conical section 12A can, for example, be in a range between 70 degrees and 90 degrees. Optionally, the recess 12 can also have a substantially flat bottom section 12B in which the recess 12 is formed. As shown in Fig. 2 As shown by way of example, the housing part 1 can further have a raised area 13 on the outer surface 1a in the area surrounding the through-hole 11. As shown in Fig. 1 As shown schematically, the housing part 1 can thus be deformed such that a recess 12 is formed on the inner surface 1i and a corresponding, complementary elevation 13 is formed on the outer surface 1a. The recess 12 can, for example, have a depth t12 in a range between 1 mm and 4 mm ( Fig. 3 ).

[0032] The tie rod 2 is designed as a rod-shaped, elongated part extending along a longitudinal axis A2. As in Fig. 1 As shown, the tension anchor 2 runs within the inner volume 10 and extends through the through-opening 11. A portion of the tension anchor 2 located within the inner volume 10 forms an inner section 2A, while a portion of the tension anchor 2 defined by the outer surface 1a of the housing part 1 forms an outer section 2B of the tension anchor 2. The tension anchor 2 thus extends transversely to the cover section 14. The outer section 2B of the tension anchor 2 projects beyond the outer surface 1a of the housing part 1, in particular the cover section 14.

[0033] As in Fig. 1 As shown, the inner section 2A of the tie rod 2 can be inserted into one of the through-openings. 11The area facing the anchor 2 has an external thread 20. Furthermore, the tie rod 2 can have a guide section 22 on its inner section 2A, on which the sliding bearing 222 is guided linearly or slidably along the longitudinal axis A2. The outer section 2B of the tie rod 2 simultaneously forms an end section of the tie rod and can optionally also be provided with an external thread 24. As in Fig. 1 It can be seen that the outer section 2B can have a smaller diameter at least in some areas, especially in the area of ​​the thread 24, than the inner section 2A in the area of ​​the thread 20.

[0034] The anchor nut 3 is designed as a screwable sleeve. Accordingly, the anchor nut 3 has an internal bore 30 with an internal thread 31. Furthermore, the anchor nut 3 has a sealing surface 3a, which can be provided, for example, on the internal bore 30. As shown in the Fign. 1 and 3As shown by way of example, the sealing surface 3a can be designed as a chamfer 32 on the inner bore 30 of the anchor nut 3. The chamfer 32 thus defines a conical contact surface or sealing surface 3a, which can, for example, have an opening angle in a range between 100 degrees and 140 degrees. Optionally, the anchor nut 3 can also be provided with an external hexagon on its outer circumference.

[0035] As in Fig. 1 As shown schematically, the anchor nut 3 is screwed onto the external thread 20 of the tie rod 2 provided on the inner section 2A. Optionally, the anchor nut 3 can be secured against rotation on the tie rod 2, in particular by a crimp connection. For this purpose, the outer circumference of the anchor nut 3 can have at least one plastic deformation in the form of an indentation 34, which causes a plastic deformation 35 on the internal thread 31. As shown in Fig. 1 As further shown, the anchor nut 3 rests with an end face 3b against the inner surface 1a of the housing part 1.

[0036] As in Fig. 1 As further shown, the outer section 2B of the tie rod 2 projects through the bore 214 of the flange 212. To fix the flange 212 to the housing part 1, an external nut 216 can be provided, which is screwed to the external thread 24 of the outer section 2B of the tie rod 2 and clamps the flange 212 between itself and the housing part 1, in particular its cover section 14. Optionally, the external nut 216 can also be secured against rotation by a crimp connection to the tie rod 2. As shown in Fig. 1 As can still be seen, the flange 212 can have a recess 215 on a contact surface 212a facing the housing part 1 in an area surrounding the bore 214, in which the optional raised section 13 of the housing part 1 is received. However, the recess 215 can also be provided independently of the raised section of the housing part 1. The sealing element 4 can, in particular, be ring-shaped, e.g., as an O-ring, as shown in the Fign. 1 and 3 shown by way of example. As in Fig. 1 As shown, the sealing element 4 is arranged in the recess 12 on the inner surface 1i of the housing part 1 and thus surrounds the through-hole 11. Furthermore, the sealing element 4 encloses the inner section 2A of the tie rod 2 and is in contact with the sealing surface 3a of the anchor nut 3. As shown in particular in Fig. 3 As can be seen, the sealing element 4 thus rests in the recess 12 on the inner surface 1i of the housing part 1, on the outer circumferential surface of the tie rod 2, and on the sealing surface 3a of the anchor nut 3. The sealing element 4 therefore seals the through-hole 11 fluid-tight, e.g., against the escape of liquid from the inner volume 10 or against the ingress of liquid into the inner volume 10. The sealing element 4 is, in particular, squeezed or compressed between the sealing surface 3a of the anchor nut 3 and the area of ​​the inner surface 1i forming the recess 12. Fig. 3 The sealing paths that the sealing element 4 seals are indicated by the arrows P1, P2.

[0037] By arranging the sealing element 4 in the recess 12 on the side of the inner surface 1i of the housing part 1, the space required for the sealing element 4 within the internal volume 10 with respect to the longitudinal axis L1 is reduced. This allows the guide section 22 of the tie rod 2 to extend relatively close to the inner surface 1i of the housing part 1 or to the cover section 14 in the axial direction. Effectively, this increases the stroke, i.e., the distance that the sliding bearing 222 can travel on the tie rod 2. Furthermore, arranging the sealing element 4 in the recess 12 on the side of the inner surface 1i of the housing part 1 offers the advantage of providing good protection for the sealing element 4 against external influences. In particular, the hydraulic device 210 can be removed without damaging the sealing element 4 and / or without requiring replacement of the sealing element 4 when the hydraulic device 210 is re-flanged or a new hydraulic device 210 is installed.

[0038] As in the Fign. 1 and 3 As shown by way of example, the anchor nut 3 can be positioned relative to the tie rod 2 such that the sealing surface 3a of the anchor nut 3 extends at least partially spaced from an end of the external thread 20 facing the outer section 2B of the tie rod 2. As shown in Fig. 3 It can be seen, for example, that the inner bore 30 of the anchor nut 3, with its conical sealing surface 3a, can protrude beyond the end of the external thread 20 of the tie rod 2. This reliably prevents the sealing element 4 from being damaged by the external thread 20.

[0039] Fig. 4Figure 1 schematically illustrates the process of method M for manufacturing a housing assembly 100. Method M is explained below by way of example with reference to the housing assembly 100 described above. Method M comprises arranging M1 the sealing element 4 in the recess 12 of the housing part 1 and a step M2 in which the tie rod 2 is passed through the through-opening 11 of the housing part 1, in particular such that the external thread 20 and the guide section 22 are positioned in the inner volume 10 of the housing part 1. Steps M1 and M2 can be carried out, in particular, by sliding the sealing element 4 onto the tie rod 2 and positioning it in the recess by passing the tie rod 2 through the through-opening 11. Alternatively, however, the sealing element 4 can first be positioned in the recess 12 and the tie rod 2 then pushed through the sealing element 4 in step M2.

[0040] In a further step M3, the anchor nut 3 is screwed to the tie rod 2 as described above. The screwing step M2 can be performed before or after the tie rod 2 has been inserted through the feedthrough opening 11 (step M2).

[0041] Furthermore, step M4 is performed to contact the sealing element 4 with the sealing surface 3a of the anchor nut 3, the area of ​​the inner surface 1i surrounding the through-hole 11, and the inner section 2A of the tie rod 2. Step M4 can be performed simultaneously with steps M1 to M3. For example, the sealing element 4 can be contacted with the inner section 2A of the tie rod 2 during step M2. The sealing element 4 can be contacted with the sealing surface 3a of the anchor nut 3 and the area of ​​the inner surface 1i surrounding the through-hole 11, for example, by screwing it together in step M3.

[0042] Optionally, an additional step M5 can be provided in which the anchor nut 3 is fixed to the tie rod in a rotationally secure manner, e.g. by crimping.

[0043] Although the present invention has been explained above by way of example embodiments, it is not limited to these, but can be modified in many ways. In particular, combinations of the preceding embodiments are also conceivable.

Claims

1. Housing assembly (100) for a hydraulic assembly (200), having: a housing part (1), which at least partially delimits an internal volume (10) and has a feed-through opening (11) extending between an inner surface (1i) facing the internal volume (10) and an outer surface (1a) of the housing part (1) oriented in an opposite direction thereto, wherein a region of the inner surface (1i) surrounding the feed-through opening (11) forms a recess (12); a tie rod (2), which extends with an inner portion (2A) in the internal volume (10) of the housing part (1) and which projects through the feed-through opening (11) so that an outer portion (2B) of the tie rod (2) protrudes beyond the outer surface (1a) of the housing part (1); an anchor nut (3), which is screwed onto the inner portion (2A) of the tie rod (2) and has a sealing surface (3a); and a sealing element (4), which is arranged in the recess (12) and bears on the inner portion (2A) of the tie rod (2), on the region of the inner surface (1i) surrounding the feed-through opening (11), and on the sealing surface (3a) of the anchor nut (3).

2. Housing assembly (100) according to Claim 1, wherein the housing part (1), in the region surrounding the feed-through opening (11), is deformed in such a way that the recess (12) is formed on the inner surface (1i) and a corresponding elevation (13) is formed on the outer surface (1a).

3. Housing assembly (100) according to Claim 1 or 2, wherein the recess (12) has a depth (t12) in a range between 1 mm and 4 mm.

4. Housing assembly (100) according to any one of the preceding claims, wherein the anchor nut (3) has an inner bore (30) with an inner thread (31) which is screwed onto an outer thread (20) formed on the inner portion (2A) of the tie rod (2), wherein the sealing surface (3a) of the anchor nut (3) extends at least partially spaced apart from an end of the outer thread (20) facing the outer portion (2B) of the tie rod (2).

5. Housing assembly (100) according to Claim 4, wherein the inner bore (30) protrudes in the direction of the outer portion (2B) of the tie rod (2) beyond the end of the outer thread (20), and the sealing surface (3a) of the anchor nut (3) is formed on the inner bore (30) of the anchor nut (3).

6. Housing assembly (100) according to Claim 5, wherein the sealing surface (3a) of the anchor nut (3) is formed as a chamfer (32) on the inner bore (30) of the anchor nut (3).

7. Housing assembly (100) according to any one of the preceding claims, wherein the anchor nut (3) is rotationally secured on the tie rod (2), in particular by a crimp connection.

8. Housing assembly (100) according to any one of the preceding claims, wherein the sealing element (4) is annular, in particular formed as an O-ring.

9. Hydraulic assembly (200), in particular for a hydraulic brake system, having: a housing assembly (100) according to any one of the preceding claims; and a hydraulic device (210), in particular in the form of a pressure generator, having a flange (212) on which a bore (214) is formed; wherein the outer portion (2B) of the tie rod (2) extends through the bore (214) of the flange (212), and the hydraulic device (210) is fastened to the housing assembly (100) via the tie rod (2).

10. Method (M) for producing a housing assembly (100) according to any one of Claims 1 to 8, comprising: arranging (M1) the sealing element (4) in the recess (12) of the housing part (1); feeding (M2) the tie rod (2) through the feed-through opening (11) of the housing part (1); screwing (M3) the anchor nut (3) onto the tie rod (2); and contacting (M4) the sealing element (4) with the sealing surface (3a) of the anchor nut (3), with the region of the inner surface (1i) surrounding the feed-through opening (11), and with the inner portion (2A) of the tie rod (2).