Housing block, method for producing a housing block and core

Abstract

A housing block, a method for producing such a housing block and a sand core for use in such a method are disclosed, wherein a channel with a slotted hole or flat channel geometry is formed within the housing block.

Description

Technical Field

[0001] The invention relates to a housing block, a method for producing the same and a core that can be used during production. Background Art

[0002] For more complex control and regulation tasks in hydraulic systems, the required hydraulic components are usually implemented in valve blocks, which are either designed as plate structures or designed in a monoblock construction. Control blocks designed in a monoblock construction are particularly used in automotive hydraulic systems.

[0003] In this case, individual components, such as valves and pressure medium connections required for control and regulation, are accommodated in the housing block, and pressure medium ducts required for conducting the pressure medium are formed in the housing block.

[0004] In conventional production of such housing blocks, a semi-finished product (casting block), which is produced, for example, by casting, is machined and the pressure medium duct is designed as a cylindrical bore by means of conventional bores.

[0005] DE 10 2006 062 373 A1 describes a control block produced according to a generative manufacturing method. In this generative method, the component to be produced is formed in layers from amorphous or form-neutral materials (e.g. sintered materials) using physical and / or chemical effects. In the SLM method (selective laser melting), for example, metal powder is applied in layers and the layers are melted by means of a laser and fused to the underlying layers, so that complex geometries can also be formed, which have internal fine grooves.

[0006] The method described in DE 10 2006 062 373 A1 focuses on minimizing the weight of the control block. Accordingly, the channels and the receptacles (valve bores) required for connecting the hydraulic components are provided with a wall thickness corresponding to the load and, if necessary, also with reinforcing elements forming a reinforcing structure, thereby forming a self-supporting structure which forms the channels and has a relatively thin wall thickness. The problem with this lightweight design is that a control block constructed in this way cannot withstand high pressure loads or large external mechanical loads.

[0007] Especially when forming channels by means of holes, the problem is that the channel structure of the control block is basically formed by the interlacing of individual cylindrical channel holes with valve and component holes. These interlaced / connecting areas are then often limited by the blocking areas that cannot be drilled on the corresponding valve or hydraulic component.

[0008] Accordingly, the maximum achievable flow area of ​​the cylindrical hole / channel structure is also limited, so that at high pressure medium volume flows, relatively high pressure losses can occur. Summary of the invention

[0009] In contrast, the object of the present invention is to specify a housing block and a method for producing the same, in which a flow-optimized channel structure can be formed with little outlay in terms of device technology.

[0010] This object is achieved with respect to the housing block by the solution according to the invention and with respect to the method by the parallel solution according to the invention. In addition, this object is also achieved with a core that can be used in the method according to the invention.

[0011] Advantageous developments of the invention are the subject matter of preferred embodiments.

[0012] The housing block designed in a monolithic manner according to the invention has at least one receptacle for a hydraulic component, such as a valve. The receptacle is fluidically connected to other receptacles and / or inlet or outlet connections of the housing block via at least one connecting channel, wherein the channel opens into the receptacle within the housing block. According to the invention, the channel is designed at least in sections as a flat channel or with an elongated hole geometry.

[0013] The design of the internal geometry of the channel with a slotted hole or flat channel geometry extending between the receptacle and, if appropriate, the inlet or outlet line channel has the advantage that the average cross section of the connecting channel is increased while complying with limiting factors, such as the barrier regions of valves or other hydraulic components mentioned in the introduction, and thus reducing pressure losses at high pressure medium volume flows. In addition, the formation of cavitation can be prevented or at least minimized by the increased flow cross section.

[0014] In a particularly preferred embodiment, the housing block or the core for forming the channel structure is produced by a generative method.

[0015] This generative manufacturing method makes it possible to design the shape of the inlet or outlet channels and connecting channels almost arbitrarily, compared to conventional technologies, such as using 3D printing technology or the SLM method mentioned in the introduction. In conventional technologies, the channels must be formed by straight or inclined cylindrical holes.

[0016] A further advantage of the generative method is that the desired geometry of the channel structure can already be introduced within the housing block during the casting process.

[0017] In one variant of the invention, the core is designed as a 3D-printed sand core. By increasing the cross section of the sand core due to the elongated hole or flat channel geometry, the stability of the sand core is improved compared to conventional sand cores with a cylindrical cross section.

[0018] As mentioned at the outset, it is however also possible according to the invention to produce the housing segment itself by a generative method without using a core.

[0019] In a preferred solution, the maximum width of the channel cross section is a multiple of the height of the relevant cross-sectional area, so that on the one hand the stability of the structure is further improved and on the other hand the flow cross section is further optimized.

[0020] In an advantageous manner, the passage opens roughly radially into the circumferential surface of the receiving portion, or roughly axially into the bottom surface or the annular surface of the receiving portion. Alternatively, the passage can also intersect the receiving portion roughly tangentially, so that the passage extends on the receiving portion when viewed in the flow direction, and does not completely open into the receiving portion.

[0021] In this solution it is particularly preferred if the inlet region widens into the flat channel so that the inlet region extends over a larger circumferential section than the region of the channel adjoining the flat channel section.

[0022] In one embodiment, the channel can be curved according to the circumference of the receptacle, wherein the channel opens, for example as a flat channel, approximately axially into the bottom surface or annular surface of the receptacle, so that wall sections of the channel and of the circumferential wall extend approximately in parallel directions.

[0023] According to one embodiment, the inlet region is designed in such a way that it extends over more than 90°, preferably more than 120°, of the circumferential region of the receptacle.

[0024] If an annular channel is formed in this area or in other areas of the receptacle, the flow into or out of the receptacle can be further improved. Such an annular channel forming an undercut cannot be produced by mechanical processing or can only be produced very laboriously.

[0025] In the method for manufacturing a housing block, a core designed according to a channel structure is first manufactured by a generative method, wherein the section of the channel structure located inside is designed as a flat channel. In a subsequent method step, the core is placed in a casting mold and the housing block is cast.

[0026] After this casting process, the core is removed from the housing block, so that the channel structure is formed without requiring any subsequent machining, or requiring subsequent machining only in the region of the joints.

[0027] In this case, it is preferred that the core is designed as a 3D-printed sand core.

[0028] In an alternative method, the housing segment is produced directly using a generative method, for example the SLM method described in the introduction. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] An exemplary embodiment of the present invention is described in more detail below with reference to schematic diagrams.

[0030] Figure 1 A view showing a housing block made by a casting method;

[0031] Figure 2 The 3D-printing method is used to manufacture Figure 1 Sand core of the shell block;

[0032] Figure 3 Shown according to Figure 2 A partial view of a sand core of FIG. 1 and showing a region of a housing block constructed with the aid of the sand core;

[0033] Figure 4 Shown according to Figure 1 Another area of ​​the housing block, which is formed by Figure 2 Sand core structure;

[0034] Figure 5 A partial view of a housing block is shown, wherein an annular channel is formed in the inlet region of the channel in a receptacle for a valve;

[0035] Figure 6 Shown along Figure 5 The section of line AA in;

[0036] Figure 7 Shown according to Figure 6 Variations of channel guides;

[0037] Figure 8 Shown according to Figure 5 A variation of the embodiment of

[0038] Fig. 9 Shown along Figure 8 The section of line AA in;

[0039] Fig.10 Shown according to Fig. 9 Variations of the channel trend;

[0040] Fig.11 Shown along Fig.10 The section of line BB in;

[0041] Fig.12 A partial view of a housing block is shown, wherein an annular channel is formed in the receptacle;

[0042] Fig.13 Shown along Fig.12 The section of line AA in;

[0043] Fig.14 Shown according to Fig.12 A variant of an embodiment in which an annular channel is constructed in the region of the radial joint and the control joint;

[0044] Fig.15 Shown along Fig.14 A section through line AA in FIG. 1 ; and

[0045] Fig.16 Shown along Fig.15 Line BB in. DETAILED DESCRIPTION

[0046] The design and production of a housing block for a control block is described with reference to the following figures, which is produced by a casting method or according to a generative production method (additive manufacturing), so that channels for conducting pressure medium are formed between valves accommodated in the control block and other hydraulic components without the need for drilling holes, etc.

[0047] Figure 1 Here, a casting of such a housing block 1 is shown, in which a plurality of receptacles for valves or other hydraulic components open into the side surfaces. Figure 1 In the drawing, three of the receptacles which in principle form the valve opening are provided by way of example with the reference numerals 2 , 4 , 6 .

[0048] Figure 2 A core produced using a generative method is shown, which in this specific embodiment is designed as a sand core 8 produced using a 3D printing method. The sand core 8 forms pressure medium channels, via which the inlet and outlet connections of the control block are hydraulically connected to the hydraulic components required for actuating one or more consumers, such as valves accommodated in the receptacles 2, 4, 6. Figure 1 The receiving parts 2, 4, 6 highlighted by way of example are formed by the end sections of the core branches 10, 12, 14, which in turn are connected by channel-forming core sections 16, 18, 20. The channel section 18 extends approximately in the axial direction toward the end section 22 of the core branch 10 forming the receiving part 2. This core section 18 is provided with a circular cross section, so that a corresponding channel structure is also formed.

[0049] The core section 18, which is designated by reference numeral 16, is designed as a flat profile, so that the resulting channel has a correspondingly long hole or flat channel geometry. This core section 18 intersects tangentially, for example, with the end sections 22 and 23 of the core branches 10, 14, so that the correspondingly formed channel is located between the two receptacles 2, 6 and Figure 1A pressure medium connection is produced between further components of the housing block 1 shown in FIG. 1 , which are situated downstream or upstream of this channel.

[0050] according to Figure 2 In the figure, a plurality of such cylindrical or flat core segments are provided, which each form a channel segment extending between the individual receptacles. For understanding the invention, it is not necessary to describe the specific course of the core segments and thus the detailed structure of the sand core. It is important to emphasize according to the invention that at least some of the core segments are provided with the described flat profile, so that during casting, corresponding internal channel segments are formed.

[0051] Figure 3 The region of the sand core 8 forming the core branch 10 is shown. In this figure, the end section 22 of the sand core branch 10 forming the receptacle 2 can be seen. In the transition region of this end section 22 to the core section 18, an annular projection 24 is formed which is widened in the radial direction relative to the end section 22.

[0052] During casting, a corresponding gap is then formed by the end section 22 Figure 3 The center right side shows a receptacle 2 in which, in the transition region to the inlet channel 28 formed by the core section 18, the annular projection 24 forms an annular channel 30 which opens axially into the receptacle 2. This construction will be described in more detail below.

[0053] The core section 16 having a flat profile—as described above—intersects the end section 22 approximately tangentially, so that Figure 3 As shown in the middle right, an elliptical slot-shaped inlet 31 is formed in the circumferential region of the receptacle 2. The inlet extends over a relatively large circumferential region, wherein, depending on the course of the core section 16 designed as a flat profile, a circumferential region of more than 120° can be covered by the inlet 31. Accordingly, by appropriately selecting the flat profile and course of the corresponding core section, the corresponding inlet region of the channel can be optimized in terms of flow technology, so that the pressure medium flows to and from the valve or to and from the hydraulic component with minimal pressure loss.

[0054] Figure 4 A variant is shown in which a core section provided with a flat profile opens axially, for example, on the bottom surface 33 of the receiving portion 32. In this embodiment, the core section is designed as a curved flat profile, thereby correspondingly producing a kidney-shaped inlet 34, the curvature radius of which is selected so that it extends parallel to and spaced apart from the circumferential wall of the receiving portion, thereby again ensuring an optimized inflow or outflow relationship. Of course, the kidney-shaped, curved inlet can also be inclined relative to the circumferential wall.

[0055] Will use Figures 5 to 16Some possible variations of the design of these entrance areas are presented.

[0056] Figure 5 A section of a housing block 1 is shown by way of example, in which a receptacle 2 forming a valve bore is constructed in the manner described above. This receptacle 2 - as is common for valve bores - is constructed as a stepped bore, into which a pressure limiting valve 36 designed in a bullet-shaped manner can be inserted, for example. The basic structure of such a valve is known, so a description thereof is omitted. An inlet channel 28 formed by an axial core section opens into the receptacle 2. In the Figure 5 In the embodiment, the outflow channel 40 opens into the receiving portion 2 in the radial direction above the inlet channel and controls the oil channel 42 again opens into the receiving portion in the radial direction above the outflow channel. In the illustrated embodiment, these channels 38, 40, 42 are each configured with a circular cross section. In the inlet region of the outflow channel 40, an annular channel 30 formed according to the above-mentioned design is configured, into which the radially extending outflow channel 40 flows in an optimized manner.

[0057] Figure 6 Shown along Figure 5 . In this figure, the schematically shown valve 36 inserted into the receptacle 2 (valve bore) can be seen. In the inlet region of the radially extending outflow channel 40, an annular channel 30 is formed, which surrounds the valve 36 in the region of the outlet connection on the discharge side, so that the pressure medium can flow out with minimal pressure loss in accordance with the pressure limiting function of the valve 36. In this embodiment, the height h of the outflow channel 40 in the inlet region corresponds to the diameter of the annular channel 30.

[0058] Figure 7 Show according to Figure 5 A variation of the embodiment. In this embodiment, the annular channel 36 is also constructed in the inlet area of ​​the outflow channel 40. However, the outflow channel 40 does not radially open into the receiving portion 2 (valve hole), but intersects with the receiving portion tangentially, so that a pressure medium connection is generated with the annular channel 36, and the channel branch 44 further extends to the outflow connection of another valve, to the pressure medium tank or to other components. Figure 6 As shown in FIG. 4 , the diameter or width of the outflow channel 40 is smaller than the diameter of the annular channel 30 .

[0059] Of course, such a channel structure can also be formed in the region of the inflow channel 38 or the control oil channel 42 .

[0060] In the above-described exemplary embodiments, the channels 40 , 44 are preferably designed as flat channels at least in the inlet region, and this structure will be described in more detail below.

[0061] Figure 8 Show according to Figure 5 A variant of the embodiment of , in which the outflow channel 40 again opens radially.

[0062] In this embodiment, according to Figure 8 , and according to Fig. 9 In the cross-sectional view in FIG. 1 , the outflow channel 40 is also configured as a flat channel, which is perpendicular to the Figure 8 The width B of the viewing angle extension in Fig. 9 ) is greater than Figure 8 The height h visible in Fig. 9 , which width B is also greater than the diameter of the valve in this region, wherein the flat channel (outflow channel 40) extends over the circumference of the valve 36, so that according to Fig. 9 In principle - if the installation space and the valve design permit - in the inlet region the height h can also correspond to the width B, so that a channel with a circular cross section is also formed, which also extends over the valve 36.

[0063] Fig.10 Shows the corresponding Figure 7 A variant in which the outflow channel 40 also intersects the receptacle 2 radially and extends with a channel branch 44 through the receptacle 2 or the valve 36 to the next component. In this case, the annular channel 30 is then - just as according to Figure 7 In the embodiment of FIG. 4 , the circumference extends only over a portion of the circumference. In the case where the channel branch 44 is not bent relative to the outflow channel 40, the circumferential range is approximately 180°. Figure 7 In the exemplary embodiment of FIG. 4 , the circumferential extent is correspondingly larger, since the channel branch 44 is angled relative to the outflow channel 40 .

[0064] Fig.11 Shown along Fig.10 BB in FIG. In this figure, the narrowed channel cross section 48 in the transition region between the outflow channel 40 and the channel branch 44 and the annular channel 30 extending backwards over a portion of the circumference of the valve 36 can be seen.

[0065] Fig.12 and 13 An exemplary embodiment is shown in which an annular channel 30 is formed axially spaced apart from the inlet channel 28 and which is arranged according to Fig.13 The cross-sectional view in FIG. 1 encompasses the entire circumference of the valve 36. The annular channel 30 can then be connected to a pressure medium tank or other components via a channel (not shown).

[0066] With the help of Figures 14 to 16An embodiment will be described in which a surrounding annular channel 30 is also formed in the region of the outflow channel 40, into which the outflow channel 40 opens. Fig.15 In the cross section, it can be seen that in this embodiment, the outflow channel 40 is configured with an expansion portion 50 toward the annular channel 30, and the expansion portion is designed, for example, so that the outflow channel 40 is Fig.14 In the lower region, it opens approximately tangentially into the annular channel 30 and in Fig.15 The expansion portion 50 is located in the upper region and enters the annular channel 30 through the rounded portion. Of course, the expansion portion 50 can also be configured in other ways. Through the expansion portion 50, the pressure medium flows out of the valve 36 (or flows into the valve) further.

[0067] Fig.16 Show Fig.15 BB cross section in . Accordingly, a straight or curved outflow channel 40 is also designed as a flat channel (or with an elongated hole geometry), wherein the width B is significantly greater than the height h.

[0068] In addition Fig.14 In the exemplary embodiment shown, a further annular channel 52 is also formed in the circumferential wall of the receptacle 2 in the region of the control oil channel 42 , into which the control oil channel 42 then opens according to the previous exemplary embodiments, so that the control oil guidance is also optimized.

[0069] A housing block, a method for producing such a housing block and a sand core which can be used in such a method are disclosed, wherein channels with elongated hole or flat channel geometry are formed within the housing block.

Claims

1. A housing block having at least one receptacle (2, 4, 6) for accommodating a hydraulic component, the receptacle being hydraulically connected to other receptacles (2, 4, 6) and / or inflow or outflow channels (38, 40) of the housing block via a connecting channel, wherein: The connecting channel opens into the receptacle (2, 4, 6) within the housing block and is characterized in that the connecting channel is at least partially designed as a flat channel with an increased average cross section, wherein the width (B) of the flat channel cross section is a multiple of the height (h) of the flat channel cross section.

2. The housing block according to claim 1, wherein: The housing block or the core for forming the connecting channel structure during the casting process is produced according to a generative method.

3. The housing block according to claim 2, wherein: The core is a sand core (8) made by a 3D-printing method.

4. The housing block according to claim 1, wherein: The connecting channel opens approximately radially into the circumferential surface of the receptacle (2, 4, 6), or approximately axially into the bottom surface or the annular surface (33), or intersects it in an approximately tangential manner.

5. The housing block according to claim 4, wherein: At least one inlet region widens into the flat channel, so that it extends over a larger circumferential section of the receptacle than a region adjoining the flat channel.

6. The housing block according to claim 5, wherein: The flat channel opens approximately axially and is curved according to the circumference of the receptacle (2, 4, 6).

7. The housing block according to claim 5, wherein: The circumferential section extends over more than 90°.

8. The housing block according to claim 5, wherein: The circumferential section extends over 180° and more.

9. The housing block according to claim 5, wherein: An annular channel (30, 52) is formed circumferentially or partially on the circumferential wall of the receptacle in the inlet region.

10. The housing block according to claim 9, wherein: The flat channel opens into the annular channel (30, 52).

11. A method for producing a housing segment according to any one of the preceding claims, comprising the following steps: - the core and the receiving parts (2, 4, 6) connected to the connecting channel structure of the housing are manufactured by a generative method according to the connecting channel structure of the housing, wherein: The section of the connecting channel structure located inside is designed as a flat channel. - casting the shell block in a casting mould containing the core, and - Remove the core from the cast shell block.

12. The method for producing a housing segment according to claim 11, wherein: The core is a sand core (8) made by a 3D-printing method.

13. A method for producing a housing segment according to any one of claims 1 to 10, wherein: A housing block is produced by a generative method, the housing block having a connecting channel structure and a receiving portion (2, 4, 6) connected thereto.

14. The method for producing a housing segment according to claim 13, wherein: The housing block is produced using the SLM method.

15. A sand core for use in the method according to claim 12, characterized in that: The sand core (8) is manufactured using a generative method.

16. The sand core according to claim 15, characterized in that The sand core (8) is manufactured by 3D-printing.

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