Control board for hydraulic machine

Abstract

The invention relates to a control plate (18) configured to fit a hydraulic machine (e.g., an axial piston machine or a pressure exchanger) for hydraulic fluid, the control plate (18) comprising a body (21) having an arrangement of passage openings (22, 23) for the passage of the hydraulic fluid and a contact surface, the entire thickness of the body (21) is formed from a primary material, wherein the primary material is a first polymeric material. It is an object of the present invention to provide a control board (18) having a good lifetime. This object is solved by a control plate (18) wherein the main body (21) comprises at least one differential section made of a second polymeric material (31) wherein the second polymeric material (31) is different from the main material.

Description

Technical Field

[0001] The present invention relates to a control panel configured to assemble a hydraulic press (e.g., an axial piston press or a pressure exchanger), wherein the control panel includes a body having an arrangement of channel openings for allowing hydraulic fluid to pass through and contact surfaces, wherein the body (the entire thickness) is formed of a first (e.g., a polymer) material.

[0002] Furthermore, the present invention relates to a hydraulic press, and to a method for manufacturing a control panel. Background Technology

[0003] In rotary hydraulic presses, the control panel is used as a port plate or valve plate.

[0004] For example, a hydraulic press may be in the form of an axial piston press, wherein the cylinder drum is rotatably arranged in a housing and includes multiple cylinders. When the hydraulic press is used as a motor, the cylinders are fluidly connected to a supply of pressurized hydraulic fluid, while other cylinders are connected to a return line. The control panel includes an arrangement of channel openings, for example having at least two kidney-shaped channel openings, one connected to the supply of pressurized hydraulic fluid and the other connected to the return line.

[0005] This invention is also applicable, for example, to hydraulic presses used as pumps.

[0006] In most cases, oil is used as the hydraulic fluid. Oil has lubricating properties. In other cases, the hydraulic fluid is water. Regardless of the hydraulic fluid, cavitation can occur during the operation of a hydraulic press, and this cavitation can damage the control panel, especially its surface. Once the surface erosion caused by cavitation becomes too severe, the control panel needs to be replaced. Summary of the Invention

[0007] The purpose of this invention is to provide a control board with a long service life.

[0008] This objective is achieved by the control board according to claim 1.

[0009] The body is formed of a first material. The first material of the body may be a first polymeric material. The body includes at least one (differentiated) portion made of a second material (e.g., a second polymeric material), wherein the second material is different from the first material (e.g., the first polymeric material). The body may include several (i.e., at least two) differentiating segments formed of the second polymeric material.

[0010] Except for one or more sections formed of the second (polymer) material, the entire body of the control panel may be formed of the first (polymer) material. In particular, the entire thickness of the body may be formed of the first polymer material (with no differentiating sections located therein). The second (polymer) material is arranged in one or more differentiating sections.

[0011] According to one aspect, (one or more) differential sections can be arranged where damage due to cavitation is typically observed, especially if a first (polymer) material is used instead of a second (polymer) material there.

[0012] Different types of materials have different properties. For example, a first material (a first polymer material) may include good frictional properties and / or good structural properties (such as strength, especially with respect to its specific gravity). A second material (e.g., a second polymer material) may exhibit good cavitation damage recovery properties.

[0013] In particular, the cavitation damage recovery properties of the second material (e.g., the second polymer material) can be higher than those of the first material (the first polymer material). As a result, each part of the control board can be optimized based on the actual load (e.g., friction, cavitation, abrasion, etc.) within certain sections.

[0014] According to one aspect, the control plate can be adapted to engage mating parts of a hydraulic press, such as the pressure plate of the hydraulic press. More specifically, contact surfaces can be adapted to engage mating parts of the hydraulic press. The contact surfaces can be configured to slide against the mating parts during operation. The abutment can be at least substantially sealed.

[0015] The control board can be adapted to form part of a hydraulic press with rotating elements. For example, the control board can be a port plate / valve plate for a hydraulic press with rotating elements.

[0016] The mating parts can be, for example, the pressure plate and / or cylinder of a hydraulic press.

[0017] The contact surface can be (at least substantially) arranged perpendicular to the axial direction of the control plate. The axial direction can be parallel to (or even coincide with) the relative axis of rotation between the control plate and the mating component.

[0018] The contact surface can be one end of the control panel along the axial direction of the control panel.

[0019] The control panel can have a basic disc-shaped form.

[0020] For example, the first material (first polymer material) can be combined with its mating parts to have good tribological properties. For example, the mating parts can be formed of stainless steel and / or ceramic. The second (polymer) material can be disposed within one or more differential sections of the body at locations susceptible to cavitation, thereby keeping wear / damage caused by cavitation low. Furthermore, for example, a third polymer material can be provided in another area that may be easily subjected to abrasive grinding, wherein the third material is robustly resistant to such abrasion. This allows the control plate to have a good lifespan.

[0021] According to one aspect, one, several, or all of the channel openings can be annular and / or kidney-shaped. This allows for good control of fluid flow between the channel openings and the mating member. In operation, the mating member can rotate relative to the control plate, thereby sliding against the contact surface. Due to the relative rotation, the fluid openings arranged in the mating member (especially in the mating surface of the contact surface of the engagement control portion) can intermittently come into fluid contact with the channel openings of the control plate.

[0022] In one embodiment, at least one differential section extends at least partially along the surface of the control panel. In particular, at least one differential section may extend at least partially along the contact surface of the control panel. The contact surface is particularly susceptible to cavitation damage. Naturally, all differential sections may extend at least partially along the surface of the control panel, especially along the contact surface.

[0023] In embodiments of the invention, the first polymer material is a fiber-reinforced polymer. This material can be, for example, a carbon fiber-reinforced polymer, particularly a carbon fiber woven composite. This material has good strength, allowing the hydraulic press equipped with this control panel to operate at high hydraulic pressure.

[0024] In embodiments of the invention, the control panel includes a circular sliding track (referred to as the sliding track) at the contact surface, wherein at least one channel opening is arranged in the sliding track, and a second (polymer) material is disposed within the circular sliding track. In other words, at least one differential section is arranged in the sliding track. In this case, at least one differential section provided with the second (polymer) material is arranged within the circular sliding track. During operation, portions of the circular sliding track can withstand cavitation. In particular, these portions can be fitted with the second (polymer) material, which is capable of withstanding cavitation better than the first (polymer) material. This achieves a long service life for the control panel.

[0025] One, several, or all of the channel openings can be arranged in a sliding track.

[0026] The channel openings may be open at the contact surface. For example, each channel opening may have at least one first open end at the contact surface (especially in a sliding track) and at least one second open end at a location away from the contact surface (e.g., at the end face of the control plate opposite to the contact surface in the axial direction).

[0027] In embodiments of the invention, the contact surface comprises a circular sliding track, and the surface of the contact surface is smoother in the area within the sliding track than in the area outside the sliding track. In this case, not the entire contact surface, but only the (differentiated) sliding track, can be used to contact the mating part. If the sliding track is particularly smooth, friction can be reduced and thus wear can be reduced.

[0028] The circular sliding track can extend along a circular direction (e.g., about the disc shape of the control panel, the axial direction, and / or around the relative axis of rotation).

[0029] In embodiments of the invention, a second (polymer) material is arranged at least (respectively) along a circular direction between adjacent channel openings, for example, at contact surfaces. For example, the second (polymer) material may be arranged at least, respectively, between the end regions of the channel openings (e.g., kidney-shaped channel openings). The end regions of the channel openings refer to the ends of the channel openings that are closest to each other, for example, along a circular direction. As described above, in operation, one of the channel openings can be subjected to a high-pressure supply, while the other channel opening can be fluidly connected to a return line. This results in a high pressure differential between the two channel openings. By providing a second (polymer) material between the end regions of the channel openings, the second material is positioned within a region highly subjected to cavitation. The second (polymer) material has better cavitation handling characteristics than the first (polymer) material, allowing the second (polymer) material to withstand cavitation in a favorable manner, thereby extending the life of the control panel.

[0030] In embodiments of the invention, the circular sliding track is raised relative to the surface adjacent to it (i.e., compared to the rest of the contact surface). At least one of the channel openings can be arranged within the raised circular sliding track. By making the circular sliding track raised relative to the adjacent surface, a high surface pressure can be applied to the circular sliding track, thereby providing a good seal when engaging with the mating parts of the hydraulic press (e.g., with the cylinder of the hydraulic press). This portion also experiences the most cavitation and friction. Therefore, providing a second material within this portion results in a good service life. In particular, the raised sliding track can be formed at least in the portion along the circular direction, wherein the ends of the channel opening(s) for high fluid pressure are located at the contact surface.

[0031] A circular sliding track can extend entirely along a circular direction. However, it can also be formed intermittently along a circular direction. For example, the sliding track may not be formed (or at least not raised) along a complete circular direction. In some portions along the circular direction, the sliding track may not be formed or at least not raised. For example, in the annular portion at the end of the channel(s) opening for low fluid pressure located at the contact surface, the sliding track may be interrupted (not formed) or at least not raised.

[0032] In embodiments of the invention, the second material is at least partially disposed in a recessed section of the body. For example, the recessed section may be rectangular, annular, or circular in shape. By providing the second material in the recessed section that is recessed relative to adjacent surfaces, the second material is securely fixed to the body. Furthermore, the surfaces of the second (polymer) material and the first (polymer) material can (at least partially) be adapted to each other, such that, for example, a continuous flat surface is created on a sliding track without channel openings. This results in good frictional properties and a good seal.

[0033] In one embodiment, the recessed section has at least one undercut, which allows the second (polymer) material to be mechanically locked to the body. This improves the reliable fixation of the second (polymer) material to the body.

[0034] In embodiments of the invention, the thickness of the differential segment is greater than 0.1 mm and / or less than 3 mm, preferably less than 2 mm, or the segment extends through the thickness of the control plate. The thickness can be measured (at least substantially) in a direction parallel to the relative axis of rotation, for example, along the axial direction. In the first case, where the thickness of the segment is greater than 0.1 mm and less than 3 mm, preferably less than 2 mm, the segment of the second material forms a layer on the body. In the second case, the second material replaces a portion of the first material in the thickness direction of the body. Either case is preferred depending on the characteristics of the hydraulic press. The first case is suitable for high pressure, while the second case allows for greater wear. Therefore, a suitable case can be selected for the corresponding characteristics.

[0035] The second (polymer) material can be a reinforcing material. According to one aspect, it can be reinforced with elongated reinforcing particles. The elongated reinforcing particles can include / are composed of chopped fibers (e.g., chopped carbon fibers and / or chopped glass fibers), nanotubes, and / or any kind of short, elongated components that modify the properties of the second material.

[0036] In embodiments of the present invention, the second (polymer) material includes a microstructured surface.

[0037] In the case of a fiber-reinforced second material, elongated reinforcing particles (e.g., small, chopped carbon fibers) are arranged in a specific orientation in the surface layer, such that the elongated reinforcing particles are arranged in parallel, helical, annular, circular, or diamond-shaped (rhomboid) patterns. This results in good cavitation resistance while minimizing any potential impact on the low-friction properties of, for example, the first material. For example, additive manufacturing can be used to deposit the second (polymer) material in a desired shape. In this application, additive manufacturing relates to methods for depositing materials (e.g., polymer materials) in desired 2D and / or 3D shapes. This includes 3D printing. This allows for good flexibility in surface design.

[0038] In embodiments of the invention, the second polymer material is PEEK or PEEK comprising one or more filler materials. The filler material is elongated reinforcing particles (such as chopped short carbon fibers), ceramic particles, etc., to name just a few examples. The filler material can be selected based on hydraulic fluid, frictional characteristics, etc.

[0039] In embodiments of the invention, the first (polymer) material includes properties that reduce friction. In this case, the hydraulic press can be used in conjunction with water as the hydraulic fluid.

[0040] In embodiments of the invention, the first (polymer) material is reinforced with fibers having a length of at least 5 mm. The longer the fibers, the more stable the control plate. In the prior art, the coating applied to the steel core of the control plate is typically produced by injection molding. During injection molding, the fibers used to reinforce the polymer material are shortened in the extruder, such that the fiber length is typically limited to less than 1 mm. Therefore, a fiber length of at least 5 mm gives the control plate considerable strength.

[0041] In embodiments of the invention, at least in the thickness region adjacent to the contact surface, more than 50% of the fibers comprise an angle of less than 30° to the contact surface. Therefore, the fibers are more or less parallel to the contact surface (in other words, the fibers are arranged substantially perpendicular to the axial direction), such that the mating member of the control plate runs substantially parallel to most of the fibers and does not slip on the surface roughened by the fiber ends. Thus, frictional contact is in its optimal form. The predominantly parallel orientation of the fibers in the first (polymer) material means that the contact area between the fibers and the mating member is greater. This will also improve the wear resistance of the control plate.

[0042] In embodiments of the invention, the fibers of the first (polymer) material are arranged in layers. In other words, the fibers are arranged in a plane that is substantially parallel to each other and substantially parallel to the contact surface. Therefore, the fibers reinforce the control plate in the direction parallel to the contact surface, and thus in the direction where higher strength and stiffness are desired. Lower stiffness is advantageous in the direction perpendicular to the contact surface because the control plate can exhibit some elastic properties in this direction to suppress noise.

[0043] In embodiments of the invention, layers of a first (polymer) material and / or a second (polymer) material are stacked in a direction perpendicular to the contact surface (e.g., in the axial direction). This is a simple way to orient fibers in a desired manner. The fiber orientation can differ between the different layers, for example, 0° and 90°, or 0° and ±45°. Therefore, anisotropy with respect to strength and stiffness can be obtained parallel to the contact surface.

[0044] In embodiments of the invention, the first (polymer) material comprises at least 55% fiber content. This is a considerably high fiber content and allows the control panel to have high strength.

[0045] In embodiments of the invention, the fibers of the first (polymer) material are made of carbon and / or ceramic fillers, particularly ceramic nanofillers. Such fillers also increase the hardness of the plastic. These fibers or fillers are particularly useful in conjunction with the application of hydraulic presses.

[0046] In embodiments of the invention, the first (polymer) material of the body is softer than steel. This is true for most plastic materials.

[0047] This objective is achieved by a hydraulic press (e.g., an axial piston press or a pressure exchanger) that includes a control panel according to any of the disclosed embodiments. Because the control panel experiences less cavitation-related wear, such a hydraulic press requires less maintenance.

[0048] This objective is achieved by a method for manufacturing a control panel for a hydraulic press as described above. The method includes the following steps: A) Provides a body having an arrangement of channel openings and contact surfaces made of a first material (e.g., a first polymer material); B) Deposit a second material (e.g., a second polymer material) in at least one differentiating segment of the body, wherein the second (polymer) material is different from the first (polymer) material.

[0049] The embodiments, modifications, and advantages described regarding the control panel can be applied accordingly to the method, and vice versa.

[0050] In step A), a body is provided. This body can be formed using a non-additive manufacturing method. The body is formed of a first material (e.g., a first polymer material) over its entire thickness. Furthermore, in step B), the body is assembled with a second (polymer) material.

[0051] According to one aspect, the deposition of a second (polymer) material can be accomplished by means of additive manufacturing.

[0052] Additive manufacturing is a general term for manufacturing methods that selectively deposit materials. New materials are added and bonded to existing materials. This can be done by melting two materials, through photochemical reactions, and / or using adhesives. To produce 3D components using additive manufacturing, several layers of (polymer) material are deposited on top of each other. The thickness of each layer needs to be customized depending on the material being processed. The first layer of the second (polymer) material should form a good bond with the first material of the host. Each additional layer of the second material bonds to the previously laid layers. The desired thickness of the second (polymer) material can be achieved by adding additional layers. As a result, additive manufacturing allows for flexible design of the second (polymer) material.

[0053] Metals, polymers, and ceramics can be processed using additive manufacturing. In this application, polymers are used as the second (polymer) material. The polymer can be filled with so-called fillers. Such fillers are, for example, chopped carbon fibers and / or ceramic particles, depending on the desired properties of the polymer.

[0054] By using this method, a second (polymer) material can be deposited in specific sections of the host, thereby creating a surface that is better resistant to cavitation than the first (polymer) material.

[0055] In one embodiment, the second (polymer) material is prefabricated and bonded and / or mechanically fastened to the first (polymer) material at the desired location.

[0056] According to one aspect, the contact surface may be provided with a second (polymer) material layer, such that the entire body is covered with the second (polymer) material at the contact surface. In one embodiment, the entire body may be provided with a second (polymer) material layer, such that the entire body of the first (polymer) material is covered by the second (polymer) material. The second (polymer) material layer may have a varying thickness, such that areas expected to experience high-velocity impact are fitted with a thicker second (polymer) material layer than other areas.

[0057] In an embodiment of the invention, after step A) and before step B), in step A1), a portion of the body is removed to create a recessed segment, wherein in step B), a second (polymer) material is deposited into the recessed segment. For example, the recessed segment is rectangular, annular, or circular in shape. The recessed segment has a depth, for example, greater than 0.1 mm and less than 3 mm, preferably less than 2 mm, or alternatively, the recessed segment penetrates the body in the thickness direction to provide a through-hole. To remove a portion of the body, the body is machined, for example, by milling, drilling, etc.

[0058] Alternatively, recessed sections can be pre-arranged on the provided body. In this case, the recessed sections can be machined to provide surface properties that allow for good bonding between the first (polymer) material and the second (polymer) material.

[0059] According to one aspect, the method includes a step of roughening the surface at the location where the second (polymer) material should be added. The roughening can be formed, for example, by sandblasting and / or similar methods.

[0060] In embodiments of the invention, a microstructured surface is created during step B). The microstructured surface relates to surface properties, particularly its morphology and, for example, roughness. Furthermore, the microstructured surface relates to a top layer. This top layer can extend downwards from the outer surface of the second (polymer) material up to 0.5 mm, but can be 0.1 mm or even 0.05 mm. In this region, fillers such as chopped fibers can be arranged according to a predetermined pattern, such as parallel, annular, circular, spiral, diamond-shaped, rhomboid, arc-shaped, etc. For example, fibers arranged within the microstructured surface are aligned along the direction of movement between the control plate and the cylinder. During the deposition of the second material, the fiber orientation of the microstructured surface is formed. The fibers are laid out and oriented according to the movement of the nozzle of the additive manufacturing machine. The filler affects the surface and its properties. This allows for a trade-off between good frictional properties and good anti-cavitation properties.

[0061] In an embodiment of the invention, in step A1), the worn section of the second material is removed. This allows for the refurbishment of the worn control panel, which is cost-effective and requires minimal work. Only step A1) and subsequent steps need to be repeated to provide a refurbished control panel.

[0062] In embodiments of the invention, following step B), in step C), the deposited second (polymer) material is machined. For example, the second (polymer) material is machined to provide a continuous surface between the second (polymer) material and its adjacent surfaces, thereby creating a flat surface. Furthermore, a microstructured surface in terms of roughness can also be created during this step. Attached Figure Description

[0063] Embodiments of the invention will now be described with reference to the accompanying drawings, in which:

[0064] Figure 1 A schematic cross-sectional view of a water hydraulic press in the form of an axial piston machine is shown;

[0065] Figure 2 Showing a front view of the control panel;

[0066] Figure 3 Show Figure 2 The cross section AA;

[0067] Figure 4 Show Figure 2 The cross section BB;

[0068] Figure 5 A perspective view of the control panel is shown;

[0069] Figure 6 A schematic cross-sectional view of a water-hydraulic press in the form of a pressure exchanger is shown;

[0070] Figure 7 Details of the control panel and its surface are shown.

[0071] Figures 8A to 8E A cross-sectional view is shown during the manufacturing process of the control board of the first embodiment;

[0072] Figures 9A to 9E Cross-sectional views of the control panel at different stages of manufacturing of the second embodiment are shown;

[0073] Figures 10A to 10D The microstructure surface of the second polymer material disposed in a section of the control panel is shown;

[0074] Figures 11A to 11D A cross-sectional view is shown during another approach for manufacturing the control panel; and

[0075] Figure 12 A cross-sectional view of a variant of the control panel is shown, in which the recessed section accommodating the second polymer material has an undercut. Detailed Implementation

[0076] Figure 1 A hydraulic press 1 with a housing 2 is shown, and a cylinder 3 is mounted in the housing 2 in a rotatable manner.

[0077] At least one cylinder 4 is arranged in a cylinder barrel 3. The cylinder 4 is provided with a sleeve 5. The sleeve 5 may be formed of a plastic material, for example, a plastic material in the form of a polymer with ceramic filler. A piston 6 is movable within the cylinder 4 in the direction of the double arrow 7. Control of the movement of the piston 6 within the cylinder 4 is performed by a slipper 8, which is held against a swash plate 10 by a hold-down plate 9.

[0078] The clamping plate 9 is supported on the cylinder 3 via a ball joint having a ball 11. For example, the ball 11 may be made of duplex steel or super duplex steel. The clamping plate 9 has an insert 12 made of the aforementioned polymer material, with ceramic filler in the area in contact with the ball 11. Other embodiments (not shown) have a retaining ball fixed to a retaining plate, and the bearing is located in a separate component.

[0079] The slipper 8 is fitted with a molding part 13, which is made of a polymer with ceramic filler. The molding part 13 extends to include a ball 14 at the front end of the piston 6, wherein the ball 14 forms part of a ball joint.

[0080] The cylinder 3 is mounted in the housing 2 on a bearing surface 15 made of a polymer with ceramic filler, i.e., the bearing surface 15 forms a radial bearing.

[0081] At the end opposite to the swashplate 10, a pressure plate 16 is provided, into which a sleeve 17 is inserted, creating a connection between the pressure plate 16 and the cylinder 4. The pressure plate 16 is supported against a control plate 18, which is fixedly arranged in the housing 2. The control plate 18 is held tightly here by a pair of pins 19. The pressure plate rotates relative to the control plate 18 in conjunction with the cylinder 3, allowing the control plate 18 to control the supply and discharge of hydraulic fluid to and from the cylinder 4 in the correct position.

[0082] The pressure plate 16 is pushed against the control plate 18 by the force of the elastic element (spring) 20 and by the excessive hydraulic pressure generated by the pressure distribution on the pressure plate.

[0083] Figure 2 The control panel 18 shown (also referred to as a "port panel") includes a body 21, an arrangement of channel openings 22 and 23, and a contact surface 24. The contact surface 24 is arranged on the side facing the pressure plate 16. The channel openings 22 and 23 are kidney-shaped.

[0084] The channel openings 22 and 23 are configured for the passage of hydraulic fluid during operation, especially for the intermittent passage (flow) of hydraulic fluid caused by the opening and closing of the channel openings by the mating parts (e.g., the pressure plate 16 of the hydraulic press).

[0085] In other embodiments, the contact surface 24 can be directly supported against the roller 3. Then, no pressure plate 16 is added between the contact surface 24 and the roller 3.

[0086] The main body 21 is made of a flat plastic material, particularly a first polymer material. This first polymer material exhibits friction-reducing properties, meaning that even when water is used as the hydraulic fluid, the friction between the control plate 18 and the pressure plate 16 remains low. Suitable plastic materials include, for example, PEEK.

[0087] The first polymer material is a fiber-reinforced plastic material having fibers with a length of at least 5 mm.

[0088] At least in the thickness region adjacent to the contact surface 24, more than 50% of the fibers include angles less than 30% or 30 degrees with respect to the contact surface 24. This can be achieved in a simple manner by constructing the body 21 from multiple prepregs stacked on top of each other. Prepreg is a prefabricated material with a large number of fibers arranged in parallel and impregnated with an uncured polymer material. When these prepregs are stacked on top of each other, multiple fiber layers are created, in which the fibers in the layers are more or less parallel to each other and parallel to the contact surface 24. The fibers in the layers can be oriented in different directions; however, they are substantially parallel to the contact surface 24. Therefore, the body 21 can be provided with suitable strength and stiffness in all directions parallel to the contact surface 24. In the direction perpendicular to the contact surface 24, the body can be slightly compressed to form an elastic element, thereby suppressing noise.

[0089] When using prepreg to produce body 21, the polymer material may include at least 55% fiber content. The fibers are made of carbon, glass, or another filler material (such as ceramic filler).

[0090] Using prepregs has the following advantages: fiber orientation places as many fibers as possible parallel to the contact surface 24, so that tribological contact can be formed on the sides of the fibers rather than at the ends.

[0091] Greater flexibility is available in manufacturing. The use of a fiber-reinforced first polymer material (especially a combination of high fiber content, long fiber length, and favorable fiber orientation) eliminates the need to use injection molding to overlay a molded steel insert to form the body 21. Therefore, the final form of the body 21 is independent of the geometry of the injection molding tool or the steel insert. Furthermore, since the body 21 no longer contains an overlay molded steel insert, it is not necessary to ensure a uniform thickness of the plastic material layer in the kidney-shaped channel openings 22, 23.

[0092] Using prepregs has the further advantage of avoiding the inclusion of air. This results in less performance dispersion in control panels made from this composite material.

[0093] The steel ring 25 can be additionally disposed around the main body 21. Figure 1 (Not shown in the image). The steel ring ensures dimensional stability in the radial direction, meaning that when force or pressure is applied to the control plate 18, the body can be slightly compressed; however, the body will not expand in the radial direction.

[0094] The contact surface 24 includes a sliding track 26, and the contact surface 24 within the sliding track 26 may be smoother than the exterior of the sliding track 26. The pressure plate 26 contacts the control plate 18 only in the area of ​​the sliding track 26.

[0095] Figure 5 The control panel 18 is shown from the side opposite to the contact surface 24. Holes 27 for accommodating locating pins 19 can be seen.

[0096] Figure 6 A hydraulic press in the form of a pressure exchanger 101 is schematically shown, wherein the control panel 18 as described above can be used for the same purpose.

[0097] The pressure exchanger 101 includes a housing 102, a drive shaft 103, and a cylinder 104 rotatably arranged within the housing 102. The cylinder 104 includes a plurality of cylinders 105 evenly distributed around the drive shaft 103 in a circular (circumferential) direction.

[0098] The cylinder 104 is rotatably fixed to the drive shaft 103. The drive shaft 103 includes a driven end 106. The driven end 106 may be provided with a coupling to connect a drive motor or other drive device to rotate the drive shaft 103.

[0099] Control plates 107 and 108 are arranged at each end of cylinder 104. Cylinder 104 rotates relative to control plates 107 and 108. Control plates 107 and 108 may have... Figures 2 to 5 The structure of the control panel 18 in the illustrated embodiment.

[0100] The first control panel 107 includes two kidney-shaped channel openings 109 and 110, which are connected to ports 111 and 112 in the end portion 113 of the housing 102. The second control panel 108 includes two kidney-shaped channel openings 14 and 15, which are connected to port 116 (the other port is not shown) in the second end portion 117 of the housing 102.

[0101] A thrust plate 118 is disposed between the cylinder 104 and the second control plate 108. The thrust plate 118 is sealed relative to the cylinder 105 of the cylinder 104 and is movable slightly relative to the cylinder 104, so that the thrust plate 118 can remain in contact with the second control plate 108 during operation.

[0102] Even under these conditions, control panels 107 and 108 can be manufactured without steel or other metal inserts. Control panels 107 and 108 are made of a flat polymer material.

[0103] Figure 7 The control panel 18 is shown in a 3D view. (Usage and...) Figures 1 to 5 The same reference numerals are used in the accompanying drawings.

[0104] Figure 7 An enlarged view of the surface of the control plate 18 in the region of the sliding track 26 is shown. Fibers 28 and 29 are schematically shown arranged substantially parallel to the surface of the control plate 18. Fiber 28 is arranged at an angle of approximately 90° relative to fiber 29. This can be achieved by using a first prepreg comprising fiber 28 and stacking another prepreg on top of the first prepreg, wherein the other prepreg comprises fiber 29 and is arranged relative to the first prepreg at the aforementioned angle.

[0105] Figures 8A to 8E The different stages of manufacturing control board 18 according to the first embodiment are shown in partial cross-sectional view AA.

[0106] Figure 8A The first step A is depicted, providing a main body 21 of a control panel equipped with a circular sliding track 26. The main body 21 is machined to include a recessed section 30, such as... Figure 8B As depicted. For example, milling out a recessed section 30.

[0107] A second polymer material 31 is deposited in the recessed section. The deposition of the second polymer material 31 may, for example, include additive manufacturing.

[0108] During the additive manufacturing process, polymer material is deposited along a predetermined path in the layer through a nozzle (not depicted). By depositing polymer material on top of the previous layer, a solid polymer portion can be formed. This process is repeated until the thickness of the second polymer is sufficiently strong. In this invention, the second polymer material is deposited within the recessed section 30.

[0109] The recessed section 30 is recessed relative to the adjacent surface by more than 0.1 mm but less than 3 mm, preferably less than 2 mm. The recessed section 30 is fitted with a second polymer material 31 to provide a cavitation-resistant section on the body, such as... Figure 8C Provided.

[0110] Depending on further production, a second polymer material 31 is applied by means of additive manufacturing to form a flat surface relative to the adjacent surface of the recessed segment 30. In this case, the additive manufacturing method can provide a microstructured surface, such as that later bonded. Figures 10A to 10C As described.

[0111] Alternatively, a second polymer material 31 is deposited to "overfill" the recessed section 30, causing the polymer material 31 to protrude relative to the adjacent surface of the circular sliding track 26. In this case, the protruding portion of the second polymer material 31 is machined to create a flat surface in conjunction with the circular sliding track 26, such as... Figure 8D What is depicted.

[0112] In another alternative, the second polymer material 31 is configured as a solid element, which is fixed to the recessed section 30 by means of gluing, thermal bonding, or the like. In this alternative, the second polymer material 31 may extend beyond the circular sliding track 26, allowing the second polymer material 31 to be machined to match the surface of the sliding track 26, thereby forming a flat surface.

[0113] Figure 8E The control panel 18 is shown to have a second polymer material 31 assembled within a recessed section 30. The second polymer material 31 is worn as shown due to its irregular surface. The worn second polymer material 31 can be as described above regarding... Figure 8B The described material is removed. To this end, the recessed section 30 is machined back to its original shape, thereby removing the deposited second material 31. Then, according to... Figure 8A and 8B The next step is to assemble the recessed section 30 with a new second polymer material 31.

[0114] Figures 9A to 9E Corresponding to Figures 8A to 8E The recessed section 31 penetrates the body 21 in the thickness direction. The body 21 is provided as being formed of a first polymer material, such as... Figure 9AAs shown. Subsequently, a through hole (recessed section 30) is provided in the main body 21, as shown. Figure 9B As shown. The recessed section 30 is fitted with the second polymer material 31 by means of additive manufacturing or by means of fixing an element formed of the second polymer material 31 into the recessed section 30.

[0115] When an element formed of the second polymer material 31 is fixed into a recessed section, the element is formed according to the shape of the recessed section 30. The element is then bonded to the body 21 formed of the first polymer material by means of adhesive bonding or thermal bonding. To achieve a flat surface, the element formed of the second polymer material 31 is made too large, causing the second polymer material 31 to extend beyond the recessed section 30. The excess second polymer material 31 is removed by means of machining (e.g., milling).

[0116] When the recessed section 30 is assembled using additive manufacturing, a second polymer material 31 is deposited into the recessed section 30 through a nozzle, thereby bonding the second polymer material 31 to the body 21. A layer of second polymer material 31 is provided on top of a previously deposited layer of second polymer material 31 to fill the recessed section 30.

[0117] A second polymer material 31 may be deposited beyond the recessed section 30. In this case, the extended portion of the second polymer material 31 is machined to match the adjacent surface of the sliding track 26.

[0118] Alternatively, a second polymer material 31 is deposited using additive manufacturing to match the surface of the sliding track 26. In this case, additive manufacturing can provide a microstructured surface to the second polymer material 31, such as a bonding... Figures 10A to 10C As described.

[0119] As a result, the second polymer material 31 is flat relative to the adjacent surface (e.g., the sliding track 26).

[0120] Figure 9E The control panel 18 is depicted including a section of a second polymer material 31 disposed in a recessed section 30. The second polymer material 31 is worn, as indicated by its rough surface. This can be determined according to... Figure 9B Remove the worn second polymer material 31, and according to Figure 9C and Figure 9D The process involves refurbishing with a new second polymer material 31. As a result, the control panel 18 with the second polymer material 31 in the worn sections can be refurbished.

[0121] Figures 10A to 10DAn excerpt of the microstructure surface of the second polymer material 31 is shown. The second polymer material 31 is disposed in the recessed section 30 by means of additive manufacturing. The second polymer material 31 is extruded through a nozzle, such that the fibers 32 disposed within the second polymer material 31 are accordingly oriented. By depositing the second polymer material 31 onto the substrate 21 or onto a previously deposited layer, the fibers 32 are deposited along this orientation. As the nozzle moves and the second polymer material 31 is deposited, the fibers themselves are oriented in the path of the nozzle, such that the fiber 32, in particular the fiber orientation, can be adjusted by accordingly defining the path of the nozzle.

[0122] Figure 10A and Figure 10B A microstructured surface is shown, in which fibers 32 are oriented parallel to each other. Figure 10A In this process, for example, the nozzle moves from left to right to deposit the second polymer material 31 and its fibers 32 accordingly.

[0123] Similar to Figure 10A , Figure 10B The orientation of parallel fibers 32 is shown, where the fibers are oriented vertically. Therefore, the nozzle moves from top to bottom to deposit the second polymer material 31.

[0124] Figure 10C The second polymer material 31 is depicted being deposited such that the fibers follow the curvature of the sliding track 26 and are oriented in an arc.

[0125] exist Figure 10D In this configuration, the fibers are oriented in a circular pattern. Other fiber forms and orientations include spiral, diamond, and rhomboid patterns. When choosing a shape, existing conditions should be taken into account.

[0126] The orientation of fiber 32 affects the surface properties of the second polymer material 31, especially its anticavitation properties.

[0127] Figures 11A to 11D Another approach for manufacturing the control panel 18 according to the present invention is shown. Figures 11A to 11D This again demonstrates the process of manufacturing control panel 18 with... Figure 2 The cross-sectional view at the location corresponding to AA in the diagram.

[0128] exist Figure 11A The initial body 21 for the control panel 18 is provided. The initial body 21 is formed entirely of a first material, such as a first polymer material. The basic shape of the initial body 21 is annular, like a disc with a central opening 21a. The central opening 21a is not a channel opening 22, 23.

[0129] and Figure 8A Unlike the initial body 21, which does not include a circular sliding track (Figure 8A (Ref. 26A in the attached figure). In this example, the sliding track may be located on a mating part that slides against the control panel 18.

[0130] In a further step, the main body 21 is machined to form the recessed section 30 (see...). Figure 11B Similar to the description above. Note that additional steps may be performed to roughen the surface of the body 21 in the recessed section 30, such as by sandblasting.

[0131] Then, leading to such Figure 11C In a further step of the state shown, a second material is added. In this example, the second material is added only at the recessed section 30. The second material may be a second polymer material 31 according to one of the modifications described above.

[0132] A second (polymer) material 31 can be added by means of additive manufacturing.

[0133] Alternatively, a second (polymer) material 31 may be provided as one or more prefabricated parts. In this case, the prefabricated second (polymer) material 31 is fixed to the body 21, for example, by gluing.

[0134] According to one approach, a second (polymer) material 31 (or a suitable precursor) is added as powder and / or granules to the recess. By heating and melting, the second (polymer) material 31 can be permanently fixed to the body 21.

[0135] like Figure 11C As shown, the second (polymer) material 31 may protrude too much from the recessed section 30. In this case, further machining steps can be performed to tear off at least a portion of the protruding portion of the second (polymer) material 31. Figure 11D In the middle, a portion of the second (polymer) material 31 forming a part of the surface at the contact surface 24 of the control plate 18 is flush with the adjacent portion of the surface at the contact surface 24 formed by the body 21.

[0136] Naturally, control panel 18 can be refurbished after exposure to cavitation erosion and / or other types of wear. For example, it can be repeatedly... Figures 11B to 11D The steps shown. In this case, leading to... Figure 11B In the steps shown, the "old" second (polymer) material is removed.

[0137] Optionally, the recessed section 30 can be machined to have one or more undercut portions 30a. Figure 12The diagram shows a variation of the control plate 18, in which a recessed section 30 has an undercut 30a. The undercut 30a locks the second polymer material 31 to the body 21. For example, in addition to the bond that should be formed by fusing the materials together, the added second polymer material 31 may also be melted into one or more undercuts 30a to form a mechanical locking mechanism.

Claims

1. A control plate (18) configured to fit for a hydraulic machine for hydraulic fluid, wherein, The control plate (18) comprises a main body (21) having an arrangement of passage openings (22, 23) for passing the hydraulic fluid and a contact face, wherein the entire thickness of the main body (21) is formed by a main material, wherein the main material is a first polymer material, characterized in that the main body (21) comprises at least one differential section made of a second polymer material (31), wherein the second polymer material (31) is different from the main material.

2. The control panel (18) according to claim 1, characterized in that The at least one differential section extends at least partially at a surface of the control plate (18).

3. The control panel (18) according to claim 1 or 2, characterized in that The first polymer material is a fiber-reinforced polymer.

4. Control panel (18) according to any one of the preceding claims, characterized in that The control plate (18) comprises a circular sliding track (26) extending in a circular direction at the contact face, wherein at least one of the passage openings (22, 23) is arranged in the sliding track (26), and wherein the second polymer material (31) is arranged within the circular track (26).

5. The control panel (18) according to claim 4, characterized in that The circular sliding track (26) is convex with respect to a surface adjacent to the circular sliding track (26).

6. Control panel (18) according to any one of the preceding claims, characterized in that The second polymer material (31) is arranged at least between adjacent passage openings (22, 23) in a circumferential direction.

7. Control panel (18) according to any one of the preceding claims, characterized in that The second material is at least partially arranged in a recess section (30) of the main body (21).

8. The control panel (18) according to claim 7, characterized in that The recess section (30) has at least one undercut (30a) such that the second polymer material (31) is mechanically locked to the main body (21).

9. Control panel (18) according to any one of the preceding claims, characterized in that The differential section has a thickness of more than 0.1 mm and less than 3 mm, preferably less than 2 mm, or the differential section extends through the thickness of the control plate (18).

10. Control panel (18) according to any one of the preceding claims, characterized in that The second polymer material (31) comprises a microstructured surface.

11. Control panel (18) according to any one of the preceding claims, characterized in that The second polymer material (31) is PEEK or PEEK comprising one or more filler materials.

12. Hydraulic machine comprising a control plate (18) according to any of the preceding claims.

13. A method of manufacturing a control panel (18) for a hydraulic press, wherein, The control plate (18) comprises a main body (21) having an arrangement of kidney-shaped openings (22, 23) and a contact face, wherein the entire thickness of the main body (21) is formed by a first polymer material, wherein the method comprises the following steps: A) providing the main body (21) made of a first polymer material having an arrangement of passage openings (22, 23) and a contact face; B) depositing a second polymer material (31) within a section of the main body (21), wherein the second material is different from the first material.

14. The method of claim 13, wherein, After step A) and before step B), in step A1) a portion of the main body (21) is removed to create a recess section (30), wherein in step B) the second polymer material (31) is deposited into the recess section (30).

15. The method of claim 14, wherein, In step A1) a wear section of the second polymer material (31) is removed.

16. The method according to any one of claims 13 to 15, characterized in that, A microstructured surface is created during step B). A) providing the main body (21) made of a first polymer material having an arrangement of passage openings (22, 23) and a contact face; B) depositing a second polymer material (31) within a section of the main body (21), wherein the second material is different from the first material. After step A) and before step B), in step A1) a portion of the main body (21) is removed to create a recess section (30), wherein in step B) the second polymer material (31) is deposited into the recess section (30). In step A1) a wear section of the second polymer material (31) is removed. A microstructured surface is created during step B).

Images