Hydraulic direct-drive valve forming method and hydraulic direct-drive valve

Abstract

The invention discloses a hydraulic direct-drive valve forming method and a hydraulic direct-drive valve, and relates to the technical field of hydraulic direct-drive valves.The hydraulic direct-drive valve forming method comprises the steps that a three-dimensional model of the hydraulic direct-drive valve is constructed, and a runner cavity and a valve body structure of the three-dimensional model are subjected to regional splitting; structural information of the runner cavity is obtained, layer-by-layer forming is conducted based on the structural information of the runner cavity, and a runner green body is obtained; obtaining structure information of the valve body structure, and constructing a three-dimensional model of a wrapping shell wrapping the valve body structure on the outside based on the structure information of the valve body structure; forming the cladding shell layer by layer, bonding and fixing the cladding shell and the runner green body to obtain a direct-drive valve casting model, and performing first post-treatment on the direct-drive valve casting model; casting based on the direct-drive valve casting model to obtain a direct-drive valve blank; and the direct-drive valve blank is subjected to model removal treatment and / or secondary post-treatment, and a finished direct-drive valve product is obtained. Under the condition of a valve body with the same size, the weight is lighter, and the flow is larger than that of other valves.

Description

Technical Field

[0001] The present invention relates to the technical field of hydraulic direct-drive valves, and in particular to a hydraulic direct-drive valve forming method and a hydraulic direct-drive valve. Background Art

[0002] The electro-hydraulic servo valve is a key hydraulic control component that can accurately achieve the output force and direction of the hydraulic oil by adjusting the input signal. It is widely used in industrial automation, machinery manufacturing, weapons and equipment, aerospace and other fields. As a common type of hydraulic servo valve, the direct-drive servo valve (abbreviated as "direct-drive valve") is much larger in size and weight than the two-stage valve or multi-stage valve of the same flow level. When the flow level reaches 100 L / min or above, the direct-drive valve will exceed 10 kg, and the flow channel cross-sectional area of ​​the direct-drive valve manufactured using traditional methods will be very large.

[0003] Due to the lightweight generative flow channel design of large flow direct-drive valves above 100 L / min, the maximum flow channel diameter in the structure is greater than 12 mm, the number of branch layers is more, the flow channel structure is more complex, and there are a large number of small-angle and large-area slopes inside the flow channel. The processing difficulty is relatively high, and it is even more difficult to break through the technology of expanding the internal flow channel to obtain a larger flow while keeping the original direct-drive valve volume unchanged. Therefore, it is crucial to form a small-volume and high-flow direct-drive valve. Summary of the invention

[0004] The main purpose of the present invention is to provide a hydraulic direct-drive valve forming method and a hydraulic direct-drive valve, aiming to increase the flow rate of the direct-drive valve while maintaining the original direct-drive valve volume unchanged.

[0005] To achieve the above object, the hydraulic direct-drive valve forming method proposed in the present invention comprises the following steps: Acquire information of the hydraulic direct-drive valve and construct a three-dimensional model, and perform regional segmentation of a flow channel cavity and a valve body structure forming the flow channel cavity of the three-dimensional model; Acquiring structural information of the split flow channel cavity, and performing layer-by-layer forming based on the structural information of the flow channel cavity to obtain a flow channel green body; Acquiring structural information of the valve body structure, and constructing a three-dimensional model of a covering shell covering the valve body structure externally based on the structural information of the valve body structure; Forming the coating shell layer by layer, bonding and fixing the coating shell and the flow channel green body to obtain a direct-drive valve casting model, and performing a first post-processing on the direct-drive valve casting model; Casting is performed based on the direct-drive valve casting model to obtain a direct-drive valve blank; The direct-drive valve blank is subjected to a demolding process and / or a second post-processing to obtain a direct-drive valve finished product.

[0006] In one embodiment, the first post-processing includes the steps of solidification and degreasing of the direct-drive valve casting model; the model removal treatment includes the subtractive treatment of the flow channel green body and / or the coating shell; the second post-processing includes the flow channel cleaning and / or overall sintering steps of the direct-drive valve blank.

[0007] In one embodiment, the cross-sectional shape of the flow channel cavity may be any one of a circle, an ellipse, a teardrop, a regular polygon or an oblique polygon.

[0008] In one embodiment, the flow channel cavity includes a main channel and a branch channel extending from the main channel, and the angle between the branch channel and the axial extension direction of the main channel is 10°-170°.

[0009] In one embodiment, the maximum cross-sectional distance of the main channel is 12 mm-100 mm; the minimum cross-sectional distance of the branch channel at the end is 1 mm~30 mm, and the cross-sectional distance of the branch channel in the same direct drive valve decreases as the number of branches increases.

[0010] In one embodiment, the branch channel in the direct-drive valve branches 2-10 times, and the connections between two adjacent branches are smoothly connected.

[0011] The present invention also provides a hydraulic direct-drive valve forming method, comprising the following steps: Acquire information of the hydraulic direct-drive valve and construct a three-dimensional model, and perform regional segmentation of a flow channel cavity and a valve body structure forming the flow channel cavity of the three-dimensional model; Acquire structural information of the split flow channel cavity, and use foundry sand to perform layer-by-layer forming based on the structural information of the flow channel cavity to obtain a flow channel green body; Acquiring structural information of the valve body structure, and constructing a three-dimensional model of a covering shell covering the valve body structure externally based on the structural information of the valve body structure; Divide the three-dimensional model of the covering shell into different areas, and obtain the position information and structure information of each area; The coating shell is formed layer by layer using foundry sand in different regions, the coating shell and the flow channel green body of all regions are bonded and fixed to obtain a direct-drive valve casting model, and the direct-drive valve casting model is subjected to a first post-processing; Based on the direct-drive valve casting model, the material to be formed is used for casting to obtain a direct-drive valve blank; The direct-drive valve blank is subjected to model removal and a second post-processing to obtain a direct-drive valve finished product.

[0012] The present invention also provides a hydraulic direct-drive valve forming method, comprising the following steps: Acquire information of the hydraulic direct-drive valve and construct a three-dimensional model, and perform regional segmentation of a flow channel cavity and a valve body structure forming the flow channel cavity of the three-dimensional model; Acquiring structural information of the split runner cavity, and using a resin material or a wax material to perform layer-by-layer forming based on the structural information of the runner cavity to obtain a runner green body; The outer periphery of the flow channel green body is coated with ceramic material, and then a corresponding valve body structure is formed with resin material or wax material; Constructing a three-dimensional model of a coating shell covering the valve body structure outside the valve body structure, and forming the coating shell using a ceramic material to obtain a direct-drive valve casting model, and performing a first post-processing on the direct-drive valve casting model; Based on the direct-drive valve casting model, the material to be formed is used for casting to obtain a direct-drive valve blank; The direct-drive valve blank is subjected to model removal and a second post-processing to obtain a direct-drive valve finished product.

[0013] The present invention also provides a hydraulic direct-drive valve forming method, comprising the following steps: Acquire information of the hydraulic direct-drive valve and construct a three-dimensional model, and perform regional segmentation of a flow channel cavity and a valve body structure forming the flow channel cavity of the three-dimensional model; Acquire structural information of the split flow channel cavity, and use foundry sand to perform layer-by-layer forming based on the structural information of the flow channel cavity to obtain a flow channel green body; Acquiring structural information of the valve body structure, and constructing a three-dimensional model of a covering shell covering the valve body structure externally based on the structural information of the valve body structure; Using a resin material or a wax material to form a valve body structure, and using a ceramic material to form the covering shell outside the valve body structure to obtain a direct-drive valve casting model, and performing a first post-processing on the direct-drive valve casting model; Based on the direct-drive valve casting model, the material to be formed is used for casting to obtain a direct-drive valve blank; The direct-drive valve blank is subjected to model removal and a second post-processing to obtain a direct-drive valve finished product.

[0014] The present invention also proposes a hydraulic direct-drive valve, which is formed by a hydraulic direct-drive valve forming method as described above. The hydraulic direct-drive valve is provided with a combining interface for use with other valves, and is used to combine with other valves to expand the flow level.

[0015] The technical solution of the present invention is to decompose the three-dimensional model of the direct-drive valve, separately form the flow channel to obtain the flow channel green body, form a coating shell covering the valve body structure based on the structural information of the valve body structure, and bond the flow channel green body inside the coating shell to obtain a direct-drive valve casting model, and cast the direct-drive valve blank based on the direct-drive valve casting model. The blank can avoid the collapse of the flow channel or the difficulty in forming when forming a larger-sized flow channel, so that when forming a small-volume direct-drive valve, the internal flow channel size is significantly increased, laying the foundation for increasing the flow rate of the liquid in the direct-drive valve finished product; in addition, on this basis, through the first post-processing, model removal and second post-processing, the direct-drive valve blank is solidified, degreased, the flow channel is removed, the coating shell is removed, and the flow channel is cleaned, sintered and other processes are performed, and finally the direct-drive valve finished product is obtained, which achieves that the flow rate is larger than that of other valves under the same volume of valve body, and the structural performance is intact and the forming process is simple. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0017] Figure 1 The steps of an embodiment of the hydraulic direct drive valve forming method provided by the present invention are as follows Figure 1 ; Figure 2 A schematic structural diagram of a flow channel cavity in an embodiment of a hydraulic direct-drive valve forming method provided by the present invention; Figure 3 A schematic structural diagram of a valve body structure of an embodiment of a hydraulic direct-drive valve forming method provided by the present invention; Figure 4 The steps of another embodiment of the hydraulic direct drive valve forming method provided by the present invention are as follows Figure 2 ; Figure 5 The steps of another embodiment of the hydraulic direct drive valve forming method provided by the present invention are as follows: Figure 3 ; Figure 6 The steps of another embodiment of the hydraulic direct drive valve forming method provided by the present invention are as follows: Figure 4 ; Figure 7 A schematic structural diagram of an embodiment of a hydraulic direct-drive valve provided by the present invention.

[0018] Description of Figure Numbers: 1. Hydraulic direct drive valve; 11. Flow channel cavity; 12. Valve body structure.

[0019] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0020] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0021] It should be noted that if there are directional indications (such as up, down, left, right, front, back, etc.) involved in the embodiments of the present invention, the directional indication is only used to explain the relative position relationship, movement status, etc. between the components in a certain specific posture. If the specific posture changes, the directional indication will also change accordingly. Unless otherwise clearly specified and limited, the terms "installation", "connection", and "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, and it can be the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to the specific circumstances.

[0022] In addition, if there are descriptions of "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Thus, the features defined as "first" and "second" can explicitly or implicitly include at least one of the features. Moreover, the terms "include", "comprise", or any other variants thereof are intended to cover non-exclusive inclusion, so that the process, method, article, or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article, or device. In the absence of further restrictions, the elements defined by the sentence "include one..." do not exclude the presence of other identical elements in the process, method, article, or device including the elements. In addition, if "and / or" or "and / or" appears in the full text, its meaning includes three parallel schemes, taking "A and / or B" as an example, including scheme A, or scheme B, or schemes that A and B meet at the same time. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the fact that ordinary technicians in the field can implement it. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0023] The electro-hydraulic servo valve is a key hydraulic control component that can accurately achieve the output force and direction of the hydraulic oil by adjusting the input signal. It is widely used in industrial automation, machinery manufacturing, weapons and equipment, aerospace and other fields. As a common type of hydraulic servo valve, the direct-drive servo valve (abbreviated as "direct-drive valve") is much larger in size and weight than the two-stage valve or multi-stage valve of the same flow level. When the flow level reaches 100 L / min or above, the direct-drive valve will exceed 10 kg, and the flow channel cross-sectional area of ​​the direct-drive valve manufactured using traditional methods will be very large.

[0024] Due to the lightweight generative flow channel design of large flow direct-drive valves above 100 L / min, the maximum flow channel diameter in the structure is greater than 12 mm, the number of branch layers is more, the flow channel structure is more complex, and there are a large number of small-angle and large-area slopes inside the flow channel. The processing difficulty is relatively high, and it is even more difficult to break through the technology of expanding the internal flow channel to obtain a larger flow while keeping the original direct-drive valve volume unchanged. Therefore, it is crucial to form a small-volume and high-flow direct-drive valve.

[0025] See also Figure 1 The present invention proposes a hydraulic direct-drive valve forming method comprising the following steps: S1: Acquire information of the hydraulic direct-drive valve and construct a three-dimensional model, and perform regional segmentation of a flow channel cavity and a valve body structure forming the flow channel cavity of the three-dimensional model; S2: obtaining structural information of the split flow channel cavity, and performing layer-by-layer forming based on the structural information of the flow channel cavity to obtain a flow channel green body; S3: Acquire structural information of the valve body structure, and externally construct a three-dimensional model of a covering shell covering the valve body structure based on the structural information of the valve body structure; S4: forming the coating shell layer by layer, bonding and fixing the coating shell and the flow channel green body, obtaining a direct-drive valve casting model, and performing a first post-processing on the direct-drive valve casting model; S5: Casting is performed based on the direct-drive valve casting model to obtain a direct-drive valve blank; S6: De-molding the direct-drive valve blank and / or performing a second post-processing to obtain a direct-drive valve finished product.

[0026] It should be noted that the flow channel cavity refers to the channel through which the liquid flows in the hydraulic direct-drive valve. The cross-sectional size of the channel will affect the flow rate and flow velocity of the liquid. When the cross-sectional area of ​​the flow channel cavity is larger, the difficulty of forming will increase significantly, unless the volume of the direct-drive valve is expanded. Otherwise, the cross-sectional area of ​​the flow channel cavity will be difficult to increase without changing the volume of the direct-drive valve.

[0027] Specifically, the method preferentially forms the flow passages that are easy to damage or handle, and then forms the valve body. Only the flow passages in the valve body need to be handled, and the valve body can be used as a green body of the direct-drive valve for subsequent processing to obtain a finished product.

[0028] In an embodiment of the present invention, the first post-processing includes the steps of solidification and degreasing of the direct-drive valve casting model; the model removal treatment includes the subtractive treatment of the flow channel green body and / or the coating shell; the second post-processing includes the flow channel cleaning and / or overall sintering steps of the direct-drive valve blank.

[0029] It should be noted that there is no restriction on the method of model removal. Since it is difficult to completely remove the material inside the flow channel model without damaging the valve body structure by conventional means, the materials used to form the flow channel green body are all easy-to-process materials. The brittleness, high temperature resistance, and even unstable performance after forming of this type of material can be used as a breakthrough point. At the same time, the coating shell wrapped around the outside of the valve body structure is easy to handle, but needs to withstand the high temperature of casting, and is easy to peel off from the valve body structure after casting and cooling. Therefore, the high temperature resistance, brittleness, and even unstable performance of this type of material after forming can be used to achieve efficient and precise peeling.

[0030] Specifically, in a specific embodiment of the present invention, the materials of the formed flow channel green body and the formed covering shell are not limited, so as to achieve the above-mentioned effects and facilitate subsequent removal.

[0031] Please combine Figure 2 , Figure 3 and Figure 7 In the embodiment of the present invention, the cross-sectional shape of the flow channel cavity 11 can be any one of a circle, an ellipse, a teardrop, a regular polygon or an oblique polygon.

[0032] It should be noted that when the cross-sectional area of ​​the flow channel cavity 11 is enlarged to a certain size, the collapse or cracking of the flow channel cavity 11 during forming will become more serious, the difficulty of forming the flow channel cavity 11 will increase, and the cross-sectional shape of the flow channel cavity 11 will also be limited; Specifically, the cross-sectional shape of the flow channel cavity 11 will not be circular, and under the influence of the gravity of the material, the side wall of the flow channel cavity 11 will no longer be able to fully support the top material, thus causing the top structure to collapse; In view of this situation, in the prior art, in order to improve the support of the side wall of the flow channel cavity 11 on the top material of the flow channel, the flow channel is designed to be a teardrop shape or a polygon. However, this type of shape will cause adjacent edges to form a small angle, which is prone to cracks during post-processing, thereby causing direct-drive valve products to have quality problems and be eliminated.

[0033] In summary, when the cross-sectional area of ​​the flow channel cavity 11 is expanded to a certain size, the cross-sectional shape of the flow channel cavity 11 will be a direct factor affecting the structural performance of the direct-drive valve product. However, it is inevitable that the adjustment of the shape will not significantly increase the liquid flow rate. Through this method, the flow channel green body is formed first, and the various parts or regions of the valve body are formed and fixed on this basis. This method can avoid the technical defects of the flow channel cavity 11 when the valve body is directly formed, thereby achieving the adaptation of the cross-sectional shape of the flow channel cavity 11 to various shapes and the size expansion of the flow channel cavity 11 without changing the volume of the valve body structure 12.

[0034] In an embodiment of the present invention, the flow channel cavity 11 includes a main channel and a branch channel extending from the main channel, and the angle between the branch channel and the axial extension direction of the main channel is 10°-170°.

[0035] It should be noted that if the angle between the main channel and the branch channel in the flow channel cavity 11 is too small, cracks may appear during the post-processing process listed above. Therefore, in conventional designs, in order to avoid the impact of this type of angle on the product, the angle between the main channel and the branch channel in the flow channel cavity 11 is usually controlled to be above 30°.

[0036] It can be understood that the method provided in the present application will increase the fault tolerance of small-angle structures, have a wider range of applications, and have fewer restrictions on the main channel and branch channels in the flow channel cavity 11.

[0037] In an embodiment of the present invention, the maximum distance of the cross section of the main channel is 12 mm-100 mm; the minimum distance of the cross section of the branch channel at the end is 1 mm-30 mm; Specifically, the maximum distance of the cross section of the main channel can be 12 mm, 12.5 mm, 15 mm, 20 mm, 25 mm, 37 mm, 50 mm, 76 mm, 89 mm, 93 mm, 100 mm; The minimum cross-sectional distance of the branch channel at the end can be 1 mm, 7 mm, 15 mm, 25 mm, or 30 mm.

[0038] Preferably, in a specific embodiment of the present invention, the maximum distance of the cross section of the main channel is 15 mm-80 mm, and the minimum distance of the cross section of the branch channel at the end is 8 mm-20 mm.

[0039] It should be noted that the maximum cross-sectional distance of the main channel and the minimum cross-sectional distance of the branch channel at the end are the flow channel dimensions formed by considering the changes in the direct-drive valve body, and are not the changing dimensions of the main channel and the branch channel in a single direct-drive valve. In this application, the direct-drive valve flow level reaches 100 L / min as an example, and the weight of the direct-drive valve does not exceed 10 kg. At this time, the maximum cross-sectional distance of the main channel is 12 mm-100 mm, and correspondingly, the minimum cross-sectional distance of the branch channel at the end is 1 mm~10 mm.

[0040] Specifically, in the same direct-drive valve, the cross section of the branch channel decreases as the number of branches increases.

[0041] In an embodiment of the present invention, the number of branches of the same branch channel in the direct-drive valve is 2-10, and the connections between two adjacent branches are smoothly connected.

[0042] It should be noted that in order to better reduce the influence of the small-angle slope in the flow channel cavity 11 on the formation of the direct-drive valve, the adjacent branches at both ends are usually smoothly connected so that the two small-angle slopes are connected into multiple large-angle slopes.

[0043] Specifically, there is no limit on the number of branches of different branch channels in the same direct-drive valve, and they can be the same or different. The number of branches of the same branch channel to the end varies with the volume of the direct-drive valve, the size of the internal flow channel, and the density. There is no absolute limit here.

[0044] Preferably, the number of branches of the same branch channel in the direct-drive valve is 2-6, and each time a new branch is formed, the cross-sectional size of the new branch channel will decrease.

[0045] It can be understood that the same liquid flow rate will be different when passing through flow channels with different cross-sections, and the liquid pressure will also increase as the cross-section decreases. This design is to ensure the liquid pressure at the end of the flow channel cavity 11.

[0046] In an embodiment of the present invention, the three-dimensional model of the direct-drive valve is split, the flow channel is formed separately to obtain a flow channel blank, a coating shell covering the valve body structure is formed based on the structural information of the valve body structure, and the flow channel blank is bonded therein to obtain a direct-drive valve casting model, and a direct-drive valve blank is cast based on the direct-drive valve casting model. The blank can avoid the collapse of the flow channel or the difficulty in forming when forming a larger-sized flow channel, so that when a small-volume direct-drive valve is formed, the internal flow channel size is significantly increased, laying the foundation for increasing the flow rate of the liquid in the direct-drive valve finished product; in addition, on this basis, through the first post-processing, model removal and second post-processing, the direct-drive valve blank is solidified, degreased, the flow channel is removed, the coating shell is removed, and the flow channel is cleaned, sintered and other processes are performed, and finally the direct-drive valve finished product is obtained, which achieves a larger flow rate than other valves in the case of the same volume of valve body, and at the same time, the structural performance is intact and the forming process is simple.

[0047] See also Figure 4 The present invention also proposes a hydraulic direct-drive valve forming method, comprising the following steps: S1: Acquire information of the hydraulic direct-drive valve and construct a three-dimensional model, and perform regional segmentation of a flow channel cavity and a valve body structure forming the flow channel cavity of the three-dimensional model; S2: obtaining structural information of the split flow channel cavity, and using foundry sand to perform layer-by-layer forming based on the structural information of the flow channel cavity to obtain a flow channel green body; S3: acquiring structural information of the valve body structure, and constructing a three-dimensional model of a covering shell covering the valve body structure externally based on the structural information of the valve body structure; S4: dividing the three-dimensional model of the covering shell into different regions, and obtaining position information and structural information of each region; S5: forming a coating shell layer by layer using foundry sand in different regions, bonding and fixing the coating shell and the flow channel green body in all regions to obtain a direct-drive valve casting model, and performing a first post-processing on the direct-drive valve casting model; S6: Casting the material to be formed based on the direct-drive valve casting model to obtain a direct-drive valve blank; S7: performing a demolding process and a second post-processing on the direct-drive valve blank to obtain a direct-drive valve finished product.

[0048] It should be noted that the casting sand has a fixed shape after solidification and degreasing, and has certain structural properties, but its strength is not high and it can be easily destroyed when external force is applied. This method avoids the additive forming of the valve body structure, and thus uses a sand mold that preferentially forms the flow channel structure and the cavity with the valve body structure, and then obtains a complete direct-drive valve blank through casting.

[0049] Specifically, in a specific embodiment of the present invention, a large flow direct-drive valve is formed by combining the above steps: Separate the flow channel cavity part and valve body structure part of the three-dimensional model of the large flow direct-drive valve; The raw sand is triple screened and premixed with 0.25% of a curing agent to obtain foundry sand; The number of layers and structural information of the runner cavity are obtained, and the runner cavity is formed based on the structural information according to the process standard of sand mold printing. The layer thickness is 0.4 mm, the resolution is 0.1 mm, and the sand laying rate is set to 180 mm / s to obtain the runner green body; Use foundry sand to coat the shell in different areas layer by layer, and drip furan resin binder to bond and fix the solidified area of ​​each layer, with the total amount of resin added being 1.6% of the total amount of foundry sand; After all layers are bonded, a hollow direct-drive valve casting model with a flow channel model but lacking a valve body structure is obtained. The direct-drive valve casting model is solidified and degreased, and the sand mold dimensional accuracy can be controlled within ± 0.02%; The direct-drive valve casting model is used to directly cast the main body to obtain a direct-drive valve blank, and the flow channel structure inside the main body of the direct-drive valve blank can be formed in one piece; The casting sand inside and outside the direct-drive valve blank is cleaned and sintered to obtain a large-flow direct-drive valve finished product.

[0050] Specifically, the method forms a sand core of a flow channel green body first, then forms a hollow sand mold with a valve body structure, and casts the mold in combination with the sand core. The valve body structure of the direct-drive valve is integrally formed and has its own flow channel. The flow channel and the outer surface of the valve body structure are cleaned of sand and the surface is cleaned to obtain a finished direct-drive valve.

[0051] It can be understood that, through this method, the forming process is simple, and the shape and size of the flow channel are easy to ensure, thereby increasing the overall flow channel ratio in a direct-drive valve of the same volume and reducing the overall weight of the direct-drive valve.

[0052] See also Figure 5 The present invention also proposes a hydraulic direct-drive valve forming method, comprising the following steps: S1: Acquire information of the hydraulic direct-drive valve and construct a three-dimensional model, and perform regional segmentation of a flow channel cavity and a valve body structure forming the flow channel cavity of the three-dimensional model; S2: obtaining structural information of the split flow channel cavity, and using a resin material or a wax material to perform layer-by-layer forming based on the structural information of the flow channel cavity to obtain a flow channel green body; S3: Ceramic material is used to cover the outer periphery of the flow channel green body, and then resin material or wax material is used to form a corresponding valve body structure; S4: constructing a three-dimensional model of a coating shell covering the valve body structure outside the valve body structure, and forming the coating shell using a ceramic material to obtain a direct-drive valve casting model, and performing a first post-processing on the direct-drive valve casting model; S5: Casting the material to be formed based on the direct-drive valve casting model to obtain a direct-drive valve blank; S6: De-modeling and post-processing the direct-drive valve blank for the second time to obtain a direct-drive valve finished product.

[0053] It should be noted that the resin material or wax material of the formed flow channel green body and the valve body structure has poor high temperature resistance, but at conventional process temperatures, its structural performance is strong, not easy to deform, and can support the forming of the flow channel cavity and the covering shell; The ceramic material on the periphery of the flow channel green body and the ceramic material covering the valve body structure can be obtained by repeated coating and cooling. The ceramic material is resistant to high temperature, has good structural properties, can support the casting of the valve body, and the material is more brittle after cooling, and can efficiently destroy the outer surface of the valve body structure and even the flow channel green body to achieve peeling.

[0054] Specifically, in a specific embodiment of the present invention, a large flow direct-drive valve is formed by combining the above steps: Separate the flow channel cavity part and valve body structure part of the three-dimensional model of the large flow direct-drive valve; The cavity of the flow channel is formed layer by layer using zirconia ceramic material with a layer thickness of 0.1 mm, forming an outer skin of 0.5 mm and an internal body-centered cubic lattice with a unit cell side length of 5 mm. In addition, a 2 mm area is selected at the flow channel branch to partially cancel the internal lattice of the skin, making the flow channel model a flow channel green body that is loose as a whole and has local fragile breakpoints. Obtaining position information and structural information of each area of ​​the split valve body structure; Composite additive manufacturing technology is used to form zirconia ceramic material on the surface of the flow channel green body in each area, and paraffin stearic acid mixed wax combined with wax mold printing forming process is used to form the valve body structure layer by layer in different areas, with a layer thickness of 0.1 mm. Different adhesive materials are dripped between the surface of the flow channel green body and different layers of the valve body structure, so that the two powder materials corresponding to the shell and the flow channel are combined in blocks, and then the shell and the flow channel of the next layer are combined in regions. After all layers are formed, the valve body structure of the wax material and the flow channel green body of the ceramic material are obtained; The valve body structure is used as the investment mold core, and the runner green body is embedded in the shell as the internal refractory material of the investment casting and is solidified as a whole; Several layers of ceramic material are applied to the outer surface of the shell investment mold core. After the outer ceramic material is hardened and dried, the investment mold core of the valve body structure is heated and melted to form a refractory hollow shell, which is then sintered at high temperature. After casting the hollow shell, physical knocking and vibration impact are used to break the refractory ceramic materials on the outside and inside of the casting, the casting is taken out to clean the debris, and the casting is subjected to solid solution-aging heat treatment to obtain a finished large-flow direct-drive valve.

[0055] Specifically, the method forms a flow channel blank first, forms a high temperature resistant ceramic material on the outer surface, then forms a valve body structure outside the flow channel blank, and then forms a high temperature resistant ceramic material on the outer surface of the valve body structure to form a covering shell; During the solidification and degreasing process, the wax material that is not resistant to high temperatures melts or evaporates, leaving behind a hollow coated shell with a flow channel cavity. The hollow shell is then cast to form a direct-drive valve blank, and then the flow channel cavity and the outer surface of the valve body structure are cleaned to obtain a finished direct-drive valve.

[0056] It can be understood that through this method, the flow channel is also formed first, and then the valve body structure is formed. However, the high-temperature resistance of the wax material is utilized to make it melt or even volatilize when heated, leaving behind a covering shell of the valve body structure with a flow channel cavity, which is then formed through casting and post-processing to obtain a finished direct-drive valve. The process is simple, and the shape and size of the flow channel are controllable.

[0057] See also Figure 6 The present invention also proposes a hydraulic direct-drive valve forming method, comprising the following steps: S1: Acquire information of the hydraulic direct-drive valve and construct a three-dimensional model, and perform regional segmentation of a flow channel cavity and a valve body structure forming the flow channel cavity of the three-dimensional model; S2: obtaining structural information of the split flow channel cavity, and using foundry sand to perform layer-by-layer forming based on the structural information of the flow channel cavity to obtain a flow channel green body; S3: Acquire structural information of the valve body structure, and externally construct a three-dimensional model of a covering shell covering the valve body structure based on the structural information of the valve body structure; S4: using a resin material or a wax material to form a valve body structure, and using a ceramic material to form the covering shell outside the valve body structure to obtain a direct-drive valve casting model, and performing a first post-processing on the direct-drive valve casting model; S5: Casting the material to be formed based on the direct-drive valve casting model to obtain a direct-drive valve blank; S6: De-modeling and post-processing the direct-drive valve blank for the second time to obtain a direct-drive valve finished product.

[0058] The hydraulic direct-drive valve forming method is a composite additive forming of the first two forming methods, and the details are not described here. Since the hydraulic direct-drive valve forming method combines the above-mentioned sand casting and investment casting technical solutions, it at least has all the beneficial effects brought by the technical solutions of the above-mentioned sand casting and investment casting embodiments, and will not be described here one by one.

[0059] See also Figure 7 The present invention also proposes a hydraulic direct drive, 1, which is formed by a hydraulic direct drive valve forming method as described above. The hydraulic direct drive valve is provided with a combination interface for use with other valves, and is used to combine with other valves to expand the flow level.

[0060] It should be noted that the hydraulic direct-drive valve 1 is used in conjunction with other valves through a combined interface, and the flow level of the combined structure is expanded when the liquid flow rate itself increases. In addition, since the volume itself remains unchanged and the weight is reduced, the applicability of the combined structure is expanded.

[0061] It should be understood that the "one implementation method" or "one embodiment" mentioned throughout the specification means that the specific features, structures or characteristics related to the embodiment are included in at least one embodiment of the present invention. Therefore, "in one implementation method" or "in one embodiment" appearing throughout the specification does not necessarily refer to the same embodiment. In addition, these specific features, structures or characteristics can be combined in one or more embodiments in any suitable manner. Those skilled in the art should also be aware that the embodiments described in the specification are all optional embodiments, and the actions and modules involved are not necessarily required by the present invention.

[0062] In various embodiments of the present invention, it should be understood that the size of the serial numbers of the above-mentioned processes does not mean the necessary order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.

[0063] The flow chart and block diagram in the accompanying drawings of the present invention illustrate the possible architecture, function and operation of the system, method and computer program product according to various embodiments of the present application. In this regard, each box in the flow chart or block diagram can represent a module, a program segment or a part of a code, and the module, the program segment or a part of the code contains one or more executable instructions for realizing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the box can also occur in a sequence different from that marked in the accompanying drawings. For example, two boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, which is determined based on the functions involved. It should be particularly noted that each box in the block diagram and / or flow chart, and the combination of the boxes in the block diagram and / or flow chart can be implemented by a dedicated hardware-based system that performs a specified function or operation, or can be implemented by a combination of dedicated hardware and computer instructions.

[0064] The above description is only an exemplary embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the technical concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A method for forming a hydraulic direct-drive valve, characterized in that: The steps include: Acquire information of the hydraulic direct-drive valve and construct a three-dimensional model, and perform regional segmentation of a flow channel cavity and a valve body structure forming the flow channel cavity of the three-dimensional model; Acquiring structural information of the split flow channel cavity, and performing layer-by-layer forming based on the structural information of the flow channel cavity to obtain a flow channel green body; Acquiring structural information of the valve body structure, and constructing a three-dimensional model of a covering shell covering the valve body structure externally based on the structural information of the valve body structure; Forming the coating shell layer by layer, bonding and fixing the coating shell and the flow channel green body to obtain a direct-drive valve casting model, and performing a first post-processing on the direct-drive valve casting model; Casting is performed based on the direct-drive valve casting model to obtain a direct-drive valve blank; The direct-drive valve blank is subjected to a demolding process and / or a second post-processing to obtain a direct-drive valve finished product.

2. The method for forming a hydraulic direct-drive valve according to claim 1, characterized in that: The first post-processing includes the steps of solidification and degreasing of the direct-drive valve casting model; the model removal process includes the subtractive process of the flow channel green body and / or the coating shell; the second post-processing includes the flow channel cleaning and / or overall sintering steps of the direct-drive valve blank.

3. The method for forming a hydraulic direct-drive valve according to claim 1, characterized in that: The cross-sectional shape of the flow channel cavity can be any one of a circle, an ellipse, a teardrop, a regular polygon or an oblique polygon.

4. The method for forming a hydraulic direct-drive valve according to claim 1, characterized in that: The flow channel cavity comprises a main channel and a branch channel extending from the main channel, and the angle between the branch channel and the axial extension direction of the main channel is 10°-170°.

5. The method for forming a hydraulic direct-drive valve according to claim 4, characterized in that: The maximum cross-sectional distance of the main channel is 12 mm-100 mm, and the minimum cross-sectional distance of the branch channel at the end is 1 mm~30 mm; the cross-sectional distance of the branch channel in the same direct drive valve decreases as the number of branches increases.

6. The method for forming a hydraulic direct-drive valve according to claim 4, characterized in that: The number of branches of the same branch channel in the direct-drive valve is 2-10, and the connection points of two adjacent branches are smoothly connected.

7. A method for forming a hydraulic direct-drive valve, characterized in that: The steps include: Acquire information of the hydraulic direct-drive valve and construct a three-dimensional model, and perform regional segmentation of a flow channel cavity and a valve body structure forming the flow channel cavity of the three-dimensional model; Acquire structural information of the split flow channel cavity, and use foundry sand to perform layer-by-layer forming based on the structural information of the flow channel cavity to obtain a flow channel green body; Acquiring structural information of the valve body structure, and constructing a three-dimensional model of a covering shell covering the valve body structure externally based on the structural information of the valve body structure; Divide the three-dimensional model of the covering shell into different areas, and obtain the position information and structure information of each area; The coating shell is formed layer by layer using foundry sand in different regions, the coating shell and the flow channel green body of all regions are bonded and fixed to obtain a direct-drive valve casting model, and the direct-drive valve casting model is subjected to a first post-processing; Based on the direct-drive valve casting model, the material to be formed is used for casting to obtain a direct-drive valve blank; The direct-drive valve blank is subjected to model removal and a second post-processing to obtain a direct-drive valve finished product.

8. A method for forming a hydraulic direct-drive valve, characterized in that: The steps include: Acquire information of the hydraulic direct-drive valve and construct a three-dimensional model, and perform regional segmentation of a flow channel cavity and a valve body structure forming the flow channel cavity of the three-dimensional model; Acquiring structural information of the split runner cavity, and using a resin material or a wax material to perform layer-by-layer forming based on the structural information of the runner cavity to obtain a runner green body; The outer periphery of the flow channel green body is coated with ceramic material, and then a corresponding valve body structure is formed with resin material or wax material; Constructing a three-dimensional model of a coating shell covering the valve body structure outside the valve body structure, and forming the coating shell using a ceramic material to obtain a direct-drive valve casting model, and performing a first post-processing on the direct-drive valve casting model; Based on the direct-drive valve casting model, the material to be formed is used for casting to obtain a direct-drive valve blank; The direct-drive valve blank is subjected to model removal and a second post-processing to obtain a direct-drive valve finished product.

9. A method for forming a hydraulic direct-drive valve, characterized in that: The steps include: Acquire information of the hydraulic direct-drive valve and construct a three-dimensional model, and perform regional segmentation of a flow channel cavity and a valve body structure forming the flow channel cavity of the three-dimensional model; Acquire structural information of the split flow channel cavity, and use foundry sand to perform layer-by-layer forming based on the structural information of the flow channel cavity to obtain a flow channel green body; Acquiring structural information of the valve body structure, and constructing a three-dimensional model of a covering shell covering the valve body structure externally based on the structural information of the valve body structure; Using a resin material or a wax material to form a valve body structure, and using a ceramic material to form the covering shell outside the valve body structure to obtain a direct-drive valve casting model, and performing a first post-processing on the direct-drive valve casting model; Based on the direct-drive valve casting model, the material to be formed is used for casting to obtain a direct-drive valve blank; The direct-drive valve blank is subjected to model removal and a second post-processing to obtain a direct-drive valve finished product.

10. A hydraulic direct-drive valve formed by a hydraulic direct-drive valve forming method according to any one of claims 1 to 9, characterized in that: The hydraulic direct-drive valve is provided with a combination interface for use with other valves, and is used for combining with other valves to expand the flow level.

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