Method and device for efficiently pressing shell and armature assembly

Abstract

The invention belongs to the technical field of electro-hydraulic servo valve design and assembly, and particularly relates to a method and device for efficiently pressing a shell and an armature assembly, and the method comprises the following steps: (1) preparing the armature assembly and the shell; (2) the armature assembly in the step (1) is installed on the left middle portion of an armature fixing base of a combined clamp, the distance L between the bottom face of an armature and a spring tube is measured before installation, and a gasket with the corresponding thickness is selected to be installed below the armature assembly; (3) assembling and clamping the left armature fixing seat and the right armature fixing seat through taper pins, and fixing the left armature fixing seat and the right armature fixing seat through locking nuts; (4) the assembly body obtained in the step (3) and the shell are installed, it is guaranteed that the shell is flush with the clamp, then the clamp is placed on a vertical drilling machine, the lower surface of the shell is pressed through a special pressing head, the shell is pressed into the armature assembly, and a shell assembly is formed; (5) disassembling the locking nut and the taper pin, separating the left armature fixing seat from the right armature fixing seat, and taking out the shell assembly; and (6) measuring the parallelism and the height dimension H of the shell assembly.

Description

Technical Field

[0001] This invention belongs to the field of electro-hydraulic servo valve design and assembly technology, specifically relating to a method and apparatus for efficiently pressing together a housing and an armature assembly. Background Technology

[0002] The single-stage spray-baffle servo valve mainly consists of a housing, armature assembly, nozzle assembly, and coil assembly. The coil assembly is installed within the armature assembly, and the coil and nozzle assemblies are installed within the housing, meeting specific form and position tolerances and dimensional tolerances. Specifically, the parallelism between the armature plane and the housing plane in the armature assembly must meet 0.01, and the height dimension H must meet ±0.01. The parallelism between the baffle and the housing end face in the armature assembly must meet 0.005. The single-stage spray-baffle servo valve has high precision requirements; deviations in form and position tolerances during installation will affect the servo valve's performance and function. Among these, the dimensional and position tolerances of the armature assembly installed within the housing have the most direct and significant impact on the performance of the single-stage spray-baffle servo valve.

[0003] During assembly, on the one hand, the armature assembly and the housing need to ensure precise flatness. On the other hand, since the wall thickness of the spring tube in the armature assembly is only 0.01mm, the traditional assembly method, where the housing is much heavier and larger than the armature assembly, typically involves fixing the housing to a flat surface and pressing the armature assembly downwards using the upper surface of the housing as a reference until it is pressed into the ideal position. This assembly method is prone to spring tube breakage during the pressing process. At the same time, it is difficult to ensure the flatness between the armature assembly and the housing, resulting in a low assembly qualification rate. Because the flatness between the armature assembly and the housing cannot meet the accuracy requirements, the product's hysteresis, resolution, linearity, and flow curve are unqualified, seriously affecting the product qualification rate. This invention relates to a process method for high-efficiency pressing of the housing and armature assembly. The armature assembly is fixed in the armature mounting base, and the radius (R) of the spring tube is aligned with the radius (R) of the armature mounting base. The armature mounting base guides the housing for pressing, and the dimensional height is adjusted by using shims to achieve high-efficiency pressing. This method ensures the drawing tolerances and dimensional tolerances, and guarantees the first-time assembly and adjustment pass rate of the single-stage spray baffle servo valve. Summary of the Invention

[0004] To address the challenges of assembling the armature assembly and housing of a single-stage spray baffle servo valve, avoid damage to the thin-walled spring tube, and ensure the relative parallelism and dimensions of the armature assembly and housing, this invention proposes a highly efficient pressing process for the housing and armature assembly. This improves pressing assembly efficiency and the first-time assembly and adjustment pass rate of the single-stage spray baffle servo valve.

[0005] A method for efficiently pressing together a housing and an armature assembly, the pressing method comprising the following steps: ①Preparation of armature assembly and housing; ② Install the armature assembly from step ① into the armature fixing seat - left in the combination fixture. Before installing the fixture, measure the distance L between the bottom surface of the armature and the spring tube, and select the appropriate shims to install below the armature assembly. ③ Install and clamp the left armature fixing seat and the right armature fixing seat from step ② using tapered pins and secure them with lock nuts; ④ Install the parts from step ③ onto the housing, ensuring that the housing is flush with the fixture. Place the fixture on a vertical drilling machine and use a special pressure head to press the lower surface of the housing into the armature assembly to form the housing assembly. ⑤ Remove the locking nut from the tapered pin in step ④, pull out the tapered pin, disassemble the left armature retainer and the right armature retainer, and remove the housing assembly. ⑥ Measure the parallelism and height dimension H of the disassembled housing assembly from step ⑤. Furthermore, the shell is manufactured in a manner that requires the parallelism of the upper and lower surfaces to be within 0.005, the flatness to be within 0.005, and the axial dimensional tolerance to be within 0.01.

[0006] Furthermore, the armature assembly and the housing are reversed and pressed together, and the housing is pressed into the armature assembly to protect the thin wall of the spring tube in the armature assembly.

[0007] Furthermore, the housing assembly pressing fixture consists of an armature fixing seat-left 1, an armature fixing seat-right 2, a thickness adjustment block 4, a tapered pin 6, a locking nut 7, etc. The armature assembly 5 is installed in the armature fixing seat-left 1 and the armature fixing seat-right 2. The armature assembly 5 is clamped by the tapered pin 6 and locked by the locking nut 7 to prevent it from falling off during the pressing process.

[0008] Furthermore, the armature fixing seat-left 1 and armature fixing seat-right 2 are machined as a single piece using slow-speed machining to ensure that the flatness of the groove and the perpendicularity of the groove surface are within 0.003. After machining, the armature fixing seat is cut into armature fixing seat-left 1 and armature fixing seat-right. The φ3.7 in armature fixing seat-left 1 and armature fixing seat-right 2 is machined using slow-speed wire cutting, and the R-angle of the hole is formed using special tooling.

[0009] Furthermore, the grooves formed by the housing 3 and the armature fixing seat-left 1 and armature fixing seat-right 2 are micro-gap, with the gap controlled within 0.01, to prevent the housing from tilting during the pressing process and causing over-cutting between the housing 3 and the armature assembly 5.

[0010] Furthermore, the R-angle of the φ3.7 orifice formed by the spring tube in the armature assembly 5 and the armature fixing seat-left 1 and armature fixing seat-right 2 serves as a positioning surface, which contacts the R-angle of the spring tube in the armature assembly 5 and avoids the thin wall of the spring tube in the armature assembly.

[0011] Furthermore, in the armature assembly 5, the armature is flush with and locked in place with the grooves formed by the armature fixing seat-left 1 and the armature fixing seat-right 2, ensuring that the flat part in the armature assembly 5 does not rotate.

[0012] Furthermore, the flat part in the armature assembly 5 is machined in the armature assembly to ensure that the flat part in the armature assembly is perpendicular to the two ends of the armature in the armature assembly.

[0013] The present invention employs a multi-stage pressing method for the housing until the housing is pressed flat against the thickness adjustment block 4, ensuring the H dimension; In the pressing method of the present invention, the key steps are as follows: ① Prepare the armature assembly and the housing. The symmetry of the armature assembly must meet 0.003, and the form and position tolerance of the housing surface must meet 0.005. ② Install the armature assembly from step ① into the armature fixing seat - left in the combination fixture. Before installing the fixture, measure the distance L between the bottom surface of the armature and the spring tube, and select the appropriate shims to install below the armature assembly. ③ Install and clamp the left armature fixing seat and the right armature fixing seat from step ② using tapered pins and secure them with lock nuts; ④ Install the parts from step ③ onto the housing, ensuring that the housing is flush with the fixture. Place the fixture on a vertical drilling machine and use a special pressure head to press the lower surface of the housing into the armature assembly to form the housing assembly. ⑤ Remove the locking nut from the tapered pin in step ④, pull out the tapered pin, disassemble the left armature retainer and the right armature retainer, and remove the housing assembly. ⑥Measure the parallelism and height dimension H of the disassembled housing assembly from step ⑤.

[0014] Beneficial technical effects: The device and pressing method designed in this invention can accurately fix the armature assembly, and the pressing shell can reduce the clamping and alignment time, improve processing efficiency, and reduce the risk of damage to thin-walled parts. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. The drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 A schematic diagram of a process for a high-efficiency press-fitting method for housing and armature assembly; Figure 2 A schematic diagram of the overall structure of a process for efficiently pressing together a housing and an armature assembly; Figure 3 This is a schematic diagram of the armature fixing seat (right side) in a process for efficiently pressing together a housing and an armature assembly. Figure 4 This is a schematic diagram of the armature assembly structure in a process for efficiently pressing together a housing and an armature assembly. Figure 5 This is a schematic diagram of the positioning structure in a process for efficiently pressing together a housing and an armature assembly. Figure 6 This is a schematic diagram of the shell assembly structure after pressing, which is part of a process for efficiently pressing a shell and an armature assembly.

[0017] Among them, 1-armature fixing seat-left, 2-armature fixing seat-right, 3-shell, 4-thickness adjustment block, 5-armature assembly (5-1 baffle, 5-2 armature, 5-3 spring tube), 6-tapered pin, 7-locking nut. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] The features and illustrative embodiments of various aspects of the present invention will now be described in detail. Numerous specific details are set forth in the following detailed description to provide a thorough understanding of the invention. However, it will be apparent to those skilled in the art that the invention may be practiced without requiring some of these specific details. The following description of embodiments is merely intended to provide a better understanding of the invention by illustrating examples of the invention. The invention is by no means limited to any specific setups and methods set forth below, but covers any improvements, substitutions, and modifications to structures, methods, and devices without departing from the spirit of the invention. Well-known structures and techniques are not shown in the drawings and the following description to avoid unnecessarily obscuring the invention.

[0020] In the description of this invention, it should be noted that the directions or positional relationships indicated by terms such as "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer" are based on the directions or positional relationships shown in the accompanying drawings and are only for the convenience of describing and simplifying the invention, and should not be construed as limiting the invention. Furthermore, the use of ordinal numbers (e.g., "first and second," etc.) is for distinguishing objects and is not limited to this order, and should not be construed as indicating or implying relative importance.

[0021] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly, encompassing both direct connection and indirect connection via an intermediate medium. Those skilled in the art can understand the specific meaning of these terms in this invention based on the specific circumstances.

[0022] It should be noted that, unless otherwise specified, the embodiments of the present invention and the features thereof can be combined with each other, and the various embodiments can be referenced and cited in each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0023] The present invention will be further described in detail below with reference to the embodiments and accompanying drawings, but the embodiments of the present invention are not limited thereto.

[0024] like Figures 1-6 As shown, this invention application provides a process method for efficiently pressing together the housing and armature assembly, as follows: Figure 1 As shown, the main processes include: preparing the armature assembly and the housing; the symmetry of the armature assembly must meet 0.003, and the surface form and position tolerance of the housing must meet 0.005; installing the armature assembly in the assembly fixture, specifically the left armature fixing seat; before installing the fixture, measuring the distance L between the bottom surface of the armature and the spring tube, and selecting appropriate shims to install below the armature assembly; clamping the left and right armature fixing seats with tapered pins and securing them with lock nuts; installing the housing, ensuring it is flush with the fixture, and placing the fixture on a vertical drilling machine; pressing the lower surface of the housing with a special pressure head to press the housing into the armature assembly, forming the housing assembly; removing the lock nut from the tapered pin and pulling out the tapered pin; disassembling the left and right armature fixing seats; removing the disassembled housing assembly and measuring its parallelism and height dimension H. The specific process route is as follows: part preparation - grinding - cleaning - assembling the armature assembly - pressing the housing assembly - inspection - warehousing.

[0025] This invention application provides a schematic diagram of the fixture structure in a process method for efficiently pressing together a housing and an armature assembly, as shown below. Figure 2 As shown, the device includes an armature fixing seat-left 1, an armature fixing seat-right 2, a thickness adjustment block 4, a tapered pin 6, a locking nut 7, etc. The armature assembly 5 is installed in the armature fixing seat-left 1 and the armature fixing seat-right 2. The upper ends of the armature fixing seat-left 1 and the armature fixing seat-right 2 are provided with stepped notches. The two fixing seats are provided with armature assembly mounting cavities at a certain distance downward along the stepped surfaces. After the armature fixing seat-left 1 and the armature fixing seat-right 2 are aligned, their upper ends form the mounting groove of the servo valve housing 3. The housing can move up and down along the mounting groove. The mounting cavity is used to fix and constrain the armature assembly.

[0026] In the specific implementation process, the armature assembly 5 is installed in the armature fixing seat-left 1 and the armature fixing seat-right 2, and is clamped by the tapered pin 6 and locked by the locking nut 7 to prevent it from falling off during the pressing process. In the specific implementation process, after the armature fixing seat-left 1 and armature fixing seat-right 2 are aligned, the upper end forms the mounting groove of the servo valve housing; the housing can move up and down along the mounting groove.

[0027] In the specific implementation process, the housing 3 is flush with the fixture, and the fixture is placed on a vertical drilling machine. A special pressure head is used to press the lower surface of the housing to press the housing into the armature assembly to form the housing assembly. The key dimension H and geometric tolerances in the housing assembly are measured.

[0028] See appendix Figure 1 To better complete the assembly of the injection baffle servo valve, this invention designs a device for efficiently pressing together the housing and armature assembly. This device includes... 1. The armature fixing seat is machined as a single piece. After machining, it is divided into left and right armature fixing seats. The grooves and holes in the armature fixing seat are machined on a slow wire EDM machine using the external shape as a reference, ensuring that the perpendicularity, flatness, and hole diameter dimensions in the fixture are within 0.005. Figure 3 As shown; 2. The positioning of the press-fit housing and armature assembly is achieved using radius (R) positioning. The R-angle of the φ3.7 orifice in the fixture is designed based on the R-angle of the thin-walled section of the spring tube 5-3, ensuring a close fit with the R-angle of the thin-walled section of the spring tube 5-3, without damaging the spring tube. The consistency of the R-angle orifice must also meet certain requirements. For example... Figure 5 As shown; 3. During the installation of armature 5-2 in the armature assembly, it is necessary to ensure that both ends of the armature are flush with the slots in the armature fixing seat and that rotation is not allowed. The armature assembly must have a limiting function. 4. The shell is pressed together in multiple stages until it is flush with the thickness adjustment block 4, ensuring the H dimension; 5. The grooves formed by the housing 3 and the armature fixing seat-left 1 and armature fixing seat-right 2 are micro-gap, and the gap is controlled within 0.01 to prevent the housing from tilting during the pressing process, which would cause over-cutting between the housing 3 and the armature assembly 5; 6. For different heights and armature assembly dimensions L, the H dimension can be guaranteed by selecting an appropriate thickness adjustment block 4. The thickness adjustment block 4 is processed in increments of 0.005μm and the corresponding serial number is engraved on it.

[0029] Example 1: A device for pressing together a housing and an armature assembly, the device comprising an armature fixing seat-left 1, an armature fixing seat-right 2, a thickness adjustment block 4, a tapered pin 6, a locking nut 7, etc., the armature assembly 5 is installed in the armature fixing seat-left 1 and the armature fixing seat-right 2; both the armature fixing seat-left 1 and the armature fixing seat-right 2 have stepped notches at their upper ends, and the two fixing seats have armature assembly mounting cavities at a certain distance downward along the stepped surfaces. After the armature fixing seat-left 1 and the armature fixing seat-right 2 are aligned, their upper ends form a mounting groove for the servo valve housing 3; the housing can move up and down along the mounting groove; the mounting cavity is used to fix and constrain the armature assembly.

[0030] The armature assembly 5 is installed in the armature fixing seat-left 1 and armature fixing seat-right 2, and is clamped by the tapered pin 6 and locked by the locking nut 7 to prevent it from falling off during the pressing process. After the armature fixing seat-left 1 and armature fixing seat-right 2 are aligned, their upper ends form the mounting groove for the servo valve housing; the housing can move up and down along the mounting groove. The housing 3 is flush with the fixture, and the fixture is placed on a vertical drilling machine. A special pressure head is used to press the lower surface of the housing into the armature assembly to form the housing assembly.

[0031] A method for pressing together a jet baffle servo valve housing 3 and an armature assembly 5, the pressing method comprising the following steps: Precision-machined state feedback rod, armature, and Bourdon tube parts are prepared. The parts are machined and drawn using mechanical pressing. A fixing fixture is designed and manufactured based on the dimensions and structure of the armature assembly and housing. This fixture first uses slow wire cutting to machine the housing pressing groove, then divides the fixture in two along the centerline. After assembly, a square hole is machined using slow wire cutting to fix the flat surface of the armature, ensuring a parallelism of 0.02. A circular through hole is machined using fast wire cutting, and the hole opening is rounded to utilize the diameter difference to constrain the armature assembly. The fixture also protects the easily damaged thin wall of the Bourdon tube. The armature assembly is placed in the fixture, and threaded tapered pins are installed through two machined tapered pin holes to clamp the two parts of the fixture. The housing surface hole is aligned with the mating surface of the armature assembly and pressed into the housing pressing groove. After pressing to the bottom, the tapered pins are removed, and the two parts of the fixture are separated to complete the pressing process.

[0032] The above detailed embodiments are a description of the present invention. It should not be considered that the specific embodiments of the present invention are limited to these descriptions. For those skilled in the art, several simple deductions and substitutions can be made without departing from the concept of the present invention, and all of these should be considered to fall within the protection scope of the present invention.

Claims

1. A method of efficiently press bonding a case and an armature assembly, characterized by, It comprises the following steps: ①Preparation of the armature assembly and the shell; ②The armature assembly in step 1 is installed in the armature fixing seat-left and the armature fixing seat-right of the combined clamp, and the distance L between the bottom surface of the armature and the spring tube is measured before installation, and a gasket with corresponding thickness is installed under the armature assembly; ③The armature fixing seat-left and the armature fixing seat-right are assembled and clamped by taper pin, and are fixed by locking nut; ④The assembly obtained in step 3 is installed with the shell, and the shell is ensured to be flush with the clamp, then the clamp is placed on the vertical drilling machine, the lower surface of the shell is pressed by the special pressure head, and the shell is pressed into the armature assembly to form a shell assembly; ⑤The locking nut and the taper pin are disassembled, the armature fixing seat-left and the armature fixing seat-right are separated, and the shell assembly is taken out; ⑥The parallelism and the height dimension H of the shell assembly are measured.

2. The method of claim 1, wherein, In step 1, the parallelism of the upper and lower surfaces of the shell is ≤0.005, the flatness is ≤0.005, and the axial dimension tolerance is ≤0.01; the symmetry of the armature assembly is ≤0.

003.

3. The method of claim 1, wherein the compression of the shell and armature assembly is performed by a press. In step 4, the reverse pressing method is adopted, that is, the shell is pressed into the armature assembly by pressing the shell, so as to protect the thin wall of the spring tube with a wall thickness of only 0.01 mm in the armature assembly.

4. The method of claim 1, wherein the compression of the shell and armature assembly is performed by a press. The combined clamp is composed of the armature fixing seat-left, the armature fixing seat-right, the thickness adjusting block, the taper pin and the locking nut; the armature assembly is installed in the installation cavity formed by the armature fixing seat-left and the armature fixing seat-right, and is clamped by the taper pin and locked by the locking nut to prevent the armature assembly from falling off during pressing.

5. The method of claim 4, wherein the plunger is formed by stamping the plunger from a sheet of magnetic material. The armature fixing seat-left and the armature fixing seat-right are manufactured by integral machining and then separated by cutting, and the slow wire process is adopted during machining to ensure that the flatness in the groove and the perpendicularity of the groove surface are ≤0.003; the φ3.7 hole on both is machined by slow wire, and the R angle of the hole is formed by special tooling.

6. The method of claim 1, wherein, In step 4, the gap between the shell and the groove formed by the armature fixing seat-left and the armature fixing seat-right is ≤0.01, which prevents the shell from being tilted during pressing and causing the shell and the armature assembly to be cut too much.

7. The method of claim 6, wherein the compression of the shell and armature assembly is performed by a press. Step 4 adopts the method of pressing multiple times until the shell is flush with the thickness adjusting block to ensure that the height dimension H meets the requirements.

8. The method of claim 1, wherein, In step 2, the R angle of the spring tube of the armature assembly is positioned with the R angle of the φ3.7 hole of the armature fixing seat-left and the armature fixing seat-right, and avoids the thin wall of the spring tube.

9. The method of claim 1, wherein, A flat structure is machined in the armature assembly, which is perpendicular to the two ends of the armature in the armature assembly; during installation, the armature is flush and fixed with the groove of the armature fixing seat-left and the armature fixing seat-right to prevent the armature assembly from rotating.

10. A press device for implementing the process method according to any one of claims 1 to 9, characterized in that, It comprises the armature fixing seat-left, the armature fixing seat-right, the thickness adjusting block, the taper pin and the locking nut; the upper end of the armature fixing seat-left and the armature fixing seat-right is provided with a stepped gap, and the two are combined to form an armature assembly installation cavity and a shell installation groove; the armature assembly is placed in the installation cavity and is clamped by the taper pin and locked by the locking nut; the shell can move up and down along the shell installation groove, and the thickness adjusting block is used to cooperate with the control of the height dimension H of the shell after pressing.

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