Closed wave spring with protrusions and preparation method of closed wave spring

Abstract

The invention provides a closed wave spring with protrusions and a preparation method thereof.The closed wave spring with the protrusions is in a closed circular ring shape and is provided with a plurality of wave crests and wave troughs which are connected in sequence, and spherical protrusion structures are further arranged on the wave crests and the wave troughs; the preparation method of the closed wave spring with the protrusion comprises the following steps of a) material selection and preparation, b) blanking, c) cutting, d) wave shape forming, e) boss forming, f) turning of the inner circle and the outer circle, and g) aging shaping. According to the method, linear cutting or laser cutting blanking is adopted, shrinkage allowance is reserved for subsequent forming, compensation of the diameter size of the inner circle and the diameter size of the outer circle is guaranteed, waveforms and protrusions are formed in two steps through the mold, and the radial position precision of the protrusions is guaranteed; the situation that the protrusion position changes due to the fact that the material flows towards the radial circle center direction when the waveform is formed in the protrusion size is avoided, and the phenomenon that when the material fluidity is poor, the protrusion cracks possibly, and the phenomena of shrinkage, misrun and bulge deviation near the protrusion possibly occur are avoided.

Description

Technical Field

[0001] The invention relates to the field of springs, and in particular to a closed-end wave spring with a protrusion and a preparation method thereof. Background Art

[0002] Wave spring is a special spring, also called wave spring for short. It is a thin ring-shaped elastic metal element composed of several wave crests and troughs. It has good elasticity. Wave spring is widely used in aviation parts, motors, textile machinery, hydraulic equipment, automobiles and other industries. It is mainly installed in bearing chambers or holes with suitable specifications. The installation space is very small and it has the special function of reducing noise and vibration.

[0003] Traditional single-layer closed wave springs generally use a mold direct forming and heat treatment process. First, the metal sheet is stamped into a circular blank, and then the die is used to stamp the wave shape in the circular direction. Finally, it is heat treated to make it have rebound performance. Its forming process mainly has the following problems: 1). Single-layer closed wave springs generally need to be formed by inner hole positioning. There is rebound during forming, so the mold wave height needs to be compensated compared to the spring wave height. Radial flow occurs during the material forming process, which makes it difficult to accurately calculate the convex position for compensation during mold design. Figure 1 The figure shows the comparison diagram before and after springback of one-shot forming. 2). Wave and bulge forming will cause large material flow, which needs to be compensated. However, when the waveform and bulge are formed in one shot, the material flow will be more irregular, and the compensation will be more difficult to calculate accurately. In addition, for materials with poor plasticity, cracks will appear at the bulge (such as Figure 2 As shown in the figure), and when the final molding is completed, shrinkage, lack of meat and bulge deviation will appear near the bulge (as shown in the figure). Figure 3 shown).

[0004] Therefore, there is an urgent need for a closed-end wave spring with a protrusion and a preparation method thereof to overcome the above-mentioned technical defects. Summary of the invention

[0005] In order to solve the above technical problems, this patent provides a closed-end wave spring with a protrusion and a preparation method thereof. This high-precision, high-quality, and low-processing difficulty molding method can accurately control the position of the protrusion, avoid cracking at the protrusion, and avoid shrinkage, lack of meat, and bulging and offset near the protrusion.

[0006] In order to achieve the above-mentioned purpose, the present application provides the following technical solutions, providing a closed wave spring with a protrusion, including: a spring sheet, the spring sheet is in the shape of a closed circular ring, the spring sheet has a plurality of crests and troughs connected in sequence, and a spherical protrusion structure is also arranged on the crests and troughs.

[0007] On the other hand, the present application also provides a technical solution, a method for preparing a closed-end wave spring with a protrusion, the preparation method comprising the following steps: a) material selection and preparation, b) cutting, c) cutting, d) wave forming, e) boss forming, f) turning of inner and outer circles, and g) aging and shaping.

[0008] Optionally, in step a), the raw material of the wave spring is an alloy spring steel plate with a thickness of 0.3-0.5 mm, and the main components of the steel plate are: C, Mn, Cr, Ni, Si, Cu, Al, Mo, Ti, Pd, Ce and Fe; the content of impurity P is controlled below 0.03%, and the content of impurity S is controlled below 0.03%.

[0009] Optionally, in step c), the spring steel plate cut in step b) is processed into an annular blank by wire cutting or laser cutting, and the inner and outer diameters of the blank need to retain a preset margin, which can be calculated by simulation or experience.

[0010] Optionally, in step d), the annular blank in step c) is wave-formed using a first mold to form a closed wave spring, and the molding surface of the first mold is molded into a wave shape.

[0011] Optionally, in step d), the number of waves of the first mold adopts the sine and cosine formula corresponding to the closed wave spring with a protrusion, and the height of the wave of the first mold is set with height compensation.

[0012] Optionally, in step d), the first mold is provided with a positioning gap with the inner hole of the annular blank, and the inner hole positioning gap can be obtained by simulation or empirical calculation, and a fixed gap is retained in the first mold to facilitate material flow and final forming limit.

[0013] Optionally, in step d), the first mold is designed with an inner hole limit block to position the inner hole of the annular blank in step b), so as to ensure that the inner hole of the annular blank is limited to shrink after forming, and the annular blank is not cracked during forming.

[0014] Optionally, in step e), a second mold is used to shape the closed wave spring in step d) into a convex shape to form a closed wave spring with convexities, and the molding surface of the second mold is convexities spaced apart from top to bottom.

[0015] Optionally, in the step e), the convex hull position of the second mold is designed to be at a theoretical position.

[0016] Optionally, in step e), the second mold is provided with a positioning gap with the inner hole of the closed wave spring, and the inner hole positioning gap can be obtained by simulation or empirical calculation, and a fixed gap is retained in the second mold to facilitate material flow and final molding limit.

[0017] Optionally, in step e), the second mold is designed with an inner hole limit block to position the inner hole of the closed wave spring in step d), so as to ensure that the inner hole of the closed wave spring is limited to shrink after forming, and the closed wave spring will not crack during forming.

[0018] Optionally, in step f), the bulge and the profile are used for positioning, and the multiple closed wave springs in step e) are stacked and machined to form inner and outer circles. This method can effectively ensure the relative positional relationship between the bulge and the inner and outer circles.

[0019] Optionally, in step g), protrusions and profiles are used for positioning, and the multiple closed wave springs with inner and outer circles machined in step f) are stacked and put into a furnace for heat treatment and shaping.

[0020] Optionally, the method for preparing the raised closed-end wave spring also includes the following steps: h) loading aging, i) deburring, j) fatigue strength test, k) elastic force test, l) marking, m) final inspection, and n) cleaning and packaging.

[0021] Beneficial Effects

[0022] The closed-end wave spring with a protrusion of the present application adopts wire cutting or laser cutting to cut the material, reserves shrinkage margin for subsequent molding, ensures compensation of inner and outer circle diameter dimensions, and forms the waveform and the protrusion separately in two steps through a mold. Compared with traditional one-step molding, it can effectively ensure the radial position accuracy of the bulge, avoid the change of the position of the protrusion caused by the flow of material in the radial direction of the center of the circle when the waveform is formed, and avoid cracking that may occur at the bulge when the material fluidity is poor, and can also avoid shrinkage, lack of meat and bulge deviation near the protrusion.

[0023] In this method, the upper and lower surfaces of the turning fixture are fitted and pressed against the surface of the part to achieve the positioning of the protrusion, and the inner and outer circles are machined at the same time. Several pieces can be stacked for processing, and the number is appropriately adjusted according to the size of the wave spring. This method can effectively ensure the relative position relationship between the protrusion and the inner and outer circles.

[0024] This method has low processing difficulty and high bulge forming accuracy, and is suitable for forming various single-layer closed-end wave springs with bulges and different waveforms. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0026] Figure 1 It is a comparative schematic diagram of a one-step formed closed wave spring before rebound provided by the prior art;

[0027] Figure 2 It is a convex flow diagram of a closed wave spring formed once provided by the prior art;

[0028] Figure 3 It is a schematic diagram of the machining convex offset of the one-step formed closed wave spring provided by the prior art;

[0029] Figure 4 It is a schematic diagram of a two-dimensional structure of a closed wave spring with a protrusion provided in an embodiment of the present application;

[0030] Figure 5 It is a schematic diagram of a three-dimensional structure of a closed-end wave spring with a protrusion provided in an embodiment of the present application;

[0031] Figure 6 It is a schematic diagram of the three-dimensional structure of a closed wave spring after wave forming provided in an embodiment of the present application;

[0032] Figure 7 It is a schematic diagram of the three-dimensional structure of a closed wave spring with a protrusion after a boss is formed provided in an embodiment of the present application;

[0033] Figure 8 It is a schematic diagram of the lower die structure of a closed wave spring die with a protrusion after a boss is formed, as provided in an embodiment of the present application. DETAILED DESCRIPTION

[0034] The present application is further described in detail below in conjunction with the accompanying drawings and examples, but it should be noted that these implementation methods are not limitations of the present application, and equivalent changes or substitutions in functions, methods, or structures made by ordinary technicians in the field based on these implementation methods are all within the scope of protection of the present application.

[0035] In the description of the embodiments of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the creation of the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the creation of the present application.

[0036] In addition, the terms "first", "second", "third", etc. are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the invention of this application, unless otherwise specified, the meaning of "plurality" is two or more.

[0037] The terms "installed", "connected" and "connected" 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 an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the invention of this application can be understood by specific circumstances.

[0038] like Figure 4-5 As shown, a closed wave spring with a protrusion is provided, comprising: a spring sheet, the spring sheet is in the shape of a closed circular ring, the spring sheet has a plurality of wave crests and troughs connected in sequence, and a spherical protrusion structure is also arranged on the wave crests and troughs.

[0039] The above-mentioned closed wave spring with protrusion is often welded and fixed with a base to form an elastic element. The protrusion can be fixed with the corresponding accessories by spot welding. It is mainly used in the field of aviation engine sealing to provide axial elastic force with uniform temperature.

[0040] like Figure 6-8 As shown, a method for preparing a closed-end wave spring with a protrusion is provided, and the preparation method includes the following steps: a) material selection and preparation, b) cutting, c) cutting, d) wave forming, e) boss forming, f) turning the inner and outer circles, and g) aging and shaping.

[0041] In some embodiments, in the step a), the raw material of the wave spring is an alloy spring steel plate with a thickness of 0.3-0.5 mm, and the main components of the steel plate are: C, Mn, Cr, Ni, Si, Cu, Al, Mo, Ti, Pd, Ce and Fe; the content of impurity P is controlled below 0.03%, and the content of impurity S is controlled below 0.03%.

[0042] In some embodiments, the step b) specifically includes combining, drilling, and cutting the alloy spring steel plates in the step a), which can improve production efficiency.

[0043] In some embodiments, in step c), the spring steel plate cut in step b) is processed into an annular blank by wire cutting or laser cutting, and the inner and outer diameters of the blank need to retain a preset margin, which can be calculated by simulation or experience.

[0044] In some embodiments, in step d), the annular blank in step c) is wave-formed using a first mold to form a closed wave spring, and the molding surface of the first mold is molded into a wave shape.

[0045] In some embodiments, in step d), the number of waves of the first mold is calculated using the sine and cosine formulas corresponding to the raised closed wave spring, and the height of the waves of the first mold is set with height compensation.

[0046] In some embodiments, in step d), the first mold is set with an inner hole positioning gap with the annular blank, and the inner hole positioning gap can be obtained by simulation or empirical calculation. A fixed gap is retained in the first mold to facilitate material flow and final forming limit.

[0047] In some embodiments, in step d), the first mold is designed with an inner hole limit block to position the inner hole of the annular blank in step b), so as to ensure that the inner hole of the annular blank is limited to shrink after forming, and the annular blank is not cracked during forming.

[0048] In some embodiments, in step e), a second mold is used to shape the closed wave spring in step d) into a convex shape to form a closed wave spring with a convex shape, and the molding surface of the second mold is convex shapes spaced apart from top to bottom.

[0049] In some embodiments, in the step e), the convex hull position of the second mold is designed to be at a theoretical position.

[0050] In some embodiments, in step e), the second mold is set with a positioning gap with the inner hole of the closed wave spring, and the inner hole positioning gap can be obtained by simulation or empirical calculation. A fixed gap is retained in the second mold to facilitate material flow and final molding limit.

[0051] In some embodiments, in step e), the second mold is designed with an inner hole limit block to position the inner hole of the closed wave spring in step d), thereby ensuring that the inner hole of the closed wave spring is limited to shrink after molding, and does not cause the closed wave spring to crack during molding.

[0052] In some embodiments, in step f), the bulge and the profile are used for positioning, and the multiple closed wave springs in step e) are stacked and machined to form inner and outer circles. This method can effectively ensure the relative positional relationship between the bulge and the inner and outer circles.

[0053] In some embodiments, in step g), protrusions and profiles are used for positioning, and the multiple closed wave springs with inner and outer circles machined in step f) are stacked and put into a furnace for heat treatment and shaping.

[0054] In some embodiments, the preparation method of the closed wave spring with protrusion also includes the following steps: h) loading aging, i) deburring, j) fatigue strength test, k) elastic force test, l) marking, m) final inspection, and n) cleaning and packaging. The closed wave spring with protrusion of the present application adopts wire cutting or laser cutting to cut materials, and reserves shrinkage margin for subsequent molding to ensure compensation of inner and outer circle diameters. The waveform and protrusion are formed separately in two steps by the mold. Compared with the traditional one-step molding, it can effectively ensure the radial position accuracy of the bulge, avoid the change of the protrusion position caused by the flow of the material in the radial direction of the center of the circle when the waveform is formed, and avoid cracking that may occur at the bulge when the material fluidity is poor. It can also avoid shrinkage and meat shortage and bulge displacement near the bulge.

[0055] In this method, the upper and lower surfaces of the turning fixture are fitted and pressed against the surface of the part to achieve the positioning of the protrusion, and the inner and outer circles are machined at the same time. Several pieces can be stacked for processing, and the number is appropriately adjusted according to the size of the wave spring. This method can effectively ensure the relative position relationship between the protrusion and the inner and outer circles.

[0056] This method has low processing difficulty and high bulge forming accuracy, and is suitable for forming various single-layer closed-end wave springs with bulges and different waveforms.

[0057] This preparation method is fully applicable to the processing field of single-layer closed wave springs with protrusions. For those familiar with this field, similar modifications can be easily implemented. Therefore, without violating the general concept defined by the claims and the equivalent scope, the present invention is not limited to the established process flow, processing details and illustrations described here.

[0058] The above is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present application shall be included in the protection scope of the present application. The above is only a preferred implementation of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and variations can be made without departing from the technical principles of the present application, and these improvements and variations should also be regarded as the protection scope of the present application.

Claims

1. A closed wave spring with a protrusion, characterized in that: include: The spring sheet is in the shape of a closed circular ring and has a plurality of wave crests and wave troughs connected in sequence, and a spherical protrusion structure is also arranged on the wave crests and wave troughs.

2. A method for preparing a closed-end wave spring with a protrusion, characterized in that: The preparation method comprises the following steps: a) material selection and preparation, b) material cutting, c) cutting, d) waveform forming, e) boss forming, f) turning inner and outer circles, and g) aging and shaping.

3. A method for preparing a closed-end wave spring with a protrusion as claimed in claim 2, characterized in that: In the step a), the raw material of the wave spring is an alloy spring steel plate with a thickness of 0.3-0.5 mm, and the main components of the steel plate are: C, Mn, Cr, Ni, Si, Cu, Al, Mo, Ti, Pd, Ce and Fe; the content of impurity P is controlled below 0.03%, and the content of impurity S is controlled below 0.03%.

4. A method for preparing a closed-end wave spring with a protrusion as claimed in claim 3, characterized in that: In the step c), the spring steel sheet cut in the step b) is processed into an annular blank by wire cutting or laser cutting, and the inner and outer diameters of the blank retain a preset margin, which can be calculated by simulation or experience.

5. A method for preparing a closed-end wave spring with a protrusion as claimed in claim 4, characterized in that: In the step d), the annular blank in step c) is wave-formed by using a first die to form a closed wave spring, and the forming surface of the first die is molded into a wave shape.

6. A method for preparing a closed-end wave spring with a protrusion as claimed in claim 5, characterized in that: The number of waveforms of the first mold adopts the sine and cosine formulas corresponding to the parts to be processed, and the height of the waveform of the first mold is set with height compensation; the first mold is set with an inner hole positioning gap with the annular blank, and the inner hole positioning gap can be obtained by simulation or empirical calculation, and a fixed gap is retained in the first mold; the first mold is designed with an inner hole limit block to position the inner hole of the annular blank in the step b).

7. A method for preparing a closed-end wave spring with a protrusion as claimed in claim 5, characterized in that: The closed wave spring in step d) is convexly shaped by using a second mold to form a closed wave spring with convexities, and the molding surface of the second mold is convexities spaced apart from each other.

8. A method for preparing a closed-end wave spring with a protrusion as claimed in claim 7, characterized in that: The protrusions and the profiles are used for positioning, and the multiple closed wave springs in step e) are stacked and machined into inner and outer circles.

9. A method for preparing a closed-end wave spring with a protrusion as claimed in claim 8, characterized in that: The protrusions and the profile are used for positioning, and the multiple closed wave springs with inner and outer circles machined in step f) are stacked and put into the furnace for heat treatment and shaping.

10. A method for preparing a closed-end wave spring with a protrusion according to claim 1, characterized in that: The method for preparing a closed-end wave spring with a protrusion also includes the following steps: h) loading and aging, i) deburring, j) fatigue strength test, k) elastic force test, l) marking, m) final inspection, and n) cleaning and packaging.

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