Laminated rubber spring, two-part forming mold and method of manufacture

Abstract

The application discloses a laminated rubber spring, a two-part forming die and a preparation method. The laminated rubber spring comprises coaxially arranged upper and lower metal skeletons, two annular intermediate metal partitions and three rubber layers, the three rubber layers are respectively vulcanized and bonded with adjacent metal components, and are connected into an integrated whole through the axial through holes of the intermediate metal partitions. The forming die comprises an upper die, a lower die and a two-part middle die which is formed by two half-ring middle modules. The two-part middle die forms a circumferentially closed radial positioning surface after being closed, and the radial positioning surface has positioning portions which are respectively matched with the end metal skeletons and the intermediate metal partitions. During preparation, the thickness and quantity of the rubber sheet are determined, the rubber sheet is loaded into the die according to the stacking order, each metal component is positioned with the central axis of the two-part middle die as a common positioning reference, and then pre-pressing, exhaust and vulcanization forming are carried out. The application is beneficial to the consideration of normal load, horizontal shear flexibility and the forming consistency of the multi-layer structure.

Description

Technical Field

[0001] This invention relates to the fields of rubber and metal composite elastic components, flexible load-bearing supports, and compression molding technology, specifically to a laminated rubber spring, a two-part molding die, and a preparation method thereof. Background Technology

[0002] In vibration test benches, mechanical equipment supports, low-resistance guide supports, and flexible load-bearing connection structures, support components often need to withstand large loads applied along the normal direction, while also allowing the supported components to undergo a certain range of reciprocating displacement in the horizontal direction relative to the foundation. When there is skewness in the mounting surface, deflection of the load-bearing foundation, or assembly deviations between adjacent components, the support components should also have a certain degree of adaptability to these deviations to reduce the additional loads caused by rigid constraints.

[0003] Rigid guides, sliders, or rolling guide pairs can limit the direction of movement, but under the combined effects of large normal loads and installation deviations, local stress concentrations may occur at their contact points. The guiding resistance may increase with the degree of misalignment, and in severe cases, jamming may occur. Ordinary solid rubber pads can absorb some vibration and deviations through the elastic deformation of the rubber material, but rubber is nearly incompressible and tends to expand towards its free periphery under normal pressure. Simply increasing the rubber hardness or increasing the bearing area can improve the normal load-bearing capacity, but it usually increases the horizontal shear stiffness simultaneously; simply decreasing the hardness or increasing the thickness can improve horizontal compliance, but it may reduce the stability of the normal dimensions. Therefore, ordinary single-layer rubber components struggle to meet multiple performance requirements simultaneously under conditions of small size, high normal loads, and low horizontal shear stiffness.

[0004] Alternating metal partitions and rubber layers along the normal direction allows for layered constraint of the lateral expansion of the rubber layers using metal components, and enables multiple thin rubber layers to share the horizontal displacement. The performance of this type of laminated rubber component depends not only on the rubber material but also on the effective bearing diameter of the rubber layers, the thickness of each layer, the number of layers, the dimensions of the end skeleton, the dimensions of the intermediate metal partitions, the bonding state between the metal and rubber, and the coaxiality of each layer. In particular, when the thickness of a single rubber layer is only on the order of millimeters, even a slight radial offset or tilt of the intermediate metal partition can cause variations in the circumferential thickness of the same rubber layer, uneven distribution of local rubber volume, or uneven stress at the interface, thereby increasing the dispersion of the finished product's shear stiffness and durability.

[0005] In the compression molding and vulcanization process of laminated rubber components, the end metal skeleton, the intermediate metal partition, and the rubber material to be vulcanized are typically loaded into the mold cavity sequentially. While an integral annular mold can form a continuous outer perimeter, when the outer diameter of the end metal skeleton is larger than the outer diameter of the intermediate laminated area, the inner hole of the integral annular mold restricts the axial insertion of the component and the demolding of the finished product. If local positioning blocks or temporary positioning components are used instead, the positioning references obtained for each metal component may differ, and the local positioning components may also move relative to each other during the pre-compression process as the rubber material flows. If the upper and lower metal skeletons and the intermediate metal partition have different outer diameters, it is difficult to simultaneously achieve suitable positioning fits for each layer of metal components using a cylindrical positioning surface of a single diameter.

[0006] On the other hand, the laminated rubber compound undergoes compression and flow during the mold closing process. If the thickness or amount of rubber in the rubber blank varies significantly, or if the axial pressing positions of the upper and lower molds lack coordinated control with the initial axial position of the intermediate metal partition, unstable interlayer spacing, localized insufficient rubber, excessive rubber overflow, or air trapping at the interface can easily occur. Therefore, to obtain a laminated rubber spring with stable normal load-bearing capacity and horizontal shear performance, it is necessary not only to design the laminated structure and dimensional relationships of the finished product, but also to ensure that the mold positioning structure, rubber blank thickness and quantity, mold assembly sequence, pre-compression venting, and vulcanization conditions form a complete and coordinated technical solution. Summary of the Invention

[0007] The purpose of this invention is to provide a laminated rubber spring, a two-part molding die, and a preparation method to solve the above-mentioned problems in the prior art.

[0008] To achieve the above objectives, the present invention adopts the following technical solution:

[0009] In a first aspect, the present invention provides a laminated rubber spring, comprising an upper metal frame, a first rubber layer, a first intermediate metal partition, a second rubber layer, a second intermediate metal partition, a third rubber layer, and a lower metal frame arranged sequentially along the axial direction;

[0010] The upper metal frame, the first intermediate metal partition, the second intermediate metal partition, and the lower metal frame are coaxially arranged.

[0011] The first rubber layer is vulcanized and bonded to the upper metal skeleton and the first intermediate metal partition, the second rubber layer is vulcanized and bonded to the first intermediate metal partition and the second intermediate metal partition, and the third rubber layer is vulcanized and bonded to the second intermediate metal partition and the lower metal skeleton.

[0012] Both the first intermediate metal partition and the second intermediate metal partition are annular plates with axial through holes. The two axial through holes are coaxially arranged. The rubber materials of the first rubber layer, the second rubber layer and the third rubber layer extend into the two axial through holes and are connected to each other, so that the three rubber layers form an integral rubber body.

[0013] The outer diameters of the upper metal frame and the lower metal frame are both greater than the outer diameters of the first intermediate metal partition and the second intermediate metal partition, and the outer diameters of the first intermediate metal partition and the second intermediate metal partition are both greater than the effective bearing diameter of the three rubber layers.

[0014] Furthermore, both the upper metal frame and the lower metal frame are circular end bearing plates, and the portions of both extending radially beyond the outer periphery of the three rubber layers respectively form annular mounting bearing portions;

[0015] The outer diameters of the first intermediate metal partition and the second intermediate metal partition are equal and smaller than the outer diameters of the upper metal frame and the lower metal frame, and their outer peripheral edges protrude radially from the outer peripheral surface of the three rubber layers.

[0016] The effective bearing diameters of the first rubber layer, the second rubber layer, and the third rubber layer are equal and their outer peripheral surfaces are aligned axially. The main pressure-bearing surfaces of the upper metal frame, the first intermediate metal partition, the second intermediate metal partition, and the lower metal frame are parallel to each other.

[0017] Furthermore, the two axial through holes have the same diameter, and the rubber material located in and between the two axial through holes together forms a central rubber connection part, which is connected to the central regions of the first rubber layer, the second rubber layer and the third rubber layer respectively.

[0018] The first intermediate metal partition and the second intermediate metal partition each form a continuous annular solid portion between their corresponding axial through holes and their outer peripheral edges, and the two intermediate metal partitions are respectively embedded in the integral rubber body.

[0019] Furthermore, the effective bearing diameter of the first rubber layer, the second rubber layer, and the third rubber layer is 78-82 mm, the thickness of a single rubber layer is 2.9-3.1 mm, and the total thickness of the three rubber layers is 8.7-9.3 mm.

[0020] The outer diameter of the upper metal frame and the lower metal frame are both 110-120 mm and the thickness is both 8-12 mm; the outer diameter of the first intermediate metal partition and the second intermediate metal partition are both 84 mm and the thickness is both 1.5-2.5 mm.

[0021] The ratio of the effective bearing diameter to the thickness of the single rubber layer is 25 to 29, and the shape factor of the single rubber layer is 6.2 to 7.3. The shape factor is determined according to the ratio of the effective bearing diameter to four times the thickness of the single rubber layer.

[0022] All three rubber layers are made of natural rubber material, which has a hardness of 45-55 Shore A, a tensile strength of not less than 20 MPa, an elongation at break of not less than 450%, and a permanent deformation at break of not more than 35%.

[0023] Secondly, the present invention provides a two-part molding die for laminated rubber springs, comprising an upper die and a lower die arranged opposite to each other along the axial direction, and a two-part middle die disposed between the upper die and the lower die;

[0024] The two-lobed middle mold includes two semi-annular middle modules that can be separated from each other radially. The two semi-annular middle modules are joined together to form an annular middle mold. The inner circumferential side of the annular middle mold forms a radially closed positioning surface along the circumference.

[0025] The upper mold, the lower mold, and the two-lobed middle mold in a mating state together form a lamination forming cavity for accommodating the laminated rubber spring to be formed. The upper mold and the lower mold are respectively provided with opposing axial pressing surfaces on the side facing the lamination forming cavity.

[0026] The radial positioning surface includes an upper end skeleton positioning part, a first partition positioning part, a second partition positioning part, and a lower end skeleton positioning part distributed sequentially along the axial direction. The upper end skeleton positioning part and the lower end skeleton positioning part have a first radial positioning dimension that matches the outer diameter of the upper metal skeleton and the lower metal skeleton of the laminated rubber spring to be formed. The first partition positioning part and the second partition positioning part have a second radial positioning dimension that matches the outer diameter of the first intermediate metal partition and the second intermediate metal partition of the laminated rubber spring to be formed. The first radial positioning dimension is larger than the second radial positioning dimension.

[0027] Furthermore, each of the semi-annular modules has a radial parting surface at both circumferential ends. The corresponding radial parting surfaces of the two semi-annular modules in the mating state are in contact with each other, and the plane where the radial parting surface is located passes through the central axis of the two-lobed middle mold.

[0028] Each of the semi-circular modules has an upper end skeleton positioning section, a first partition plate positioning section, a second partition plate positioning section and a lower end skeleton positioning section arranged sequentially along the axial direction on its radial positioning surface. Adjacent positioning sections with different radial positioning dimensions are connected by an axially extending support and limiting part.

[0029] Each positioning segment forms a radially extending contact limiting part, which forms a clearance fit or a detachable contact fit with the outer circumferential surface of the corresponding metal component, and the axially supporting limiting part is disposed opposite to the outer edge of the axial end face of the corresponding metal component.

[0030] Furthermore, the first partition positioning part and the second partition positioning part each include an annular positioning groove. Each annular positioning groove is formed by the engagement of two semi-annular grooves respectively disposed on the two semi-annular modules. The annular positioning groove has a groove bottom and groove sidewalls located on both sides of the groove bottom along the axial direction. The groove bottom is used to restrict the corresponding first intermediate metal partition or second intermediate metal partition from moving radially, and the two groove sidewalls are used to restrict the corresponding first intermediate metal partition or second intermediate metal partition from moving axially or tilting.

[0031] The upper mold is provided with an upper pressing boss on the side facing the lower mold, and the lower mold is provided with a lower pressing boss on the side facing the upper mold. The end faces of the upper pressing boss and the lower pressing boss facing each other constitute the axial pressing surface.

[0032] The outer periphery of the upper mold and the lower mold are respectively provided with mold closing positioning holes that are opposite each other along the axial direction, and positioning pins are inserted into the oppositely arranged mold closing positioning holes;

[0033] The upper mold and the lower mold are also respectively provided with a middle mold limiting surface facing the two-lobed middle mold, and the two-lobed middle mold in the mold closing state is axially limited between the two middle mold limiting surfaces.

[0034] Thirdly, the present invention provides a method for preparing a laminated rubber spring, comprising the following steps:

[0035] S1, the compounded rubber is made into first rubber sheets, second rubber sheets and third rubber sheets corresponding to the first rubber layer, the second rubber layer and the third rubber layer respectively, and each rubber sheet is quantitatively cut according to the design volume of a single rubber layer;

[0036] S2, the upper metal frame, the lower metal frame, the first intermediate metal partition and the second intermediate metal partition are surface treated, and rubber and metal adhesive are coated on the surfaces to be bonded and dried. The first intermediate metal partition and the second intermediate metal partition are both annular plates with axial through holes.

[0037] S3, when the molding die including the upper mold, the lower mold and the two semi-circular middle modules are in the open state, the lower metal skeleton, the third rubber sheet, the second intermediate metal partition, the second rubber sheet, the first intermediate metal partition, the first rubber sheet and the upper metal skeleton are stacked on the lower mold in the following order.

[0038] S4, the two semi-annular modules are joined together radially to form a two-lobed middle mold. The circumferential closed radial positioning surface formed after the two semi-annular modules are joined is used to position the outer peripheral edges of the upper metal frame, the lower metal frame, the first intermediate metal partition, and the second intermediate metal partition, respectively. The first radial positioning dimension used to position the upper metal frame and the lower metal frame is larger than the second radial positioning dimension used to position the first intermediate metal partition and the second intermediate metal partition, so that each metal component takes the central axis of the two-lobed middle mold as a common positioning reference.

[0039] S5, the upper mold and the lower mold are closed along the axial direction, and the two axial pressing surfaces are pressed together on the upper metal skeleton and the lower metal skeleton in turn. Pre-pressing and venting and vulcanization molding are performed in sequence, so that the first rubber layer, the second rubber layer and the third rubber layer are vulcanized and bonded to the adjacent metal components respectively, and the rubber material enters the two axial through holes to connect the three rubber layers into one.

[0040] S6. After vulcanization, the upper mold and the lower mold are separated axially, and then the two semi-annular modules are separated radially. The molded laminated rubber spring is then removed, trimmed, and inspected.

[0041] Furthermore, in step S1, the thickness of each rubber sheet is 2.9 to 3.1 mm, the thickness error does not exceed ±0.1 mm, and the amount of rubber corresponding to a single rubber layer does not exceed ±3% of the theoretical amount of rubber.

[0042] The surface treatment in step S2 includes degreasing and roughening or sandblasting. After the surface treatment is completed, the surface of the metal component is cleaned, and then the rubber and metal adhesive is applied and dried.

[0043] In step S4, the initial axial position of the first intermediate metal partition and the second intermediate metal partition is maintained by the axial support limiting part or the annular positioning groove provided on the radial positioning surface, and the axial spacing between adjacent metal components is defined by the thickness and amount of each rubber sheet and the mold closing distance between the two axial pressing surfaces.

[0044] Furthermore, in step S5, the pre-compression pressure is 2-4 MPa, the pre-compression time is 1-10 min, the vulcanization temperature is 145-155℃, the vulcanization time is 150-180 min, and the vulcanization pressure is 6-10 MPa.

[0045] In step S5, a portion of the rubber material is axially connected through the two axial through holes and forms a continuous central rubber joint after vulcanization.

[0046] In step S6, after the upper mold and the lower mold separate axially, the two semi-annular middle modules separate radially, causing the two-lobed middle mold to open from the outer periphery of the laminated rubber spring.

[0047] Compared with the prior art, the present invention has at least the following beneficial effects:

[0048] Compared to ordinary single-layer rubber pads, this embodiment of the invention uses three thin rubber layers and two intermediate metal partitions stacked alternately. Under normal compression, the upper and lower metal frames and the two intermediate metal partitions respectively constrain the lateral expansion of each rubber layer, allowing the normal load to be transmitted through multiple constrained thin rubber layers. When the upper and lower metal frames undergo horizontal relative displacement, the three rubber layers jointly bear the shear deformation, distributing the overall horizontal displacement among the three layers, thereby facilitating a balance between higher normal load-bearing capacity and lower horizontal shear stiffness.

[0049] In this embodiment of the invention, the axial through holes in the two annular intermediate metal partitions allow the three rubber layers to form a single, integrated rubber body after vulcanization via the central rubber connector. This maintains the layered constraint of the metal partitions on each rubber layer while improving the continuity of the rubber body in the central region. The radial dimensional relationship between the upper and lower metal skeletons, the intermediate metal partitions, and the rubber layers also forms an outer peripheral stepped profile that can be positioned separately by a dedicated mold.

[0050] The two-part intermediate mold of this invention can be opened from both radial sides, avoiding the need for the end metal skeleton to pass through the inner hole of the integral intermediate mold axially. This is suitable for components where the outer diameter of the end metal skeleton is larger than the outer diameter of the intermediate stacked area. After the two semi-annular intermediate molds are closed, each positioning part forms a circumferentially closed positioning boundary around the corresponding metal component, and each positioning part shares the same mold central axis. Therefore, this helps to reduce the radial offset and tilt between the end metal skeleton and the intermediate metal partition.

[0051] The embodiments of the present invention achieve coordinated control of the volume, interlayer axial distance, and interface bonding state of each layer of rubber material through fixed thickness and quantity of rubber sheet, radial common positioning, initial axial support of the middle partition plate, axial pressing of the upper / lower mold, and control of pre-pressurization venting and vulcanization parameters. This is beneficial to improving the thickness consistency of the three rubber layers, the bonding quality of the metal-rubber interface, and the stability of the shear stiffness of the finished product.

[0052] Of course, implementing the various technical solutions of this invention does not necessarily require achieving all of the advantages described above at the same time. Attached Figure Description

[0053] 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. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other embodiments can be obtained from these drawings without creative effort.

[0054] Figure 1 This is a schematic diagram of the axial cross-sectional structure of the laminated rubber spring in an embodiment of the present invention;

[0055] Figure 2 This is an axial cross-sectional view of the two-part molding die in the closed state in an embodiment of the present invention.

[0056] Figure 3 This is a normal load-displacement curve of the laminated rubber spring in an embodiment of the present invention;

[0057] Figure 4 This is a diagram showing the horizontal shear force-displacement curve of the laminated rubber spring in an embodiment of the present invention.

[0058] Figure 5 This is a flowchart of the method for preparing a laminated rubber spring in an embodiment of the present invention.

[0059] In the figure: 1-Layered rubber spring; 11-Upper metal frame; 12-Lower metal frame; 13-First intermediate metal partition; 14-Second intermediate metal partition; 15-First rubber layer; 16-Second rubber layer; 17-Third rubber layer; 18-Axial through hole; 21-Upper mold; 22-Lower mold; 23-Two-lobed middle mold; 24-Positioning pin. Detailed Implementation

[0060] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. It should be understood that the following embodiments are only for illustrating the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention. Without departing from the concept of the present invention, any equivalent substitutions or conventional adjustments made by those skilled in the art to the types, proportions, and process parameters of raw materials based on the disclosure of the present invention should fall within the scope of protection of the present invention.

[0061] For ease of description, the direction of extension of the central axis of the laminated rubber spring and the molding die is defined as the axial direction; the direction perpendicular to the central axis and pointing outward from the central axis is defined as the radial direction; and the direction extending around the central axis is defined as the circumferential direction. When installing and using the laminated rubber spring, the axial direction usually corresponds to the normal bearing direction, and any direction perpendicular to the axial direction can be used as the horizontal shear direction. The terms "upper" and "lower" used in this specification are only used to describe the relative positions shown in the attached drawings; the corresponding force functions can be interchanged when the components are installed in an inverted manner.

[0062] For ease of description, the direction of the central axis extending from the laminated rubber spring 1 and its molding die is defined as the axial direction; the direction perpendicular to the central axis and pointing outward from the central axis is defined as the radial direction; and the direction extending around the central axis is defined as the circumferential direction. When the laminated rubber spring 1 is installed and used, the axial direction usually corresponds to the normal bearing direction, and any direction perpendicular to the axial direction can be used as the horizontal shearing direction. The terms "upper" and "lower" used in this specification are only used to describe the relative positions shown in the attached drawings. When the laminated rubber spring 1 or the molding die is flipped, the functions of the corresponding components can be interchanged.

[0063] Example 1:

[0064] like Figure 1 As shown, this embodiment provides a laminated rubber spring 1, which has an overall axisymmetric disc-shaped rubber and metal composite structure. The laminated rubber spring 1 includes an upper metal skeleton 11, a first rubber layer 15, a first intermediate metal partition 13, a second rubber layer 16, a second intermediate metal partition 14, a third rubber layer 17, and a lower metal skeleton 12 arranged sequentially along the axial direction.

[0065] The upper metal frame 11 is located at the upper axial end of the laminated structure, and the lower metal frame 12 is located at the lower axial end of the laminated structure. The first intermediate metal partition 13 and the second intermediate metal partition 14 are axially spaced between the upper metal frame 11 and the lower metal frame 12. The central axes of the upper metal frame 11, the first intermediate metal partition 13, the second intermediate metal partition 14 and the lower metal frame 12 coincide, and the main pressure-bearing surfaces of each metal component are parallel to each other.

[0066] The two axial end faces of the first rubber layer 15 are vulcanized and bonded to the upper metal skeleton 11 and the first intermediate metal partition 13, respectively; the two axial end faces of the second rubber layer 16 are vulcanized and bonded to the first intermediate metal partition 13 and the second intermediate metal partition 14, respectively; the two axial end faces of the third rubber layer 17 are vulcanized and bonded to the second intermediate metal partition 14 and the lower metal skeleton 12, respectively. After vulcanization, the four metal components and the three rubber layers form an inseparable rubber-metal composite elastic component under normal use.

[0067] Both the upper metal frame 11 and the lower metal frame 12 are circular end bearing plates with a predetermined thickness, and their outer diameters are equal. The outer end face of the upper metal frame 11 can serve as a load input surface, and the outer end face of the lower metal frame 12 can serve as a support surface. When the laminated rubber spring 1 is installed in reverse, their force-bearing functions can be interchanged.

[0068] The outer diameters of the upper metal frame 11 and the lower metal frame 12 are both larger than the effective bearing diameters of the first rubber layer 15, the second rubber layer 16, and the third rubber layer 17. Therefore, the upper metal frame 11 and the lower metal frame 12 each have an annular outer edge that extends radially beyond the outer circumference of the three rubber layers, and this annular outer edge forms an annular mounting pressure-bearing part.

[0069] The annular mounting bearing section can mate with planar clamping components, support seats, or clamping components on the equipment. After the external structure applies a load to the annular mounting bearing section, the upper metal frame 11 or the lower metal frame 12 distributes the load to the central laminated region based on its own planar stiffness. The external mounting structure does not need to directly abut against the outer peripheral surface of the three rubber layers, thereby reducing the interference of the mounting components with the free shear area of ​​the rubber layers.

[0070] The first intermediate metal partition 13 and the second intermediate metal partition 14 are both annular plates with equal outer diameters, which are smaller than the outer diameters of the upper metal frame 11 and the lower metal frame 12. The outer diameters of the two intermediate metal partitions are also larger than the effective bearing diameter of the three rubber layers, so that the outer peripheral edges of the first intermediate metal partition 13 and the second intermediate metal partition 14 protrude radially from the outer peripheral surface of the three rubber layers.

[0071] The first intermediate metal partition 13 and the second intermediate metal partition 14 cover the main load-bearing section of the rubber layer and divide the overall rubber structure into three thinner compression units. Under normal load, the first intermediate metal partition 13 and the second intermediate metal partition 14 respectively restrict the radial free expansion of adjacent rubber layers, which is beneficial to improving the normal load-bearing capacity and axial dimensional stability of the laminated rubber spring 1.

[0072] The first rubber layer 15, the second rubber layer 16, and the third rubber layer 17 are all in the shape of thin discs, with equal effective load-bearing diameters and axially aligned outer surfaces. When using the same rubber material, the axial thickness of the three rubber layers can be equal, allowing them to achieve relatively similar compression and shear deformation capabilities. While satisfying the basic structure of this invention, the thickness of each rubber layer can also be adjusted according to the actual load distribution.

[0073] The effective load-bearing diameter of the rubber layer in this embodiment refers to the outer diameter of the circular region where the rubber layer is vulcanized and bonded to the adjacent metal component to bear axial loads. Figure 1 In the structure shown, the effective bearing diameter of the three rubber layers is consistent with the outer circumference diameter of the corresponding rubber layer.

[0074] Example 2:

[0075] This embodiment further explains the connection structure between the intermediate metal partition and the three rubber layers, based on Embodiment 1.

[0076] like Figure 1 As shown, the center of the first intermediate metal partition 13 and the second intermediate metal partition 14 are respectively provided with axial through holes 18. The two axial through holes 18 have the same diameter and are coaxially arranged along the central axis of the laminated rubber spring 1.

[0077] Each intermediate metal partition retains a continuous annular solid portion between its axial through-hole 18 and its outer peripheral edge. The axial through-hole 18 does not extend to the outer peripheral edge of the intermediate metal partition, thus not dividing the intermediate metal partition into multiple independent parts circumferentially. The annular solid portion constitutes the main pressure-bearing and restraining area of ​​the intermediate metal partition.

[0078] In the vulcanized state, the rubber materials of the first rubber layer 15, the second rubber layer 16, and the third rubber layer 17 enter the two axial through holes 18 and bond together in the central region corresponding to the axial through holes 18. The rubber materials located within and between the two axial through holes 18 together form the central rubber connection portion.

[0079] The upper axial portion of the central rubber connector is connected to the central region of the first rubber layer 15, the middle portion is connected to the central region of the second rubber layer 16, and the lower axial portion is connected to the central region of the third rubber layer 17. There are no mechanical assembly seams between the three rubber layers and the central rubber connector.

[0080] After vulcanization, the first rubber layer 15, the second rubber layer 16, the third rubber layer 17, and the central rubber connector together form an integral rubber body. The first intermediate metal partition 13 and the second intermediate metal partition 14 are respectively embedded in the integral rubber body, and the annular solid parts of the two intermediate metal partitions are located between two adjacent rubber layers.

[0081] The two axial surfaces of the first intermediate metal partition 13 are vulcanized and bonded to the first rubber layer 15 and the second rubber layer 16, respectively; the two axial surfaces of the second intermediate metal partition 14 are vulcanized and bonded to the second rubber layer 16 and the third rubber layer 17, respectively. The intermediate metal partitions can maintain the layered constraint effect on the three rubber layers without completely interrupting the rubber continuity in the central region of the laminated structure.

[0082] The diameter of the axial through hole 18 can be determined based on the required bearing area of ​​the intermediate metal partition, the required cross-sectional dimensions of the central rubber connection, and the flow conditions of the rubber compound during vulcanization. Sufficient radial distance should be maintained between the axial through hole 18 and the outer peripheral edge of the intermediate metal partition to form an annular solid part with appropriate width and bearing capacity.

[0083] The two axial through holes 18 are coaxially arranged so that the central rubber connection can extend continuously along the axial direction, avoiding significant bending when the central rubber connection passes through the first intermediate metal partition 13 and the second intermediate metal partition 14.

[0084] When the upper metal frame 11 and the lower metal frame 12 undergo horizontal relative displacement, the first rubber layer 15, the second rubber layer 16, and the third rubber layer 17 respectively undergo shear deformation, and the central rubber connector deforms together with the central region of the three rubber layers. The central rubber connector keeps the three disc-shaped rubber layers structurally continuous in the central region, which helps to reduce the interlayer relative misalignment that may occur when each rubber layer deforms completely independently.

[0085] As a typical size configuration, the effective load-bearing diameter of each of the three rubber layers is 80mm, the finished thickness of each single rubber layer is 3.0mm, and the total thickness of the three rubber layers is 9.0mm. The outer diameter of the upper metal frame 11 and the lower metal frame 12 is 115mm and the thickness is 8mm; the outer diameter of the first intermediate metal partition 13 and the second intermediate metal partition 14 is 84mm and the thickness is 2mm.

[0086] In other embodiments, the effective bearing diameter of the three rubber layers can be selected within the range of 78–82 mm, the thickness of a single rubber layer can be selected within the range of 2.9–3.1 mm, and the total thickness of the three rubber layers is correspondingly 8.7–9.3 mm. The outer diameter of the upper metal frame 11 and the lower metal frame 12 can be selected within the range of 110–120 mm, and the thickness can be selected within the range of 8–12 mm; the outer diameter of the first intermediate metal partition 13 and the second intermediate metal partition 14 is 84 mm, and the thickness can be selected within the range of 1.5–2.5 mm.

[0087] When the basic geometric relationship of the rubber layer is expressed by the effective bearing diameter D and the thickness h of a single rubber layer, the ratio of D to h can be controlled between 25 and 29, and the shape factor D / 4h of the circular rubber layer can be controlled between 6.2 and 7.3. With the above dimensional configuration, the single rubber layer can be kept in a thin disk shape, and the three rubber layers are constrained within three relatively thin axial intervals by the first intermediate metal partition 13 and the second intermediate metal partition 14.

[0088] The optional size range and typical dimensions of the main components of the laminated rubber spring in this embodiment are shown in Table 1.

[0089] Table 1. Dimensions of Laminated Rubber Springs

[0090]

[0091] The three rubber layers can be made of the same natural rubber material. As one feasible configuration, the natural rubber material has a hardness of 49 Shore A, a tensile strength of 25 MPa, an elongation at break of 623%, and a tensile set of 24%. In other embodiments, the natural rubber material can have a hardness of 45–55 Shore A, a tensile strength of not less than 20 MPa, an elongation at break of not less than 450%, and a tensile set of 35%.

[0092] The three rubber layers are preferably made of the same natural rubber material. The preferred performance range of the natural rubber material used and the measured values ​​of the test samples are shown in Table 2.

[0093] Table 2. Properties of Natural Rubber Materials and Measured Values ​​of Samples

[0094]

[0095] Within the aforementioned range, the effective bearing diameter of the rubber layer, the thickness of a single rubber layer, the thickness of the end metal frame, and the thickness of the intermediate metal partition can be selected in combination based on actual load-bearing requirements, installation space, and horizontal displacement requirements. For example, if radial installation compactness is a greater concern, a value can be selected at the lower end of the effective bearing diameter range of the rubber layer; if the stiffness of the end metal frame or the installation bearing area is a greater concern, a value can be selected at the upper end of the outer diameter and thickness range of the upper metal frame 11 and the lower metal frame 12. Regardless of the size combination used, the outer diameters of the upper metal frame 11 and the lower metal frame 12 should be greater than the outer diameters of the first intermediate metal partition 13 and the second intermediate metal partition 14, and the outer diameters of the two intermediate metal partitions should be greater than the effective bearing diameter of the rubber layer.

[0096] Example 3:

[0097] like Figure 2 As shown, this embodiment provides a two-part molding die for laminated rubber springs, including an upper die 21 and a lower die 22 arranged opposite to each other along the axial direction, and a two-part middle die 23 disposed between the upper die 21 and the lower die 22.

[0098] The upper mold 21 and the lower mold 22 are arranged opposite each other along the central axis of the mold and can move closer or further apart along the axial direction to achieve mold closing and mold opening. The two-part middle mold 23 includes two semi-annular middle modules, each of which has a planar profile that is semi-circular or approximately semi-circular.

[0099] The two semi-annular modules can approach and mate from their radially opposite sides, or they can separate from each other along opposite radial directions. Radial parting surfaces are formed at both circumferential ends of each semi-annular module. When the two semi-annular modules are in the mate position, their corresponding radial parting surfaces fit together, and the two semi-annular modules together form a complete annular mold.

[0100] When the two semi-annular modules are separated, the annular middle mold opens along the radial parting surface, allowing the internal space of the mold to open radially outward. The laminated assembly to be formed can be inserted into the mold without passing through the complete annular inner hole, and the laminated rubber spring 1 after vulcanization can also be removed from the radially open space after the two semi-annular modules are separated.

[0101] The upper mold 21, the lower mold 22, and the two-part middle mold 23 in a mating state together form a laminated molding cavity. The laminated molding cavity is used to accommodate the laminated rubber spring 1 to be molded, and to define the radial position and axial molding space of the laminated assembly during mold closing and vulcanization.

[0102] An upper pressing boss is provided on the side of the upper mold 21 facing the lower mold 22, and a lower pressing boss is provided on the side of the lower mold 22 facing the upper mold 21. The upper pressing boss and the lower pressing boss are arranged facing each other, and their facing end faces respectively form axial pressing surfaces.

[0103] When the mold is closed, the upper and lower pressing bosses extend into the inner circumference of the two-part intermediate mold 23 from both ends of the stacked forming cavity. The axial pressing surface of the upper mold 21 is opposite to the outer end face of the upper metal skeleton 11, and the axial pressing surface of the lower mold 22 is opposite to the outer end face of the lower metal skeleton 12.

[0104] When the upper mold 21 and the lower mold 22 approach each other, the two axial pressing surfaces transmit the mold closing pressure to the internal rubber blank through the upper metal frame 11 and the lower metal frame 12, respectively, so that the three layers of rubber blank are pressed between the adjacent metal components. The mold closing distance between the two axial pressing surfaces is used to limit the overall axial forming size of the laminated rubber spring 1.

[0105] After the two semi-annular modules are joined together, their inner circumferential sides together form a radially closed positioning surface along the circumference. The term "circumferentially closed" here means that the inner circumferential surfaces of the two semi-annular modules are connected to each other at the corresponding radial parting surfaces and form a complete circumferential positioning boundary around the laminated rubber spring 1 to be formed. It does not mean that the two semi-annular modules form a non-detachable connection.

[0106] The radial positioning surface includes, in sequence along the axial direction, an upper end frame positioning part, a first partition positioning part, a second partition positioning part, and a lower end frame positioning part. The upper end frame positioning part is used for radial positioning of the upper metal frame 11, and the lower end frame positioning part is used for radial positioning of the lower metal frame 12; the first partition positioning part and the second partition positioning part are used for radial positioning of the first intermediate metal partition 13 and the second intermediate metal partition 14, respectively.

[0107] The upper and lower end frame positioning portions have a first radial positioning dimension that matches the outer diameter of the upper metal frame 11 and the lower metal frame 12. The first and second partition positioning portions have a second radial positioning dimension that matches the outer diameter of the first intermediate metal partition 13 and the second intermediate metal partition 14. Since the outer diameter of the end metal frame is larger than the outer diameter of the two intermediate metal partitions, the first radial positioning dimension is larger than the second radial positioning dimension.

[0108] Each positioning part uses the central axis of the two-part middle mold 23 as the processing and positioning reference, so that the upper metal frame 11, the first intermediate metal partition 13, the second intermediate metal partition 14 and the lower metal frame 12 obtain a common central position reference during the mold assembly process.

[0109] In this embodiment, the radial positioning surface adopts a stepped positioning surface. On the inner circumference of each semi-annular module, an upper end skeleton positioning segment, a first partition positioning segment, a second partition positioning segment, and a lower end skeleton positioning segment are sequentially formed along the axial direction. Adjacent positioning segments with different radial positioning dimensions are connected by axially extending support and limiting portions.

[0110] Each positioning segment extends primarily along the axial direction and forms a clearance fit or a detachable contact fit with the outer circumferential surface of the corresponding metal component to restrict radial movement of the corresponding metal component. The axial support and limiting part is opposite to the outer edge of the axial end face of the corresponding metal component and is used to maintain the initial axial position of the metal component before the rubber blank is inserted and the upper mold 21 is closed.

[0111] In another embodiment, the first partition positioning part and the second partition positioning part each include an annular positioning groove. Each annular positioning groove is formed by the mating of two semi-annular grooves respectively disposed on the two semi-annular modules.

[0112] The outer peripheral edge of the first intermediate metal partition 13 extends into an annular positioning groove, and the outer peripheral edge of the second intermediate metal partition 14 extends into another annular positioning groove. The bottom of the annular positioning groove is used to restrict the radial movement of the intermediate metal partition, and the sidewalls of the groove located on both sides of the bottom of the groove are used to restrict the intermediate metal partition from excessive axial movement or tilting.

[0113] When the two semi-annular modules are in a separated state, each annular positioning groove is divided into two semi-annular grooves along the circumference. The outer peripheral edge of the middle metal partition can leave the corresponding semi-annular groove radially and will not be blocked by the axial direction of the complete annular groove.

[0114] The outer periphery of the upper mold 21 and the lower mold 22 are respectively provided with mold closing positioning holes that are opposite each other along the axial direction, and positioning pins 24 are inserted into the oppositely arranged mold closing positioning holes. The positioning pins 24 can be fixed to the lower mold 22 and slide in engagement with the mold closing positioning holes on the upper mold 21, or they can be fixed to the upper mold 21 and slide in engagement with the mold closing positioning holes on the lower mold 22.

[0115] When the upper mold 21 and the lower mold 22 move relative to each other along the axial direction, the positioning pin 24 engages with the mold closing positioning hole to guide the relative movement of the upper mold 21 and the lower mold 22 and restrict the radial misalignment between them, so that the upper pressing boss, the lower pressing boss and the two-lobed middle mold 23 remain coaxial.

[0116] The upper mold 21 and the lower mold 22 are also provided with middle mold limiting surfaces facing the two-lobed middle mold 23. The two middle mold limiting surfaces are arranged opposite each other along the axial direction, and the two-lobed middle mold 23 is located between the two middle mold limiting surfaces when it is in the closed state.

[0117] After the upper mold 21 and lower mold 22 are fully closed, the two middle mold limiting surfaces together axially limit the two-part middle mold 23, preventing it from deviating axially from its designed position under the action of mold closing pressure. The middle mold limiting surfaces cooperate with the locating pins 24 to keep the radial locating surfaces in the axial position corresponding to the metal components of the laminated rubber spring 1.

[0118] Example 4:

[0119] This embodiment uses the two-part molding die described in Embodiment 3 to prepare the laminated rubber spring 1 described in Embodiment 1. The preparation process is as follows: Figure 5 As shown, it includes the following steps.

[0120] Step S1 involves preparing and quantitatively cutting rubber sheets.

[0121] The mixed natural rubber compound is calendered, die-cut, or cut into first rubber sheets, second rubber sheets, and third rubber sheets corresponding to the first rubber layer 15, the second rubber layer 16, and the third rubber layer 17, respectively.

[0122] The target thickness of each rubber sheet is 3.0 mm, and the thickness can vary within the range of 2.9 to 3.1 mm. The thickness error of a single sheet is preferably no more than ±0.1 mm. The theoretical rubber quantity is determined according to the design volume and rubber density of a single rubber layer, and each rubber sheet is weighed or quantitatively measured by equal volume to ensure that the rubber quantity error of a single layer is preferably no more than ±3% of the theoretical rubber quantity.

[0123] Step S2: Perform surface treatment on the metal components.

[0124] The upper metal frame 11, lower metal frame 12, first intermediate metal partition 13, and second intermediate metal partition 14 are degreased to remove oil and impurities from the surfaces to be bonded. Depending on the metal material and bonding process, the surfaces to be bonded are roughened or sandblasted to create a surface condition suitable for adhesive adhesion.

[0125] After roughening or sandblasting, remove dust and residue from the surface of the metal components. Apply an adhesive suitable for rubber-metal vulcanization bonding evenly to the surfaces to be bonded and allow it to dry according to the adhesive process requirements. The walls of the two axial through holes 18 and their adjacent areas should be kept clean to prevent oil or dust from hindering the bonding of the adhesive in the central area.

[0126] Step S3: Perform layered molding.

[0127] Before assembly, the upper mold 21 and the lower mold 22 are separated axially, and the two semi-annular modules of the two-part middle mold 23 are separated radially. Using the lower mold 22 as the assembly reference, the lower metal skeleton 12 is placed on the lower pressing boss of the lower mold 22.

[0128] Subsequently, the third rubber sheet, the second intermediate metal partition 14, the second rubber sheet, the first intermediate metal partition 13, the first rubber sheet, and the upper metal frame 11 are stacked in sequence. During the stacking process, the axial through holes 18 of the first intermediate metal partition 13 and the second intermediate metal partition 14 are kept coaxial or substantially coaxial, and each rubber sheet covers the corresponding area to be bonded.

[0129] Step S4: Perform the two-part middle mold alignment and radial positioning.

[0130] After the initial stacking is completed, the two semi-circular modules are brought closer together from their radially opposite sides and joined to form a two-lobed middle mold 23. The upper end skeleton positioning part and the lower end skeleton positioning part surround the outer peripheral edges of the upper metal skeleton 11 and the lower metal skeleton 12, respectively, and the first partition positioning part and the second partition positioning part surround the outer peripheral edges of the first intermediate metal partition 13 and the second intermediate metal partition 14, respectively.

[0131] The upper metal frame 11, the first intermediate metal partition 13, the second intermediate metal partition 14, and the lower metal frame 12 are thus positioned using the central axis of the two-lobed intermediate mold 23 as a common positioning reference. When a stepped positioning surface is used, the axial support and limiting part maintains the initial axial position of the two intermediate metal partitions; when a groove positioning structure is used, the outer peripheral edges of the two intermediate metal partitions respectively enter the corresponding annular positioning grooves.

[0132] Step S5 involves axial mold closing, pre-pressurization and venting, and vulcanization molding.

[0133] The upper mold 21 moves axially toward the lower mold 22. The locating pin 24 engages with the corresponding mold closing locating hole to guide the relative movement of the upper mold 21 and the lower mold 22. The axial pressing surfaces of the upper pressing boss and the lower pressing boss contact the outer end faces of the upper metal frame 11 and the lower metal frame 12, respectively.

[0134] As the upper mold 21 and lower mold 22 continue to close, the three rubber sheets are compressed between adjacent metal components and gradually adhere to the surfaces to be bonded. The thickness and amount of rubber sheets, the mold closing distance between the two axial pressing surfaces, the initial support position of the intermediate metal partition, and the axial dimensions of the mold cavity jointly control the molding space of each layer of rubber.

[0135] After mold closing, pre-compression is applied at 2–4 MPa for 1–10 minutes. During pre-compression, the rubber compound gradually fills the interlayer space and adheres to the metal surface. Air in the interface and central area is discharged through the rubber compound flow path and the mold parting position. Some rubber compound enters the two axial through holes 18, causing adjacent rubber sheets to contact each other in the central area.

[0136] After pre-compression, vulcanization is carried out at 145–155℃ and 6–10MPa for 150–180 min. During vulcanization, the first rubber layer 15, the second rubber layer 16, and the third rubber layer 17 form vulcanization bonding interfaces with adjacent metal components, and the rubber material in the two axial through holes 18 cross-links to form a continuous central rubber connection.

[0137] Step S6 involves mold opening, removal, trimming, and inspection.

[0138] After the set vulcanization time is reached, the mold closing pressure is released, causing the upper mold 21 and lower mold 22 to separate axially. Once the mold and product meet the demolding requirements, the two semi-annular middle modules of the two-part middle mold 23 are separated radially from each other.

[0139] After the two semi-circular modules are separated, the laminated rubber spring 1 can be removed from the radial open space without having the upper metal frame 11 and lower metal frame 12 with larger outer diameters pass through the smaller positioning area that matches the outer diameter of the intermediate metal partition along the axial direction.

[0140] Trim the removed laminated rubber spring 1, remove the rubber edges formed on the outer periphery of the product and the mold parting position, and check the appearance of the metal components, the outer periphery of the three rubber layers, the visible bonding interface and the overall dimensions of the product.

[0141] Example 5:

[0142] This embodiment further illustrates the combination of process parameters within the scope of the claims. The rubber sheet thickness, single-layer rubber content, pre-compression conditions, and vulcanization conditions are not isolated control parameters. The rubber sheet thickness affects the initial axial dimensions of each layer; the single-layer rubber content affects whether the rubber compound can completely fill the interlayer space and the amount of overflow; the pre-compression pressure and time affect the bonding, flow, and interfacial venting of the rubber compound; and the vulcanization temperature, time, and pressure affect the degree of rubber crosslinking and the bonding state between the metal and the rubber.

[0143] As the first process combination, the rubber sheet thickness is 2.9 mm, the pre-compression pressure is 2 MPa, the pre-compression time is 8–10 min, the vulcanization temperature is 145℃, the vulcanization pressure is 6–8 MPa, and the vulcanization time is 170–180 min. This combination uses a relatively low vulcanization temperature and ensures complete cross-linking of the rubber material by extending the vulcanization time.

[0144] As the second process combination, the rubber sheet thickness is 3.0 mm, the single-layer rubber content error is controlled within ±3%, the pre-compression pressure is 3 MPa, the pre-compression time is 5 min, the vulcanization temperature is 150℃, the vulcanization pressure is 8 MPa, and the vulcanization time is 165 min. This combination serves as a typical process condition and is applicable to the laminated rubber spring 1 of the typical dimensions described in Example 1.

[0145] As the third process combination, the rubber sheet thickness is 3.1 mm, the pre-compression pressure is 4 MPa, the pre-compression time is 1–3 min, the vulcanization temperature is 155℃, the vulcanization pressure is 10 MPa, and the vulcanization time is 150 min. When using this combination, the amount of overflow should be controlled in conjunction with the mold cavity volume and the amount of rubber per layer to avoid excessive flow resistance during mold closing when the rubber sheet thickness is close to the upper limit.

[0146] The above-described process combinations all fall within the process window disclosed in this invention. In actual production, specific parameters should be confirmed based on the vulcanization characteristics of the selected natural rubber system, the heat capacity of the metal components, the heat transfer conditions of the mold, and the requirements for the adhesive used.

[0147] When using an annular positioning groove to position the intermediate metal partition, the fitting clearance between the annular positioning groove and the outer peripheral edge of the intermediate metal partition should be checked to ensure that the intermediate metal partition can be stably positioned without hindering radial demolding after vulcanization.

[0148] When using stepped positioning surfaces, the corresponding positions of the axial support limiting part and the outer edge of the intermediate metal partition should be checked to avoid the axial support limiting part extending excessively into the main bonding area between the rubber and the metal.

[0149] To control batch consistency, the thickness and quality of each rubber sheet can be recorded before molding, the integrity of the surface to be bonded can be checked after metal surface treatment, the radial parting surface of the two semi-annular middle modules can be checked after the two-part middle mold 23 is closed, and the upper mold 21 and lower mold 22 can be checked to see if they have reached the set mold closing position during the pre-pressing stage.

[0150] A laminated rubber spring prototype was fabricated using the typical dimensions of Example 1 and the preparation method of Example 4. The effective bearing diameter of the rubber layer of the prototype is approximately 80 mm, the thickness of a single rubber layer is approximately 3.0 mm, the outer diameter of the upper metal frame 11 and the lower metal frame 12 is approximately 115 mm, and the thickness is approximately 8 mm. The outer diameter of the first intermediate metal partition 13 and the second intermediate metal partition 14 is approximately 84 mm, and the thickness is approximately 2 mm.

[0151] The finished product is first inspected for appearance and dimensions. The upper metal frame 11, the first intermediate metal partition 13, the second intermediate metal partition 14 and the lower metal frame 12 of the sample are kept coaxial, and the outer peripheral surfaces of the first rubber layer 15, the second rubber layer 16 and the third rubber layer 17 are basically aligned along the axial direction.

[0152] A multi-stage cyclic normal loading test was conducted on the sample. During the test, a load was applied along the axial direction of the laminated rubber spring 1, and the normal load was gradually increased to 97.0 kN. Figure 3 The normal load-displacement curve of the sample is shown.

[0153] After loading was completed, the sample was observed. No visible cracks were found in the first rubber layer 15, the second rubber layer 16, and the third rubber layer 17. No visible interface debonding was found between the upper metal skeleton 11, the lower metal skeleton 12, the first intermediate metal partition 13, the second intermediate metal partition 14, and the adjacent rubber layers.

[0154] Based on the circular area corresponding to an effective bearing diameter of 80 mm, the average normal compressive stress corresponding to a normal load of 97.0 kN is approximately 19.3 MPa. According to the axial displacement variation corresponding to the load range of 62.0 kN to 97.0 kN in the third loading cycle, the normal static stiffness of the sample is in the range of 77000–96000 kN / m.

[0155] The normal load-displacement curve exhibits nonlinearity under compression in rubber materials and hysteresis during loading and unloading. Therefore, the calculation of normal static stiffness uses a stable loading cycle and a defined load range, and does not use the local slope near zero load as the normal static stiffness.

[0156] Based on the normal load test, a horizontal shear static stiffness test was conducted on the sample. During the test, one end of the laminated rubber spring 1 was fixed, and under the condition of maintaining a specified normal load, the other end was moved horizontally back and forth in a direction perpendicular to the central axis, and the horizontal shear force and horizontal displacement were recorded. Figure 4 The corresponding horizontal shear force-displacement curves are shown.

[0157] To minimize the impact of initial clamping and rubber material adjustment on the calculation results, data from the third loading cycle were used. When the horizontal displacement of the moving end is approximately +4.98 mm and -5.00 mm, the corresponding horizontal shear forces are approximately +1163.8 N and -1115.5 N, respectively.

[0158] The horizontal equivalent shear stiffness of the sample was calculated by dividing the difference in shear force between the positive and negative displacement endpoints by the difference in displacement, i.e., dividing 2279.3 N by 9.98 mm. This yields an estimated horizontal equivalent shear stiffness of approximately 228.4 N / mm, which is equivalent to 228.4 kN / m. Based on test records from different calculation points or samples of the same structure, the horizontal shear stiffness falls within the range of 220–240 kN / m.

[0159] After the sample underwent a ±5mm horizontal reciprocating load, no obvious cracking or tearing occurred in the three rubber layers, and no obvious interface debonding occurred between the metal component and the adjacent rubber layers. Based on the actual measured normal static stiffness and horizontal shear stiffness of the corresponding sample, the ratio of normal stiffness to horizontal shear stiffness was within the range of 350 to 400.

[0160] The above test results show that the laminated rubber spring 1 can maintain a low horizontal shear stiffness while bearing a large normal load. The first intermediate metal partition 13 and the second intermediate metal partition 14 form a layered constraint on the three rubber layers, and the three rubber layers share the horizontal displacement. The central rubber connection ensures that the three rubber layers maintain structural continuity in the central region.

[0161] After the laminated rubber spring 1 has been vulcanized and finished, it can be inspected in sequence for appearance, dimensions, normal load capacity and horizontal shear performance.

[0162] During visual inspection, check the visible outer edges of the upper metal frame 11, lower metal frame 12, first intermediate metal partition 13, and second intermediate metal partition 14 to confirm that there is no significant deformation that would affect installation or loading; check the outer surfaces of the first rubber layer 15, second rubber layer 16, and third rubber layer 17 to confirm that there is no obvious lack of adhesive, through cracks, or abnormal inclusions; check the visible metal-rubber interface to confirm that there is no obvious lifting or detachment.

[0163] During dimensional inspection, the outer diameters of the upper metal frame 11 and the lower metal frame 12, the total height of the finished product, and the measurable thickness of each rubber layer are measured, and the corresponding thicknesses are compared along different circumferential positions. It can also be checked whether the outer peripheral edges of the first intermediate metal partition 13 and the second intermediate metal partition 14 protrude radially from the outer peripheral surface of the three rubber layers.

[0164] For the molding die, you can check whether the radial parting surfaces of the two semi-circular modules fit together, whether the upper and lower skeleton positioning parts are coaxial, whether the first and second partition positioning parts are coaxial, and whether there is an abnormal gap between the positioning pin 24 and the mold closing positioning hole.

[0165] When the finished product has a large difference in the thickness of the rubber layer along the circumference, the outer diameter tolerance of the metal components, the radial dimensions of each positioning part of the two-part middle mold 23, the bonding state of the parting surface of the two semi-annular middle modules, the initial axial position of the middle metal partition, and the thickness and amount of rubber sheet can be checked in sequence.

[0166] When the horizontal shear stiffness of the finished product is discrete but the appearance and dimensions are basically normal, the batch of rubber compound, vulcanization temperature, vulcanization time, metal surface treatment status and adhesive drying status can be further checked to determine whether the performance difference comes from the rubber blank, component positioning, mold closing process or vulcanization process.

[0167] The laminated rubber spring 1 can be installed between equipment and foundation that needs to withstand normal loads and allow for horizontal fretting or reciprocating displacement. For example, it can serve as a flexible load-bearing support for mechanical equipment, a support component for vibration test benches, an elastic support in low-resistance guide systems to accommodate installation deviations, or a flexible connector between two load-bearing components.

[0168] During installation, the external structure preferably acts on the annular mounting pressure-bearing parts of the upper metal frame 11 and the lower metal frame 12, and sharp edges should be avoided from directly pressing the free outer periphery of the three rubber layers. The horizontal displacement direction of the laminated rubber spring 1 can be any direction perpendicular to the central axis. The specific number and arrangement of installations can be determined according to the normal load, horizontal displacement range and stability requirements of the external equipment.

[0169] The above embodiments illustrate the laminated rubber spring 1, the two-part molding die, and the preparation method. Without departing from the basic concept of this invention, those skilled in the art can adjust the thickness of the end metal frame, the thickness of the middle metal partition, the dimensions of the rubber layer, the diameter of the axial through hole 18, the die positioning structure, and the specific vulcanization parameters. All such adjustments should be considered reasonable modifications or substitutions to the content disclosed in this invention.

[0170] The above examples illustrate the present invention only to aid in understanding it and are not intended to limit the scope of the invention. Those skilled in the art can make various simple deductions, modifications, or substitutions based on the principles of this invention.

Claims

1. A laminated rubber spring (1), characterized in that, It includes an upper metal frame (11), a first rubber layer (15), a first intermediate metal partition (13), a second rubber layer (16), a second intermediate metal partition (14), a third rubber layer (17), and a lower metal frame (12) arranged sequentially along the axial direction. The upper metal frame (11), the first intermediate metal partition (13), the second intermediate metal partition (14) and the lower metal frame (12) are coaxially arranged; The first rubber layer (15) is vulcanized and bonded to the upper metal skeleton (11) and the first intermediate metal partition (13) respectively; the second rubber layer (16) is vulcanized and bonded to the first intermediate metal partition (13) and the second intermediate metal partition (14) respectively; and the third rubber layer (17) is vulcanized and bonded to the second intermediate metal partition (14) and the lower metal skeleton (12) respectively. The first intermediate metal partition (13) and the second intermediate metal partition (14) are both annular plates with axial through holes (18). The two axial through holes (18) are coaxially arranged. The rubber materials of the first rubber layer (15), the second rubber layer (16) and the third rubber layer (17) extend into the two axial through holes (18) and are connected to each other, so that the three rubber layers form an integral rubber body. The outer diameters of the upper metal frame (11) and the lower metal frame (12) are both greater than the outer diameters of the first intermediate metal partition (13) and the second intermediate metal partition (14), and the outer diameters of the first intermediate metal partition (13) and the second intermediate metal partition (14) are both greater than the effective bearing diameter of the three rubber layers.

2. The laminated rubber spring (1) according to claim 1, characterized in that, The upper metal frame (11) and the lower metal frame (12) are both circular end bearing plates, and the portions of the two that extend radially beyond the outer periphery of the three rubber layers respectively form annular mounting bearing parts; The outer diameters of the first intermediate metal partition (13) and the second intermediate metal partition (14) are equal and smaller than the outer diameters of the upper metal skeleton (11) and the lower metal skeleton (12), and their outer peripheral edges protrude radially from the outer peripheral surface of the three rubber layers; The effective bearing diameters of the first rubber layer (15), the second rubber layer (16) and the third rubber layer (17) are equal and their outer peripheral surfaces are aligned along the axial direction. The main pressure-bearing surfaces of the upper metal frame (11), the first intermediate metal partition (13), the second intermediate metal partition (14) and the lower metal frame (12) are parallel to each other.

3. The laminated rubber spring (1) according to claim 1, characterized in that, The two axial through holes (18) have the same diameter. The rubber material located inside and between the two axial through holes (18) forms a central rubber connection part. The central rubber connection part is connected to the central area of ​​the first rubber layer (15), the second rubber layer (16) and the third rubber layer (17) respectively. The first intermediate metal partition (13) and the second intermediate metal partition (14) respectively form a continuous annular solid part between the corresponding axial through hole (18) and its outer peripheral edge, and the two intermediate metal partitions are respectively embedded in the integral rubber body.

4. The laminated rubber spring (1) according to claim 1, characterized in that, The effective bearing diameter of the first rubber layer (15), the second rubber layer (16) and the third rubber layer (17) is 78-82 mm, the thickness of a single rubber layer is 2.9-3.1 mm, and the total thickness of the three rubber layers is 8.7-9.3 mm. The outer diameter of the upper metal frame (11) and the lower metal frame (12) are both 110-120 mm and the thickness is both 8-12 mm; the outer diameter of the first intermediate metal partition (13) and the second intermediate metal partition (14) are both 84 mm and the thickness is both 1.5-2.5 mm. The ratio of the effective bearing diameter to the thickness of the single rubber layer is 25 to 29, and the shape factor of the single rubber layer is 6.2 to 7.

3. The shape factor is determined according to the ratio of the effective bearing diameter to four times the thickness of the single rubber layer. All three rubber layers are made of natural rubber material, which has a hardness of 45-55 Shore A, a tensile strength of not less than 20 MPa, an elongation at break of not less than 450%, and a permanent deformation at break of not more than 35%.

5. A two-part molding die for laminated rubber springs, characterized in that, It includes an upper mold (21) and a lower mold (22) arranged opposite each other along the axial direction, and a two-part middle mold (23) disposed between the upper mold (21) and the lower mold (22); The two-lobed middle mold (23) includes two semi-annular middle modules that can be separated from each other radially. The two semi-annular middle modules are joined together to form an annular middle mold. The inner circumferential side of the annular middle mold forms a radially closed positioning surface along the circumference. The upper mold (21), the lower mold (22), and the two-lobed middle mold (23) in the mating state together form a lamination forming cavity for accommodating the laminated rubber spring (1) to be formed. The upper mold (21) and the lower mold (22) are respectively provided with axially opposed pressing surfaces on the side facing the lamination forming cavity. The radial positioning surface includes an upper end skeleton positioning part, a first partition positioning part, a second partition positioning part and a lower end skeleton positioning part distributed sequentially along the axial direction. The upper end skeleton positioning part and the lower end skeleton positioning part have a first radial positioning dimension that is adapted to the outer diameter of the upper metal skeleton (11) and the lower metal skeleton (12) of the laminated rubber spring (1) to be formed. The first partition positioning part and the second partition positioning part have a second radial positioning dimension that is adapted to the outer diameter of the first intermediate metal partition (13) and the second intermediate metal partition (14) of the laminated rubber spring (1) to be formed. The first radial positioning dimension is larger than the second radial positioning dimension.

6. The two-part molding die according to claim 5, characterized in that, Each of the semi-circular inner modules has a radial parting surface at both circumferential ends. The corresponding radial parting surfaces of the two semi-circular inner modules in the mating state are in contact with each other. The plane where the radial parting surface is located passes through the central axis of the two-lobed inner mold (23). Each of the semi-circular modules has an upper end skeleton positioning section, a first partition plate positioning section, a second partition plate positioning section and a lower end skeleton positioning section arranged sequentially along the axial direction on its radial positioning surface. Adjacent positioning sections with different radial positioning dimensions are connected by an axially extending support and limiting part. Each positioning segment forms a radially extending contact limiting part, which forms a clearance fit or a detachable contact fit with the outer circumferential surface of the corresponding metal component, and the axially supporting limiting part is disposed opposite to the outer edge of the axial end face of the corresponding metal component.

7. The two-part molding die according to claim 5, characterized in that, The first partition positioning part and the second partition positioning part each include an annular positioning groove. Each annular positioning groove is formed by the engagement of two semi-annular grooves respectively disposed on the two semi-annular modules. The annular positioning groove has a groove bottom and groove sidewalls located on both sides of the groove bottom in the axial direction. The groove bottom is used to restrict the corresponding first intermediate metal partition (13) or second intermediate metal partition (14) from moving radially. The two groove sidewalls are used to restrict the corresponding first intermediate metal partition (13) or second intermediate metal partition (14) from moving axially or tilting. The upper mold (21) has an upper pressing boss on the side facing the lower mold (22), and the lower mold (22) has a lower pressing boss on the side facing the upper mold (21). The end faces of the upper pressing boss and the lower pressing boss facing each other constitute the axial pressing surface. The outer periphery of the upper mold (21) and the lower mold (22) are respectively provided with mold closing positioning holes that are opposite to each other along the axial direction, and positioning pins (24) are inserted into the oppositely arranged mold closing positioning holes. The upper mold (21) and the lower mold (22) are respectively provided with a middle mold limiting surface facing the two-lobed middle mold (23), and the two-lobed middle mold (23) in the mold closing state is axially limited between the two middle mold limiting surfaces.

8. A method for preparing a laminated rubber spring (1), characterized in that, The steps include the following: S1, the compounded rubber is made into a first rubber sheet, a second rubber sheet and a third rubber sheet corresponding to the first rubber layer (15), the second rubber layer (16) and the third rubber layer (17) respectively, and each rubber sheet is quantitatively cut according to the design volume of a single rubber layer; S2, the upper metal frame (11), the lower metal frame (12), the first intermediate metal partition (13) and the second intermediate metal partition (14) are surface treated, and rubber and metal adhesive are applied to the surfaces to be bonded and dried. The first intermediate metal partition (13) and the second intermediate metal partition (14) are both annular plates with axial through holes (18). S3, when the molding die including the upper mold (21), the lower mold (22) and the two semi-circular middle modules are in the open state, the lower metal skeleton (12), the third rubber sheet, the second intermediate metal partition (14), the second rubber sheet, the first intermediate metal partition (13), the first rubber sheet and the upper metal skeleton (11) are stacked on the lower mold (22) in the following order; S4, the two semi-annular modules are joined together from both sides of the radial direction to form a two-lobed middle mold (23). The circumferential closed radial positioning surface formed after the two semi-annular modules are joined together is used to position the outer peripheral edges of the upper metal frame (11), the lower metal frame (12), the first intermediate metal partition (13), and the second intermediate metal partition (14), respectively. The first radial positioning dimension used to position the upper metal frame (11) and the lower metal frame (12) is greater than the second radial positioning dimension used to position the first intermediate metal partition (13) and the second intermediate metal partition (14), so that each metal component takes the central axis of the two-lobed middle mold (23) as a common positioning reference. S5, the upper mold (21) and the lower mold (22) are closed along the axial direction, and the two axial pressing surfaces are pressed together on the upper metal skeleton (11) and the lower metal skeleton (12) in turn, and pre-pressing and vulcanizing are performed in sequence, so that the first rubber layer (15), the second rubber layer (16) and the third rubber layer (17) are respectively vulcanized and bonded to the adjacent metal components, and the rubber material enters the two axial through holes (18) to connect the three rubber layers into one; S6. After vulcanization, the upper mold (21) and the lower mold (22) are separated axially, and the two semi-annular modules are separated radially. The molded laminated rubber spring (1) is then removed, trimmed, and inspected.

9. The preparation method according to claim 8, characterized in that, In step S1, the thickness of each rubber sheet is 2.9 to 3.1 mm, the thickness error does not exceed ±0.1 mm, and the amount of rubber corresponding to a single rubber layer does not exceed ±3% of the theoretical amount of rubber. The surface treatment in step S2 includes degreasing and roughening or sandblasting. After the surface treatment is completed, the surface of the metal component is cleaned, and then the rubber and metal adhesive is applied and dried. In step S4, the initial axial positions of the first intermediate metal partition (13) and the second intermediate metal partition (14) are maintained by the axial support limiting part or the annular positioning groove provided on the radial positioning surface, and the axial spacing between adjacent metal components is determined by the thickness and amount of each rubber sheet and the mold closing distance between the two axial pressing surfaces.

10. The preparation method according to claim 8, characterized in that, In step S5, the pre-compression pressure is 2-4 MPa, the pre-compression time is 1-10 min, the vulcanization temperature is 145-155℃, the vulcanization time is 150-180 min, and the vulcanization pressure is 6-10 MPa. In step S5, a portion of the rubber material is axially connected through the two axial through holes (18) and forms a continuous central rubber connection after vulcanization. In step S6, after the upper mold (21) and the lower mold (22) separate axially, the two semi-annular middle modules separate radially, so that the two-lobed middle mold (23) opens from the outer periphery of the laminated rubber spring (1).

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