Belleville spring, belleville spring set and electro-hydraulic composite tensioning mechanism

Abstract

The invention discloses a belleville spring, a belleville spring set and an electro-hydraulic composite tensioning mechanism, and relates to the technical field of tensioning force adjusting.The belleville spring comprises a belleville spring body, and the wall thickness of the belleville spring body is gradually decreased from the center to the direction away from the center; according to the variable cross-section design structure of the belleville spring, the bearing capacity range of the belleville spring is increased, stress can be evenly and progressively decreased from the center to the position away from the center, the problem that local stress is too high is solved, the fatigue failure risk of the belleville spring is reduced, and the service life is prolonged.

Description

Technical Field

[0001] The present invention relates to the technical field of tensioning force adjustment, and in particular to a butterfly spring, a butterfly spring group and an electro-hydraulic composite tensioning mechanism. Background Art

[0002] In traditional track tensioning systems, the tensioning force is adjusted by direct hydraulic drive or by directly driving the tensioning wheel through a drive motor to achieve reciprocating movement. However, there are problems such as a narrow preload adjustment range (80-120kN), slow response speed (200ms), high energy consumption, excessive tension on the tensioning wheel, and reduced service life. It cannot adapt to the dynamic load requirements under complex working conditions, resulting in a low fatigue life of the track plate.

[0003] Therefore, it is necessary to develop and design butterfly springs, butterfly spring groups and electro-hydraulic composite tensioning mechanisms. Improving the adjustment range of the preload force and improving the response speed are technical problems that technical personnel in this field urgently need to solve. Summary of the Invention

[0004] In order to solve the above problems, the present invention provides a butterfly spring to increase the adjustment range of the preload force and improve the response speed.

[0005] To achieve the above object, the present invention provides the following solutions:

[0006] A butterfly spring comprises a butterfly spring body, wherein the wall thickness of the butterfly spring body gradually decreases from the center to a direction away from the center.

[0007] Preferably, the butterfly spring body is an annular structure with an isosceles trapezoidal cross-section.

[0008] Preferably, the inner diameter of the butterfly spring body is 40mm to 60mm, the outer diameter of the butterfly spring body is 80mm to 100mm, the thickness of the butterfly spring body near the center is 3mm to 5mm, and the thickness of the butterfly spring body away from the center is 1.5mm to 2.5mm.

[0009] Preferably, the material of the butterfly spring body is a nickel-based alloy, a diamond-like coating is deposited on the surface, the friction coefficient is ≤0.15, and the linear expansion coefficient is ≤13×10-6 / °C.

[0010] The present invention also discloses a butterfly spring assembly, which uses the butterfly spring described above and includes two butterfly spring bodies with outer rings buckled together.

[0011] The present invention also discloses an electro-hydraulic composite tensioning mechanism, which uses the butterfly spring group described above, including at least two butterfly spring groups connected end to end, a tensioning wheel connecting piece arranged at one end of the butterfly spring group connected end to end, and a driving device arranged at the other end of the butterfly spring group connected end to end to realize the extension and retraction of the butterfly spring group.

[0012] Preferably, a buffer is provided between the driving device and the butterfly spring assembly located near one end of the driving device, and the buffer is connected to the accumulator.

[0013] Preferably, a tension pressure sensor for testing tension pressure is provided between the buffer and the driving device, and the tension pressure sensor is communicatively connected with a controller, and the controller is used to control the opening and closing of the driving device.

[0014] Preferably, the driving device includes a driving motor, a screw connected to the output end of the driving motor, and a nut threadedly connected to the screw and capable of reciprocating along the axial direction of the screw, and the nut is connected to the tension and pressure sensor.

[0015] Preferably, the driving device is an electric push rod, and the electric push rod is connected to the tension and pressure sensor.

[0016] Compared with the prior art, the present invention has achieved the following technical effects:

[0017] The variable cross-section design structure of the butterfly spring increases the range of the butterfly spring's own bearing capacity, and can make the stress decrease evenly from the center to away from the center, avoiding the problem of local excessive stress, thereby reducing the risk of fatigue failure of the butterfly spring and extending its service life. The total deformation stroke can be linearly increased through the outer ring buckle combination to meet the scenario requiring large displacement compensation. By connecting at least two butterfly spring groups in series, the adjustment range of the butterfly spring assembly can be greatly improved compared to linear springs of the same size. When the tensioning force needs to be adjusted, the tensioning force can be adjusted by driving the butterfly spring assembly to extend and retract through the driving device. When the driving device drives the butterfly spring to move toward the direction close to the tensioning wheel connecting piece, the tensioning force can be reduced. When the driving device drives the butterfly spring to move away from the tensioning wheel connecting piece, the tensioning force can be increased. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0019] Attachment Figure 1This is a schematic diagram of the overall structure of the butterfly spring disclosed in the present invention;

[0020] Attachment Figure 2 This is a schematic structural diagram of the electro-hydraulic composite tensioning mechanism disclosed in the present invention;

[0021] Among them, 1. butterfly spring body; 2. drive motor; 3. controller; 4. accumulator; 5. buffer; 6. tensioner arm; 7. tensioner connector; 8. butterfly spring assembly; 9. tension and pressure sensor; 10. screw. DETAILED DESCRIPTION

[0022] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0023] The purpose of the present invention is to provide a butterfly spring, a butterfly spring group and an electro-hydraulic composite tensioning mechanism, which can increase the adjustment range of the preload force and improve the response speed.

[0024] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0025] refer to Figure 1 The butterfly spring disclosed in the embodiment of the present invention includes at least a butterfly spring body 1. The wall thickness of the butterfly spring body 1 gradually decreases from the center to the direction away from the center. The variable cross-section design structure of the butterfly spring increases the range of the butterfly spring body 1's own bearing capacity and can make the stress decrease evenly from the center to the direction away from the center, avoiding the problem of excessive local stress, thereby reducing the risk of fatigue failure of the butterfly spring body 1 and extending its service life.

[0026] In this embodiment, the system response time is ≤90ms, the preload adjustment range is 60-180kN, and the stiffness fluctuation coefficient is ≤0.15 at the 100kN working point, which is more than 40% higher than that of traditional butterfly springs of equal thickness.

[0027] refer to Figure 1 In one embodiment, the butterfly spring body 1 is an annular structure with an isosceles trapezoidal cross-section, so that the butterfly spring can withstand a large load in a very small axial installation space.

[0028] refer to Figure 1As a preferred embodiment, the inner diameter of the butterfly spring body 1 is 40mm to 60mm, the outer diameter of the butterfly spring body 1 is 80mm to 100mm, the thickness of the butterfly spring body 1 near the center is 3mm to 5mm, and the thickness of the butterfly spring body 1 away from the center is 1.5mm to 2.5mm.

[0029] A variable-section gradient butterfly spring body 1 (center thickness 3mm → edge thickness 1.5mm) is used, and the nonlinear stiffness is optimized through finite element parametric modeling, so that the adjustable preload range is expanded to 60-180kN, and the stiffness fluctuation coefficient is reduced from 0.25 to 0.12.

[0030] refer to Figure 1 As an embodiment, the material of the butterfly spring body 1 is a nickel-based alloy, and a diamond-like coating is deposited on the surface of the butterfly spring body 1. The friction coefficient after the diamond-like coating is deposited on the surface of the butterfly spring body 1 is ≤0.15, and the linear expansion coefficient after the diamond-like coating is deposited on the surface of the butterfly spring body 1 is ≤13×10 -6 / ℃.

[0031] Using Inconel 718 nickel-based alloy and DLC (diamond-like carbon) coating, the risk of seizure under temperature differences of -40℃ to +60℃ is reduced by 60%, the uniformity of high-temperature stress distribution is improved by 22%, and the 1000-hour thermal relaxation rate is reduced from 15% to 4%.

[0032] refer to Figure 1 and Figure 2 The present invention also discloses a butterfly spring group, which uses the butterfly spring described above and includes two butterfly spring bodies 1 with outer rings interlocked. Because the deformation of a single butterfly spring body is limited, the total deformation stroke can be linearly increased by interlocking the outer rings to meet the scenario requiring large displacement compensation.

[0033] refer to Figure 2 The present invention also discloses an electro-hydraulic composite tensioning mechanism, which uses the butterfly spring group described above, including at least two butterfly spring groups connected end to end in sequence. The butterfly spring groups connected end to end are referred to as butterfly spring assembly 8. One end of the butterfly spring assembly 8 is connected to the tensioning wheel connecting piece 7, and the other end of the butterfly spring assembly 8 is connected to the driving device. The driving device can realize the movement of the butterfly spring assembly 8 along the axis of the butterfly spring. By connecting at least two butterfly spring groups in series, the adjustment range of the butterfly spring assembly 8 can be greatly improved compared with linear springs of the same size. When the tensioning force needs to be adjusted, the butterfly spring assembly 8 is driven to retract and retract by the driving device. When the driving device drives the butterfly spring assembly 8 to move toward the direction close to the tensioning wheel connecting piece 7, the tensioning force can be reduced. When the driving device drives the butterfly spring assembly 8 to move toward the direction away from the tensioning wheel connecting piece 7, the tensioning force can be increased.

[0034] One end of the tensioning wheel connecting member 7 away from the butterfly spring assembly 8 is connected to the tensioning wheel support arm 6.

[0035] refer to Figure 2 As an implementation method, a buffer 5 is provided between the driving device and the butterfly spring assembly 8, and the buffer 5 is connected to the accumulator 4. When the driving device drives the butterfly spring assembly 8 to move toward the direction close to the tensioning wheel connecting piece 7, the buffer 5 is compressed, and the oil in the buffer 5 will enter the accumulator 4. The buffering of the buffer 5 can avoid the rigid impact of the driving device on the butterfly spring assembly 8, and the compression speed can be quickly reduced. When the driving device drives the butterfly spring assembly 8 to move in the direction away from the tensioning wheel connecting piece 7, the compressed shell of the buffer 5 is stretched, and the oil in the accumulator 4 returns to the buffer 5. The replenishment of the oil in the accumulator 4 can accelerate the compensation of the rebound of the buffer 5, thereby avoiding the rigid impact of the driving device on the butterfly spring assembly 8.

[0036] It should be noted that oil is stored in the buffer 5, and the outer shell of the buffer 5 is a shell that can be deformed when subjected to force, such as a silicone shell or other shell that can be deformed when subjected to force.

[0037] The hydraulic accumulator 4 has a capacity of 2 L (pre-charge pressure 10 MPa) and absorbs high-frequency loads, reducing the peak power demand of the drive device by 40%.

[0038] refer to Figure 2 As an implementation method, a tension pressure sensor 9 for testing tension pressure is provided between the buffer 5 and the driving device. The tension pressure sensor 9 is communicatively connected with the controller 3. The controller 3 is used to control the opening and closing of the driving device. The tension pressure sensor 9 collects the value of the tension pressure applied by the driving device to the butterfly spring assembly 8 (i.e., the value of the tensioning force). When the value of the tensioning force is higher or lower than the preset value, the driving device is controlled by the controller 3 to adjust the tensioning force. The tension pressure sensor 9 is combined with the butterfly spring assembly 8 to form a closed-loop control of the tensioning force. The response time is 85ms, and the energy consumption is reduced by 35% compared with the traditional system.

[0039] refer to Figure 2 As an embodiment, the driving device includes a driving motor 2, the output end of the driving motor 2 is connected to the screw rod 10, the screw rod 10 is threadedly connected to the nut, and the nut is reciprocated in the axial direction of the screw rod 10 by the rotation of the screw rod 10, and the nut is connected to the tension and pressure sensor 9.

[0040] It should be noted that the drive motor 2 is a direct drive servo motor (50N·m, 3000rpm) that drives the screw 10 to achieve ±1mm / s precise displacement control.

[0041] refer to Figure 2 As an embodiment, the driving device is an electric push rod, which is connected with the tensile and compressive force sensor 9.

[0042] It is to be understood that the application is not limited to the details of the above-exemplified embodiments and can be implemented in various other forms without deviating from the spirit or essential characteristics of the application. The embodiments are to be considered in all respects as illustrative and not restrictive, the scope of the application being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference signs in the claims should not be construed as limiting the claim concerned.

Claims

1. A butterfly spring, characterized in that: The butterfly spring comprises a butterfly spring body, wherein the wall thickness of the butterfly spring body gradually decreases from the center to a direction away from the center.

2. The butterfly spring according to claim 1, characterized in that: The butterfly spring body is an annular structure with an isosceles trapezoidal cross-section.

3. The butterfly spring according to claim 2, characterized in that: The inner diameter of the butterfly spring body is 40mm to 60mm, the outer diameter of the butterfly spring body is 80mm to 100mm, the thickness of the butterfly spring body near the center is 3mm to 5mm, and the thickness of the butterfly spring body away from the center is 1.5mm to 2.5mm.

4. The butterfly spring according to claim 1, characterized in that: The material of the butterfly spring body is nickel-based alloy, with diamond-like coating deposited on the surface, friction coefficient ≤ 0.15, linear expansion coefficient ≤ 13×10 -6 / ℃.

5. A butterfly spring assembly, characterized in that: The butterfly spring according to any one of claims 1 to 4 comprises two butterfly spring bodies with outer rings interlocked with each other.

6. An electro-hydraulic composite tensioning mechanism, using the butterfly spring assembly according to claim 5, characterized in that: It includes at least two butterfly spring groups connected end to end, a tensioning wheel connecting piece arranged at one end of the butterfly spring group connected end to end, and a driving device arranged at the other end of the butterfly spring group connected end to end to realize the extension and contraction of the butterfly spring group.

7. The electro-hydraulic composite tensioning mechanism according to claim 6, characterized in that: A buffer is provided between the driving device and the butterfly spring group located near one end of the driving device, and the buffer is connected to the accumulator.

8. The electro-hydraulic composite tensioning mechanism according to claim 7, characterized in that: A tension and pressure sensor for testing tension and pressure is provided between the buffer and the driving device. The tension and pressure sensor is communicatively connected with a controller, and the controller is used to control the opening and closing of the driving device.

9. The electro-hydraulic composite tensioning mechanism according to claim 8, characterized in that: The driving device includes a driving motor, a screw connected to the output end of the driving motor, and a nut threadedly connected to the screw and capable of reciprocating along the axial direction of the screw, and the nut is connected to the tension and pressure sensor.

10. The electro-hydraulic composite tensioning mechanism according to claim 8, characterized in that: The driving device is an electric push rod, and the electric push rod is connected to the tension and pressure sensor.

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