Spherical hinge with one-way deflection deformation characteristic

Abstract

A spherical hinge with the one-way deflection deformation characteristic comprises a metal core shaft on the innermost layer, a metal outer sleeve on the outermost layer and a rubber body connecting the core shaft and the outer sleeve into a whole, flat squares used for assembling are arranged at the two ends of the core shaft, and limiting mechanisms connected to the outer sleeve are arranged on the two sides of the two flat squares. The included angle between the connecting line between the centers of the two limiting mechanisms on the two sides of the same flat square and the axis of the assembling hole in the flat square is 90 + / -5 degrees. The limiting mechanisms are arranged on the two sides of the flat square, when the mandrel displaces, the flat square is prevented from displacing through the limiting mechanisms, and then the mandrel is prevented from displacing. Meanwhile, the limiting mechanism is connected to the outer sleeve, so that relative displacement between the limiting mechanism and the outer sleeve is avoided, displacement of the mandrel and the outer sleeve in the direction is avoided, and the one-way deflection deformation characteristic is achieved.

Description

TECHNICAL FIELD

[0001] The present application relates to a ball hinge, in particular to a ball hinge with one-way deflection deformation characteristics. BACKGROUND

[0002] As a widely used connecting structure, the ball hinge is usually composed of a metal core shaft in the innermost layer, a rubber layer in the middle and a metal outer sleeve in the outermost layer, and generally has a deformation ability of six degrees of freedom, so it is widely used in flexible connection and damping function components of various mechanical devices. However, in some mechanisms composed of rod systems, it is required to have a large deformation in some directions and to limit the deformation in some other directions, so as to achieve a specific control function. In the current ball hinge structure, the service life of the ball hinge is usually considered to improve the service life, and the one-way deformation characteristics are less considered, so it cannot meet the use requirements. SUMMARY

[0003] The present application proposes a ball hinge with one-way deflection deformation characteristics to meet specific use requirements, aiming at the fact that the current ball hinge cannot achieve specific control function in structure.

[0004] The technical means adopted by the present application to solve the above problems is: a ball hinge with one-way deflection deformation characteristics, comprising a ball hinge main body formed by vulcanizing a core shaft and an outer sleeve by a rubber body, the core shaft has flat sides at both ends for assembly, the two sides of the two flat sides are provided with limiting mechanisms connected to the outer sleeve, and the included angle between the center line of the two limiting mechanisms on the same flat side and the axis of the assembly hole on the flat side is 90±5°. The limiting mechanism avoids the assembly hole at both ends to avoid interference during assembly.

[0005] Further, the limiting mechanism comprises a wear-resistant limiting block close to the flat side, a fixed block connected to the outer sleeve, and a rubber layer connecting the wear-resistant limiting block and the fixed block into a whole. The connection between the fixed block and the outer sleeve ensures that there is no relative displacement between the limiting mechanism and the outer sleeve.

[0006] Further, in the initial state, the outer diameter of the outer sleeve is larger than the outer diameter of the fixed block.

[0007] Further, in the initial state, the difference between the outer diameter of the outer sleeve and the outer diameter of the fixed block is 0.5 or more.

[0008] Further, there is a gap between the limiting mechanism and the flat side. The limiting mechanism does not interfere with the displacement of the core shaft in another direction.

[0009] Further, the gap Gap is calculated as: Gap=A1×(cotα2-cotα1)+Δ, wherein: A1 is the distance from the center position of the mandrel assembly hole to the farthest contact point of the wear-resistant limit block; angle α2 is the maximum angle allowed between the limit direction mandrel and the outer sleeve; angle α1 is the minimum angle allowed between the limit direction mandrel and the outer sleeve; the difference between the two angles represents the maximum angle change allowed between the limit direction mandrel and the outer sleeve; Δ is the life compensation, which is determined according to the wear rate of the selected wear-resistant limit block material and the design life of the ball hinge. Avoiding that the gap is too large to cause the mandrel to displace too much in this direction and cannot achieve the effect of limiting displacement.

[0010] Further, a friction pair is formed between the wear-resistant limit block and the flat side surface, and the friction coefficient μ of the friction pair satisfies μ≤a(T max∥ -K t ×(α2-α1)) / {[T max⊥ -K t ×(α2-α1)] / A1}, wherein: a is a torque ratio, generally 0.1-0.3; T max∥ is the maximum allowed torque parallel to the assembly hole axis plane; K t is the deflection stiffness of the ball hinge; angle α2 is the maximum angle allowed between the limit direction mandrel and the outer sleeve; angle α1 is the minimum angle allowed between the limit direction mandrel and the outer sleeve; the difference between the two angles represents the maximum angle change allowed between the limit direction mandrel and the outer sleeve; T max⊥ is the maximum allowed torque perpendicular to the assembly hole axis plane; A1 is the distance from the center position of the mandrel assembly hole to the farthest contact point of the wear-resistant limit block.

[0011] Further, the rubber body is located between the intermediate part of the outer sleeve and the mandrel body, and the rubber layer is located between the flat square and the fixed block.

[0012] Further, the rubber layer and the rubber body are connected as a whole. Simplify the operation during vulcanization.

[0013] Further, the width of the fixed block, the rubber layer and the wear-resistant limit block along the axial direction of the assembly hole is equal.

[0014] Further, the width of the limiting mechanism along the axial direction of the assembly hole is greater than the height of the flat square along the axial direction of the assembly hole.

[0015] Further, in the free state, both ends of the limiting mechanism along the width direction thereof protrude beyond both ends of the flat square along the axial direction of the assembly hole.

[0016] Further, the distance between the wear-resistant limit block and the ball hinge body is greater than the allowed displacement value of the mandrel in the axial direction. Avoid interfering with the axial displacement of the mandrel.

[0017] The beneficial effects of the present application are: 1. This invention provides limiting mechanisms on both sides of the flat section. When the mandrel is displaced, the limiting mechanisms prevent the flat section from shifting, thereby preventing the mandrel from shifting as well. Simultaneously, by connecting the limiting mechanisms to the outer sleeve, relative displacement between the limiting mechanisms and the outer sleeve is prevented, thus avoiding displacement of the mandrel and the outer sleeve in this direction, thereby achieving unidirectional deflection deformation characteristics.

[0018] 2. By setting a gap between the limiting mechanism and the flat square, the present invention allows the mandrel to still be relatively displaced with the outer sleeve along the axis of the assembly hole, thus ensuring the deformation capability of the ball joint in this direction. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the overall structure of Example 1; Figure 2 for Figure 1 Cross-sectional view; Figure 3 for Figure 1 Side view diagram; Figure 4 for Figure 2 Enlarged view of a portion; Figure 5 This is a schematic diagram of the mandrel structure in Example 1; Figure 6 This is a schematic diagram of the dimensions of Example 1; In the diagram: 1. Outer sleeve, 2. Rubber body, 3. Mandrel, 31. Mandrel body, 32. Flat square, 33. Assembly hole, 4. Limiting mechanism, 41. Fixing block, 42. Rubber layer, 43. Wear-resistant limiting block. Detailed Implementation

[0020] The present invention will be further described below with reference to the accompanying drawings. The drawings are for illustrative purposes only, representing schematic diagrams rather than actual physical objects, and should not be construed as limiting the scope of this patent. To better illustrate the embodiments of the present invention, some components in the drawings may be omitted, enlarged, or reduced, and do not represent the actual dimensions of the product. It is understandable to those skilled in the art that some well-known structures and their descriptions may be omitted in the drawings. Example 1

[0021] A ball joint with unidirectional deflection deformation characteristics, such as Figures 1-3 As shown, it includes an outer sleeve 1, a rubber body 2, a spindle 3, and a limiting mechanism 4. The spindle 3 is located in the innermost layer of the ball joint, the outer sleeve 1 is located in the outermost layer of the ball joint, and the rubber body 2 is located between the spindle 3 and the outer sleeve 1 to vulcanize and bond the spindle 3 and the outer sleeve 1 to form the main body of the ball joint. There are four limiting mechanisms 4 in total, which are symmetrically arranged in pairs at both ends of the axial direction of the outer sleeve 1 and are located on both sides of the flat square of the spindle 3.

[0022] like Figure 5As shown, the mandrel 3 includes a mandrel body 31 in the middle and two flat sides 32 at both ends, each of which has an assembly hole 33 in the middle for assembling the spherical hinge. In this embodiment, the mandrel body 31 is a cylindrical structure, and the flat sides 32 are cubic structures with chamfers at four edges to avoid sharp corners at the edges. However, the specific shape of the mandrel body 31 and the flat sides 32 is not particularly limited, and other shapes can be selected according to the performance requirements of the spherical hinge, such as a spherical mandrel body 31. As shown Figure 1 As shown, the center line between the two limiting mechanisms 4 at the same flat side 32 is perpendicular to the axis of the assembly hole 33 on the flat side 32 (of course, when the two lines are nearly perpendicular, the included angle between them is 90±5°), so that the limiting mechanism 4 does not affect the assembly of the spherical hinge.

[0023] As shown Figures 2-4 As shown, the limiting mechanism 4 includes an outermost fixed block 41, an innermost wear-resistant limiting block 43, and a rubber layer 42 between the fixed block 41 and the wear-resistant limiting block 43, which are vulcanized together to form a whole. Overall, the rubber body 2 bonds the cylindrical sleeve 1 to the outside of the cylindrical structure 31 of the mandrel 3, and the fixed block 41 is connected with the sleeve 1 to ensure the relative position between the fixed block 41 and the sleeve 1, so that the limiting mechanism 4 cannot be displaced relative to the sleeve 1, thereby ensuring that the mandrel 3 cannot slide relative to the sleeve 1 in this direction. In this embodiment, in order to facilitate processing, reduce production cost and improve efficiency, the fixed block 41 adopts an arc-shaped structure, the inner diameter of which is equal to the inner diameter of the sleeve 1, and the outer diameter is slightly smaller than the outer diameter of the sleeve 1, so as to avoid scratching the outer surface of the fixed block 41 during press-fitting operation, and to avoid deformation of the limiting mechanism during press-fitting process. Preferably, in the initial state, the circumferential center of the outer side of the fixed block and the center of the outer side of the sleeve are both located on the axis of the cylindrical structure of the mandrel, which facilitates processing. And preferably, under the premise of ensuring strength, the difference between the outer diameter of the sleeve and the outer diameter of the fixed block is preferably 0.5 or more. At the same time, the rubber layer 42 is also designed to be thin and arc-shaped to match the shape of the fixed block 41. Of course, when the fixed block 41 is of other shapes, such as the contact surface between the fixed block 41 and the rubber layer 42 being a plane, the rubber layer 42 is also correspondingly provided in a planar shape. Moreover, the thickness of the rubber layer 42 should not be too large, only the connection effect is needed, because when the thickness of the rubber layer 42 is too large, the rubber layer 42 will be compressed under load, causing a large relative displacement between the wear-resistant limiting block 43 and the fixed block 41, which cannot achieve a good blocking effect. The surface of the wear-resistant limiting block 43 close to the rubber layer 42 is also arc-shaped, and the surface close to the flat side 32 is planar, of course, the specific shape of the two surfaces of the wear-resistant limiting block 43 is determined by the shape of the side wall of the flat side 32 and the shape of the inner wall of the fixed block 41. As shown Figure 3As shown, there is a small gap between the flat square 32 and the wear-resistant limit block 43, such as Figure 6 As shown, the calculation of the gap Gap is: Gap=A1×(cotα2-cotα1)+Δ, wherein: A1 is the distance from the center position of the assembly hole 33 of the mandrel 3 to the farthest contact point of the wear-resistant limit block 43; angle α2 is the maximum angle allowed between the limit direction mandrel 3 and the outer sleeve 1; angle α1 is the minimum angle allowed between the limit direction mandrel 3 and the outer sleeve 1; the difference between the two angles represents the maximum angle change allowed between the limit direction mandrel 3 and the outer sleeve 1; Δ is the life compensation, which is determined according to the wear rate of the selected wear-resistant limit block 43 material and the design life of the spherical hinge. When the spherical hinge is loaded and the mandrel 3 deforms along the assembly hole 33 in the axial direction relative to the outer sleeve 1, a friction pair is formed between the side surface of the flat square 32 and the surface of the corresponding wear-resistant limit block 43. The existence of the gap can ensure the deformation capacity of the spherical hinge in the axial direction of the assembly hole 33. Moreover, the friction coefficient μ of the friction pair is ≤a(T max∥ -K t ×(α2-α1)) / {[T max⊥ -K t ×(α2-α1)] / A1}, wherein: a is the torque ratio, generally 0.1-0.3; T max∥ is the maximum allowable torque parallel to the assembly hole 33 axis plane; K t is the deflection stiffness of the spherical hinge; angle α2 is the maximum angle allowed between the limit direction mandrel 3 and the outer sleeve 1; angle α1 is the minimum angle allowed between the limit direction mandrel 3 and the outer sleeve 1; the difference between the two angles represents the maximum angle change allowed between the limit direction mandrel 3 and the outer sleeve 1; T max⊥ is the maximum allowable torque perpendicular to the assembly hole 33 axis plane; A1 is the distance from the center position of the assembly hole 33 of the mandrel 3 to the farthest contact point of the wear-resistant limit block 43, so as to reduce the friction between the wear-resistant limit block 43 and the flat square 32 and improve the service life of the limiting mechanism 4.

[0024] In the embodiment, the fixed block 41 is formed in an integrated structure with the outer sleeve 1 by machining, so that the fixed block 41 and the wear-resistant limit block 43 can be vulcanized and bonded synchronously when the outer sleeve 1 and the mandrel 3 are vulcanized into a whole, and the design of the same inner diameter of the fixed block 41 and the outer sleeve 1 can use a relatively simple vulcanization mold. Figure 2As shown, the rubber layer 42 and the rubber body 2 are connected into an integral structure, rather than separating the rubber layer 42 from the rubber body 2 into multiple independent parts, so that in the vulcanization process, both the structure for sealing the rubber in the mold and the vulcanization operation can be simplified. In this embodiment, the free surface of the rubber body 2 at both end faces is in a concave structure, and the axial height of the rubber body 2 is less than the axial height of the core shaft body 31. At this time, the distance L between the end face of the wear-limiting block 43 close to the rubber body 2 and the end face of the core shaft body 31 adjacent thereto should be greater than the allowable displacement value of the core shaft 3 in the axial direction, so as to avoid interference with the axial displacement of the core shaft 3. When the free surface of the rubber body 2 at both end faces is in a convex structure, i.e., the axial height of the rubber body 2 is greater than the axial height of the core shaft body 31, the distance between the end face of the wear-limiting block 43 close to the rubber body 2 and the end face of the rubber body 2 adjacent thereto should be greater than the allowable displacement value of the core shaft 3 in the axial direction.

[0025] As shown in Figure 1 and Figure 3 The width of the fixing block 41, the rubber layer 42, and the wear-limiting block 43 in the axial direction of the assembly hole 33 is equal, which can also simplify the sealing of the rubber during the vulcanization operation. In the free state, the width of the limiting mechanism 4 composed of the fixing block 41, the rubber layer 42, and the wear-limiting block 43 in this direction is greater than the height of the flat square 32 in the axial direction of the assembly hole 33, and the two ends of the limiting mechanism 4 in this width direction both exceed the two ends of the flat square 32. Thus, when the core shaft 3 is displaced in the axial direction of the assembly hole 33, the flat square 32 still has a large area or the entire surface in contact with the limiting mechanism 4, ensuring the limiting effect. In use, when the spherical hinge is loaded, the rubber body 2 is elastically deformed, and the core shaft 3 and the outer sleeve 1 are relatively deflected. However, due to the friction pair, the core shaft 3 can only slide and deflect along the plane of the friction pair, but cannot deflect perpendicular to the plane of the friction pair, thereby realizing the one-way deflection deformation characteristic of the spherical hinge.

[0026] The above embodiments are only for illustrating the present application, and are not a limitation on the present application. Those skilled in the art can make various changes or modifications without departing from the spirit and scope of the present application, and all equivalent technical solutions should also belong to the protection scope of the present application, which should be defined by the claims.

Claims

1. A ball joint with unidirectional deflection deformation characteristics, comprising a ball joint body in which a mandrel (3) and a jacket (1) are vulcanized integrally by a rubber body (2), wherein the mandrel (3) has flat squares (32) at both ends for assembly, characterized in that: Both sides of the two flat squares (32) are provided with limiting mechanisms (4) connected to the outer sleeve (1). The angle between the line connecting the centers of the two limiting mechanisms (4) on both sides of the same flat square (32) and the axis of the mounting hole (33) on the flat square (32) is 90±5°.

2. The ball joint with unidirectional deflection deformation characteristics as described in claim 1, characterized in that: The limiting mechanism (4) includes a wear-resistant limiting block (43) near the flat side (32), a fixing block (41) connected to the outer jacket (1), and a rubber layer (42) that connects the wear-resistant limiting block (43) and the fixing block (41) into a whole.

3. The ball joint with unidirectional deflection deformation characteristics as described in claim 2, characterized in that: In the initial state, the outer diameter of the outer jacket (1) is larger than the outer diameter of the fixed block (41).

4. The ball joint with unidirectional deflection deformation characteristics as described in claim 3, characterized in that: In the initial state, the difference between the outer diameter of the outer jacket (1) and the outer diameter of the fixing block (41) is greater than 0.

5.

5. The ball joint with unidirectional deflection deformation characteristics as described in claim 2, characterized in that: There is a gap between the limiting mechanism (4) and the flat square (32).

6. The ball joint with unidirectional deflection deformation characteristics as described in claim 5, characterized in that: The gap Gap is calculated as follows: Gap = A1 × (cotα2 - cotα1) + Δ, where: A1 is the distance from the center of the assembly hole of the mandrel (3) to the farthest contact point of the wear-resistant limiting block (43); angle α2 is the maximum allowable angle between the mandrel (3) and the outer sleeve (1) in the limiting direction; angle α1 is the minimum allowable angle between the mandrel (3) and the outer sleeve (1) in the limiting direction; the difference between the two angles represents the maximum allowable angle change between the mandrel (3) and the outer sleeve (1) in the limiting direction; Δ is the life compensation amount, which is determined according to the wear rate of the selected wear-resistant limiting block (43) material and the design life of the ball joint.

7. The ball joint with unidirectional deflection deformation characteristics as described in claim 6, characterized in that: A friction pair is formed between the wear-resistant limiting block (43) and the side of the flat square (32), and the friction coefficient μ of the friction pair is ≤ a(T) max∥ -K t ×(α2-α1)) / {[T max⊥ -K t ×(α2-α1)] / A1}, where: a is the torque percentage, typically 0.1~0.3; T max∥ K represents the maximum permissible torque parallel to the plane of the assembly hole axis. t T is the deflection stiffness of the ball joint; angle α2 is the maximum allowable angle between the limiting mandrel (3) and the outer sleeve (1); angle α1 is the minimum allowable angle between the limiting mandrel (3) and the outer sleeve (1); the difference between the two angles represents the maximum allowable angle change between the limiting mandrel (3) and the outer sleeve (1); T max⊥ A1 is the maximum allowable torque perpendicular to the plane of the assembly hole axis; A1 is the distance from the center of the assembly hole (33) of the mandrel (3) to the farthest contact point of the wear-resistant limit block (43).

8. The ball joint with unidirectional deflection deformation characteristics as described in claim 1, characterized in that: The rubber body (2) is located between the outer sleeve (1) and the mandrel (3) in the middle part of the mandrel body, and the rubber layer (42) is located between the flat square (32) and the fixing block (41), and the rubber layer (42) and the rubber body (2) are connected as one unit.

9. The ball joint with unidirectional deflection deformation characteristics as described in claim 6, characterized in that: The widths of the fixing block (41), the rubber layer (42), and the wear-resistant limiting block (43) along the axial direction of the assembly hole (33) are all equal.

10. The ball joint with unidirectional deflection deformation characteristics as described in claim 9, characterized in that: The width of the limiting mechanism (4) along the axial direction of the assembly hole (33) is greater than the height of the flat square (32) along the axial direction of its assembly hole (33).

11. The ball joint with unidirectional deflection deformation characteristics as described in claim 9, characterized in that: In the free state, both ends of the limiting mechanism (4) extend beyond the two ends of the flat square (32) along the axial direction of its mounting hole (33) in the width direction.

12. The ball joint with unidirectional deflection deformation characteristics as described in claim 9, characterized in that: The distance between the wear-resistant limiting block (43) and the ball joint body is greater than the allowable displacement value of the spindle (3) axial direction.

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