SE500084C2 - Resilient, power transferring spring element - Google Patents

Abstract

A power-transmitting spring element has end plates (10) and a substantially cylindrical elastomer body (13) inserted between the end plate surfaces facing one another. A number of spaced-apart annnular elements (15) are inserted in and connected to the elastomer body (13). An intermediate ring (14), whose two opposite surfaces are concave, is inserted centrally in the elastomer body (13). The surfaces of the end plates (10) facing one another are convex, and the annular elements (15) arranged between the convex surfaces of the end plates and the intermediate ring (14) are correspondingly domed. The end plates (10), the elastomer body (13), theintermediate ring (14) and the annular elements (15) have a through hole through which extends a rod-shaped connecting element (17) and which is of larger width than the connecting element. On the outside, the end plates (10) have cup-shaped seats (21) engaging circumferential abutment surfaces (20) projecting from the connecting element (17).

Description

15 20 25 30 35 2 The link element between the end plates also ensures that an excessive tensile load does not cause the rubber body to become detached from the end plates. The known spring element does not have as good properties when it comes primarily to transmitting shear and bending movements between the wheel axle and the vehicle frame or bogie frame. The reason for this lack of the known spring element is that the large stresses which occur in the rubber body and in particular in the mounting surfaces of the rubber body against the end plates and vulcanized metal rings can quickly lead to breakage at or near the mounting surfaces with consequent breakdown.

GB-862 173 describes and shows a spring element, which comprises a number of rubber discs and between them corrugated metal discs, which are cupped. Spring elements consist of two relatively mirror-inverted units, which are positioned so that the cupped metal plates in one unit either have their crests facing the crest of the other unit's metal plates or have their concave sides facing the concave sides on it. second unit metal plates. The two units are then connected to each other by means of a recessed intermediate plate which in the former variant is biconvex and in the latter variant is biconvex. The purpose of this design of spring elements is stated to be that one can thereby avoid the need to mechanically couple this known absorption of forces, which are the recessed metal plates to each other. spring elements are intended to be directed only in the axial direction of the element, and according to the indications in the patent specification, relative lateral movements between the end plates must not occur and must therefore be prevented. This means that this known element is not intended for transmission for other than tensile and compressive forces, which are directed in the axial direction of the element, and that the element is therefore not suitable for transmitting shear and bending movements between two components, which are connected with each other by means of the known spring element. 10 15 20 25 30 35 084 3 An element of the same type as the spring element according to GB-A-862 173 is shown in DE-C-718 344, which relates to a wheel suspension for a motor vehicle. In this case, the rubber discs, the metal discs and the intermediate disc are designed as rings, so that the spring element has an axially through hole.

The intermediate plate is designed as a biconvex plate, and the cupped metal plates on either side of the intermediate plate are turned with their crest outwards towards the end plates. In this wheel suspension, the spring elements are inserted between the motor vehicle's usual leaf spring package and the pivotally suspended wheel axle. This means that the spring element absorbs mainly axial forces relative only to the spring element, ie compressive and tensile forces, since the shear and bending forces are extremely limited due to the spring element being inserted between the outer end of the wheel axle and the outer end of the leaf spring package. that the storage location of the wheel axle and the mounting end of the leaf spring package are firmly connected to each other.

The different, known spring elements have different disadvantages, which either limit the durability of the element or adversely affect the spring characteristics of the element.

An object of the present invention is therefore to provide a spring element which has considerably better. ability to transmit shear and bending movements without breakdown and at the same time it has the good ability of the known spring element to transmit compressive and tensile forces.

This object of the invention is achieved if the spring element is designed as defined in claim 1. The subclaims state particularly preferred embodiments of the invention.

Briefly summarized, the force-transmitting spring element thus has end plates and a substantially cylindrical elastomeric body inserted between their facing surfaces. A number of mutually spaced ring elements are inserted into and connected to the elastomeric body. An intermediate ring, the two opposite end surfaces of which are concavely cupped, is inserted centrally in the elastomeric body. The facing surfaces of the end plates are convex, and the ring elements between the convex surfaces of the end plates and the biconcave intermediate ring are cupped in a corresponding manner. The end plates, the elastomeric body, the intermediate ring and the ring elements have a continuous hall, through which a rod-shaped connecting member extends and which has a greater width than this. The outside of the end plates has cup-shaped seats for engagement with circumferentially projecting shoulder surfaces on the connecting member.

The invention is based on the spring element according to SE-8- 436 480 (-US-A-4 615 513) and is based on the insight that the shortcomings of this known spring element in terms of transmission of shear and bending movements are largely due to the fact that the different layers of the elastomeric body between the different annular elements and the end plates are subjected to strong compressive and tensile stresses not only when transmitting such forces between the end plates but also when transmitting shear and bending forces. The compressive and tensile stresses place great demands on the adhesion between the elastomeric material and the metal plates inserted therein, especially if it is desired to pour the elastomeric material layers between adjacent metal plates thin.

Especially when the spring element is obliquely loaded, so that the end plates are inclined relative to each other, the risk of failure is great by pulling the elastomeric material loose from the various plates. The end plates and the plates or rings inserted in the elastomeric body have been designed in such a way that a parallel displacement or inclination of the endplates relative to each other will lead to the elastomeric material in the elastomeric body being largely exposed only to a shear deformation. In this way, the elastomeric layers can be made thinner and thus absorb larger loads per unit area. It has been found that this object can be achieved if the different layers of the elastomeric body and the metal rings inserted in the elastomeric body are designed cupped and placed with their convex sides facing a biconvex intermediate ring placed centrally in the elastomeric body, i.e. a ring The side of the end plates facing the elastomeric body is also convexly domed. The elastic body and adjacent metal rings are adhesively connected to each other by means of an adhesive system, preferably vulcanized to each other.

As mentioned above, the coupling of the metal rings and the elastic layers leads to the transmission of static and dynamic forces from one end plate to the other largely taking place by shear forces. This is because a deformation of the elastomeric material, for example when the end plates are inclined relative to each other, propagates from or towards the outer periphery of the substantially circular-cylindrical spring package in the direction outwards from and inwards towards the center, the deformation forces being deflected by the ring element cupped surfaces and thereby to an even greater extent forcibly controlled and directed as shear forces along the cupped surfaces. This control effect is obtained both at compressive and tensile loads in the axial direction of the spring package and at shear and bending movements between the two end plates.

The accompanying drawing shows two embodiments of the spring element according to the invention. Fig. 1 shows a first embodiment from the side and partly in longitudinal section and shows the spring element in loaded condition. Fig. 2 shows a longitudinal section through a second embodiment in loaded condition. _. .

The spring element according to Fig. 1 has two cup-shaped end plates 10 of metal material. A suitable number of mounting holes 12 are distributed around the flange portion 11 of the end plates.

The plates 10 face each other with their convexly convex sides. Between the plates there is a spring package 13. This spring package has a centrally located intermediate ring 14, which is biconvex, ie has two concave opposite surfaces. The intermediate ring 14 and each end plate 10 are joined together with vulcanized elastomeric material, preferably a rubber compound having a hardness of 60-80 ° Shore, especially 65-75 ° Shore, e.g. 70 ° Shore. A suitable rubber compound contains natural rubber (NR) with a mixture of styrene butadiene rubber (SBR) to increase the toughness of the rubber mixture. 10 15 20 25 30 35 6 In the vulcanized elastomeric material between the intermediate ring 14 and each end plate 10, cupped ring elements 15 of metal material are inserted and vulcanized to divide the elastomeric material into sublayers 16 in order to achieve the desired control of the stresses. in the elastomeric material when loading the spring element. The end plates 10, the ring elements 15 and the intermediate ring 14 have essentially the same design. The different 14 are one piece. cupping on its curved surfaces, which are preferably made substantially as a mantle surface on a spherical zone. A rod 17 with enlarged ends 18 extends a central heel 19 through the spring element and has itself through both a cohesive function and the function of receiving any tip loads which would be able to damage the elastomeric material and its adhesion to the various metal layers. The magnifications 18 necessary for the cohesive function are formed with an adjacent end plate 10 facing, curved surface 20 (see Fig. 2) for co-operation with a correspondingly curved surface 21 (see Fig. 2) on the end plate 10. The center of curvature of the two substantially the spherically curved surfaces 20 and 21 lie at the points A so that the spring package 13 can be deformed under the least possible force action of the engagement of the rod 17 with the end plates 10.

The enlargements 18 may have been designed or mounted on the rod 17 in any suitable manner. Thus, one magnification can be formed by a forged head while the other is formed by a threaded and welded ring or a screwed nut.

The end surfaces 22 of the rod 17, which are preferably also convexly curved, are located at a certain distance from the plane defined by the free outer surface of the flanges 11. As a result, the rod 17 will serve as a force-absorbing element in the event that the spring element would be exposed to excessively high shock loads in the compressive direction. The spring element according to the invention is characterized in that the end plates 10 and the intermediate plates or ring elements 15 are cupped and face with their convex side against a concave surface of the middle piece or the intermediate ring 14. This cupping against the intermediate ring 14 means that, when the end plates If it is either displaced in parallel or angled relative to each other, the elastomeric material in the sublayers 16 will be largely only subjected to shear deformation. This makes it possible to make the elastic layers 16 thinner than when completely flat elastic layers are used. Because the elastomeric layers can be made thinner, they can also absorb larger loads per unit area while the spring element retains its softness during bending deformation.

The center hole 19 for the rod 17 should be designed so large that the spring package 13 is allowed to deform into an S-shape, as indicated by a dotted line in Fig. 2.

In the embodiment according to Fig. 1, the spring package is vulcanized directly on the end plates 10, which is the preferred one. Due to the cupping of the end plates, the spring package can also be clamped between the end plates and thus form- and force-bonded connected thereto, as shown in Fig. 2. In this case, the spring package has cupped ring elements 23 which are coiled together with the adjacent elastic layer 16 and pressed against the convexly curved surface of the end plate 10.

In the embodiments shown, the elastomeric material on each side of the intermediate ring 14 is divided into four sublayers 16 by means of three ring elements 15. However, more or fewer sublayers and ring elements can be used, if desired.

Claims (4)

LH Cñ (3 10 15 20 25 30 35 PATENT REQUIREMENTS 1. A resilient, power-transmitting spring element having two end plates (10), a substantially cylindrical elastomeric body (13) located between them, a number of mutually spaced, ring elements (15) inserted into the elastomeric body and connected thereto, and a mechanical connecting means (17), which is arranged between the end plates (10) and extends through the elastomeric body and the ring elements inserted therein and which is arranged to limit the extent to which the end plates (10) can be pulled away from each other during tensile loading. on the spring element, characterized in that it has a central ring (14) inserted centrally between the end plates (10) in the elastomeric body (13), the two opposite surfaces of which are concavely cupped, that the end plates (10) face each other facing surfaces are convex and that the ring elements (15) are cupped and placed correspondingly between the end plates (10) and the intermediate ring (14), that the connecting element (17) is rod-shaped, that the end plates (10), ring the elements (15) and the intermediate ring (14) have a through hole (19), through which the connecting element (17) extends and which has a larger diameter than this, and that the end plates (10) have cup-shaped seats on their outwardly facing side (21) around the hole (19) and that the ends (18) projecting outside the end plates (10) have circumferential shoulder surfaces (20) which have a larger diameter than the through hole (19) and which have a for engagement with the cup-shaped seats (21) adapted arched shape. Spring element according to claim 1, characterized in that the cup-shaped seats (21) and the curved shoulder surfaces (20) are substantially spherically shaped - with their respective centers of curvature located substantially at the center (A) of the outwardly facing side of the end plates (10). . Spring element according to claim 1 or 2, characterized in that the end surfaces of the elastomeric body are vulcanized directly against the end plates (10). 10 15 20 25 30 35 9 Spring element according to claim 1 or 2, characterized in that the end surfaces of the elastomeric body are vulcanized on their respective shell-shaped metal ring (23), which in the mounted condition of the elastomeric body abuts against the convex surface of the adjacent endplate (10).