GB1578863A

GB1578863A - Shock-absorbing support comprising a resilient block with cavities therein

Info

Publication number: GB1578863A
Application number: GB1893577A
Authority: GB
Original assignee: Paulstra SNC
Current assignee: Paulstra SNC
Priority date: 1976-05-06
Filing date: 1977-05-05
Publication date: 1980-11-12
Also published as: NL185302B; DE2719925A1; NL185302C; IT1081409B; NL7704901A; DE2719925C2; GB1578864A

Description

(54) SHOCK-ABSORBING SUPPORT COMPRISING A RESILIENT BLOCK WITH CAVITIES THEREIN (71) We, PAULSTRA, a Body Corporate organised and existing under the Laws of France, of 61 Avenue Marius-Aufan, 92305- Levallois-Perret, France, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: The present invention relates to a resilient support for interposition between two structures, one of which must be protected against shocks and vibrations which are liable to occur in several directions, for example between the body or engine of a vehicle and its chassis or between a freight container and the vehicle, aeroplane or ship on which it is carried.

For such purposes it is known to use blocks of elastomer having cavities therein.

In accordance with the present invention there is provided a resilient support for interposition between two structures comprising at least one block of elastomer bonded on the one hand to a fixing element for attachment to one of the structures and on the other hand to three orthogonal metal plates for attachment to the other structure, the block having respective cavities disposed between the fixing element and each of the orthogonal plates.

The cavities allow the block of elastomer, when subjected to shocks and vibrations, to work at first by flexing and shearing and thereafter, if the cavities are closed, in compression.

Each of the cavities is preferably defined between surfaces parallel to the respective plate and may open onto a free face of the block.

In a preferred form the block is a rectangular body with the faces which are bonded to the said plates enlarged by means of projections from the rectangular body, the cavities being at least partially with the said projections. This construction enables the dimensions of the cavities to be increased.

The invention will now be described in more detail with the aid of examples illustrated in the accompanying drawings, in which: Figure 1 is a perspective view of a resilient support in accordance with the invention, Figure 2 is a similar view of a second form of resilient support in accordance with the invention and Figures 3 and 4 are sections in two orthogonal planes and Figure 5 is a side elevation of a third form of resilient support in accordance with the invention.

The resilient support shown in Figure 1, which is intended to absorb shocks or vibrations in three orthogonal directions, comprises a rigid metallic member 1 in the form of a triple dihedron consisting of three plates, orthogonal to one another, which in this instance are integral with one another but, as shown in Figures 2 to 5, may be separate. A resilient block 2 in the form of a cube has three of its sides bonded respectively to the three plates of the metallic member 1, the bonding being effected by any of the conventional techniques.

For each of three perpendicular directions in which shocks may occur at least one cavity 3 is formed in the block 2. Each cavity 3 lies adjacent and generally parallel to one of the plates of the member 1 to take up shocks in a direction perpendicular to that plate. Each cavity opens at one end on a free face of the block 2.

Embedded in the block 2 there is a metallic fixing element 4 with a threaded bore 5.

The unit or assembly to be supported, such as a motor or container, can be attached to the fixing element 4 by means of a screw engaged in the threaded bore 5. The member 1 is itself provided with means for fixing it to a chassis or other assembly intended to support the load, such means comprising holes 6 for the passage of pins or the like and/or of projecting screws or pins 7 as shown in Figures 3 to 5.

In such a resilient support, the elastomer, instead of working only by compression, as would be the case if the resilient block 2 was solid, works, at least at the beginning of the reception of shocks, at one and the same time by shearing and by flexion, this flexion being exercised on the arms of elastomer adjacent to the cavities 3. It is only at the end of the process that the rest of the shock-energy is absorbed solely by compression, when the cavity concerned, corresponding to the direction of the shock, has just closed.

To sum up, the shocks are absorbed in the three directions, with substantially the same rigidity in the three axes, but with a good initial flexibility, since the shock is first absorbed by deformations in shearing and flexion, whereas it is only at the end of the process that the effect of check by compression occurs.

As is evident, the symmetry represented in the drawing is not obligatory and the form especially of the cavities could be different in various directions, if differentiation of the respective rigidities were desired.

Moreover, the cavities can be multiple in at least one or in each of the directions concerned.

Figure 1 only explains the principle of the invention, but it is possible to imagine numerous modes of realisation arising from this principle.

Thus it is that it can be desirable to increase the dimensions of the cavities, for which eventuali.y there is provided, as represented in Figure 2, an enlargement of the resilient block 2, at the side of the base connecting it to the metal support 1.

This enlargement can occur for example: -either in the direction of the width d of the said cavities, as Figure 2 supposes, which allows the increasing of this width, -or in the direction of their length p, -or in any other way.

As illustrated in Figures 3 to 5 the fixing element 4 is a rectangular metal block which is covered on five sides by a layer of elastomer forming part of the block 2, the bore 5 opening onto the remaining side of the metal block. The fixing element 4 is offset from the regions of the block 2 which are bonded to the plates 1 and the cavities 3, which lie between the fixing element 4 and the plates 1 are therefore inclined, as seen in cross-section, to the faces of the mcmbers 1 and 4.

This solution, which utilises a lesser volume of elastomer than that in the preceding solutions, will be suitable for applications evidencing less shock-energies.

In any case, the dimensions and shapes of the cavities (in oval section, parallelepipedic, trapezoidal or others) will be determined as a function of the rigidities to be obtained and, contingently, of the nature of the shocks to be filtered out.

These cavities do not have to be unique in direction and constitute a network of superposed and/or adjacent cavities.

WHAT WE CLAIM IS: 1. A resilient support for interposition between two structures comprising at least one block of elastomer bonded on the one hand to a fixing element for attachment to one of the structures and on the other hand to three orthogonal metal plates for attachment to the other structure, the block having respective cavities disposed between the fixing element and each of the orthogonal plates.

2. A resilient support as claimed in claim 1 in which each of the cavities is defined between surfaces parallel to the respective plate.

3. A resilient support as claimed in claim 1 or 2 in which each of the cavities opens onto a free face of the block.

4. A resilient support as claimed in any of claims 1 to 3 in which the plates are integral with one another.

5. A resilient support as claimed in any one of the preceding claims in which the block is a rectangular body with the faces which are bonded to the said plates enlarged by means of projections from the rectangular body, the cavities being at least partially within the said projections.

6. A resilient support as claimed in any of the preceding claims in which the fixing element is embedded in the block.

7. A resilient support as claimed in any of the preceding claims in which the fixing element is a metallic element formed with a screw-threaded socket.

8. A resilient support substantially as described with reference to Figure 1, Figure 2, or Figures 3 to 5 of the accompanying drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. In such a resilient support, the elastomer, instead of working only by compression, as would be the case if the resilient block 2 was solid, works, at least at the beginning of the reception of shocks, at one and the same time by shearing and by flexion, this flexion being exercised on the arms of elastomer adjacent to the cavities 3. It is only at the end of the process that the rest of the shock-energy is absorbed solely by compression, when the cavity concerned, corresponding to the direction of the shock, has just closed. To sum up, the shocks are absorbed in the three directions, with substantially the same rigidity in the three axes, but with a good initial flexibility, since the shock is first absorbed by deformations in shearing and flexion, whereas it is only at the end of the process that the effect of check by compression occurs. As is evident, the symmetry represented in the drawing is not obligatory and the form especially of the cavities could be different in various directions, if differentiation of the respective rigidities were desired. Moreover, the cavities can be multiple in at least one or in each of the directions concerned. Figure 1 only explains the principle of the invention, but it is possible to imagine numerous modes of realisation arising from this principle. Thus it is that it can be desirable to increase the dimensions of the cavities, for which eventuali.y there is provided, as represented in Figure 2, an enlargement of the resilient block 2, at the side of the base connecting it to the metal support 1. This enlargement can occur for example: -either in the direction of the width d of the said cavities, as Figure 2 supposes, which allows the increasing of this width, -or in the direction of their length p, -or in any other way. As illustrated in Figures 3 to 5 the fixing element 4 is a rectangular metal block which is covered on five sides by a layer of elastomer forming part of the block 2, the bore 5 opening onto the remaining side of the metal block. The fixing element 4 is offset from the regions of the block 2 which are bonded to the plates 1 and the cavities 3, which lie between the fixing element 4 and the plates 1 are therefore inclined, as seen in cross-section, to the faces of the mcmbers 1 and 4. This solution, which utilises a lesser volume of elastomer than that in the preceding solutions, will be suitable for applications evidencing less shock-energies. In any case, the dimensions and shapes of the cavities (in oval section, parallelepipedic, trapezoidal or others) will be determined as a function of the rigidities to be obtained and, contingently, of the nature of the shocks to be filtered out. These cavities do not have to be unique in direction and constitute a network of superposed and/or adjacent cavities. WHAT WE CLAIM IS:

1. A resilient support for interposition between two structures comprising at least one block of elastomer bonded on the one hand to a fixing element for attachment to one of the structures and on the other hand to three orthogonal metal plates for attachment to the other structure, the block having respective cavities disposed between the fixing element and each of the orthogonal plates.