GB2289112A

GB2289112A - Compressor pipe with vibration damping block

Info

Publication number: GB2289112A
Application number: GB9508997A
Authority: GB
Inventors: Maurizio Bucciarelli
Original assignee: Zanussi Elettromeccanica SpA
Current assignee: ACC Compressors SpA
Priority date: 1994-05-03
Filing date: 1995-05-03
Publication date: 1995-11-08
Anticipated expiration: 2015-05-03
Also published as: FR2719635B3; GB9508997D0; DE29507274U1; ITPN940015V0; ES1030938U; ES1030938Y; GB2289112B; ITPN940015U1; IT235020Y1; FR2719635A1

Abstract

A compressor for a refrigerator or freezer has a delivery pipe 2 provided with a vibration damper block 1. The block is of extended U-shape, comprising a pair of side-by-side limbs interconnected by a convexly curved web, and being mounted astride the pipe. The block 1 is formed in one piece and has, at a position corresponding to the end portions of its limbs adjacent the web of the U, a constriction 4 which decreases in width towards the web of the U, merging into a cavity which is of a cross-section in the form of a circular arc having a diameter 5 greater than the minimum width of the constriction. The block is preferably made of thermoplastic polyester material. <IMAGE>

Description

COMPRESSOR WITH IMPROVED DAMPING BLOCK The invention relates to a sealed compressor, in particular for domestic refrigerators and freezers, in which the motor and the compression unit are accommodated in the interior of a sealed container, particularly but not exclusively of metal.

At the present time that type of compressor is provided with a pipe for delivery of the compressed gas from the head of the compressor towards the internal wall of the sealed container which encloses the compressor.

During operation of the compressor that pipe, in contact with the internal structure of the compressor, is subjected to forces and vibration thereof and transmits same to the external container which as a result for that reason also can be undesirably noisy.

In order to reduce such forces it is known to provide a vibration damper element or block disposed astride the pipe and usually of an extended U-shape and of such dimensions that the limbs of the element are spaced from each other by a distance which is less than the diameter of the pipe but they are not rigid; in that way it is possible to fit the damper element astride the pipe by simply forcing it lightly in such as way that the pipe slides between the limbs of the U-shape and is disposed in a stable position at the bottom of the passage defined by the limbs.

That block is usually made from a strip of elastomer material, especially rubber, which is bent and suitably held by a metal spring member acting as a fastener or clip.

Although that construction is effective from the functional point of view, it is found to be wanting from the point of view of reliability and durability since the rubber can suffer degradation due to the refrigerating gas which is used as a refrigerating fluid and which is slightly corrosive, and the oils which are mixed therein, and also because of the temperature involved, to which it is subjected.

In addition the operating temperature at the delivery pipe which is disposed in the interior of the compressor can easily attain 1200C, and that accelerates the process of deterioration of the rubber element.

The main effect of that deterioration is that the passage in the block, which accommodates the pipe, is enlarged due to corrosion and wear, with the result of a slackening of the mechanical bond between the pipe and the block and finally loss of the damping capabilities of the block.

It would therefore be desirable, and this is the aim of the present invention, to improve the design configuration of such compressors and the associated damping elements to overcome the disadvantage described in a sound, definitive, simple and economic manner.

According to the present invention, there is provided a compressor for a refrigerator or freezer, provided with a container, a vibration damper element and a pipe for delivery of compressed gas towards the exterior of the container of the compressor, said vibration damper element being of an extended U-shape comprising a pair of side-by-side limbs interconnected by a convexly curved web, and being mounted astride said pipe, wherein said vibration damper element is formed in one piece and has, at a position corresponding to the end portions of its limbs adjacent the web of the U, a constriction which decreases in width towards the web of the U, merging into a cavity having a maximum width greater than the minimum width of said constriction and smaller than the diameter of said pipe.

The invention will be further described by way of non-limitative example with reference to the accompanying drawings, in which: Figure 1 is a front view of a damping element according-to the invention; Figure 2 is a view on an enlarged scale of a portion of the element shown in Figure 1; and Figure 3 is a simplified perspective view of the damping element according to the invention when fitted in use.

The invention involves the provision of a vibration damper block 1 which is of an extended U-shape (i.e. two side-by-side limbs interconnected by a convexly curved web) to be fitted astride the delivery pipe 2, in accordance with the known art, wherein the damper element is substantially rigid and formed in one piece. In addition, at a position corresponding to the inner end portions of its inside walls 3, i.e. those ends of the walls adjacent the web of the U, it has a constriction 4 which decreases in width towards the web of the U, merging into a cavity having a maximum width 5 which is greater than the minimum width of the constriction.

In that way, when the delivery pipe 2 is inserted into the recess formed by the limbs of the block, the constriction firstly opposes the advance movement of the pipe but then, after the resistance of the constriction has been overcome and the pipe is disposed within the cavity, the constriction opposes slackening of the two components which are engaged by friction between each other, the consequence of which is mutual stable blocking thereof.

Preferably, also for production reasons, the cavity is of a cross-section in the form of a circular arc whose diameter 5 is greater than the width of the constriction.

An advantageous configuration of the block provides that its limbs are parallel and that their spacing 6 which is constant is smaller than the diameter of the delivery pipe, with an interference of less than 0.5 m/m.

That makes it possible to regulate the width of the constriction 4 with a greater degree of precision and to prevent the components coming loose in the event that for any reason whatever the constriction does not succeed in holding the delivery pipe fixed to the block which can be made of any sufficiently strong material such as for example metal; however the construction of a metal block gives rise to two disadvantages: - the first disadvantage is that thermal expansion of the metals can easily give rise to clearances and/or stresses as between the components, which are harmful in regard to the stability of the coupling thereof; and - the second disadvantage is that in any case friction between metals is normally lower and uncertain in comparison with friction between a metal and another synthetic material.

It has thus been found by experience that an advantageous embodiment of the damping block involves using a plastics material, in particular thermoplastic polyester (PBT), for example of the type known by the trade name VALOX 412 from General Electric.

In fact that material offers the numerous advantages of substantial stability, both dimensional and in in terms of stiffness at the operation temperatures, easy workability, constancy of friction with respect to the metal of the delivery pipe and thus reduced wear and tear in the working zone, making it ideal for the described use.

Although the invention has been described with reference to the example of the preferred solutions and with generally known terminology, it is not considered to be limited thereby since the man skilled in the art can make therein many structural and circuitry modifications and variations.

Claims

1. A compressor for a refrigerator or freezer, provided with a container, a vibration damper element and a pipe for delivery of compressed gas towards the exterior of the container of the compressor, said vibration damper element being of an extended U-shape comprising a pair of side-by-side limbs interconnected by a convexly curved web, and being mounted astride said pipe, wherein said vibration damper element is formed in one piece and has, at a position corresponding to the end portions of its limbs adjacent the web of the U, a constriction which decreases in width towards the web of the U, merging into a cavity having a maximum width greater than the minimum width of said constriction and smaller than the diameter of said pipe.

2. A compressor according to claim 1 wherein said cavity is of a cross-section in the form of a circular arc having a diameter greater than the width of said constriction.

3. A compressor according to claim 2 wherein said inside walls are parallel and that the spacing therebetween is smaller than the diameter of said delivery pipe for an interference of less than 0.5mm.

4. A compressor according to claim 2 or 3 wherein said damper element is made of thermoplastic polyester material (PBT).

5. A compressor constructed and arranged to operate substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.

6. A refrigerator or freezer having a refrigeration circuit comprising a compressor according to any one of the preceding claims.