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(11) | EP 2 751 426 B1 |
| (12) | EUROPEAN PATENT SPECIFICATION |
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| (54) |
COMPRESSOR BLOCK VERDICHTERBLOCK BLOC COMPRESSEUR |
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| Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention). |
Field of the Invention
[0001] The present invention relates to a compressor block, in particular, a reciprocating compressor block (preferably employed in cooling systems).
[0002] The compressor block in question was developed with the aim of providing a rigid and resistant structure using a fewer amount of raw materials for its manufacture.
Background of Invention
[0003] Reciprocating compressors, in particular those employed in cooling systems are composed essentially by an electric motor and by means to promote compression of a working fluid (coolant fluid). In general, the means to promote the compression of a working fluid comprise at least one piston-cylinder assembly, wherein the piston is able to be reciprocally moved within the cylinder (where the working fluid can be compressed).
[0004] In this sense, the movement of the piston is conventionally related (directly or indirectly) to the movement provided by the electric motor. Typically, the coupling between these elements is performed by a connecting rod, which is capable of transferring and / or transform the movement of the motor (motor rotor) to the piston.
[0005] The arrangement of components of a reciprocating compressor, as described above is typically provided by associating them into a single block, which is associated with the compressor housing.
[0006] An example of a compressor block embraced by the state of the art is illustrated in Figure 1. In this figure, it is noticed that said compressor block 11 comprises a plate 16 for mounting a valve assembly (not shown) associated with the piston guide 13 (not shown) to a housing 12 for the rotor of the motor (not shown), and extensions 14 to support the block 11 in the compressor housing (not shown). While these elements have been modularly cited, it should be also stated that the compressor block 11 it is a one-section, integral body, and these elements are interconnected by means of plates 17 which (despite comprising some points of reduction of material 15) require a high amount of raw material for its production.
[0007] It was also observed that the current state of the art includes models of compressor blocks designed to reduce the demand of raw material for its production.
[0008] A first example of this type of construction is described in US 4,115,035, where it is possible to notice a block for reciprocating compressor of refrigerator whose objective is to minimize the amount of material required for its manufacture. This block comprises a geometry formed by a substantially triangular shaped plate, joining the operating regions of the block (opening for mounting the motor shaft; shirt jacket and two pressure damping chambers). This solution, despite employing a relatively low amount of material in its manufacture, has the disadvantage of concentrating all tensions resulting from operational efforts of the compressor in a single region of the block: the substantially triangular shaped plate. In addition, it results in excessive acoustic transmissibility because it is a flat plate.
[0009] A second example can be found in the document US 3,666,380 which also discloses a block for reciprocating compressor of refrigerators, with a greatly simplified embodiment, apparently reducing the amount of material, provided with a similar geometry to the object described in US 4,115,035. However, in a more simplified embodiment, not comprising the pressure damping chambers and comprising an extension from the opening for mounting the drive axle, extending to the compressor housing where it is associated with a vibration damping element. The compressor block obtained from this embodiment, although apparently requiring less material to be manufactured, requires the use of reinforcements to ensure its rigidity. Such reinforcements tend to increase the weight of the block and, consequently, the amount of material used in making the same.
[0010] Yet, other examples of compressor blocks which do not aim to reduce the demand of raw material for its production are described below:
A third example of compressor block can be found in the document WO 2011/022799, which discloses a compressor block comprising a shaft hub, a piston hub and a physical connection between the shaft hub and the piston hub. Said physical connection is defined by two lateral legs (60a) and a base leg (60b). The main object of WO 2011/022799 is to provide a compressor block exhibiting elastic deformation capacity between the working angle of shaft hub relative to the working angle of piston hub, wherein, to this effect, the piston hub can be controllably moved in relation to the legs of the compressor block. A fourth example of compressor block can be found in the document EP0507091, which discloses a motor-compressor unit with an "optimized" compressor block, wherein said compressor block comprises a rear end, two lateral edges, a flat part and four arms. It can be inferred that all these structures are integrally joined therebetween, thereby defining a monoblock body. It is specifically verified that the rear end is integrally joined to the two lateral edges and to the flat part. The main object of EP 0507091 is to provide a compressor block whose geometry is as simple and uniform as possible to allow for it to be manufactured by stamping.
[0011] Other examples of compressor blocks can be found in documents WO2009/137857, US3,785,453 or US3,401,873, which are not of particular relevance to the present invention.
[0012] It is noted, therefore, that the current state of the art lacks a reciprocating compressor block, using a small amount of material in its manufacture, providing a high mechanical resistance to the efforts derived by the operation and which provides also a good capacity to dissipate the heat resulting from the operation of the compressor.
Objectives of the Invention
[0013] Thus, it is one of the objectives of the present invention to provide a reciprocating compressor block that uses a low amount of raw material in its manufacture.
[0014] It is another objective of the present invention to disclose a reciprocating compressor block having low weight and high mechanical strength.
[0015] It is also another objective of the present invention to disclose a reciprocating compressor block with a low acoustic transmission through the elimination of the conventional flat plates.
[0016] It is yet another objective of the present invention to provide a reciprocating compressor block capable of providing a good dissipation of heat absorbed during the operation of the compressor.
Summary of the Invention
[0017] The objectives of the present invention are achieved by the compressor block as claimed in claim 1, which comprises at least one opening of driving member frontol extensions of support and at least one mounting portion (for mounting the plate of valves). The compressor block disclosed herein comprises at least one first means of structural connection between the mounting portion (for mounting the plate of valves) and the frontal extensions of support defined by at least one structural wall, and at least one second means of structural connection between the mounting portion (for mounting the plate of valves) and the frontal extensions of support defined by at least one structural wall.
[0018] According to the present invention, the walls comprising at least one section of physical association between each other and define at least partially the main perimeter of the compressor block. Preferably, the walls are fundamentally symmetrical.
[0020] Preferably, the compressor block disclosed herein comprises at least one reinforcement disposed between frontal extensions of support.
Brief Description of Figures
[0022] The present invention will be described in detail based on the figures listed below, including:
Figure 1 illustrates a block compressor belonging to the current state of the art, seen in isometric perspective;
Figure 2 illustrates the compressor block now disclosed, in isometric perspective;
Figure 3 illustrates the compressor block now disclosed, seen in top view, and
Figure 4 illustrates, schematically, a preferred assembly of the compressor block now disclosed.
Detailed Description of the Invention
[0023] According to the main concept of the present invention, there is shown a block compressor that does not use a horizontal plate for the junction of the functional parts of the block (as done by prior art), consisting, however, of a structure of low weight, high rigidity and requiring a small amount of raw materials for their manufacture.
[0024] The preferred embodiment proposed by the present invention is disclosed in details in Figures 2 to 4, which shows the compressor block 21, object of the present invention.
[0025] The compressor block 21 comprises at least one passage opening of the driving member 22 capable of allowing the passage of a piston actuator means 32, wherein such piston actuator means 32 preferably is an eccentric shaft coupled to the motor shaft 31 acting as a crankshaft. It should be noted, however, that any other equivalent means of actuating the piston 32 equivalent can be used without alteration of the scope of the invention.
[0026] In the preferred embodiment the block 21, at least one piston jacket 23 is disposed in a position that is substantially perpendicular to the passage opening of the driving member 22, and said piston jacket 23 is capable of housing the piston of the compressor 34. The piston jacket 23 is designed to accommodate and allow the piston 34 to perform oscillating sliding movements inside itself so that it, in order to move in the direction of the passage opening of the driving member 22, admits the refrigerant gas and compresses the same when they move in the opposite direction.
[0027] Thus, it is extremely important that the inner surface of the piston jacket 23 is provided with a high dimensional accuracy (so as to ensure an ideal gap 34 with the piston, ensuring tightness) and an appropriate surface roughness (in order to minimize the friction between the piston 34 and piston jacket 23, thereby reducing power loss and heating of both components).
[0028] Both the admission to the compression process and the distribution of the refrigerant gas already compressed are managed from a block of valves (not shown) which is mounted on mounting portion 26 disposed along with the piston jacket 23.
[0029] Said block of valves defines the geometry of the mounting portion 26, and preferably, but not necessarily, comprises a valve assembly of the "bypass" type to enable the flow of gas only in the desired direction, however, that block valves may be replaced by equivalent means, without thereby affecting the scope of the present invention.
[0030] Said block 21 also comprises at least one, but preferably four support extensions 24 arranged at the ends of the block, the extensions being subdivided into two frontal extensions of support 24a and two rear support extensions 24b. These extensions support 24 are intended to allow the block 21 to be mounted on the compressor housing.
[0031] The block 21, illustrated in the figures 2 to 4, comprises at least one structural wall 28a defining at least one first means of structural connection, joining the mounting portion 26 and the frontal extensions of support 24a and at least one structural wall 28b defining at least one second means of structural connection, joining the mounting portion 26 and the frontal extensions of support 24a. In a preferred embodiment, the walls 28a and 28b comprise at least one section of physical association with each other.
[0032] In a preferred embodiment, the block 21 comprises two fundamentally symmetrical structural walls 28a.
[0033] Also in a preferred embodiment, the block 21 comprises two fundamentally symmetrical structural walls 28b.
[0034] Thus, the walls 28a and 28b are preferably provided with fundamentally curvilinear sections and define the perimeter of the main block 21 being defined by two pairs of walls, each pair being comprised by a structural wall 28a and a structural wall 28b arranged symmetrically and physically associated to each other.
[0035] Additionally, there is provided the use of a reinforcement 24c joining the two frontal extensions of support 24a. In a preferred embodiment, said reinforcement 24c is provided with a curvilinear geometry.
[0036] These walls 28a and 28b provide rigidity to the block of the present invention, since they provide mechanical strength on many degrees of freedom, even if they are composed of slim cross sections. Thus, it is noted that the cross sections of the structural walls 28a and 28b are arranged in such a way to support the loads in the direction of their higher moment of inertia, providing a high rigidity with a small amount of required raw material, thus resulting at a block 21 that is more lightweight and economical.
[0037] Referring to the passage opening of the driving member 22, it is noted that it is associated with the structure of the block 21 by means of at least one, but preferably four reinforcements 27.
[0038] It should be also noticed that in the structure of the block 21, the constructive arrangement formed by rigid or permanent connection of the walls 28a and 28b and of the reinforcements 27 results in a large amount of openings 25 where there is no raw material. Such openings 25 represent a high percentage of the volumetric space defined by the block 21 due to the fact that there are spaces without raw materials, representing a significant percentage of raw material savings, when compared to the compressor blocks of the state of the art.
[0039] Due to the existence of such openings 25 it is also obtained a good relation "volume / surface of heat exchange" which provides a considerable improvement in the dissipation of heat by convection, when compared to the compressor block of the state of the art. Once the compressor block 21 is able to dissipate its heat with greater easiness, the result is a lower average temperature of the block 21 representing a higher thermal efficiency of the compressor.
[0040] The apertures 25 associated to the structures 28a and 28b also provide low acoustic transmissibility to the block of the event, since they provide thereto the absence of flat plates which vibrate more easily compared to the blocks of the compressor of the state of the art.
[0041] Still with reference to the structural walls 28b, it is noted in Figure 4 that they define an area of action of the connecting rod 33, bypassing the movement of the driving member of the piston 32, in the case represented by an eccentric shaft which interconnects an electric motor 31 to a connecting rod 33. At this point, by imposing rotational motion to the motor shaft 31 the eccentric shaft will move on a rotary trajectory under the same center of the motor shaft, but radially displaced, providing an alternate linear movement to the piston 34 associated to the connecting 33.
[0042] In a preferred embodiment, the block 21 is formed by a metallic material single piece, thus, the block 21 is preferably made by a casting process that may, both the material and the process of obtaining, be altered without the scope being affected. An example of an alternative embodiment consists, for example, of the adoption of a block 21 being formed of a polymeric material made by a process of plastic injection.
at least one first means of structural connection between the mounting portion (26) and frontal extensions of support (24a) defined by at least one structural wall (28a);
at least one second means of structural connection between the mounting portion (26) and the frontal extensions of support (24a) defined by at least one structural wall (28b);
the structural walls (28a, 28b) comprising at least one section of physical association between each other; the compressor block being characterized in that it further comprises:
a plurality of reinforcements (27) connecting the passage opening of driving member (22) to the structure of the block (21);
the structural walls (28a, 28b) and the reinforcements (27) comprising at least one section of physical association between each other;
the physical association between structural walls (28a, 28b) and reinforcements (27) defining a plurality of openings (25), and
the structural walls (28a, 28b) defining, partially, the main perimeter of the compressor block (21).
wenigstens erste Einrichtungen zur strukturellen Verbindung zwischen dem Montageteil (26) und den frontale Fortsätzen zur Stützung (24a), definiert durch wenigstens eine strukturelle Wand (28a);
wenigstens zweite Einrichtungen zur strukturellen Verbindung zwischen dem Montageteil (26) und den frontale Fortsätzen zur Stützung (24a), definiert durch wenigstens eine strukturelle Wand (28b);
wobei die strukturellen Wände (28a, 28b) wenigstens einen Abschnitt einer physikalischen Verbindung untereinander enthalten; wobei der Kompressorblock dadurch gekennzeichnet ist, dass er ferner enthält:
eine Mehrzahl von Verstärkungen (27), die die Durchlassöffnung eines Antriebselements (22) mit der Struktur des Blocks (21) verbinden;
wobei die strukturellen Wände (28a, 28b) und die Verstärkungen (27) wenigstens einen Abschnitt einer physikalischen Verbindung untereinander enthalten;
wobei die physikalische Verbindung zwischen den strukturellen Wänden (28a, 28b) und den Verstärkungen (27) eine Mehrzahl von Öffnungen (25) definiert, und
wobei die strukturellen Wände (28a, 28b) teilweise den hauptsächlichen Umfang des Kompressorblocks (21) definieren.
au moins des premiers moyens de liaison structurelle entre la partie de montage (26) et les extensions frontales de support (24a) définis par au moins une paroi structurelle (28a) ;
au moins des seconds moyens de liaison structurelle entre la partie de montage (26) et les extensions frontales de support (24a) définis par au moins une paroi structurelle (28b) ;
les parois structurelles (28a, 28b) comprenant au moins une section d'association physique entre elles, le block compresseur étant caractérisé par le fait qu'il comprend en outre :
une pluralité de renforts (27) reliant l'ouverture de passage d'élément de commande (22) à la structure du block (21) ;
les parois structurelles (28a, 28b) et les renforts (27) comprenant au moins une section d'association physique entre eux ;
l'association physique entre les parois structurelles et les renforts définissant une pluralité d'ouvertures, et
les parois structurelles (28a, 28b) définissant, partiellement, le périmètre principal du bloc compresseur (21).
REFERENCES CITED IN THE DESCRIPTION
This list of references cited by the applicant is for the reader's convenience only. It does not form part of the European patent document. Even though great care has been taken in compiling the references, errors or omissions cannot be excluded and the EPO disclaims all liability in this regard.
Patent documents cited in the description
- US4115035A [0008] [0009]
- US3666380A [0009]
- WO2011022799A [0010] [0010]
- EP0507091A [0010] [0010]
- WO2009137857A [0011]
- US3785453A [0011]
- US3401873A [0011]