The present invention concerns a suction muffler for silencing simultaneously as it absorbs a gas, more specifically a suction muffler made of resin.
In recent years, there is a strong request for equipment with high energy efficiency, as hermetic compressor used for refrigerator, etc. from the viewpoint of prevention of global warming. It is already known that, generally, a suction muffler with low thermal conductivity made of synthetic resin, etc. is suitable as suction muffler to be used for hermetic compressor.
Conventionally, as suction muffler, a product bonded by ultrasonic welding by having a projection and a concavity respectively at the bonding portion of the mating molded resin piece is known (refer to Japanese Laid-Open Patent Publication No. S59-43917, for example).
In the above-described conventional suction muffler made of resin, part of the resin is melted with ultrasonic wave and the bonded portion of the parts is pressed at the same time. For that reason, in case the bonding accuracy at the bonded portion is not so good, a problem is produced that part of the molten resin jumps out through the gap at the bonded portion, sticking to the inside of the suction muffler and solidifying there. Such part of molten resin which solidified inside the suction muffler is generally called “slag.”
Such slag produced inside the suction muffler is difficult to check for production and remove in advance, because the production of slag takes place after the bonding of resin members. Should the slag remaining inside the suction muffler be separated, it is sucked into the compressor together with the refrigerant, to present a problem of narrowing the sliding portion of the compressor, eventually leading to a stop of compressor.
The present invention provides a suction muffler capable of enhancing the reliability of compressor.
The suction muffler according to the present invention has a plurality of bonding portions made of resin members either fit to each other or put in contact with each other, and bonded by means of a resin belt formed with secondary injection molding. The surface of the bonding portion of the resin members molded in advance are bonded to each other by utilizing the heat of the molten resin injected with secondary injection molding. To that purpose, the pressing of the bonding portions and the shaking given to the suction muffler are controlled to control the production of so-called slag. Such suction muffler according to the present invention can eliminate the step of pressing to the bonding portions, in the case where a suction muffler constructed with a plurality of resin members is bonded, thus enabling to provide a suction muffler capable of enhancing the reliability of compressor, by preventing production of slag.
The concrete construction of the suction muffler according to the present invention consists in either fitting or putting in contact with each other the bonding portion of a plurality of resin members formed in advance by injection molding. At the same time, the bonding portion is bonded with a resin belt formed with secondary injection molding. Since the bonding of molten resin is made with heat only, this enables to prevent production of slag due to pressing of bonding portions, and to thus provide a suction muffler capable of enhancing the reliability of compressor.
Moreover, the suction muffler according to the present invention has the shape of its bonding face at the fitting portion bent, in the cross section of the bonding portion. Such construction increases the inflow resistance, and this makes it possible to prevent the problem of molten resin flowing into the suction muffler, even in case of inflow of molten resin in the bonding face. This enables to enhance the reliability of compressor.
Furthermore, the suction muffler according to the present invention forms fine projections at the outer circumference of the bonding portion to be bonded by secondary injection molding. A plurality of fine projections provided at the outer circumference of the bonding portion enable to increase the heat receiving surface area on the resin member side. This makes it possible to heat either the fine projections or fine ribs in a comparatively short time, thus enabling to form a suction muffler with bonded resin members. Such construction enables to provide a suction muffler of higher productivity.
Still more, the suction muffler according to the present invention forms a flange which may be realized also by integration in the state in which the contacts of the bonding portion to be bonded by secondary injection molding are in contact with each other. After the bonding, by providing flanges across the bonding face, it becomes possible to engage the resin belt and the resin members formed by secondary injection molding with each other by means of the flanges, in addition to the reactive force applied to the melting portion of the resin belt and the resin members formed by secondary injection molding, even in the case where an outer force is applied in the direction in which the resin members forming the suction muffler are removed. Such construction enables to provide a suction muffler capable of further improving the reliability of compressor.
Yet more, the suction muffler according to the present invention has a tail pipe formed separately inside the suction muffler, and a through hole communicating with the tail pipe at the bonding portion. In addition, the resin members and the tail pipe are combined by means of secondary injection molding. By bonding the tail pipe and the resin members forming the suction muffler at a time, it becomes possible to omit the facilities and working process for bonding the tail pipe, thus enabling to provide an inexpensive suction muffler.
Preferred embodiments of the suction muffler according to the present invention will be described below with reference to drawings.
In
Hollow portion 135 is formed by bonding resin member 105 provided with communicating tube 115 and communicating tube 108, and resin member 120 provided with fastening portion 150 for fixing the position of tail pipe 130 with bonding portion 140.
Explanation will be given below, on the bonding method of a suction muffler constructed as above. Resin member 105 and resin member 120 are fit to each other, after being formed as separate pieces respectively, at bonding portion 143 and bonding portion 146 indicated in
In preferred embodiment 1, the surface of the bonding portion is molten only with the heat of molten resin 160 itself for bonding, and this enables to eliminate the defect of shaking the suction muffler while pressing the bonding portion during the melting. For that reason, it becomes possible to provide a suction muffler capable of enhancing the reliability of compressor, by preventing production of slag in the hollow portion.
Furthermore, since fitting portion 144 is bent about in the shape of the character L, it is possible to prevent inflow of molten resin 160 into the hollow portion, with an increased resistance, even in case molten resin 160 flew into fitting portion 144, thus enabling to provide a suction muffler capable of further enhancing the reliability of compressor.
In addition, because the bonding portion has fine projection 125, the surface area subject to heat from molten resin 160 increases and is heated with the heat of molten resin 160 up to a temperature equal to it in a short time, it becomes possible to form a suction muffler by bonding the resin members to each other, in the state integrated with resin belt 160a accurately, thus enabling to provide a suction muffler with a still higher productivity.
By the way, the section of fitting portion 144 may take the shape of the character U instead of L and, in either case, it provides similar effects if the section is not in a simple linear shape. Although the character U is formed with straight portions and a curve, the shape of the character U as meant in the present invention includes a character U the curved part of which is formed with a straight line or a character U the straight part of which is formed with a curve. Resin member 105 forming cavity 142 and the section formed by resin member 120 may also take a shape other than character U. Moreover, fine projections 107, 125 provided on guide 103 and projection 123 may be fine grooves, and the grooves or fine projections are all right if they are provided in the direction which takes account of the extraction from mold of the members forming the suction muffler.
In
Hollow portion 235 is formed by bonding resin member 205 provided with communicating tube 215 and communicating tube 208, and resin member 220 provided with fastening portion 250 for fixing the position of tail pipe 230 to each other with bonding portion 240.
Firstly, as shown in
After suction muffler 201 is fixed with metallic mold 270, molten resin 260 is injected into cavity 242. Injected molten resin 260 fills cavity 242, and solidifies while melting resin member 205 and resin member 220 together. For that reason, resin member 205 and resin member 220 are bonded integrally simultaneously as resin belt 260a is formed.
In preferred embodiment 2, flange 247 is provided inside cavity 242 in which fitting face 207 and fitting face 229 are interposed. Such construction enables to engage resin belt 260a and resin members 205, 220 formed by secondary injection molding with each other by means of flange 247, in addition to the reactive force applied to the melting portion of resin belt 260a and resin members 205, 220 formed by secondary injection molding. This makes it possible to provide a suction muffler with high bonding strength capable of further improving the reliability of compressor.
Moreover, the shape of contact formed inside cavity 242 may be other than the shape of the character U. Furthermore, even without providing guide 203 and guide 223, it is possible to provide a suction muffler with high bonding strength capable of further improving the reliability of compressor equally, by wrapping flange 247 with the metallic mold and injecting molten rein along bonding portion 240.
Hollow portion 335 is formed by bonding resin member 305 provided with communicating tube 308 and communicating tube 315, and resin member 320 provided with fastening portion 340. Resin member 305 is provided with insert port 302 for inserting tail pipe 330 into communicating tube 315. Bonding portion 343 comprises guide 303, while guide 303 is provided with concavity 385 (see
Resin member 320 is provided with bonding portion 346, and L-shaped guide 323 is provided circumferentially on bonding portion 346. Guide 323 has concavity 390 (see
In the first place, simultaneously as inserting portion 332 of tail pipe 330 is fit into insert port 302 of resin member 305, projection 334 of tail pipe 330 is fit into concavity 385. After the insertion of tail pipe 330, bonding portion 346 of resin member 320 is fit to bonding portion 343 of resin member 305. At the same time, projection 334 is fit by concavity 385 and concavity 390.
After the fitting of resin member 305, resin member 320 and tail pipe 330, concavity 342 is formed with the resin forming metallic mold 370 and bonding portion 340, and part of projection 334 protrudes to the inside of concavity 342.
After suction muffler 301 is fixed with metallic mold 370, molten resin 360 is injected into concavity 342. Injected molten resin 360 melts the resin of resin member 305 and the resin of resin member 320, which form concavity 342. At the same time, the resin of projection 334 of tail pipe 330 protruding to the inside of concavity 342 also melts and solidifies, enabling to bond resin member 305, resin member 320 and tail pipe 330 at a time, simultaneously with the formation of resin belt 360a.
According to preferred embodiment 3, projection 334 of tail pipe 330 is bonded simultaneously as the bonding of resin member 305 and resin member 320, which form hollow portion 335. For that reason, there is no more need of fixing resin member 305 and tail pipe 330 to each other in a separate process. This makes it possible to omit the working process and facilities for simply fixing tail pipe 330, thus enabling to provide an inexpensive suction muffler.
As means for fixing tail pipe 330, resin member 305 and resin member 320, it is all right if only the molten resin is in contact with part of tail pipe 330, even if part of tail pipe 330 does not protrude into the cavity.
As described above, the suction muffler according to the present invention is highly reliable and can be realized at a low cost. For that reason, it can be applied to refrigerator of household use and other articles using refrigeration cycle such as dehumidifier, showcase, vending machine, etc. and has high industrial applicability.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2005-069108 | Mar 2005 | JP | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/JP06/04688 | 3/10/2006 | WO | 10/10/2006 |