Dryer-ironer with heated ironing cup and heat carrying fluid

Information

  • Patent Grant
  • 6360460
  • Patent Number
    6,360,460
  • Date Filed
    Thursday, February 22, 2001
    23 years ago
  • Date Issued
    Tuesday, March 26, 2002
    22 years ago
Abstract
Dryer-ironer with heated ironing cup and heat-carrying fluid.In a dryer-ironer with heated cup (10), the cup is built so as to define a closed chamber (26) containing a heat carrying fluid between two parallel walls (18, 22). The fluid is set into motion through a stirring system integrated with the cup so as to provide the establishment of a uniform temperature along its entire length.
Description




DESCRIPTION




1. Technical Field




The present invention relates to a dryer-ironer wherein the laundry is ironed between a heated ironing cup and a rotating roller.




The dryer-ironer according to the invention may be used in all cases where relatively large amounts of laundry must be frequently ironed. Thus and uniquely as an example, such a machine may be used in hospital institutions, nursing homes, lodging houses, hotels, restaurants, etc.




2. State of the Art




In dryers-ironers with a cup, ironing of the laundry is performed between a metal ironing cup, in the shape of a cylindrical sector with a generally horizontal axis, and a pressing roller covered with baize, the axis of which coincides with that of the cup and the lower portion of which rests on said cup. When the machine is operating, the pressing roller is driven into rotation around its axis. Consequently, the pieces of laundry to be ironed, inserted between the cup and the roller on one side of the machine, come out on the other side.




For ironing of laundry to be carried out in the best possible conditions, the ironing cup is provided with heating means. Depending on the machines, these heating means may either be totally integrated into the machine, or else placed outside the latter.




When the heating means of the ironing cup are integrated into the dryer-ironer, they may be of different types, depending on the machines. Hence, these heating means may notably consist of gas manifolds, electric resistances, infrared heating devices, etc.




Machines of this type provide the advantage of being simple and not very expensive and of having excellent cost effectiveness.




On the other hand, they have the drawback that the cup is uniformly heated on its entire length, regardless of the areas where the pieces of laundry are inserted during ironing. Consequently, after ironing a piece of laundry in a given area of the ironing cup, this area is at a lower temperature than the value required for the ironing, whereas the other areas of the cup, which continue to be heated, are on the contrary at a higher temperature than this value. Consequently, the next piece of laundry will be badly ironed if it is inserted in the same area as the previous one or be burnt if it is inserted in a different area. Actually, the thermal gradient even increases if several pieces of laundry are successively inserted substantially in the same area.




Dryers-ironers wherein the ironing cup is heated by means located outside the machine, use a heat carrying fluid. This heat carrying fluid is heated in a boiler located outside the machine, before being fed into the cup by a pump also placed outside the machine.




Contrary to dryers-ironers wherein the heating means of the cup are integrated into the machine, dryers-ironers with a heat carrying fluid are able to provide good heat diffusion on the entire length of the cup, regardless of the areas into which are inserted the pieces of laundry.




On the other hand, these machines have the drawbacks of requiring heavy, expensive and complex external facilities.




When several dryers-ironers are placed in a same building, these drawbacks sometimes result in that the users feed these machines with heat carrying fluid simultaneously, from a unique circuit integrating a single boiler and a single pump. However, such facilities are only feasible if several dryers-ironers are used simultaneously and they remain more expensive and more complex than facilities using machines with integrated heating.




DESCRIPTION OF THE INVENTION




Specifically, the object of the invention is a dryer-ironer with heated cup, its original design allows it to benefit both from cost effectiveness and cost advantages specific to machines with integrated heating and from the advantages provided by uniform diffusion of heat on the entire length of the cup of machines which are heated through a heat carrying fluid.




According to the invention, this result is obtained by means of a dryer-ironer comprising an ironing cup in the shape of a cylindrical sector provided with an internal wall, able to come into contact with the laundry to be ironed, and means for heating said wall, characterized in that the cup further comprises an external wall which externally lines, at a distance, the internal wall, directly close to the heating means, so as to delimit with said internal wall, a closed chamber filled with a heat carrying fluid able to transfer heat produced by heating means to the internal wall, and stirring means able to generate a circulation of heat carrying fluid within said chamber.




The machine according to the invention has integrated heating means. It thus benefits from economical advantages and from the excellent cost effectiveness both specific to this type of machine.




On the other hand, the use of a heat carrying fluid put into circulation by stirring means also integrated into the machine, provides effective diffusion of heat over the entire length of the ironing cup, as in machines using an external boiler.




In a preferred embodiment of the invention, the stirring means comprise partitions positioned in a staggered configuration within the closed chamber, in order to delimit between the internal and external walls, a path for reciprocating motion, substantially parallel to an axis of the cylindrical sector formed by the cup. The stirring means also comprise driving means such as a pump in order to cause the heat carrying fluid to circulate along this path.




The heating means, which may assume any shape as in existing machines with integrated heating, are advantageously placed outside the closed chamber.




Moreover, the internal wall of the cup is advantageously made of stainless steel and the external wall of ordinary steel.











BRIEF DESCRIPTION OF THE DRAWINGS




A preferred embodiment of the invention will now be described as a non-limiting example, with reference to the appended drawings, wherein:





FIG. 1

is a sectional view which very schematically illustrates a dryer-ironer according to the invention;





FIG. 2

is a sectional view, which schematically illustrates at a larger scale the ironing cup of the machine of FIG.


1


and the associated heating means; and





FIG. 3

is a perspective view with partial cutout, illustrating the ironing cup.











DETAILED DESCRIPTION OF A REFERRED EMBODIMENT




As illustrated in

FIG. 1

very schematically, the dryer-ironer according to the invention primarily comprises an ironing cup


10


and a roller


12


covered with baize. This type of machine is well known to one skilled in the art, so that only the features required for a good understanding of the invention will be described.




The ironing cup


10


is mounted on a fixed chassis (not shown). It is made of a metal such as stainless steel and has, according to the invention, a particular structure which will be described later on. Generally, the ironing cup


10


assumes the shape of a cylindrical sector, the axis of which


14


is substantially horizontal and the recessed portion of which is turned upwards.




Roller


12


appears with the shape of a hollow cylinder, the external peripheral surface of which is covered with baize. Roller


12


is coaxially mounted on cup


10


. It is supported by the chassis of the machine, so that it may rotate around axis


14


. A geared motor (not shown) enables the roller


12


to rotate about axis


14


in the direction of the arrows in FIG.


1


. In addition, elastic means (not shown) interposed between the chassis and cup


10


, apply the latter against the lower portion of cylinder


12


.




In the dryers-ironers of this type, the pieces of laundry to be ironed are inserted one after the other on one side of the machine (on the left in

FIG. 1

) between cup


10


and roller


12


, each piece of laundry comes out of the machine, ironed, on the opposite side (on the right in FIG.


1


).




As illustrated schematically in

FIG. 1

, the dryer-ironer according to the invention also comprises means


16


for heating the ironing cup


10


, integrated into the machine. These heating means


16


may comprise any heating means usually used on dryers-ironers with integrated heating cups. Thus, and uniquely as an example, these may be gas manifolds, electric resistances, infrared devices, etc.




As further illustrated in detail in

FIG. 2

, the ironing cup


10


comprises, according to the invention, two parallel walls, at a distance from one another so as to delimit between each other a closed chamber of substantially uniform thickness.




More specifically, cup


10


comprises an internal wall


18


, in the shape of a cylindrical sector, preferably made of stainless steel. The internal surface


20


of internal wall


18


is a smooth surface which comes directly into contact with the laundry to be ironed. This wall


18


is preferably relatively thin. As an absolutely non-limiting illustration, internal wall


18


may have a thickness between 1.5 mm and 2 mm, depending on the size of the machine.




The ironing cup


10


also comprises an external wall


22


which lines the internal wall


18


, on the side of its convex lower face, at a distance from the latter. The substantially uniform distance separating walls


18


and


22


may for example, be about 5 mm. The external wall


22


is made of metal such as ordinary steel, it is substantially thicker than the internal wall


18


. Thus, the thickness of the external wall varies, for example, between 4 mm and 6 mm, depending on the size on the machine.




The internal wall


18


is fixed on the upper face of the external wall


2


through two rectilinear shims


24




a


positioned along the longitudinal edges of both walls and of both shims in a circular arc


24




b


(

FIG. 3

) positioned along the curved edges of both walls. Shims


24




a


and


24




b


may notably be welded onto the upper face of external wall


22


, after which, the edges of internal wall


18


are themselves welded onto shims


24




a


,


24




b


.




A closed chamber


26


, sealed relatively to the outside world is thereby delimited between walls


18


and


22


. This chamber


26


is at least partly filled with a heat carrying fluid. This heat carrying fluid may comprise any fluid usually used in dryers-ironers, the cup of which is heated by a heat carrying fluid. This fluid is, for example and in a non-limiting way, a liquid such as oil. In order to take into account thermal expansions of the heat carrying fluid contained in chamber


26


, the latter may be connected with an expansion vessel (not shown) also integrated into the machine.




As illustrated schematically in

FIG. 2

, heating means


16


are placed outside cup


10


, below the latter and directly close to wall


22


. Therefore, heating means


16


directly heat the thick external wall


22


of the cup. Heat is then transferred to the internal thin wall


18


by the heat carrying fluid contained in chamber


26


.




For the heat to uniformly diffuse over the internal face


20


of wall


18


, during ironing, the dryer-ironer according to the invention further comprises stirring means also integrated into the machine. These stirring means are laid out so as to generate a circulation of heat carrying fluid within chamber


26


, both in parallel to axis


14


of the cup, in order to homogenize the temperature, and between walls


22


and


18


, in order to transfer heat released by heating means


16


to the internal wall


18


. An embodiment of stirring means will now be described as an example with reference to FIG.


3


.




In this figure, it is seen that the stirring means comprise both partitions positioned in chamber


26


and driving means


30


, such as a pump in order to cause the heat carrying fluid to circulate along a path delimited by the partitions.




More specifically, the aforementioned partitions comprise a partition in a circular arc


28




a


, which extends close to one of the shims in a circular arc


24




b


, parallel to the latter, so as to delimit with the latter, a channel


32


in a circular arc. This channel


32


is divided into two portions of the same length by a partition


28




b


, with a parallel orientation with respect to the axis


14


of the cylindrical sector formed by the cup. The aforementioned partitions further comprise a series of rectilinear partitions


28




c,


with a parallel orientation one with respect to another, along axis


14


of the cylindrical sector formed by the cup. These rectilinear partitions


28




c


are regularly distributed between the two rectilinear shims


24




a


, so as to delimit between each other and with the latter, rectilinear channels


34


. One out of two of the rectilinear partitions


28




c


is connected to the partition in a circular arc


28




a


and is interrupted at a certain distance from the shim in a circular arc


24




b


, the furthest one from this partition


28




a


. The other rectilinear partitions


28




c


are connected to this last shim in a circular arc


24




b


and interrupted at a certain distance from the partition in a circular arc


28




a


. In addition, among the rectilinear partitions


28




c


connected to the partition in a circular arc


28




a


, two partitions


28




c


are found, the closest to the rectilinear shims


24




a


, and the partition in a circular arc


28




a


is interrupted between both of these partitions


28




c


and shims


24




a


. Consequently both portions of the channel in a circular arc


32


separated by partition


28




b


communicate with both rectilinear channels


34


adjacent to rectilinear shims


24




a


, respectively.




A path for reciprocating motion is thus delimited between walls


18


and


22


, with a parallel orientation with respect to axis


14


of the cylindrical sector formed by the cup.




Pump


30


is connected to each of both portions of channel


32


, on both sides of partition


28




b


, through suction piping


36


and discharge piping


38


respectively




When pump


30


is actuated, circulation of the hydraulic fluid is thus generated in chamber


26


, along the path illustrated by arrows in FIG.


3


. This path, delimited by partitions


28




a


,


28




b


and


28




c


, is mainly characterized by a reciprocating movement of the fluid, parallel to axis


14


of the cylindrical sector formed by cup


10


, virtually over the entire length of the latter.




It should be noted that partitions


28




a


,


28




b


and


28




c


preferably have a height substantially equal to that of shims


24




a


,


24




b


, i.e. substantially equal to the thickness of chamber


26


. With this layout, any circulation of the heat carrying fluid other than the one imposed by the partitions may be prevented. With this layout, partitions


28




a


,


28




b


, and


28




c


may also serve as a support for the internal wall


18


, which is relatively thin. The cylindrical geometry of the internal surface


20


of wall


18


is thus maintained in spite of the relative thin thickness of this wall.




Thanks to the characteristics which have just been described, the dryer-ironer according to the invention may guarantee excellent ironing quality because heat is uniformly diffused over the entire surface of the cup through the heat carrying fluid in motion.




Furthermore, the machine according to the invention is a simple machine and of a relatively limited cost, because it does not require the use of an external boiler.




Of course, the invention is not limited to the embodiment which has just been described as an example. Hence, the stirring means with which the cooling fluid may be forced to circulate in chamber


26


, may be different from the described means. The same applies to the relative thicknesses for connecting these walls one to another by delimiting a closed chamber between them. Notably it is conceivable that the partitions are made of an embossed thin metal sheet, placed between partitions


18


and


22


.



Claims
  • 1. Dryer-ironer comprising an ironing cup in the shape of a cylindrical sector provided with an internal wall able to come into contact with the laundry to be ironed, and means for heating said wall, characterized in that the cup further comprises an external wall which externally lines, at a distance, the internal wall directly close to the heating means, so as to delimit with said internal wall a closed chamber filled with a heat carrying fluid able to transfer to the internal wall heat produced by the heating means, and stirring means able to generate a circulation of heat carrying fluid within said chamber;wherein said stirring means comprise partitions in a staggered configuration in the closed chamber, in order to delimit between the internal and external walls, a path for reciprocating motion, substantially parallel to an axis of said cylindrical sector, and driving means for causing the heat carrying fluid to circulate along said path; wherein said partitions have a height substantially equal to the thickness of the closed chamber, such that they serve as a support for the internal wall.
  • 2. A dryer-ironer according to claim 1, wherein the heating means are placed outside the closed chamber.
  • 3. A dryer-ironer according to claim 1, wherein the internal wall is made of stainless steel and the external wall of ordinary steel.
  • 4. Dryer-ironer comprising an ironing cup in the shape of a cylindrical sector provided with an internal wall able to come into contact with the laundry to be ironed, and means for heating said wall, characterized in that the cup further comprises an external wall which externally lines, at a distance, the internal wall directly close to the heating means, so as to delimit with said internal wall a closed chamber filled with a heat carrying fluid able to transfer to the internal wall heat produced by the heating means, and stirring means able to generate a circulation of heat carrying fluid within said chamber, wherein the external wall is substantially thicker than the internal wall.
Priority Claims (1)
Number Date Country Kind
00 02232 Feb 2000 FR
US Referenced Citations (2)
Number Name Date Kind
4418486 Kober Dec 1983 A
5022169 Jensen Jun 1991 A
Foreign Referenced Citations (6)
Number Date Country
1 009 978 Nov 1997 BE
860 940 Dec 1952 DE
1280802 Jun 1961 DE
0 332 840 Sep 1989 EP
1 135 197 Apr 1957 FR
1 332 810 Dec 1963 FR