EP2642017A1

EP2642017A1 - Vented laundry dryer

Info

Publication number: EP2642017A1
Application number: EP12160706.3A
Authority: EP
Inventors: Marco Santarossa; Marco Costantin
Original assignee: Electrolux Home Products Corp NV
Current assignee: Electrolux Home Products Corp NV
Priority date: 2012-03-22
Filing date: 2012-03-22
Publication date: 2013-09-25

Abstract

The invention relates to a vented laundry dryer which comprises a casing supporting a revolving drum and having a basement, and an air circulation system, the air circulation system including an inlet duct to intake air from the outside to the drum and a exhaust tube to exhaust the air from the drum to the outside. The exhaust tube is realized in correspondence of the basement and includes a connecting device apt to connect said exhaust tube to an external exhaust tube. The connecting device is realized integral to the exhaust tube.

Description

The present invention relates to a laundry dryer and in particular to a dryer of the vented type, i.e. to those dryer including an exhaust vent passage to allow hot air and water vapor to be exhausted from the dryer to the outside. Known laundry dryers include two categories: condense laundry dryers and vented laundry dryers. Dryers of the first category circulate air exhausted from the drum through a heat exchanger/condenser to cool the air and condense the moisture; they subsequently re-circulate the air back through the drum. Dryers of the second category draw air from the surrounding area, heat it, blow it into the drum during operation and then exhaust it through a vent into the outside.
More in detail, in the vented dryer, the vent passage typically comprises a duct which incorporates a lint trap and which extends from a blower arranged to pull heated air through the dryer drum. A vent tube typically extends from the duct rearwardly to exit at the rear side (or through a sidewall) of the dryer. The vent tube typically exits the dryer through an aperture provided in the rear wall, where it connects to a vent tube extension coupling. The tube is connected to a length of extension tubing that directs the exhaust airflow upward, downward or to the side, external of the dryer, as dictated by the particular installation.
A picture of such a coupling is shown in figs. 1A and 1B where a part of a dryer according to the prior art is shown. The dryer has a removed casing in order to shows the interior. It includes a basement where a vent tube is realized and to this tube a vent tube extension is coupled via a coupling device, which is shown in fig. 1A disconnected from the tubes, while in fig. 1B connected to both the vent tube and the external vent tube extension.
The vent tube extension coupling can be of different forms and shapes. Several patents have been written on this subject in order to provide for improved coupling devices which are easy to connect, fast and secure.
For example, US patent application n. 2005/0184523 discloses a connector for connecting a pair of tubular components together, such as a pair of exhaust conduits of a dryer or an exhaust conduit of a dryer to a dryer vent or wall-mounted vent sleeve, including a pair of generally semi-cylindrical members each having a first, coupled edge and a second, free edge and rotatably connected together at the coupled edge, e.g., by a hinge, and separable from one another at the free edge. A quick connect/quick disconnect locking structure is arranged in connection with the semi-cylindrical members for locking them to one another with the free edges opposite one another.
US patent n. 7603792 describes a dryer hose attachment apparatus, which provides a coupling with more than one embodiment. Each coupling rotationally engages the outlet hose provided for the dryer and the initial hose of a flex hose provided for exhausting air from a dryer environment. Each coupling provides for sealing the dryer exhaust air, from the dryer to the flexible exhaust hose. Each coupling provides for the apparatus to be fitted and to operate in close confines typical to clothes dryer environments. The flange of the dryer attachment may be fixed to the dryer via fasteners. The interior of the outlet hose of the dryer attachment provides sizing for interference fit around an existing hose which exits a dryer. And, both means of engagement may be employed.
US patent n. 5318328 is relative to a quick connect device for coupling a vent or exhaust hose to the exhaust pipe of a clothes dryer or the like, the device having a tubular member of unitary construction with a first, female end portion and a second, male end portion; the first portion including magnetic material for magnetically engaging with an exhaust pipe of dryer, the second portion threadably engaged with an exhaust hose.
Applicant has noted that the presence of such a coupling device between the vent tube of the dryer and the external extension tube is not desired, because it increases the number of structural components forming the dryer, and it is a "weak point" of the dryer structure when it comes to the air tight requirement.
Applicant has therefore implemented a new vented laundry dryer in order to overcome the above mentioned problems, which at the same type provides a quick and reliable connection of the dryer with the external exhaust tube.
Applicants has tackled the problem of how first of all to reduce the number of elements involved in the above described connection without hindering the quality of the same.
According to an aspect of the invention, the vented laundry dryer comprises a casing supporting a revolving drum and having a basement, and an air circulation system, the air circulation system including an inlet duct to intake air from the outside to the drum and a exhaust tube to exhaust the air from the drum to the outside. The exhaust tube is realized in correspondence of the basement and includes a connecting device apt to connect said exhaust tube to an external exhaust tube. The connecting device is realized integral to the exhaust tube.
The connecting device, being realized integral to the exhaust tube, is not an additional element of the dryer, but is realized as a single element together with the tube itself.
The invention may include one or more of the following additional characteristics.
Preferably, the basement and the exhaust tube, including thus the connecting device, are all realized en bloc, i.e. they are a single piece. For example they can be injection molded in a single molding step.
Preferably, the basement and/or the exhaust tube are realized in plastic material, more preferably they are realized in Carboran.
According to a preferred embodiment of the invention, the connecting device includes a thread realized on an end of the exhaust tube, this end is protruding from the casing of the laundry so to be accessible from the outside and being mated to the corresponding female groove of the external exhaust hose.
These and other features and advantages of the invention will better appear from the following description of some exemplary and non-limitative embodiments, to be read with reference to the attached drawings, wherein:

Fig. 1a and Fig. 1b are two pictures of a detail of a vented laundry dryer according to the prior art;
Fig. 2 is a cross-sectional schematic lateral view, where some elements have been removed for clarity, of a vented laundry dryer according to the invention;
Fig. 3 is a perspective view of the laundry dryer of fig. 2;
Fig. 4a and 4b are two cross-sectional lateral view, corresponding to the cross section of fig. 2, of the laundry dryer of fig. 2 and 3 in two different operative conditions;
Fig. 5 is a perspective view of a portion of the laundry dryer of fig. 2;
Fig. 6a and 6b are perspective views of a detail of the laundry dryer of fig. 2 in the operative position of fig. 4b and 4a respectively;
Fig. 7a and 7b show an enlarged detail, in section, of figs. 6a and 6b, respectively;
Fig. 8 is a cross sectional top view of the laundry dryer of fig. 2 and 3;
Fig. 9 and 10 are two perspective view of a detail of the laundry dryer of fig. 2.

With initial reference to fig. 2, a vented laundry dryer according to the present invention is globally indicated with 100.
Laundry dryer 100 comprises an outer box casing 2, preferably but not necessarily parallelepiped-shaped, and a drum 3, for example having the shape of a hollow cylinder, for housing the laundry and in general the clothes and garments to be dried. The drum 3 is preferably rotatably contained into the casing 2, so that it can rotate around a preferably horizontal axis X (in alternative embodiments, not shown, rotation axis may be vertical or tilted). Access to the drum 3 is achieved via a door 4, preferably hinged to casing 2, which can open and close an opening 4a realized on the casing 2 itself. Opening 4a preferably faces drum 3 and it can be sealed by door 4.
Drum 3 defines a lateral surface 3c and two opposite ends 3a,3b, one of which 3a, called front end, includes an opening which faces opening 4a of casing 2, while the second one 3b, opposite to the first and called back end, includes a plurality of through holes (see fig. 3), all indicated with 7, to define a perforated area for the circulation of air, as better detailed below.
With reference to fig. 3, casing 2 generally includes a front panel 20, a rear wall panel 21 and two sidewall panels 22,23 all mounted on a basement 24. Panels 20, 21, 22 and 23 and basement 24 can be of any suitable material. Preferably, the basement 24 is realized in plastic material, more preferably it includes a thermoplastic polymer, such as polypropylene, even more preferably it includes Carboran™. Preferably basement 24 is molded.
In addition, casing 2 includes a plurality of rollers (not visible in the drawings), which are preferably fitted to basement 24, in order to horizontally support in a rotatably manner drum 3 to let revolve the same along its longitudinal axis X.
Laundry dryer 100 also comprises an electrical motor assembly 5 (see fig. 5) for rotating, on command, revolving drum 3 along its axis X inside casing 2 on the rollers. The coupling between the motor assembly 5 and drum 3 can be for example via a belt and a drive pulley (not shown). Preferably, motor 5 is fixed to basement 24.
Casing 2, revolving drum 3, door 4 and motor 5 are common parts in the technical field and are considered to be known, therefore they will not be described in details.
Looking back at fig. 2, dryer 100 additionally includes an air delivery system, schematically depicted in fig. 2 as a plurality of arrows F showing the path flow of the air through the dryer 100. The air delivery system includes a blower (not shown), preferably driven by motor 5, a heater 8 and pathways for directing air along an air path better detailed below (see the arrow of fig. 2). Preferably, the blower is located adjacent to the motor 5 on the basement 24.
Advantageously air enters into dryer 100 through one or more air vents 11 realized in the casing 2, more preferably in the rear panel 21 of same, even more preferably in correspondence to the back end 3b of the drum 3. The air travels through an inlet duct 101 from intake vents 11 reaching the heater 8, where it is heated as it passes through and it is then introduced in the rotatable drum 3 via the through holes 7 located in correspondence to the back end 3b. During operation, the heated air dries the laundry present inside drum 3.
Preferably, heater 8 is located inside casing 2 in the upper-half of drum 3 in correspondence to the rear panel 21.
From holes 7, air passes the whole drum 3 from the back end 3b and it exits the drum 3 from the front end 3a through an exhaust duct 102, preferably including a lint filter 103. Preferably the exhaust duct 102 starts in correspondence of aperture 4a and continues downwardly till it preferably forms a bend. From this bend, air travels through an internal exhaust tube 104 and it is exhausted outside the dryer via an exhaust aperture 105 defining an opening in the casing 2. Exhaust tube 104 extends preferably below drum 3 parallel to the same and to basement 24.
Internal exhaust tube 104 is preferably realized integral to the basement 24. For example, basement and exhaust tube may be molded in the same process step forming an en bloc piece. Preferably, along the exhaust tube 104 also the blower, not illustrated, is located, which creates the vacuum to pull air through the dryer 100.
Although in the depicted drawings exhaust tube 104 exists casing 2 from the rear panel 21, it may exists casing 2 from any of its panels 20, 21, 22, 23 depending on installation and configuration requirements.
Exhaust tube 104, in correspondence to its end 104a protruding outwardly from casing 2 and ending with aperture 105, includes a coupling device 106 realized integral to the tube 104. The coupling device 106 is apt to be connected to an external exhaust hose 107. Preferably, exhaust tube 104 projects from the rear panel 21 of casing 2.
It is to be understood that any conventional external exhaust hose 107 can be securely affixed to the dryer 100 via coupling device 106 according to the present invention. The exhaust hose 107 is generally a flexible hose, for example realized in galvanized steel or copper-plated steel having an outer coating of PolyVinyl Chloride (PVC).
The coupling device 106, which is better shown in figs. 8, 9 and 10, including details of figs. 7A-7B, can be on any type as long as it is realized en bloc with the internal exhaust tube 104, for example it can be molded in the same molding step together with tube 104, even more preferably the whole basement 24 is realized in the same plastic material and even more preferably in the same molding step.
According to the depicted embodiment of the invention, the coupling device 106 includes a threaded portion 19 realized on the end 104a of the exhaust tube 104 which protrudes outside casing 2. More in detail, on a portion of the external surface 104c of the end 104a of exhaust tube 104, in particular on that portion which is accessible from the outside of casing 2, a male external thread is preferably realized.
Accordingly, external exhaust hose 107 includes a female grooving mating the male thread of threaded end 104a.
The cross-sectional shape of the thread 19 may be square, triangular, trapezoidal, or other shapes. The thread is preferably forming at least two complete rotations around the exhaust tube 104 to assure a correct firm coupling with external exhaust hose 107.
Although in the enclosed figures only a connecting device including a thread is depicted, other connecting device may be considered and are included in the present invention, such as a snap fitting connection.
External exhaust hose 107 exhausts the wet air and vapor from dryer 107 and it can have any length and may extend in any direction from the dryer 100 depending on where the air have to be finally discharged.
To realize the connection to the dryer 100, the external exhaust hose 107 is threaded into the male end 104a of the exhaust tube 104, i.e. the end portion 104a of the exhaust tube 104 which includes the connecting device 106. This is depicted in fig. 4A and in figs. 6A and 6B where the two operative positions, connected and disconnected from external exhaust hose, are depicted.

Example

A Carboran basement 24 has been realized, including the exhaust tube 104 and the male threads 19 at its end 104a protruding casing 2, tube and thread all realized integral to the basement.
The tube 104 has an external diameter of 110 mm and the thread 19 has a pitch of 17.7 mm.
External exhaust hose 107 is flexible and has a minimum diameter of 105 mm.

Claims

A vented laundry dryer (100) including a casing (2) supporting a revolving drum (3) and having a basement (24), and an air circulation system, said air circulation system including an inlet duct (101) to intake air from the outside to the drum (3) and a exhaust tube (104) to exhaust the air from the drum (3) to the outside, said exhaust tube (104) being realized in correspondence of said basement (24) and including a connecting device (106) apt to connect said exhaust tube (104) to an external exhaust tube (107), characterized in that said connecting device (106) is realized integral to said exhaust tube (104).
The vented laundry dryer (100) according to claim 1, wherein said exhaust tube (104) is integral to said basement (24).
The vented laundry dryer (100) according to claim 1 or 2, wherein said connecting device (106) includes a thread (19).
The vented laundry dryer (100) according to claim 3, wherein said thread (19) includes a male thread realized on a portion of the outer surface (104c) of an end (104a) of said exhaust tube (104) protruding outside said casing (2).
The vented laundry dryer (100) of any of the preceding claims, wherein said exhaust tube (104) is realized in a plastic material.
The vented laundry dryer (100) according to claim 5, wherein said exhaust tube (104) is realized in Carboran.
The vented laundry dryer (100) according to any of claims 3 or 4, wherein said thread (19) realizes at least two complete rotations around said exhaust tube (104).
The vented laundry dryer (100) according to any of the preceding claims, wherein said basement (24) is located below said drum (3).