EP0108976B1

EP0108976B1 - Laundry dryer with rotatable drum

Info

Publication number: EP0108976B1
Application number: EP83110763A
Authority: EP
Inventors: Franco Del Frate
Original assignee: Industrie Zanussi SpA
Priority date: 1982-11-11
Filing date: 1983-10-27
Publication date: 1988-07-06
Also published as: ATE35561T1; IT8234045V0; EP0108976A2; DE3377289D1; EP0108976A3

Abstract

The invention relates to a laundry dryer comprising a drum rotatably mounted in an outer housing. The drum is formed of a cylindrical side wall and a pair of rear and front end walls, respectively. The rear end wall carries an axle stub mounted in a rear support for free axially sliding movement. The frant end wall has a projecting circular rim portion engaged over a circular front support element provided with means exerting an axial compressive force on the drum for keeping the axle stub engaged with its support and preventing axial displacement of the drum during its rotation. This construction permits the drum to be mounted and dismounted directly from in front of the machine without necessitating access from the rear.

Description

The present invention relates to a laundry dryer provided with a rotatable drum adapted to be simply and reliably mounted therein.
As generally known, conventional laundry dryers are provided with a rotatable drum adapted to contain the laundry to be dried and mounted in an exterior housing, said drum being traversed by a stream of drying air generated by at least one blower or fan and heated by means of suitable heater elements.
The drum itself is formed of a cylindrical side wall and two end walls, a front end wall and a rear end wall, respectively, both of which may be supported by the frame of the machine.
In particular, the rear end wall is provided with a central stub axle cooperating with a suitable support, e.g. a bushing or roller bearing carried by the frame of the machine, while the front end wall is formed with a projecting circular rim portion cooperating with a complementary circular support located in the forward portion of the housing.
For mounting the drum in the housing, the stub axle carried by the rear end wall is first introduced into its support and secured in position by means of conventional fastening means preventing the stub axle from being withdrawn from the support. Subsequently the projecting circular rim portion of the front end wall is inserted over the above defined circular support which to this effect is provided with slide elements of a suitable low-friction material, with the interposition of a seal formed of felt or another low-friction material for preventing the escape to the exterior of the heated air circulating in the drum.
In this manner the drum is freely rotatable without the possibility of axial displacement. For maintenance, repairs, exchange of defective parts and similar operations, the drum can be dismounted after releasing the described fastener elements at the rear of the housing of the machine.
In laundry dryers of conventional design, dismounting of the drum in the described manner is thus only possible if the machine is installed so that its rear side is readily accessible. If to the contrary a machine of this type is installed in a limited space, as for instance in the case of a furniture combination, dismounting of the drum becomes very difficult and requires extremely cumbersome operations.
It is therefore an object of the present invention to eliminate the above discussed difficulties by providing a laundry dryer having a rotatable drum adapted to be dismounted in a simple manner by operating solely from the forward portion of the machine. As in conventional designs, the drum is also in this case supported in the housing of the machine at its front and rear end walls without the possibility of axial displacement during rotation. These and other objects are attained according to the invention by a laundry dryer comprising an outer housing and a rotatable drum adapted to contain the laundry to be dryed and formed of a cylindrical side wall and two end walls, e.g. a rear end wall and a front end wall, respectively, said end walls being supported respectively in said housing by means of a central stub axle cooperating with a corresponding support and by a projecting circular rim portion cooperating with a corresponding circular support element provided with slide tabs, with the interposition of a sealing element formed of a low-friction material. According to the invention, a laundry dryer of this type is characterized in that said central stub axle is supported in said rear support in a freely slidable manner in the axial direction, and in that said forward support element is provided with resiliently movable means adapted to exert an axial compressive force on said drum so as to constantly keep said axle stub engaged with said rear support and to prevent axial displacement of said drum.
The characteristics and advantages of the invention will become more clearly evident from the following description, solely by way of example, of a preferred embodiment with reference to the accompanying drawings, wherein:

fig. 1 shows a diagrammatical side view of a laundry dryer according to the invention, and
fig. 2 shows a cross-sectional side view on an enlarged scale of a detail of the machine shown in fig. 1.

With reference to fig. 1, the laundry dryer according to the invention substantially comprises an outer housing 3 and a drum 4 adapted to contain the laundry to be dried and to be rotated about its horizontal axis by means of an electric motor (not shown).
Drum 4 is formed of a cylindrical side wall 5 and two end walls 6 and 7, a rear end wall and a front end wall, respectively, adapted to support said drum within said housing in a manner to be described.
The rear portion of housing 3 is formed by a rear wall 8 formed with air inlet openings 9 for the aspiration of air which is conveyed to the interior of drum 4 through an inlet duct 10 communicating with the interior of drum 4 through perforations in rear end wall 6 and containing at least one electric heater element 11. The dryer further comprises a front opening 12 closed by a door 13 giving access to the interior of drum 4 and provided with a perforated interior wall 14.
The heated air is exhausted from the interior of drum 4 through perforated wall 14 and conveyed to an outlet opening 15 along a further conduit 16 containing a motorized fan 17.
Conduit 16 is further provided with a conventional filter 18 inserted into a conduit inlet opening 19 and adapted to retain any lint released by the laundry and other foreign materials possibly entrained by the air stream.
Rear end wall 6 of drum 4 is provided with a central axle stub 20 formed integrally therewith or rigidly attached thereto, said axle stub being adapted to by axially inserted into a conventional support 21 provided for instance with a bushing 22 of a low-friction material disposed in a suitable seat 23 formed in the rear wall 8 of the machine. In addition, an elastic seal 24 of a low-friction material is disposed between rear end wall 6 and the housing of the machine for preventing the escape of heated air from the interior of drum 4. The front end wall 7 of drum 4 is formed with a projecting circular rim portion 25 dimensioned for insertion over a circular support element 26 attached to a front wall 27 of the housing opposite front end wall 7 of drum 4.
As shown in fig. 2, support element 26 is formed of a circular array of individual support members each comprising a "C" profile section 28, an inclined web section 29 and an inverted "C" profile section 30.
Located between a flat portion of first "C" profile section 28 and circular rim portion 25 of drum 4 are slide elements 31 formed of a low-friction material for sliding contact with circular rim portion 25 during rotation of drum 4.
For providing a sliding seal arrangement between drum 4 and support element 26 and for thus preventing the escape of the heated air from the interior of drum 4, the inclined web portion 29 of support element 26 is provided with a resilient seal 33 itself supporting a felt ring 34 for sliding contact with circular rim portion 25.
The inverted "C" profile section 30 of support element 26 serves as a seat for a plurality of slidingly movable abutment members 35 uniformly spaced about the periphery thereof and each biased by an associated compression spring 36 into axial abutment with circular rim portion 25.
Each abutment member 35 is formed with a projection 37 adapted to engage a stop 38 formed in "C" profile section 30 for preventing the abutment member from escaping from its respective seat. The abutment members are formed of a low-friction material and are kept in sliding contact with circular rim portion 25 of drum 4 during rotation thereof.
The described construction permits the drum to be mounted in -the housing of the machine directly from in front thereof by simply inserting axle stub 20 of rear end wall 6 into its support 21. In this embodiment, axle stub 20 is not fixed in position as in conventional constructions, but is retained in support 21 in a freely movable manner.
Subsequently support element 26 is mounted opposite front end wall 7 so that its abutment members 35 axially abut circular rim portion 25 of drum 4. The abutment members 35 are biased by their respective springs 36 into abutment with the circular rim portion 25 so as to exert an axial compressive force on the drum for keeping axle stub 20 engaged with its support 21.
This action of the abutment members is directed opposite to that of the above mentioned resilient seal 24, resulting in constant accurate centering of the drum and preventing axial displacement thereof.
In this manner, the operation of mounting the drum in the laundry dryer according to the invention is considerably facilitated by comparison to similar operations on existing laundry driers. In addition, the drum can be readily dismounted for maintenance, repairs and the like by operating directly from in front of the machine after removal of the forward support element. This is of particular advantage in a case in which the laundry dryer is installed in a limited space, for instance as part of a furniture combination.

Claims

1. A laundry dryer comprising an outer housing (3) and a rotatable drum (4) adapted to contain the laundry to be dried and formed of cylindrical side wall (5) and two end walls, a rear end wall (6) and a front end wall (7) respectively, said end walls being supported within said housing (3) by means of a central axle stub (20) cooperating with a corresponding support (21), and by projecting circular rim portion (25), respectively, cooperating with a corresponding circular support element (26) provided with slide tabs, with the interposition of a sealing element formed of a low-friction material, characterized in that said central axle stub (20) is supported in said rear support (21) so as to be freely slidable in the axial direction, and in that said front support element (26) is provided with resiliently movable means (35) adapted to exert an axial compressive force on said drum (4) so as to constantly keep said axial stub (20) engaged with said rear support (21) and to prevent axial displacement of said drum (4).

2. A laundry dryer according to claim 1, characterized in that said resiliently movable means comprise a number of sliding abutment members (35) seated in said front support element (26) and uniformly distributed about the periphery thereof, each said abutment member (35) being biased by an associated compression spring (36) in the direction towards said circular rim portion (25) provided with a projection (37) adapted to be brought into engagement with an associated stop (38) of said support element (26).