EP0610717B1

EP0610717B1 - Washing machine with quick assembly motor

Info

Publication number: EP0610717B1
Application number: EP94101094A
Authority: EP
Inventors: Dino Bongini; Andrea Stopponi
Original assignee: Merloni Elettrodomestici SpA
Current assignee: Whirlpool EMEA SpA
Priority date: 1993-02-08
Filing date: 1994-01-26
Publication date: 1997-09-17
Anticipated expiration: 2014-01-26
Also published as: EP0610717A1; ITTO930069A0; DE69405597T2; ES2110640T3; IT1264052B; DE69405597D1; ITTO930069A1

Description

This invention refer to a washing machine, specifically a laundry washing machine.
It is conventional practice to fasten a motor to the body of a laundry machine having both motor caps provided with supports on which rubber pads are assembled to absorb the vibrations caused by motor during operation; thereafter, spacers will be inserted into the rubber pads to avoid excessive compression when tightening the bolts to fasten the motor to the machine (generally to the tub).
Subsequently the transmission belt is assembled and as a final step belt tension adjusted by positioning the motor correctly, generally using proper slot in the supports.
From DE-A-4 026 549 a washing machine is known, where the motor is sustained by a transmission belt and comprises a rigid guide, which is inserted is a proper seat integral with an appendix of the rear cross member of the washing tub. In this solution, however, vibration and mechanical stresses between the two elements occur, with consequent noise during the machine operation; furthermore, the cited appendix involves a complication in the manufacturing step and reduces the available space within the machine cabinet.
From FR-A-2 201 366 a washing machine is also known where the motor is pivoted at both sides to two supports, being integral with the tub; a spring must be provided, opposing its elastic force to the belt, with the purpose of guaranteeing the belt tension. This solution presents the disadvantage of employing a highly precompressed spring, that complicates to a high extent the motor assembly and disassembly operations, and it is dangerous by itself.
Furthermore, this solution involves a high amount of vibrations being transmitted to the washing tub.
Purpose of the invention is to provide a washing machine, specifically a laundry washer, allowing an easier and faster motor assembly, thus reducing the number of parts required and of operations to be carried out.
Starting from FR-A-2 201 366 these aims are attained by a washing machine and a method for the motor assembly having the characterizing features of the annexed claims 1 and 9.
The features and advantages of the machine according to the invention are detailed in the following description with reference to the annexed drawings, which are supplied only by way of non limiting example, where:

Fig. 1 shows a schematic front view (A) and a side view (B) of the motor for a laundry washer according to the invention;
Fig. 2 shows a schematic front view (A) and a side view (B) of the tub lower section in a laundry washer according to the invention;
Fig. 3 is a schematic view of the motor assembly method of the laundry washer according to the invention;
Fig. 4 is a perspective view of the assembled motor of the laundry washer according to the invention.

In Fig. 1 reference no. 1 refers to the laundry washer motor as a whole according to the invention; no. 2 refers to the rear cap of motor 1, whereas no. 3 shows a support integral to cap 2; said support 3 is used to hook and hold the motor 1 from the rear side through a pin (14 - Fig. 2) fastened to the machine tub.
The support 3 has a shaped section to accommodate a cylindrical rubber pad 4 for motor 1 vibrations absorption.
No. 5 refers to the front cap of motor 1; said cap is provided with two side supports 6.
No. 7 refers to rubber pads inside the side supports 6 for motor stabilisation against static, reverse and operating torques.
The rubber pads 7 are dimensioned and their relevant material selected not only to absorb vibrations but also keep the sheave-motor axle-distance within a range to ensure motion transmission by the belt (15-figs. 3 and 4); said belt is flexible to balance small deviations from the nominal value.
In fig. 2, no. 10 shows the machine tub lower section according to the present invention, e.g. in stainless steel, on which supports 11 and a support 12 for motor 1 are provided; as best seen in the partial section of A in Fig. 2 the supports 11 are shaped and have cylindrical indentations to accommodate the upper part of the rubber pads 7 to hinder motion.
Support 12 has two side brackets 13, between which is located the cylindrical rubber pad 4 through a supporting pin 14 fastened between the two brackets 13.
Fig. 3 illustrates schematically through a step sequence the assembly system on the tub 10 of motor 1; showing in particular the following four steps :

Cycle F1 : motor alignment - during this step the shaped part of support 3 on cap 2 is aligned with the supporting pin 14 bearing the rubber pad 4;
Cycle F2 : motor insertion - during this step the support 3 is hooked through its shaped section onto the rubber pad 4 supported by pin 14;
Cycle F3 : front rubber pads assembly - during this step the rubber pads 7 are assembled in the supports 6 of cap 5; this assembly step is simplified as motor 1 - already supported - can rotate constrained around the pin 14;
Cycle F4 : transmission belt assembly - during this step where final motor positioning is reached, a flexible belt 15 is assembled between the motor and the drum sheave (not shown) of the laundry washer.

Following the above described assembly, the machine motor according to the present invention will appear as shown in Fig. 4.
It should still be mentioned that rotation around pin 14 is constrained to have motor 1 in an easy position during assembly; in other words, the shape of the support 3 upper surface is suitably selected for the motor to be supported with an inclination allowing e.g. an easy assembly of the rubber pads 7 (Fig. 3 - part F3).
According to a further feature the special shape of the support 3 allowing said constrained rotation, practically forms a sort of stop element hindering the motor 1 from falling down and/or striking the floor should the transmission belt 15 break.
According to the above description the features and advantages of the washing machine with simplified motor assembly disclosed by the present invention appear quite evident.
As it results from said description, the washing machine according to the present invention offers the essential advantage of a particularly fast motor assembly and disassembly, without the use of tools.
Obviously, the inventive principle unaffected, many modifications may be made to the constructive features of the machine described by way of example without departing from the innovative criteria of the invention; the same as it is also obvious that in the practical execution of the invention both the shape and dimensions of the components may vary and be replaced by technically equivalent elements.
As an example, in case of wash tubs in plastic material the supports 11 and support 12 may be shaped or moulded.

Claims

Washing machine, specifically a laundry washing machine, comprising a tub and an electric motor (1), said motor (1) being coupled to support means (12) integral with a tub wall (10) and sustained in its front part by a transmission belt (15) extending from the motor (1) to a sheave, whereby rest means (6) are provided between the tub wall (10) and the motor (1) opposing the tension of the belt (15), characterized in that, in order to allow the assembly/disassembly of the motor (1) to the tub without the use of screw, rivets or other equivalent fastening means, or the use of tools:
- said transmission belt (15) is of the flexible type, being able to balance small deviations from its nominal value,

- said motor (1) is hooked only in its rear portion to said support means (12),

- in the contact points between said rest means (6) and the tub wall (10) first rubber pads (7) are provided, for absorbing operating vibrations and keeping the sheave motor axle distance within a range which ensure the motion transmission by the belt.
Washing machine, according to claim 1, characterized in that said support means integral with the tub (10) accommodates a second rubber pad (4), onto which said motor (1) is hooked.
Washing machine, according to claim 1, characterized in that the rear cap (2) of the motor (1) comprises a hook shaped element (3).
Washing machine, according to Claim 1, characterized in that said rest means (6) are integral with the front cap (5) of the motor (1) and define a seat for containing the lower section of said first rubber pads (7).
Washing machine, according to Claim 1, characterized in that resting seats (11) are defined by said tub (10), for containing the upper section of said first rubber pads (7).
Washing machine, according to at least one of the previous claims, characterized in that said resting seats (11) and/or said support means (12) are obtained by the moulding of a tub (10) realized in plastic material.
Washing machine, according to claim 1, characterized in that the hooking system (3,12) between the motor (1) and the support means (12) is shaped for allowing a constrained rotation of said motor (1) around said support means (12).
Washing machine, according to at least one of the previous claims, characterized in that said hook element (3) and/or said support means (12) are shaped for supporting the motor even in case of break of the transmission belt (15).
Method for the assembly of an electric motor (1) to the tub (10) of a laundry washing machine without the use of screw, rivets or other equivalent fastening means, or the use of tools, whereby the motor (1) has to be coupled with support means (12) being integral with said tub (10) and sustained in its front part by a transmission belt (15), rest means (6) being arranged between the tub (10) and the motor (1) opposing the tension of the belt (15), characterized in that the following steps are provided:
- an hooking element (3) integral with the rear part of the motor (1) is aligned with a support means (12) integral with the tub;

- the hooking element (3) is coupled with the support means (12), in a way that the constrained rotation of the motor (1) is allowed around the support means (12);

- the motor (1), while sustained by the support means (12), is rotated around the support means (12) till an inclined position;

- when the motor (1) is in said inclined position, rubber pads (7) are mounted at the ends of the rest means (6);

- the motor (1) is then rotated around said support means (12), till the rubber pads (7) come into contact with the tub wall (10);

- a flexible transmission belt (15) is assembled between the motor (1) and the sheave.