GB2190250A - Improvements in or relating to supporting of electric motors - Google Patents

Abstract

A support element for supporting a motor, such as that used to drive the drum of a laundry drying machine, consists of a cradle (19) formed from moulded plastics material provided with two substantially vertical walls (20, 21), an engaging seat (22) on the upper edge of one of the vertical walls (20), for engaging a pin of a motor casing and two corresponding fastening seats (23, 24) formed on the upper edge of each of the walls (20, 21) at the opposite end to the engaging seat (22), each for fastening one of two respective pins of said motor casing, the cradle (19) being provided with relief zones (40, 41, 24) at positions corresponding to said seats for making the coupling between the motor and the support resilient. The three point mounting permits automatic assembly and defines motor orientation. <IMAGE>

Description

SPECIFICATION Improvements in or relating to supporting of electric motors This invention relates to a support element for supporting and fixing an electric motor such as for driving of the drum in a laundry drying machine.

In that type of machine, the electric motor is generally mounted on a metal support cradle which in turn is fixed to the base of the casing, and transmits the rotary movement both to the drum and to the fan for the drying air circuit, by means of conventional belt-pulley systems.

In addition, the motor is frequently designed to take part in tensioning of the transmission belt; for that purpose, it is mounted with the capability of oscillating on the support cradle and a resilient belt tensioner is connected to the external shield or casing portion thereof.

That construction requires a particular configuration in respect of the end flanges of the drive shaft of the motor and the use of damping ring members of rubber and associated fixing elements (such as bushes, screws or spring clips). A more rational design is proposed in British patent application No.

8628381 filed on 27th November 1986 claiming a fixing arrangement produced with a component which is moulded of plastics material and provided both with vibration damping elements and with elements for positioning and engagement with the metal support cradle of the motor. That construction produces a reduction in the number of components employed and associated assembly operations, but it still suffers from the limitation of the metal cradle which needs to be produced with a high degree of accuracy to permit mounting and operation without disadvantages.

In accordance with the invention there is provided a support element for supporting and fixing a motor of a washing or laundry drying machine comprising a cradle in which there is provided at least one engagement seat and two fastening seats for respective pins projecting from the casing portions of the motor, the cradle being provided with relief zones at positions corresponding to said seats for making the coupling between the motor and the support resilient.

As will become apparent from the following description the invention can provide an arrangement which combines in one piece both the support elements and the fixing elements of the motor, permitting automated mounting and maintaining the accuracy and functionality of the motor-support assembly.

In order that the invention may be more easily understood the following description is given by way of non-limiting example with reference to the accompanying drawings in which: Figure 1 is a diagrammatic side view of a motor mounted on the arrangement according to the invention, and Figure 2 is a perspective view of the support arrangement according to the invention.

Fig. 1 shows a motor 10 of a known type for producing the rotary movement of the drum of a laundry drying machine (not shown) and for actuating at the same time the fan which circulates the drying air through the drum.

The motor 10 is provided with a shaft 11 and two lateral end case portions 12 (only one is visible in Fig. 1).

An end of a lever 14 of a belt tensioner (not shown) is pivoted on the casing portion 12 shown in Fig. 1, at the pin 13. The other end of the lever 14 is connected to a peg 15 on the casing portion 12 by means of a spring 16.

The casing portion 12 is also provided with two pins 17 and 18 for supporting and fixing the motor 10 to a cradle 19 which is normally mounted in the casing of the laundry drying machine.

The casing portion 12 (not visible) at the opposite end of the motor is on the other hand preferably provided with a single pin corresponding to the pin 18 of the casing portion which can be seen in Fig. 1.

The cradle 19 of which a perspective view is shown in Fig. 2 is formed as a single moulded component of plastics material (for example glassfibre reinforced polyamide) and is provided with elements for supporting and fixing the motor. The cradle 19 is the general form of a "U" and has two substantially vertical walls 20 and 21, on the upper free edge of which are provided at least one engagement seat 22 and two coupling or hooking seats 23 and 24 for the pins 17 and 18 of the casing portions 12.

More precisely, on one side, the wall 20 is provided with a vertical projection 25 from which projects a tooth 26 which is slightly inclined downwards towards the edge of the wall 20, in such a way as to provide the engagement seat 22. Preferably, provided on the edge of the wall 20 in the seat 22 is a tooth 30 for positioning and arresting the pin 17 on the motor and for subsequently contributing to damping of the vibrations of the motor during operation thereof. Fastening seats 23, 24 are each provided on the respective end walls at a position corresponding to a projection portion connected by means on an inclined and curved edge to a resilient tooth 29 which is bent in a hook configuration.

The seat 24 provided on the wall 21 precisely corresponds to the seat 23 on the wall 20, as is clearly shown in Fig. 2. On the other hand the wall 21 does not have any engagement seat corresponding to the seat 22 on the wall 20 to permit automated mounting of the motor 10 on the cradle 19, in order that the pins 17 and 18 and the pin at the other end of the motor corresponding to the pin 18 lie in a single plane, in any operating condition. As is known, three non-aligned points define a single plane.

Mounting of the motor 10 in the cradle 19 is thus very easy and convenient. It is only necessary to position the pin 17 on the respective edge of the walls 20 and to slide it in such a way that pin 17 is engaged into the engagement seat 22 and abuts against the projection portion 25; the motor 10 is then rotated about pin 17 and the pins 18 are inserted into the respective seats 23 and 24 where they are held in position by the resilient teeth 29.

The final position can be seen fom Fig. 1.

The function of damping vibrations during operation of the motor is effected by suitable relief zones provided by apertures 40, 41 and 42 provided in the walls 20 and 21 at positions corresponding to the seats 22, 23 and 24 (Figs. 1 and 2). Those apertures are produced directly in the moulding of the cradle 19 and the shapes and dimensions thereof may be selected experimentally on the basis of the characteristics of the motor 10 (in particular the weight and the speed of rotation thereof), the material of the cradle 19 and the forces due to the belt tensioning arrangement 14-16.

Finally the cradle 19 may advantageously be provided with stiffening and reinforcing ribs, in particular at positions corresponding to the edges of the walls 20 and 21, in accordance with the normal procedre for moulding plastics materials.

Claims (8)

1. A support element for supporting and fixing a motor of a washing or laundry drying machine comprising a cradle in which there is provided at least one engagement seat and two fastening seats for respective pins projecting from the casing portions of the motor, the cradle being provided with relief zones at positions corresponding to said seats for making the coupling between the motor and the support resilient.

2. A support element according to claim 1 wherein said cradle is provided with two end walls substantially perpendicular to an intermediate wall connecting them, one end wall being provided with an engagement seat and a fastening seat while the other end wall is provided with only one such seat, the seat being a fastening seat, said fastening seats being disposed towards corresponding side of the respective end walls.

3. A support element according to claim 2 wherein the engagement seat is formed on the upper edge of the respective wall there being a tooth projecting from a substantially vertical projection portion of the end wall and slightly inclined towards the edge thereof.

4. A support element according to claim 2 or 3 wherein each fastening seat is provided on the respective end wall at a position corresponding to a projection portion connected by means of an inclined and curved edge to a resilient tooth which is bent in a hook configuration.

5. A support element according to any preceding claim wherein said cradle is made from a single moulded piece of plastics material.

6. A support element according to any one of the preceding claims wherein the relief zones are provided by apertures through the material of the cradle.

7. A support element suitable for supporting a motor, said apparatus being substantially as hereinbefore described with reference to the accompanying drawings.

8. A machine for drying laundry having a motor support element according to any one of the preceding claims.