GB2027139A

GB2027139A - Expanding-wheel Gearing, Particularly for Washing Machines

Info

Publication number: GB2027139A
Application number: GB7926693A
Authority: GB
Original assignee: Candy SpA
Current assignee: Candy SpA
Priority date: 1978-08-01
Filing date: 1979-07-31
Publication date: 1980-02-13
Also published as: GB2027139B; FR2432572A1; FR2432572B3; IT7826383A0; DE2931067A1; IT1097559B

Abstract

Expanding-wheel gearing for driving the basket 9 of a washing machine comprises two varying diameter pulleys 1, 2, respectively a driving one and a driven one, this latter being applied to the basket shaft 12, said driving pulley 1 being formed by two half pulleys, one 3 thereof being rigid with a driving shaft 5, while the other 4 is able of sliding along the axis of said driving shaft; to said movable half pulley 4 being furthermore applied centrifugal masses 6, said masses being housed between said movable half pulley and a disk element 8. Centrifugal masses may also be provided between the half pulleys 10, 11 of the driven pulley 2. Means such as an electromagnetic device may be employed to selectively prevent movement of the centrifugal masses 6. <IMAGE>

Description

SPECIFICATION An improved Device For Transmitting Movement, Effective To Be Applied To Washing Machines The present invention relates to an improved device for transmitting movement effective to be applied to washing machines.

As it is known, the different basket rotation speeds, during the washing and centrifuging operations, are nowadays transmitted by different systems.

These latter provide for the possibility of using a multiple pole motor or a single or double pole motor, to which a mechanic change-speed gear is to be added.

Alternately is is possible to use a c.c. electric motor.

Said devices effective to move the basket with suitable speeds have the characteristic that they permit to have a fixed transmission ratiow p basket pulley/sAp motor pulley=K).

The device according to the present invention differentiates from the conventional ones in that it permits to ful!y exploit the transmission predetermined ratios and, in addition, it permits to have a diameter variation on the basket pulley, with the possibility of recovering the belt length, as the transmission ratio varies.

This characteristic prevents the transmission belt from being subjected to dangerous overloads et permits to use a conventional type of large series belt.

The device according to the present invention provides for the use of two varying diameter pulleys, one thereof is connected to the motor or driving shaft, while the other is fixed to the basket of a washing machine.

The first of said pulleys, in turn, is formed by two half pulley, one thereof being rigid with the -driving shaft and the other being able of sliding along the axis of said driving shaft.

The movable half pulley has applied or fixed expandible masses, which, as the polarity of the motor is changed, allow for said half pulley to axially move and accordingly cause a diameter variation of the related pulley.

The basket driven pulley is also formed by two half pulleys, one thereof being fixed, while the other is able of moving on the basket shaft.

The device is furthermore provided with a spring maintaining in a pressed condition said two half pulley with such a force as to not permit said movable half pulley to move due to the belt pulling action and the motor working couple.

The contour of the groove of the two pulleys (driving and driven pulleys) has been studied in such a way as to permit a good variation of the belt diameter on the pulley to be obtained, with a minimum axial shifting of said movable half pulley.

Owing to these characteristics, as the motor operates with low polarity, that is it operates with a low revolution number, the instant device operates like the conventional mechanic devices as applied to the conventional washing machines.

Under these operation conditions, the mass centrifugal force, which masses are located on the driving pulley, is cancelled by the force of the spring applied to the basket pulley.

By supplying the motor with high polarity (that is as said motor rotates at a high revolution number)-owing to the centrifugal effect of the masses of the driving pulley, this latter changes the diameter thereof in such a way as to increase said diameter, and accordingly causing said driven pulley to decrease its diameter.

Thus the extension and the pulling action of said belt do not change, while the transmission ratio changes.

During the operation in the high polarity mode, the two movable half pulleys move in the same direction, in such a way as to always maintain a perfect aligning of the two pulleys.

As the motor is switched off, the device recovers to the initial condition thereof, owing to the action of the spring on the basket pulley.

As a variation, it is provided for a possibility of applying expandible masses, in addition to the driving pulley, also to the basket pulley.

in this case, as said motor is supplied with high polarity, that is with a high revolution number, the axial shifting of the basket pulley does not cause the spring to overload and accordingly does not request a greater driving power from the motor: in the case of this latter variation the overload of the spring is cancelled by the centrifugal force exercised by said expandibles masses.

The instant device further provides for a possibility of using an electromechanic type of apparatus or a mechanic device effective to lock the masses located on the driving pulley as it is actuated.

Thus two speeds will be provided, simply by switching the motor poles and with a fixed transmission ratio-(engaged mass locking device)-with the addition of a third speed, as obtained by changing the transmission ratio by varying the pulley diameter-(disengaged mass locking device).

These and other characteristics, of operative and structural nature, of the device according to the present invention will become more apparent from the several figures of the accompanying drawing, where: figure 1 is a cross-section view of the device according to the present invention, provided with expandible masses located on the driving shaft, during the low revolution number mode of operation; figure 2 illustrates the device shown in figure 1 during the high revolution number mode of operation; figure 3 illustrates the expandible mass half pulley device, said expandible masses being provided with an expansion electromechanic locking device, during the low revolution number mode of operation:: figure 4 illustrates the device shown in figure 3 during the high revolution number mode of operation; figure 5 illustrates by a plan view the mass expansion electromechanic locking device, in the starting position thereof, as the motor operates at a low revolution number; figure 6 illustrates by a cross-section view that same device in the starting position or condition thereof; figure 7 illustrates the device in an intermediate position thereof, as the motor operates at a high revolution number; figure 8 illustrates said device in the centrifugal mass disengaging position thereof; figure 9 illustrates the position or condition assumed by said centrifugal masses after a full expansion.

Referring particularly to figures 1 to 4, the improved device according to the present invention provides for the use of two half pulleys, (1) et (2), of varying diameter, respectively a driving pulley and a driven pulley, that is applied to the basket shaft.

The driving pulley (1) is formed by two half pulleys (3) and (4).

More specifically said half pulley (3) is made rigid with the driving shaft (5), while the other pulley (4) is able of sliding along the axis of said driving shaft.

To the movable half pulley (4) expandible masses (6) are appliedi said expandible masses being housed between said movable half pulley (4) and a disk element (8), having a suitable shape.

The expansion of the masses (6) applied to the movable half pulley (4) causes said movable half pulley (4), as the polarity of the motor is changed, to axially move and accordingly the driving pulley (1) useful diameter is varied.

The driven pulley (2) of the basket (9) is also formed by two half pulleys (10) and (11), one thereof being fixed and the other being movable on the shaft (12) of said basket.

The device according to the invention further provides for the connection of a spring (1 3), acting as an expansion element and pressing the movable half pulley (10) in such a way as to prevent said movable pulley (10) from moving due to the belt pulling action and the motor (14) working couple.

According to a variation thereof, the instant device provides for the applying of expandible masses (15) amso to the half pulleys (10) et (1 1), as it is illustrated in figures 3 and 4, thereby the overload of the spring (13) is cancelled or compensated for by the centrifugal force exercised by the masses (15).

In said figures 3 and 4 is furthermore illustrated an electromagnetic device (16), provided with holding members (17) effective to lock the expandible masses (6).

Thus, two speeds will be provided, as obtained by simply switching the motor poles and with a fixed transmission ratio-(engaged mass locking device)-, with the addition of a third speed, as obtained by changing the transmission ratio, by varying the pulley diameter( disengaged mass locking device)-.

According to another variation, the device may be formed by a mechanic assembly, illustrated in figures 5 to 9, comprising centrifugal masses (21) which are prevented from expanding, as the motor operates at a low revolution number, by the action exerced by the springs (25).

Under these conditions, the ratchet gear (22), able both of rotating about an axis, and of oscillating perpendicularly to said axis, is maintained into position by the spring (23).

As the motor is in the high revolution number mode of operation thereof, said centrifugal masses move outwardly, thereby causing said ratchet gear (22) to rotate in the plane.

However, as the pin (24) located on said masses (21) engages the ratchet gear slot, said masses are prevented from fully expanding and accordingly said half pulley is prevented from axially moving.

Figure 9 illustrates the device in the disengaging condition thereof, in which it is ready for fully expanding said masses (21), as the supply to the motor is switched off for a desired period of time.

In this case the motor revolution number decreases and accordingly the centrifugal force of the masses (21) also decreases in such a way that the springs (25) overcome said masses force, recovering said masses towards the centre.

Thus the ratchet gear (22),-owing to the action of the spring (23), rotates in the plane, thereby reaching the position illustrated in the figure, and presenting a slanted plane, formed in the groove contour, to the pin (24) of the mass (21).

By switching on again the supply to the motor, said centrifugal masses are caused to fully expand: the pin (24) of the masses (21) acts on the slanted or inclined plane of the ratchet gear (22), thereby causing said ratchet gear to upwardly rotate and eliminating any obstacles to the travel thereof.

Accordingly said masses (21) move to the position illustrated in figure 9, causint the pulley to axially move, thereby providing the third rotation speed of the basket.

To the above it is to be added that the illustrated mechanic type of device, due to its enclosed shape, does not require further lubricating, servicing and adjusting operations.

Further it does not require for the control any' outside connections such as wires, levers and the like.

The device according to the invention, particularly effective to be applied to washing machines has been thereinabove described and illustrated only as an illustrative but non limitative example of the structural characteristics thereof.

Accordingly it should be apparent that modifications and variations may be brought about to the instant device, without departing from the scope of the invention.

Claims

1) An improved device for transmitting movement, effective to be applied to washing machines, characterized in that said device provides for the use of two varying diameter pulleys, respectively a driving one and a driven one, this latter being applied to the basket shaft, said driving pulley being formed by two half pulleys, one thereof being rigid with said driving shaft, while the other is able of sliding along the axis of said driving shaft; to said movable half pulley being furthermore applied expandible masses, said masses being housed between said movable pulley and a disk element.

2) An improved device according to the preceding claim, characterized in that said device is provided with expandible masses, said expandible masses being applied to said movable pulley and being effective, as said motor revolution number varies, to cause said movable half pulley to axially move and, therefore, said driving pulley useful diameter to vary.

3) An improved device according to the preceding claims, characterized in that said device is provided with a basket driven pulley, said basket driven pulley being formed by two half pulley, one thereof being fixed and the other being movable on the shaft of said basket, being furthermore provided a spring acting on said movable half pulley for preventing this latter from moving or shifting due to the belt pulling action and said motor working couple.

4) An improved device according to the preceding claims, characterized in that said device comprises expandibles masses, said expandible masses being applied on the basket half pulley shaft, in such a way that said spring overload is cancelled by the centrifugal force exercised by said expandible masses.

5) An improved device according to the preceding claims, characterized in that it comprises an electromagnetic device having holding members effective to lock said expandible masses, in such a way as to provide two speeds, as obtained only by switching said motor poles and with a fixed transmission ratio-(engaged mass locking device)-with the addition of a third speed, as obtained by changing said transmission ratio by varying said pulley diameter (disengaged mass locking device)-.

6) An improved device according to the preceding claims, characterized in that il comprises expandibles shaped and driven masses, said masses being coupled to said one half pulley and being connected to one another by springs and ratchet gears, thereby as the motor high speed is firstly inserted, said ratchet gear prevents said masses from expanding, the basket revolution number being directly depending on said motor polarity; a third basket speed being possible by causing said masses to completely expand and hence said half pulley to axially move; an instantaneous interruption of said motor supply causing said masses to move towards the centre and locate in a disengagement position with respect to said ratchet gear for a complete expanding of said masses.

7) An improved device according to the preceding claims, characterized in that it comprises spring pairs effective to prevent said expandible masses from centrifugally expanding as said motor operates at a low revolution number, said masses being furthermore provided with a pin effective to engage with a slot formed in a ratchet gear held in position by a spring.

8) An improved device according to the preceding claims, characterized in that in order to cause said masses to disengage, it is necessary to interrupt, for a desired period of time, the supply to said motor, thereby by decreasing said motor revolution number, said masses are moved towards the centre by their respective springs; and said ratchet gear, due to the action of the spring coupled thereto, rotates in the plane, thereby presenting to said mass pin an inclined or slanted plane formed in the outline of the groove.

9) An improved mechanic device according to the preceding claims, characterized in that by recovering said motor supply, said mass pin acts on said ratchet gear slanted plane, causing said ratchet gear to upwardly rotate in such a way as to permit said masses to radially move, thereby causing said pulley to axially move and providing the basket third rotation speed.

10) An improved mechanic device according to the preceding claims, characterized in that said ratchet gear, in operation, is able both of rotating about an axis and swinging perpendicularly to said axis.

11) An improved mechanic device according to the preceding claims, characterized in that the mass, ratchet gear and spring assembly forming said device is contained into said pulley size.

12) An improved device for transmitting movement, effective to be applied to washing machines substantially as described with reference to the accompanying drawings.