Detergent distributor for laundry washing machine

Abstract

 A detergent distributor for a laundry washing machine comprises a reciprocating piston for controlling the supply of water to individual compartments containg detergents and/or additives. The piston is actuated by a cam of a program unit of the machine through a lever system. According to the invention, the operative connection between said cam and said piston is accomplished by a pair of pivotally mounted and interconnected levers one of which carries a cam follower element biased into engagement with said cam, while the other is connected to said piston an provided with play adjustment means in the form of an excentrically mounted shaft which by means of a suitable tool is rotatable from the outside of the machine for displacing the fulcrum point of said other lever.

Description

[0001] The present invention relates to a detergent distributor for a laundry washing machine provided with an arrangement for the selective supply of water to each compartment of the detergent distributor.

[0002] Already known are various types of devices for the selective supply of water to the individual compartments of the detergent distributor of a laundry washing machine.

[0003] Specifically, there is known a device of this type comprising a piston guided for rectilinear reciprocating movement and actuated by at least one cam of a program unit of the machine through an articulated lever system.

[0004] The above noted piston is provided with at least one internal through- bore the inlet opening of which is always open towards the water supply conduit of the machine from which it is separated by a per se known air break or the like, while the outlet opening of said bore is selectively communicable with various passages formed in a manifold element disposed above the various compartments of the detergent distributor, each of said passages being associated with one distributor compartment. At each position of the piston, water is thus supplied to a specific single distributor compartment.

[0005] For ensuring correct operation of a detergent distributor of this type, the lever system is dimensioned such that the piston is always moved to accurately determined operative positions. f

[0006] The detergent distributor is additionally provided with means for adjusting the play existing between the lever system and the piston, said means acting on the lever system in such a manner as to limit the free movement of the levers sufficiently for ensuring an accurately determined stroke of the piston. To this effect, said adjustment means comprises a support plate connected to one side of the detergent distributor and supporting the fulcrum of one of the levers of the lever system, said one lever acting directly on the above noted piston.

[0007] There is further provided an adjustment knob cooperating with the support plate, the actuation of which results in limited displacement of said support plate and thus of the fulcrum of said lever, thus providing for a satisfactory and reliable adjustment of the piston play.

[0008] In the case under consideration, however, the adjustment of the piston play accomplished in the described manner offers certain difficulties, as the described adjustment means is mounted_rearwards of the control panel of the machine, so that it is accessible only after this panel has been dismounted.

[0009] It is an object of the present invention to eliminate the above-noted inconveniences by providing a detergent distributor for a laundry washing machine, including an arrangement for adjusting the play of a distributor piston which is directly accessible from the outside of the machine after removal of a particular protective cover held in a snap engagement, so as to permit the piston play to be adjusted in a simple and efficient manner.

[0010] These and other objects are attained according to the invention by a detergent distributor for a laundry washing machine, comprising a plurality of compartments for detergents and/or additives, and a piston guided therein for rectinlinear reciprocating movement for selectively supplying water provenient from the water supply mains to individual ones of said compartments in each of its operative positions, said piston being adapted to be actuated by means of at least one cam of the program unit of the machine through a plurality of levers.

[0011] According to the invention, a detergent distributor of the above noted type is characterized by a first and a second lever connected to one another and fulcrummed with one end each on the frame of the machine in proximity of said cam, said first lever being provided with cam follower means resiliently biased into engagement with said cam, and said second lever being connected to said piston and provided with means for adjusting its fulcrum point.

[0012] The characteristics and advantages of the invention will become more evident from the following description of an exemplary embodiment thereof with reference to the accompanying drawings, wherein:

fig. 1 shows a partially sectioned perspective view of the top portion of a laundry washing machine provided with a detergent distributor according to the invention,

fig. 2 shows a top plan view of a structural detail of the distributor shown in fig. 1, and

fig. 3 shows a partial sectioned view of the detail shown in fig. 2, taken substantially along the line A-A.

[0013] With reference to fig. 1, there is shown the top portion of a laundry washing machine 4 of the top-loading type, comprising a detergent distributer 5 having a plurality of compartments 6, 7, 8 and 9 accessible through respective top openings and adapted to contain the various detergents and/or additives required for carrying out the various washing cycles of the machine. Further shown is a manual adjustment knob 12 acting on the program unit of the machine for selecting any specific washing program. The top portion of the machine is further provided with a protective cover 13 adapted to be raised to the position shown in fig. 1 for giving access to the compartments of distributor 5. Also provided is a removable protective cover 14 having at least one through-opening for accommodating said adjustment knob 12 and/or any other controls that may be required.

[0014] The detergent distributor under discussion is further provided with a water supply conduit 15 connected in a per se known manner to the water supply mains, and containing a piston 16 guided therein for rectilinear reciprocating movement.

[0015] Piston 16 is adapted to assume various operative positions in each of which it communicates the water supply conduit with a selected one of the distributor compartments so as to selectively supply water to any one of the compartments.

[0016] In context with the present invention, a description of the design of piston is not required, as there exist already various known embodiments of such piston for the stated purpose (cf. for instance Italian Patent No. 1,045,343 owned by Applicant).

[0017] Referring now to figs. 2 and 3, the free end of piston 16 is formed to the shape of a fork having a rectilinear slot 17 for the engagement of a pin 18 formed integrally with a lever 19.

[0018] Lever 19 comprises two rectilinear portions 20 and 21 connected to one another by an arcuate portion 22, and is pivotally mounted on the frame 23 of the machine with its rectilinear portion 21.

[0019] The fulcrum of lever 19 is formed by a rotatable shaft 24 excentrically connected to lever 19 and mounted on the frame of the machine. At its top, shaft 24 is provided with at least one recess 25 accessible through a corresponding opening formed in the frame of the machine for rotating the shaft within a limited range by means of a suitable tool.

[0020] Formed in rectilinear portion 21 of lever 19 is a slot 26 for the engagement of a pin 27 projecting from the free end of a further lever 28 disposed in a position below first lever 19.

[0021] Second lever 28 is pivotally mounted on frame 23 in proximity of the articulated connection between first lever 19 and piston 16, and is formed with a laterally projecting cam follower 29 cooperating with the preipheral profile of a control cam 30 fixedly mounted on a shaft 31 of the program unit 32 of the machine. The described lever system is additionally provided with per se known resilient means (not shown) adapted to bias cam follower 29 into engagement with cam 30.

[0022] Due to the slot and pin connection between levers 19 and 28, rotation of cam 30 in the direction of arrow B under the control of program unit 32 results in simultaneous pivotal movements of the two levers about their respective fulcrum points, and consequently in a displacement of piston 16 to its various operative positions specified above.

[0023] This system for actuating the piston inavoidably involves some play between the various elements, whereby the stroke of the piston tends to become inaccurate, resulting in deviations from its correct operative positions.

[0024] For adjusting this play and thus for ensuring correct positioning of piston 16, the invention provides adjustment means constituted by the above described rotatable shaft 24.

[0025] Adjustment of the piston play is effected by rotating shaft 24 over a limited range by means of a suitable tool inserted into recess 25 thereof, whereby the fulcrum point of lever 19 is displaced due to the excentric connection between lever 19 and shaft 24.

[0026] This results in a corresponding displacement of the other end of lever 19 engaged with piston 16 as described above, the resulting displacement of the piston being verified with the aid of suitable fixed reference marks visible through a window 33 (fig. 1).

[0027] It is thus possible to accomplish the adjustment of the piston play in a simple and efficient manner directly from the outside of the machine without the necessity of dismounting any panels or functional parts of the machine. In the embodiment shown, cover 14 has exclusively aesthetic and protective functions and may be attached and detached by employing a snap mounting without the aid of any tools. In addition, the described play adjustment means is of compact and simple construction and simple operation. It may be installed at any suitable position even in laundry washing machines of the front loading type without thereby exceeding the scope of the present invention.

Claims

1. A detergent distributor for a laundry washing machine, comprising a plurality of compartments for detergents and additives, and a piston guided therein for rectilinear reciprocating movement for selectively supplying water provenient from the water supply mains to individual ones of said compartments in each of its operative positions, said piston being adapted to be actuated by means of at least one cam of the program unit of the machine through a plurality of levers, characterized by a first and a second lever (19, 28) connected to one another and fulcrummed with one end each on the frame (23) of the machine (4) in proximity of said cam (30), said first lever being provided with cam follower means (29) resiliently biased into engagement with said cam, and said second lever being connected to said piston (16) and provided with means (24) for adjusting its fulcrum point.

2. A detergent distributor according to claim 1, characterized in that said first and second levers (19, 28) are disposed one above the other and are operatively connected to one another by a slot (26) and pin (27) arrangement.

3. A detergent distributor according to claim 1 or 2, characterized in that said adjustment means comprise a rotatable shaft (24) forming the fulcrum of said second lever (19), said rotatable shaft being excentrically connected to said lever and mounted on the frame (23) of the machine (4), and adapted to be rotated over a limited range by means of a suitable tool introduced into a corresponding recess (25) formed in the upper portion of the shaft.

Drawing