Improvements in detergent distributors for laundry washing machines

Abstract

 A detergent distributor for a laundry washing machine comprises a plurality of compartments for containing detergents and additives, and a piston guided therein for rectilinear displacement into a plurality of operating positions for directing water provenient from a water supply circuit into selected ones of said compartments in each of said positions, said piston being adapted to be actuated by at least one cam of the program unit of the machine through at least one lever.
In order to enable the play within the actuating mechanism of said piston to be properly adjusted so as to align the piston accurately in its individual operating positions, the invention provides that the lever is pivotally mounted on the frame of the machine in proximity to said cam, and is formed with at least two diverging arms in the shape of a fork, one of said arms being connected to said piston, said lever being further provided with cam follower means resiliently biased into engagement with said cam, and with means for adjusting the distance between the two arms of said fork configuration.

Description

[0001] This invention relates to a detergent distributor for a laundry washing machine provided with a device for controlling the introduction of water selectively in to each compartment of the distributor itself.

[0002] Already known are various devices for selectively controlling the introduction of water into the individual compartments of the detergent distributor of a laundry washing machine.

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

[0004] This piston is provided with at least one internal through- bore the inlet opening of which is always in communication with the water supply conduit of the machine through a per se known air break located therebetween, while its outlet opening is adapted to selectively communicate with different conduits formed in a manifold extending above the various compartments of the detergent distributor, each of said conduits being associated with one of said compartments.

[0005] In this manner, water is introduced into a single compartment of the distributor for each position of the piston.

[0006] For ensuring the correct operation of this detergent distributor, the lever system is dimensioned in such a manner that the piston can always be displaced into its predetermined operative positions.

[0007] In addition, the distributor is also provided with means for controlling the play existing between the lever system and the piston, said means acting on said lever system in such a manner as to limit the movements of the levers themselves to a sufficient degree for ensuring a correct displacement of the piston.

[0008] To this effect, said control means comprises a small plate connected laterally to the detergent distributor, a lever of said lever system being pivotably mounted on said plate, said lever acting directly on said piston.

[0009] There is further provided an adjustment knob cooperating with said plate so that actuation of said adjustment knob results in a limited displacement of said plate and thus of the fulcrum point of said lever so as to achieve a satisfactory and reliable adjustment of the piston play.

[0010] In the case under consideration, however, the adjustment of the play effected in this manner is rendered difficult by the fact that the adjustment means is located at the rear portion of the control panel of the machine and is thus accessible only after dismantling the control panel itself.

[0011] It is an object of the present invention to eliminate the above noted disadvantage by providing a detergent distributor for a laundry washing machine including means for adjusting the piston play directly accessible from the exterior of the machine so as to permit the piston play to be adjusted in a simple and efficient manner.

[0012] This and other objects are attained according to the invention by a detergent distributor for a laundry wa shing machine comprising a plurality of compartments for containing detergents and additives therein, and a piston guided therein for rectilinear movement and designed to permit in each of its operative positions the introduction of water from the water supply circuit into a selective one of said compartments, said piston being adapted to be actuated by at least one cam of the program unit of the machine through at least one lever.

[0013] In accordance with the invention, a distributor of the above described type is characterized in that said lever is pivotally mounted on the frame of the machine in proximity to said cam and is formed with at least two diverging arms in the form of a fork, one of said arms being connected to said piston, said lever being further provided with cam follower means resiliently biased into contact with said cam, and with means for adjusting the distance between the arms of said fork configuration.

[0014] Further characteristics and advantages of the invention will become evident from the following description of an exemplary embodiment 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 structural details of the distributor shown in fig. 1 in a first embodiment of the invention, and

fig. 3 shows a top plan view of structural details of the distributor shown in fig. 1 in a modified embodiment of the invention.

[0015] Shown in fig. 1 is the top portion of a laundry washing machine 4 of the top loading type, comprising a detergent distributor 5 having a plurality of compartments 6, 7, 8 and 9 which are accessible through respective upper openings and adapted to contain the detergents and additives required for the various operating cycles of the washing machine. Further provided is a control knob 12 acting on the programm unit (not shown) of the machine for selecting any specific operating cacle.

[0016] The top portion of the machine is provided with a protective cover 13 adapted to be raised to the position shown in the drawing for giving access to said openings, and with a removable protection plate 14 having a through- opening for receiving said control knob 12 therein,further opening being optionally provided for receiving additional control knobs or the like of the machine. The described detergent distributor 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.

[0017] Piston 16 is adapted to assume various operating positions in each of which it establishes communication between water supply conduit 15 and a selected one of said distributor compartments so as to selectively direct the water from said supply conduit to the respective compartment.

[0018] For purposes of the present invention, a detailed description of piston 16 may be omitted, as there are already known various embodiments thereof for the above stated purpose (see for instance applicant's Italian patent No. 1,045,343).

[0019] Referring now to fig. 2, the detergent distributor according to the invention is provided with a lever 17 mounted on the frame of the machine for pivotal movement about its mid portion in proximity to a suitably shaped cam 18 affixed to a shaft 19 of the program unit (not shown) of the machine.

[0020] Lever 17 comprises a rectilinear arm 20 provided with a laterally projecting cam follower element 21 and with a pair of arms 22 and 23 forming extensions of arm 20 and diverging in the form of a fork. Arms 22 and 23 are of different lengths, the longer arm 22 having iiP end portion formed with a slot 24 for receiving therein a pin 25 formed integrally with piston 16.

[0021] In particular, lever 17 cooperates with per se known resilient means (not shown) adapted to continually bias cam follower element 21 into contact with the outer periphery of cam 18, so that rotation of cam 18 in the direction of arrow A under the control of the program unit results in simultaneous displacement of arms 22 and 23 of lever 17 and thus, due to the engangement of arm 22 with piston 16, in a corresponding displacement of the latter towards ore of its operating positions.

[0022] The described system for actuating piston 16 inevitably envolves the presence of a certain play between lever 17 and piston 16, whereby the stroke of piston 16 may become inaccurate, so that the piston does not assume its correct operating positions. For eliminating this play and thus for ensuring accurate actuation of the piston, the invention provides adjusting means comprising two toothed sections 26 and 27 formed opposite one another on the lateral surfaces of the two lever arms 22 and 23 of lever 17, and a toothed roller 28 disposed between toothed sections 26 and 27 and in engagement therewith. Roller 28 has its top surface formed with at least one slot 29 accessible through a suitable opening formed in the frame of the machine for the introduction of a tool for rotating roller 28.

[0023] The play of piston 16 may thus be adjusted by rotating roller 28 in the manner described, so that its engagement with toothed sections 26 and 27 causes roller 28 to travel therealong, resulting in lever arms 22 and 23 being spread further apart or approaching one another.

[0024] Due to the engangement of lever arm 22 with piston 16, the rotation of roller 28 results in a corresponding displacement of piston 16, the amount of such displacement being ascertained by means of fixed reference marks visible through a window 30 formed in the frame of the machine (fig. 1).

[0025] Fig. 3 shows a modified embodiment of the described means for adjusting the piston play.

[0026] In this modification, lever 17 comprises an extended arm 31 mounted on the frame of the machine for pivotal movement about one of its ends and formed with a rectilinear portion 32 formed with a laterally projecting cam follower element 21 resiliently biased into engangement with the outer periphery of cam 18 fixedly mounted on the shaft 19 of the program unit (not shown) of trhe machine as in the embodiment described above.

[0027] Lever 17 is formed with a further arm 33 having a rectilinear portion 34 connected to rectiliniear portion 32 so as to form a fork configuration therewith, said arm having its free end portion engaged with piston 16 in the manner described above.

[0028] Arm portion 34 is formed with a threaded bore for receiving therein a screw 35 the free end of which abuts arm portion 32. The other end of screw 35 is formed with a suitably shaped head 36 accessible from the exterior of the machine and adapted to be engaged by a suitable tool by means of which screw 35 may be rotated so as to vary the distance between arm portions 32 and 34 for adjusting the play of piston 16 as described.

[0029] The means for varying the distance between the arm portions of the forked lever may of course take other forms than described with reference to the embodiments of figs. 2 and 3, as long as such means permit a simple and effective adjustment of the piston play by direct intervention from the exterior of the machine without the necessity to remove cover panels or other components of the machine as required in prior art.

[0030] In the described embodiments,the cover plate 14 serves exclusively decorative or aesthetic purposes and is adapted to be removably attached to the top portion of the machine without the employ of any tools.

[0031] In addition, the described means for adjusting the piston play is of compact design and can be actuated in a simple manner. The described device may be mounted in any convenient position also in a laundry washing machine of the front loading type without thereby leaving the scope and the spirit of the present invention.

Claims

1. A detergent distributor for a laundry washing machine, comprising a plurality of compartments for containing detergents and additives, and a piston guided therein for rectilinear displacement into a plurality of operative positions for directing water provenient from the water supply circuit to a selected one of said compartments in each said position, said piston being adapted to be actuated by at least one cam of the program unit of the machine through at least one lever, characterized in that said lever (17) is pivotally mounted on the frame of said machine (4) in proximity to said cam (18) and is provided with at least two diverging arms (22,23; 32, 34) in the shape of a fork, one of said arms being connected to said piston (16), said lever being further provided with cam follower means (21) resiliently biased into engagement with said cam, and with means (26 to 29; 35, 36) for adjusting the distance between the two arms of the fork configuration.

2. A detergent distributor according to claim 1, characterized in that the fulcrum point of said lever (17) is located at an intermediate position between said fork configuration (22, 23) and a further arm (20) of said lever , the free end portion of said further arm being laterally connected to said cam follower means (21).

3. A detergent distributor according to claim 1, characterized in that the fulcrum point of said lever (17) is located at the free end portion of a further lever arm (31) a portion of which forms one arm (32) of said fork configuration (32, 33) and is laterally connected to said cam follower means (21).

4. A detergent distributor according to any of the preceding claims, characterized in that said means for adjusting comprise two short toothed sections (26, 27) formed along mutually facing surfaces of the two arms (22, 23) forming said fork configuration, and at least one toothed roller (28) disposed between said toothed sections and in engagement therewith, said roller being adapted to be rotated over a limited range by means of a suitable tool adapted to be introduced into a corresponding recess (29) formed in the upper portion of said roller.

5. A detergent distributor according to any of the preceding claims, characterized in that said means for adjusting comprise at least one screw (35) engaged in a corresponding threaded bore in one arm (34) of said fork configuration (32, 34) and having its free end in abutment with the other arm (32) of said fork configuration, said screw having a head portion (36) adapted to be engaged by a suitable tool for rotating said screw over a limited range.

Drawing