US 3643277 A
A device for cleaning venetian blind slats includes a housing having spaced opposite sidewalls defining an inlet opening for the slats respectively. A substantially horizontal slat passage plane is defined between the apertures within the housing and the clamping points of two pairs of superposed driving rolls having rubber-elastic surfaces and arranged adjacent the respective apertures and provide guiding means for the slats for delivering the slats between two horizontally spaced pairs of cleaning rolls. The apparatus also includes a horizontally arranged spray pipe connected to a pressure line for applying a cleaning fluid in the vicinity of the space defined between the two cleaning roll pairs. The spray pipe advantageously defines a slat guide channel having a convergent entrance for guiding the slats therethrough.
Description (OCR text may contain errors)
United States Patent Durst Feb. 22, 1972  DEVICE FOR CLEANING VENETIAN 2,318,884 /1943 OKelley ..15/77 BLIND SLATS 2,933,746 4/1960 Frand ..15/77 x I 3,060,477 10/1962 Wechsler.... /77 1 lflvemofl g oberwemngefl-schofillsdorfl 3,178,745 4/1965 Kleebauer ..15/77 W1 zer an Prima Examiner-Edward L. Roberts  Flled July 1969 Att0rn 2y-McGlew and Toren  App]. No.: 840,732
 ABSTRACT Foreign Application i ity Data A device for cleaning venetian blind slats includes a housing July 12 1968 Switzerland ..10649/68 having Spaced PPOSite sidewalls defining inlet Waning May 1969 Switzerland 7530/69 the slats respectively. A substantially horizontal slat passage plane is defined between the apertures within the housing and 52 us. C1 ..15/77 the clamping Points of Pairs Superpmd driving M15  A46) 13/04 having rubber-elastic surfaces and arranged adjacent the  Field of Search 15/4 77 88 102 respective apertures and provide guiding means for the slats for delivering the slats between two horizontally spaced pairs  References cued of cleaning rolls. The apparatus also includes a horizontally arranged spray pipe connected to a pressure line for applying a UNITED STATES PATENTS cleaning fluid in the vicinity of the space defined between the two cleaning roll pairs. The spray pipe advantageously defines sl l f et a slat guide channel having a convergent entrance for guiding i er the slats hereth ou h. 2,282,628 5/1942 Whann et al ...l5/77 X t r g 2,313,606 3/ 1943 Webb et a1 ..15/77 10 Claims, 2 Drawing Figures T T W 3 SHEET 1 HF INVEAZIOR. FEL M! UUPST DEVICE FOR CLEANING VENETIAN BLIND SLATS This invention relates in general to cleaning devices and in particular, to a new and useful device for cleaning blind slats which are adapted to be used for venetian blinds.
It is very difficult to clean the slats of so-called venetian blinds. Such slats gradually accumulate dust and dirt which can no longer be removed by simple wiping. Cleaning may only be effected by laborious and time-consuming cleaning process which may even lead to the damage of the blind. It is an object of the present invention to provide equipment for cleaning the slats which renders it possible to clean the slats in a continuous process rapidly and satisfactorily after they have been removed from their carrying elements. For this purpose, the equipment according to the invention is characterized by the use of a housing of generally block-shaped configuration with opposite end walls having respective inlet and outlet openings. A passage plane is defined between the inlet and outlet opening within the housing and two pairs of superposed drive rollers having rubber-elastic surfaces are respectively arranged adjacent to the inlet and outlet and provide means for guiding the slat through the cleaning plane. Between the two clamping rollers are arranged two pairs of superposed clean ing rollers which rotate about horizontal axes and have contact points which are arranged in the horizontal slat passage.
A feature of the invention is the provision of a spray pipe which defines a horizontal passageway having a converging entrance for centering the slat for passage through the horizontal plane with means for directing a cleaning liquid into the chamber of the pipe at which the liquid may contact the slat. A slat which is introduced lengthwise through the inlet opening into the passageway will be guided through .the tube during the operation of the equipment by the first clamping roll pair and will be transported between the rolls of the first cleaning roll pair, past the spray pipe and subsequently between the rolls of the second cleaning roll pair. The slat will then be ejected by the last clamping roll pair through the outlet opening. If cleaning fluid is applied to the spray pipe and to a guide channel which may be defined by the spray pipe and which opens at each end to permit passage of the slat therethrough the fluid will exert a washing jet effect on the slat.
An especially advantageous slat cleaning roll arrangement according to the invention is characterized by a cleaning roll pair formed of two brush rolls superposed with some circumferential clearance. One of the brush rolls is drivable in a direction to entrain the slats and the other is drivable in an opposite direction and the shaft of these brush rolls are offset relatively to each other in the passage direction of the slats so that the entraining brush roll follows the counterdriving roll in the passage direction. The second cleaning roll pair is formed by a drivable brush roll which entrains the slat and lies on the same side of the passage path as the entraining brush roll of first cleaning roll pair. The freely rotatable counterroll of the second roll pair is arranged with a circumferential clearance relatively to its associated brush roll and it is provided with a rubber-elastic layer. The shaft of the two cleaning rolls are offset relative to each other in the passage direction of the slats, so that the entraining brush roll precedes the counter roll in the passage direction. A guide element for each pair is provided between the two cleaning roll pairs so that the tranversing slat will be guided toward the circumference of the following entraining brush roll. With the inventive arrangement each slat which is put in lengthwise into the passage path will be satisfactorily cleaned and safely passed through the various roll pairs without being deviated or bent by any of the cleaning equipment. The guide elements may take the formof stationary guide brushes for example.
Accordingly, it is an object of the invention to provide an improved slat cleaning device which includes a housing defining a substantially continuous slat passage and with clamping rollers, arranged adjacent the inlet and outlet respectively, which have nips which are arranged along the slat passage and further with one or more set of cleaning rollers arranged between the driving rollers and in position to engage the slat moving along the passage, and preferably with means for introducing a cleaning fluid to the slats in the vicinity of the cleaning rollers.
A further object of the invention is to provide a device for cleaning the slats of venetian blinds and the like which is simple in design, rugged in construction, and economical to manufacture.
FIG. 11 is a vertical sectional view of a venetian blind slat cleaning device constructed in accordance with the invention; and
FIG. 2 is a view similar to FIG. I of another embodiment of the invention.
Referring to the FIG. I of the drawings in particular, the in vention embodied therein comprises a supporting frame 1 for a housing or block-shaped container .2 having a removable cover 2a. One end wall of the container 2 has a centrally posi tioned inlet opening 3 which is surrounded by an inlet chute or guide 4 and which is arranged directly opposite to an outlet opening 5 in an opposite end wall of the housing, which in turn, is surrounded by an outlet chute or guide 6.
In accordance with the invention a pair of superposed drive rolls or clamping rolls 7a, 7a, and 7b, 7b, are rotatably mounted in the sidewalls of the housing and define a nip or clamping point which lies in the horizontal passage plane for venetian blind slats which are to be cleaned by passage through the housing through the openings 3 and 5. At least one surface layer of the drive rolls 7a and 7b comprises a rubber or other rubber-elastic material permitting deformation of the roller to adapt itself to the usually slightly arched profile of the venetian blind slat without danger of damage to the latter. The roller set 7a, 7a is located adjacent the inlet 2, and the roller set 712, 7b is located adjacent the outlet 5. The lower rolls of each roller sets 7a, 7a and 7b, 712 each carry on one shaft end a gear or sprocket 8 over which a drive chain 9 is guided. The drive chain 8 is also guided over guide wheel 10 and a pinion sprocket 11a which is rotated by a small driving motor 11 which is mounted on the frame 1. The upper rolls of each of the driving rolls sets 7a and 7b are entrained by the lower rolls by friction.
In the spacing between the two roll sets 71: and 7b there are arranged two pairs of superposed brush rollers 12a and 12a, and 12b and 12b which have nips which are disposed in the passage plane for the venetian blind slat. An endless drive belt or chain 13, is driven from a sprocket 14a which is rotated by a small motor 14 on the frame 1 and it drivingly engages sprocket wheels 15 affixed to each axle of each of the brush rolls 12a, 12a and 12b and 12b. Guide rollers 15a, 15b also engage the chains 13 and provide the proper operating tension arrangement. The drive arrangement is such that the rolls 12a and 12a at the inlet side rotate in the same direction of rotation as each of the sets of the driving rolls 7a and 7h. The brush rolls 12b and 12b, however, which are closer to the outlet opening 5 rotate in an opposite direction of rotation as indicated by the arrows in the drawing.
The coverings of the brush rolls 12a and Ila on the inlet side are made relatively hard while the coverings of the rolls 12b and 12b adjacent to outlet side is somewhat softer. For this purpose the rolls 12a and 12a carry a more dense set of harder bristles while the rolls 12b and 12b carry a less dense set of softer bristles. By making the brush rollers 12b and 12b softer there is less likelihood of a breaking of the slats by the braking action of the rollers 12b and L2b. The interior of the housing includes U-shaped guides 2b at the interior of the cover 2a which engage over packing elements 25 of U-shaped cross section for partition wall members 16a, 16a. The partition wall members 16a, 16a carry central portions with bendable brush strips 52 which are arranged to make contact with the venetian blind in the passage plane. The lower brush strip 52' is supported by an upward extension 16b of the partition wall which is arranged on feet or brackets 17 within the housing 2.
In accordance with a further feature of the invention there is provided a horizontally extended guide channel 18 having a passage defined therethrough arranged in the passage plane for the venetian blind slat. The guide channel 18 includes a convergent entrance end for facilitating the guiding of the slat into the passage thereof. The guide channel 18 is formed as a continuation of a vertical pressure pipe 19 which discharges through openings or bores 20 into the horizontally arranged passage 18 for the slat.
An electric motor 21 drives a feed pump 22 which is connected to a fluid tank 23 at its suction side and discharges upwardly through the pressure pipe 19. The tank 23 is provided with a normally closed bottom drain 23a and an upper scum overflow 23b. Two immersion pipes 24 are connected to bottom apertures of the housing 2 and provide a drain for the housing interior. In order to facilitate the entrance and removal of the slats to be cleaned, the entrance guide 4, and the discharge guide 6 are provided with tubular conduit formations 26a and 26b which are extractable to adapt to the length of the slats to be cleaned.
The operation of the device is as follows: A slat L to be cleaned is guided on the inlet side through the conduit 26a and the inlet opening 3 to the clamping point of the drive roll 7a, 7a. The slat is then conveyed by the transporting effect of the engagement between the nip of the rolls 7a, 7a and enters between the brush elements 52, 52' and rotating brushes 12a, and 12a. The slats are then directed through the funnel shaped entrance of the guide channel 18 and pass through the channel, and as they do so cleaning fluid is directed through pipe 19 and over the surface thereof. The slat then moves between the brushes 12b and 12b as they are clamped by the dry rolls 7a, 7a, so that there is a counter movement cleaning of the slats by the counter rotating brushes 12b and 12b. The slats are long enough to permit engagement of the forward end thereof by the roller set 7b, 7b to effect removal of the slat through the outlet aperture and the conduit 26b.
The cleaning fluid which collects in the housing 2 is returned to the tank 23 through the pipes 24. Foaming in the tank is prevented or at least greatly reduced by the use of the emergent pipe 24 which extend far below the liquid level in the tank 23. The drives of the driving rollers sets 7a, 7a and 7b, 7b and the brush roller sets 12a and 12a and 12b and 12b are also advantageously made adjustable in respect to speed to thus vary the mechanical cleaning action. Thus, the equipment can be adapted in a simple manner both to profile size, length and cleaning effect.
In the embodiment indicated in FIG. 2, there is provided a frame which supports a housing 32 of generally rectangular cross section having a removable cover 32a. One end of the housing includes an opening 33 for an inlet and the other end includes an opening 35 for the outlet and a cleaning passage plane between the inlet and outlet is defined within the interi or of the housing. This embodiment includes a driving roller set 37a and 37a adjacent to inlet 33, and a driving roller set 37!) and 37!) adjacent to outlet 35. The engagement points or the nip between the roller sets lie generally along a horizontal plane in alignment with the inlet 33 and the outlet 35. An electric motor 41 mounted on the frame 31 is arranged to drive the individual roll sets in a manner similar to the embodiment of FIG. 1. In addition, the roll sets comprise a rubber-elastic material which can adapt to the usual odd shape profile of the slats to be cleaned. A cleaning zone 36 is defined within the interior of the housing 32 between upper partition walls 45a and 45a and in this zone there is arranged two pairs of superposed cleaning rolls 40a and 40b and 42a and 42b which are arranged at spaced locations along the passage defined for the slat movement. The first cleaning roll pair 40a and 40b is formed by two brush rolls offset relatively to each other in a direction of slat passage and the amount of axial offset a is selected so that the upper roll 40a follows the lower roll 40 b in the passage direction. The second cleaning roll pair in the direction toward the outlet opening 35 includes an upper roll 420 which is offset from the lower roll 42b in a direction opposite to the passage direction of the slat. The amount of axial offset b of the two rolls 42a and 42b is selected so that the upper brush roll precedes the lower counter roll 42b in respect to contact with the slat. The counter roll 42b is mounted to be freely rotatable but the brush rolls 42a and 40a and 40b are drivable via an endless drive member 43 which is moved by an electric driving motor 44. For this purpose the motor drives a sprocket 60 and individual sprocket wheel 62 affixed to each of the rollers 40a, 40b, and 42a. The direction of rotation of the rolls 42a, 40a, and 40b is selected so that, with respect to the passing slat, the upper brush rolls 40a and 420 are entraining the lower brush roll 40b which is driving in a counter direction.
The cleaning zone 36 is separated by wall portion 45a, 45b, 45a and 4511. The lower separating wall portions 45b and 45d are provided with guide brushes or vertically arranged contact brushes 46a and 46b respectively, and a guide brush or contact brush 460 is arranged to project upwardly through the movement passage for the slat between the roller sets within the cleaning chamber 36 and an additional upper brush or contact brush 46f is arranged to act downwardly upon the slat adjacent to lower brush or contact brush 46b. A contact brush 4611 projects downwardly at the entrance aperture and a similar contact brush 46c projects upwardly at the discharge aperture 35. A spray pipe 49 is arranged below the cleaning passage for the slat and it includes a top nozzle 64 which is directed upwardly against the slat as it moves through the cleaning passage 36. A pump 52P which is driven by an electric motor 66 takes suction from a tank 53 and discharges it through the conduit 49 and the nozzle 64, The liquid may pass through a sieve 50 into the end zone of the housing 32 and flow downwardly through a drain 54 back into the tank 53. Any fluid which is hurled by the brush roller sets 40a and 40b and 42a and 42b, toward the inlet side will also move into the end zone while the end zone at the outlet side of the housing will be shielded from spray water of the brush rolls by the partition wall 45c and the brushes 46b and 46f. With such an arrangement the driving rollers at 37b and 37b remain dry. Water of condensation which precipitates on the inner wall of housing 32 adjacent to outlet opening 35 is collected by a trough 51 and can flow off on the sides of the housing. Any liquid reaching the end zone of the housing 32 on the inlet side will return to the tank 53 through the pipe 54.
The operation of the device indicated in FIG. 2 is as follows: The slat to be cleaned is pushed lengthwise through the inlet aperture 33 between the driving rollers 37a which provide for the onward transport of the slats. The slats are usually oriented with the most soiled side upwardly and in the case of the arched slat this is usually the outside of the arch. The brush 46a lightly presses against the slut in an upward direction and thus positions it to be entrained between the roller sets 40a and 40b. Owing to the axial offset a of the two rollers 40a and 4017 the counter driving brush rollers 40b becomes operative only when a relatively long slat pieces en train by the upper brush roller 40a in the passage direction. As the slat leaves the two brush rollers 40a and 40b it is lightly directed downwardly by the action of these two rollers until it strikes against the brush 46c, which, in turn, presses the slat back upwardly so that the latter comes into contact first with the entraining brush roll 42. The axial offset b of the brush roll set 42a and 42b insures that the idle roll 42b will not brake the slat undesirably. The slat leaves the roller set 420 and 42b with a slight upward orientation until it contacts the brush 46f which directs it back between the driving roll set 37b and 37b. These latter driving roll sets serve as squeezing rollers and remove some of the moisture as the slat is directed outwardly through outlet opening 35 over brush 46c. The brushes 46c and 46b increase the dimensional stability of the operation of the device.
It has been found that not only a desirable cleaning of the slats is insured with such arrangement but any laterally roll deviation or vertical bending of the slats is avoided.
In the foregoing it has been assumed that the slats are introduced into the equipment with the outside of their arch facing upwardly. if it is desired to send the slats through the equipment in the reverse manner, the brush rolls 40a and 42a should be at the bottom and the rolls 40b and 42b arranged at the top, and the axial offset and driving direction is maintained in a similar manner. It would also be possible in both cases to arrange the two cleaning roll pairs mutually interchanged.
The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:
1. A device for cleaning blind slats comprising a housing having an inlet opening adjacent one end and an outlet opening adjacent the opposite end, first and second sets of superposed clamping rollers rotatably mounted within said housing adjacent to the inlet opening and the outlet opening, respectively, and each defining a nip therebetween for the passage of a slat therethrough, first and second sets of spaced apart superposed cleaning rollers rotatably mounted within said hous ing between said first set of clamping rollers and said second set of clamping rollers and defining a nip therebetween located to facilitate passage of a blind slat from the first set of clamping rollers to the first set of cleaning rollers and to the second set of cleaning rollers and then to the second set of clamping rollers, at least one upwardly directed guide brush engageable with a slat for guiding said slat into the nip between the said first and second cleaning roller sets, and spray cleaning means located between and below said first and second set of cleaning rollers for directing a cleaning fluid upwardly against the slat being moved between said cleaning rollers and upwardly in the housing surrounding said cleaning rollers and permitting the spray to rain downwardly over the slats entering and leaving each cleaning roller.
2. A device, according to claim 1, said guide brush including a vertically arranged contact brush located between said first clamping rollers and said first cleaning rollers.
3. A device, according to claim 1, said spray means including a vertical fluid pressure pipe extending upwardly in said housing between said first and second cleaning roller sets, said spray means comprising means for directing the liquid upwardly through said pressure pipe.
4. A device, according to claim 3, including a fluid tank connected to said housing and providing a drain for said housing, and a pump connected to said pressure pipe and said tank for taking suction from said tank to deliver cleaning fluid to said pressure pipe, said tank having pipe means extending downwardly into said tank below the liquid level thereof from said housing.
5. A device, according to claim 1, wherein said first cleaning roll set comprises two superposed brush rolls having circumferential clearance therebetween, one of said brush rolls being driven in one direction and the other said brush rolls being driven in an opposite direction, said brush rolls being offset in respect to the passage direction of the slat therebetween so that one of said rolls comprises an entraining brush following the other of said rolls.
6. A device, in accordance to claim 5, wherein one of said brush rolls is arranged on the top of the slat passage path, said housing being divided by partitions into end zones each accommodating a respective one of said first and second clamping rollers and a central cleaning zone carrying said first and second cleaning rollers, said partitions including said guide brush contacting the slat for deflecting it in respect to said cleaning rollers to insure that it enters therebetween.
7. A device, in accordance to claim 1, wherein said first and second sets of cleaning rollers include upper rollers which are offset in directions toward each other and lower rollers which offset in directions away from each other.
8. A device, according to claim ll, wherein said first set of cleaning rollers comprises an upper roller offset in a direction forwardly in respect to slat passage direction and said lower roller, said second set of cleaning rollers including an upper roller which is offset in a direction opposite to the direction of movementpf slat therebetween.
9. A device, according to claim 8, said guide brush being arranged between said first and second cleaning roller sets and acting upwardly against a slat movable therebetween, and a second brush located between said second clamping roll set and said second cleaning roller set and acting downwardly in respect to the passage of the blind slat.
10. A device, according to claim 1,. wherein said housing carries a liquid collecting trough adjacent the outlet aperture.