Classifications

• • D—TEXTILES; PAPER
  • D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
  • D06F—LAUNDERING, DRYING, IRONING, PRESSING OR FOLDING TEXTILE ARTICLES
  • D06F58/00—Domestic laundry dryers
  • D06F58/20—General details of domestic laundry dryers 
  • D06F58/206—Heat pump arrangements
• • D—TEXTILES; PAPER
  • D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
  • D06F—LAUNDERING, DRYING, IRONING, PRESSING OR FOLDING TEXTILE ARTICLES
  • D06F58/00—Domestic laundry dryers
  • D06F58/20—General details of domestic laundry dryers 
  • D06F58/22—Lint collecting arrangements

Definitions

• the present invention relates to an automatic cleaning arrangement for air filters, in particular an automatic cleaning arrangement for air filters adapted for use as applied to the drying circuit of a clothes drying machine.
• Appliances performing a drying duty may either be based on a heat-pump technology for their operation or make more traditionally use the condenser-type or exhaust-type working principles.
• the energy usage of a heat- pump tumble dryer is largely known to be smaller than the energy usage that is generally experienced in the use of a tumble dryer in which the process air, i.e. the air used for drying, is heated by means of electric heating elements.
• the process air i.e. the air used for drying
• a battery of filters in a series arrangement is interconnected with the drying circuit of the machine in view of performing as a barrier provided to retain the lint generating from the clothes being tumbled and prevent it from continuing along the circuit to eventually get trapped between the fins of the heat exchangers, thereby clogging them.
• a heat-pump tumble dryer which is provided with a kind of self-cleaning air filter.
• the drying circuit of this machine comprises a heat exchanger and a lint-retaining air filter, which are removably housed in an enclosure mounted on the rear side of the outer casing of the tumble dryer.
• a pan for collecting condensation water and a pan for collecting the water used to flush and clean the air filter are removably housed in an enclosure mounted on the rear side of the outer casing of the tumble dryer.
• a pan for collecting condensation water and a pan for collecting the water used to flush and clean the air filter respectively.
• respective drain conduits allowing the water collecting thereinto to flow off.
• the pans themselves are provided and arranged to feature an adequate filling level so as to ensure that the filter flushing water would not overflow or gush back.
• the programme implemented in a hardware module in the tumble dryer calls for part of the rinsing water, or even the condensation water itself, to be conveyed towards a nozzle by means of a pump.
• a water flow diverter is provided in the water carrying circuit in proximity of the pump to cater for the case that it is more advantageous or appropriate for the rinsing or washing water to be recycled rather than being sent to the nozzle.
• the air filter is hit by a jet of water that automatically flushes off the lint therefrom and causes it to collect and settle into the pan provided to collect the air-filter flushing water, as already mentioned hereinbefore.
• the nozzle is supplied directly from the main water supply line.
• the above-cited solution has a major drawback in that it makes use of a static air-filter cleaning arrangement.
• the air filter and the nozzle are in fact mounted in a stationary manner without any degree of freedom, so that they do not move relative to the structure of the tumble dryer as throughout the automatic cleaning operation of the filter, i.e. as the air filter is automatically cleaned.
• a further drawback derives from the fact that the nozzle only injects the water jet - always in the same direction and with the same intensity - onto just a part of the surface of the air filter.
• a further purpose of the present invention is to provide an automatic cleaning arrangement for air filters of the above-cited kind, which is further effective in attaining the above-noted object and purposes at fully competitive costs, .and is capable of being manufactured with the use of readily available equipment, tools and techniques.
• a further advantage relates to the possibility for the number of air filters to be arranged in series with each other for connection to the drying circuit to be reduced. According to the present invention, the above-indicated aims, features and advantages, along with further ones that will become apparent from the following disclosure, are reached in an automatic cleaning arrangement for air filters incorporating the characteristics as defined and recited in the appended claims.
• FIG. 1 is a schematic view of the automatic cleaning arrangement for air filters according to the present invention.
• FIG. 2 is a schematic side view illustrating the kinematics used to actuate the filtering unit and control the relative movement thereof.
• the automatic cleaning arrangement for air filters comprises a reservoir 10 for collecting and storing a liquid mass, a plurality of water-flow adjusting means 22 and 24, a pump
• a plurality of open-jet nozzles 40 and 42 an air filtering unit 50, an actuator means 60, and a control unit 70.
• the reservoir 10 may for instance be in the shape of a parallelepiped and is connected on top to a water-supply conduit 25 and a vent conduit 26.
• the water- flow adjusting means 22, which may for instance be an electromagnetic valve, is associated to the conduit 25 and performs to adjust the liquid mass being let into the reservoir 10. From the lower portion of the surface of the reservoir 10 there extends a conduit 29, to which there is preferably associated a water-flow adjusting means 24, which may for instance be an electromagnetic valve, which is used to control the flow of the liquid mass being let out by means of the pump 30.
• the pump 30 may for instance consist of a high-head, bi-directional delivery pump operated by a d.c. motor. From such pump there branch off a plurality of pipes 32 and 34 connecting the pump 30 to a respective plurality of bladelike-jet nozzles 40 and 42.
• Such bladelike-jet nozzles 40 and 42 are peculiar in that they provide a particular jet having a wide flare, i.e. opening-out angle, e.g. 110°, of the wedge- shaped fan formed by the liquid issuing from said nozzle at a high pressure.
• the bladelike-jet nozzles 40 and 42 are mounted in a conventional manner to a frame 80 ( Figure 2) that consists of a container, as this shall be described in greater detail further on.
• the air filtering unit 50 is comprised of a rigid load-bearing structure 52 in a preferably rectangular shape, to which there is attached a cloth 54 made of a medium-porosity (e.g. not in excess of 50 ⁇ m), single-yarn woven fabric or, anyway such fabric having a porosity allowing it to effectively retain such thin particles as lint.
• the air filtering unit 50 is accommodated within the frame 80 and is retained thereinside by means of a hinge ⁇ 2.
• This hinge ⁇ 2 is located at an end portion of the frame 80 lying opposite to the one at which the bladelike-jet nozzles 40 and 42 are mounted, so that the air filtering unit 50 is capable of also coming to lie in a position in which it is aligned with the spray plane of the bladelike-jet nozzles 40 and 42 thereabove.
• the actuator means 60 is associated to the air filtering unit 50 in such manner as to enable the air filtering unit 50 to be actuated into performing a relative movement with respect to the frame 80.
• the actuator means 60 is secured to the frame 80 using conventional fastening means, and it is connected to the air filtering unit 50 via a connecting rod 62 and a crank 64 ( Figure 2).
• the control unit 70 controls the operation of the electromagnetic valves 22 and
• control unit 70 implements a firmware and holds data in a storage memory as required for enabling an application programme to be carried out.
• Figure 2 is a schematic side view illustrating a kinematic arrangement provided to cause the air filtering unit 50 to oscillate, i.e. to be brought into a swinging movement automatically.
• This kinematic arrangement forms an articulated quadrilateral of a crank-rocker arm type.
• Such articulated quadrilateral is formed of the crank 64, which has an end portion ⁇ 1 that is firmly joined to the shaft (not shown) of the actuator means 60 perpendicularly thereto, the connecting rod 62, which has its two end portions rotatably connected to the crank 64 and a side of the bearing structure 52 of the air filtering unit 50, respectively, the air filtering unit 50 itself, which is linked to the frame 80 by means of a hinge ⁇ 2, and - finally - the segment that, while joining ⁇ 1 with ⁇ 2, closes the articulated quadrilateral.
• the actuator means 60 acts directly upon the crank 64 to thereby cause it to perform complete revolutions at an angular velocity ⁇ 1 , whereas the air filtering unit 50 rotates in accordance with its hinge-type linkage ⁇ 2 at an angular velocity ⁇ 2 to thereby perform a swinging movement involving oscillations of a given extent passing through a starting position with reference to the air filtering unit 50.
• Such starting position may in this case be defined, for example, as the position in which the air filtering unit 50 is inclined by some degree, relative to the spray plane of the two bladelike-jet nozzles 40 and 42 located thereabove, towards the actuator means 60.
• the swinging movement of the air filtering unit 50 relative to the nozzle 40, 42 enables the surfaces of the same air filtering unit to be progressively flushed, and cleaned, starting from the upper end portion of the air filtering unit itself.
• This solution is particularly advantageous, since the jet issuing from the nozzle is capable of more effectively hitting each portion of the air filtering unit, while producing a kind of brushing action from the top to the bottom, which is effective in facilitating the separation of the lint for the latter to be then removed and let off.
• the frame 80 is comprised of a container provided with a conduit having an appropriately sized cross-section area for letting in the air to be filtered F1 , and a conduit having an appropriately sized cross-section area for letting out the filtered air F2. Between these conduits there is located the air filtering unit 50. Each one of said two conduits is provided with a respective connection mouth adapted to connect to a ventilation circuit, wherein air-tightness is in each case ensured at each such connection by means of appropriate gaskets.
• the frame 80 further comprises a drain system (not shown) provided to let off the liquid mass used to flush, and wash, the air filtering unit 50.
• the structure of such frame 80 is so designed as to enable it to fit, i.e. adapt to the whole assembly of functional parts and elements forming a tumble dryer and, in particular, to enable it to be located upstream to the heat exchanger that is provided for the water vapour contained in the moist air to condense thereon.
• the drain system which the frame 80 is provided with, leads into a collecting tank 90, which a drain pump 92 is associated to for said tank to be properly emptied as needed.
• the control unit 70 causes the mass of liquid to flow into the reservoir 10 by switching the water-flow adjustment means 22 into opening.
• a sub-routine may be run or some other suitable measure can be taken to select whether or not the conduit 29 has to be shut through the water-flow adjustment means 24.
• the flushing process for cleaning the air filtering unit 50 starts as soon as the mass of liquid filled into the reservoir 10 reaches up to an adequate amount for such process to be carried out, e.g. one liter. In this initial phase of the process, the air filtering unit 50 is in its starting position as defined hereinbefore.
• the control unit 70 enables the pump 30 to deliver the above-cited mass of liquid to the bladelike-jet nozzles 40 and 42, preferably in a pulsed sequence so as to bring about a kind of chiseling effect on the air filtering unit 50. Concurrently, the control unit 70 causes the actuator means 60 to actuate the afore-described kinematic arrangement illustrated in Figure 2.
• the air filtering unit 50 itself swings to slowly and gradually incline by an angle ⁇ , as determined by the constraints of the mechanism, relative to the spraying plane of the bladelike-jet nozzles 40 and 42, to eventually move back into its starting position under reversal of the direction of ⁇ 2.
• the curtain or film of liquid mass that issues under pressure from the bladelike-jet nozzles 40 and 42 will have scanned the entire surface of a face of the air filtering unit 50.
• the spraying plane of the bladelike-jet nozzles 40 and 42 is such as to affect a single face of the air filtering unit 50, since it is generally assumed that just a single face needs to be cleaned, actually.
• the inventive automatic cleaning arrangement for air filters is in fact preferably designed for use in the drying circuit in a clothes drying machine operating on a heat-pump principle and, therefore, the lint released by the clothes during the drying process tends to solely settle on a single face of the air filtering unit 50.
• the air filtering unit 50 is flushed clean preferably upon conclusion of a clothes drying process, i.e.
• drain pump 92 is assigned the task of letting off the mass of liquid used to flush clean the filtering unit, and collected into the collecting tank 90, e.g. under control of the control unit 70.
• the actuator means 60 may swingably actuate the bladelike-jet nozzles 40 and 42, whereas the air filtering unit 50 remains stationary, i.e. is excluded from such actuation, or two actuating means 60 may be used to swingably actuate both the air filtering unit 50 and the bladelike-jet nozzles 40 and 42, respectively, in a properly coordinated manner.
• the air filtering unit 50 may be hinged either at a location close to the end portion of the frame 80, where also the bladelike-jet nozzles 40 and 42 are mounted, or in a different position.
• bladelike-jet nozzles 40 and 42 which may be mounted or linked to the frame in any suitable manner whatsoever.
• they may for example be provided so as to slide on runners (shoe-and-rail type of linkage).
• the driving or actuating shaft of the actuator means 60 may be positioned so as to coincide with the hinge.
• the actuator means - as generally understood to include the whole assembly of the parts and members adapted to generate the above- mentionaed movement - may itself be driven by means of a cam drive.

Landscapes

• Engineering & Computer Science (AREA)
• Textile Engineering (AREA)
• Detail Structures Of Washing Machines And Dryers (AREA)
• Filtering Of Dispersed Particles In Gases (AREA)
• Grinding-Machine Dressing And Accessory Apparatuses (AREA)
• Treatment Of Fiber Materials (AREA)
• Prevention Of Fouling (AREA)

Applications Claiming Priority (2)

Publications (3)

Family

ID=39924925

Family Applications (1)

Country Status (5)

Families Citing this family (27)

Family Cites Families (5)

• 2007
  • 2007-08-01 IT IT000056A patent/ITPN20070056A1/it unknown
• 2008
  • 2008-05-22 AT AT08759931T patent/ATE504688T1/de not_active IP Right Cessation
  • 2008-05-22 DE DE602008006082T patent/DE602008006082D1/de active Active
  • 2008-05-22 EP EP08759931A patent/EP2171151B8/en not_active Not-in-force
  • 2008-05-22 WO PCT/EP2008/056330 patent/WO2009015919A1/en active Application Filing

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