FR2632985A3 - HOUSEHOLD TYPE DRIER - Google Patents

Abstract

The invention relates to household appliances. In this dryer, we reduce or eliminate the noise produced by the change of direction imposed on the air when it enters the fan, by placing at the coaxial inlet of the fan volute a static deflector 14 comprising radial vanes curved which gives the deflector the shape of a flower. Main application: household clothes dryers, open or closed circuit drying air.

Description

The present invention relates to a household dryer machine, the

rotary drum type and equipped

of an improved silencer.

  This type of machine essentially comprises a fan which draws air into the atmosphere outside the machine and sends it through heating devices, then through the drum containing the laundry and, finally, into a duct. the discharge of air into the outside atmosphere, if the machine is of the open circuit type for drying air, or to a group

  condensation cooled by air or water if the

  China is of the closed circuit type for dry air.

ge.

  In both types of operation, the aspira-

  air from the outside atmosphere gives rise to an annoying noise. caused by the abrupt change of direction that the suction fan, generally of the centrifugal type, imposes on the flow of air, since

  the air is sucked from the outside in a first direction

  tion, and is forced back into the machine ducts in a direction almost orthogonal to the direction of suction. This noise is more intense in cases where the

  fan is placed in the immediate vicinity of the

  suction line and must discharge a large air flow for an open air circuit such as, for example,

  the cooling circuit of the cooling group

densation.

  Indeed, under the conditions indicated below

  the noise caused by the fan and the

  air is spreading to the outside atmosphere

  without being advantageously stopped by the body of the

  like, on the contrary, in the cir-

closed air drying.

  In addition, this type of noise caused by the

  tilator and by swirling motion and. turbulent

  slow air is particularly noticeable if

  suction lines are provided in the border section.

  of the machine, to satisfy the search for solu-

  for built-in appliances without penalizing the suction

machine.

  In general, machine builders

  tumble dryers intervene on this type of noise

  so many liners and covers in phono-absorbent material

  (eg, felt or equivalent) the parts of

  ducts located in the suction area of the fan

  tor. However, these sound absorbing devices are

  difficult to mount and require fastening systems

  which complicate assembly and

maintenance of the machine.

  It would therefore be desirable, and this constitutes the main object of the invention, to provide a dryer machine in which the noise of air suction is reduced or at least reduced to a minimum and o, at the same time time, we improve the rationality and the

  simplicity of assembly and maintenance of the machine

born.

  These and other goals are achieved,

  the invention, in a dryer machine, in particular

  household type and rotating drum with horizontal axis

  zontal, comprising an indoor air circuit connected to the outside atmosphere through at least one opening

  of suction arranged coaxially with a fan of ty-

  centrifugal pump which is able to draw outside air and

  to push it back through said air circuit according to a di-

  substantially orthogonal to the direction of the

  drawing, characterized in that said opening of

  ration is equipped with a static deflector suitable for

  sea a helical rotation to the fluid streams of the air

sucked by the fan.

  Figures in the attached drawing, given only

  by way of example, make it clear how

  vention can be realized. In this drawing, FIG. 1 is a view partly in section of a part of the front wall of a tumble dryer according to the invention

  Figure 2 shows a longitudinal section se-

  lon line II-II of Figure 1; -

  FIG. 3 represents an enlarged detail of the

figure 2.

  The dryer machine 3 shown in the figures

  of the drawing and the rotary drum type with a horizontal axis

  zontal and closed circuit for drying air.

  The machine 3 comprises essentially an outer furniture 4 inside which is housed the drum intended to contain the laundry, a closed circuit for air

  drying and an open circuit for cooling air

  condensation device not shown.

  The machine is equipped with all the devices

  caniques and electrics necessary for its

  These devices are sufficiently well known

their superfluous description.

  In particular, the front wall 6 of the machine

  -3 has suction slots 8 provided in the zo

  furniture 4 which is below the opening 7

  loading laundry into the drum 5.

  At its suction slots 8, the

  china 3 contains a suction unit for the air required

  to the cooling of the. condensing device mentioned above. The suction group includes a fan

  centrifuge mounted in a volute housing 10 and

  born by an electric actuating motor 11 (FIG.

2).

  The housing 10 of the fan 9 has an opening

  circular suction line 12, coaxial with the turbines

  9 and connected to the aforementioned condensing device by a conduit 13 which has, in its initial part, a shape almost orthogonal to the direction of air which

  through the slots 8 and the suction opening 12.

  In a traditional tumble dryer, this sudden

  change of direction causes a swirling motion-

  in the stream of air sucked by the turbine 9 and, consequently, an undesirable increase in the noise of

the machine.

  In the tumble dryer according to the invention, this type of noise is on the contrary eliminated or at least reduced to a minimum by the adoption of a static deflector 14

  placed at the right of the suction opening 12 of the tur-

  9. This deflector 14 essentially presents the

  of a "flower" (Figure 3) and includes a peripheral edge

  15, a central rod 16 and a plurality

  radial vanes 17 fixed between the edge 15 and the tread

  16, with an inclination of approximately 45 on the

  limited by the suction opening 12.

  The radial vanes 17 impose on the fluid streams suctioned air a rotation which is advantageous

  for the quiet operation of the machine.

  During laboratory tests, we have indeed

  have been able to verify that the fluid streams of the

  by the turbine 9 reach the curve in the form of

  of the suction duct 13 with a proper angle to

  both the formation of vortices and turbulence

  the noise that derives from these whirlwinds and tur-

bulences.

  In addition, it was also possible to verify that

  flector 14 provides an efficient stopping action towards the ex-

  the residual noise of the machine.

  Indeed, the sound waves that tend to

  spread out through the suction opening

  12 are largely reflected in the

  the machine by the radial pallets 13 of the de-

flector 14.

  The deflector 14 is mounted as an example

  above the air intake opening 12 of the air

  cooling for the condensing device but it is obvious that it could also be advantageously

  used on other possible openings in the machine.

  3. It has thus been possible to achieve the aims of the invention of reducing in a simple and rational way

  the suction sound of the device. without resorting to

  phono-absorbent materials that are uncomfortable for both assembly operations and

  for maintenance operations of the machine 3.

  It goes from ground up that various modifications and va-

  can be made to deflector 14, including

  by substitution of equivalent technical means, without departing from the scope of the invention. For example, the deflector 14 can also be made as an integral part of the suction slots 8, in the case where the volute housing 10 of the turbine 9 is made in close contact with the front wall 6

from the machine.

R E V E N D I C k T I 0 N S

  1. Dryer machine, in particular of the household type

  ger and rotating drum with horizontal axis, comprising a

  internal pneumatic circuit connected to the external atmosphere

  through at least one metal suction opening

  coaxially ventilated with a centrifugal type fan that is able to take in the outside air and push it back

  through said air circuit in a direction substantially

  orthogonal to the direction of aspiration,

  characterized in that said suction opening (12) is provided with a static deflector (14) adapted to print

  a helical rotation to the fluid streams of the air as-

blown by the fan (9).

  2. tumble dryer machine according to claim 1, characterized in that said deflector (14) has the shape of a "flower" and comprises a rounded peripheral edge (15), a central rod (16) and a plurality of pallets (17) arranged radially between the edge (15)

  the rod (16) and inclined substantially by 45

  port to the plane defined by the suction opening (12).