FR2695415A1 - Process for spinning wet laundry. - Google Patents

Abstract

In order to optimally adapt the spinning to a given quantity and type of laundry as well as to the distribution of the laundry load inside the drum, the stiffness of the ramp is varied according to the invention. speed (alpha), the final rotation speed (nE) and the spinning time (tR B to tS E) depending on the quantity and / or the nature of the drum load and the value of the unbalance.

Description

Process for spinning wet laundry.

  The present invention relates to a process for spinning lin-

  wet in a drum washing machine with, at the start of the test cycle

  sorage, an operational phase during which

  ner the drum at a measuring rotation speed which is lower than the resonance rotation speed and for which the laundry is already

  applied against the wall of the drum and the unbalance of the drum is measured

bour loaded.

  The German patent application published under No. 40 22 715 discloses a spinning method of this type in which the consecutive operating phase of the spinning cycle takes place with a

  final rotational speed greater than the rotational speed of reso-

  nance, chosen between two limit values according to the unbalance value considered as admissible and determined during the measurement phase This phase of the spin cycle is used, it is true, to pre-drip the load of laundry whose unbalance is controlled again during a measurement phase It is only after having observed an admissible unbalance of low value that the spin cycle itself, with a final rotation speed higher than

  rotational speeds set so far, is triggered.

  A known spinning method of this type has the disadvantage

  deny following a fixed curve preset for the main spin cycle All laundry loads are treated in the same way

  during this spin cycle, on the one hand, the risk of deterioration

  delicate items of laundry and, on the other hand, for a number of loads

  laundry that is ill-suited to this preset curve, a result of

  sorage or a treatment duration which leaves something to be desired Furthermore, the damping devices mounted in a washing machine must be designed for the most unfavorable ratio between the fixed main spin curve and the corresponding laundry load, resulting in significant expenditure that could be avoided. The object of the present invention is to improve a spinning process described in the introduction so that the profile of the spinning phases can be adapted individually to the loads of laundry to be treated so as to allow on the one hand to save the laundry and on the other hand to get a better spin and reduce expenses for

  damping devices in washing machines.

  The problem is solved according to the invention by the fact that the stiffness of the speed-up ramp and the spin time are also varied during the operating phase or phases of the

spin process.

  As will be explained below, these provisions

  feels a softer treatment of the laundry, not only because the laundry is spun only the time actually necessary to obtain a desired removal of moisture from the laundry, but also because of particular loads of laundry, upper end of the ladder

  sensitivity, can still be treated with sufficient softness

  te In addition, these provisions reduce the number of climb tests

  speed and improve the stability of the washing machine thanks to an appreciation

  more precise conditions resulting from the type of laundry, its repair-

  tition and initial humidity Studies over a long period of

  riode have shown that the final rotational speeds reached during the main spin cycle are on average higher and that, as a result, residual humidities are obtained on average lower,

  therefore better spin results.

  According to an advantageous improvement of the method according to the

  vention, the spin time is adjusted according to the quantity and / or

  the nature of the drum load.

  According to another improvement of the method according to the invention, the stiffness of the ramp is adjusted as a function of the quantity and / or the nature of the load of the drum as well.

than the value of the unbalance.

  In accordance with another advantageous improvement of the invention, the final speed of rotation is adjusted according to the

  quantity and / or nature of the drum load as well as

  tion of the unbalance value. The process according to the invention is described below in detail using a diagram of the spin program shown.

on the drawing.

  Insofar as provisions are provided in a washing machine

  which determine the quantity and / or the nature of the char-

  age of the drum, the spin time will depend on the amount of

  and / or the nature of the drum load The spin time

  is adjustable between the limits t SE, and t SE 2 The nature of the lin-

  ge determines the spin time, for example in the sense that fabrics

  sup whose fibers retain little water, such as synthetic fabrics, lead to a closer adjustment of the spin time

  of the lower limit t SE 1, while fabrics whose fibers retain

  a relatively large amount of water, such as cotton fabrics, leads to a setting of the spin time closer to the upper limit t SE 2 The amount of laundry also influences the

  choice of spin time; indeed, compared to a load of lin-

  smaller age, a relatively large load of laundry opposes greater resistance to the flow of water to be expelled through the fabric This is why, a large load of laundry must be spun longer than a load of laundry smaller We can establish, at

  from these two parameters quantity and nature of the load of the tam-

  bour, a matrix-type table showing different spin times

ge t SE-

  The choice of the stiffness of the ramp up between

  the limits al and cc 2 is decisive for improving the stability of the

  washing machine and is important to limit the number of climb attempts

  speed If during the TU unbalance determination phase,

  tect an admissible unbalance of high value, it is preferable to have

  a faster increase in speed, following a steeper ramp of an-

  gle cc 2, only in the case of a weaker unbalance.

  The concept of unbalance characterizes the situation in an im-

  precise given that this, as a result of an interrogation

  tion performed during the unbalance measurement phase Tu with a naked rotation speed lower than the resonance rotation speed, contains in itself two parameters One of these parameters is the unbalance

  in kg-mass which is not distributed centrally This concept en-

  globe also the parameter "quantity of charge" (= total mass)

  which must be accelerated and which gives additional inertia to the system

  vibratory me A high total mass has a great inertia and naturally reduces the influence of a poorly distributed mass So there is

  relationships between the unbalance and total mass actions.

  In accordance with the invention, these relationships are taken into account during

  of the ramp stiffness selection A less steep ramp pre-

  however, feels the advantage of allowing a longer pre-draining, so that the total mass "linen + water", before reaching the final speed of rotation, can be significantly lower than in the case of a

steep ramp.

  Similar interdependencies also exist when the final rotation speed of the main spin cycle is reached. It is therefore advisable to adjust the final rotation speed as a function of the quantity and / or the nature of the load of the drum as well as of the unbalance value A relatively high weighted unbalance

  by the quantity of the charge therefore leads to the adjustment of speed of ro-

  weaker final tations, close to n El, and conversely an unbalance

  lower results in higher final rotational speeds,

ches of n E 2.

  The interdependencies between unbalance and load are not only

  Lement function of the nature and the quantity of linen but also of certain parameters of construction of the machine We develop from these parameters algorithms which determine the stiffness of

  the ramp, the final speed and the spin time The method

  for determining the unbalance and the nature and / or the amount of the load does not constitute the subject of the invention and can be freely

  chosen The method currently applied today uses the

  rotational speed ratios which can be measured at the tachometer generator of the drum drive motor The nature and quantity of the load can also be determined differently from program processing parameters

  previously carried out.

* And 6

Claims (4)

  1 Process for spinning wet laundry in a washing machine   drum comprising, at the start of the spin cycle, a function phase   operation during which the drum rotates at a rotational speed   tation which is lower than the resonance rotation speed and for which the linen is already applied against the wall of the drum and the unbalance value of the loaded drum is measured, as well as an operating phase of the spin cycle with a speed of final rotation greater than the resonance rotation speed which is set between   two limit values depending on the measured unbalance value, pro-   assigned characterized by the fact that the stiffness (oc) of the speed ramp can be varied (t RB to t SB) and the spin time (ts B) to   ts E) of the operating phase (s) (t "to t SE) of the test cycle   sorage. 2 Method according to claim 1 applied to a washing machine which comprises devices for determining the quantity and / or the nature of the load of the drum, characterized in that one adjusts   the spin time (t SB to ts E) depending on the quantity and / or the load of the drum.   3 Method according to claim 1 or 2, characterized in that one adjusts the stiffness (oc) of ramp up speed (t RB to   ts B) depending on the quantity and / or the nature of the load of the tam- bour and the unbalance value.   4 Method according to any one of claims 1 to 3,   characterized in that the final rotation speed (at n E 2) is adjusted as a function of the quantity and / or the nature of the load of the drum and of the unbalance value.