FR2494733A1 - DEVICE FOR THE INTRODUCTION OF LAUNDRY PIECES, IN PARTICULAR IN AN IRONING MACHINE - Google Patents

Abstract

1. Apparatus for feeding laundry pieces, particularly to an ironing machine, of the type comprising a conveyor (1), at the upstream end of which is provided at least one pair of grippers (3, 4; 5, 6), able to move transversely with respect to the feed direction of the conveyor (1) and able to grip a laundry piece by two of its corners, means (11 to 28) being provided for driving the two grippers of each pair, with a view to separating them from each other in order to stretch the laundry piece gripped and to bring this laundry piece into a centered position with respect to an axis (8) defined in advance, characterised in that the means for driving the two grippers of each pair are arranged in order to move, in a first stage, a single gripper (3) until the laundry piece is stretched and then to move the two grippers (3, 4) simultaneously, in a second stage, until they are brought into a symmetrical position with respect to the centering axis (8) under the control of means (30, 31) detecting the movement (X, X') of the first gripper (3) and reacting to tensioning of the laundry piece.

Description

I

  The present invention relates to a device for

  both the introduction of items of linen, such as

  sheets especially in an ironing machine. More particularly

  In particular, this device is one of those

  a conveyor at the upstream end of which is provided at least one pair of clamps, movable transversely to the direction of advance of the conveyor, and capable of grasping a piece of laundry by two of its angles, means being provided for the driving the two clamps of each pair, in order to move them away from one another to tension the piece of seized laundry, and to bring this piece of laundry in a position centered with respect to an axis defined in advance, which is not necessarily the axis of the conveyor.

  This kind of device makes it possible

  laundering operations, to adequately

  pieces of laundry, before introducing them into a machine

  do not iron. A device currently known

  According to the following principle: In a first step, the two grippers of the same pair, having grasped a sheet, move simultaneously from a lateral loading station to the center of the device. -In a second step, these two clamps part one

  on the other until the sheet is stretched.

  The implementation of this principle leads to a complex realization, as regards the control and the control of the movements of the two clamps, and in particular of which the direction of displacement is reversed between the

two phases of operation.

  The present invention overcomes this disadvantage, by providing an improved device of the kind defined above, wherein the drive means of the two clamps of each pair are arranged to move, in a first phase, a single clamp until the piece of cloth is stretched, and then simultaneously move the two clamps in a second phase, to bring them into a position symmetrical with respect to the centering axis under the control of means detecting the moving the first clamp

  and reacting to the tensioning of the piece of laundry.

  Preferably, the means for detecting the displacement of the first clamp translate this displacement into

  impulses, operated using a counter that

  one-in-two impulse during the first phase

  se, that is to say between the start of the first clamp and the instant when the piece of laundry is stretched, and which counts all the pulses during the second phase, that is to say from moment the piece of linen is stretched and the second clip is also driven, the content of the meter being compared to a fixed value such that at the moment when the equality is obtained, the two clamps have reached their symmetrical position

relative to the centering axis.

  The counter can work by countdown, and in

  this case it is interesting to foresee that its

  tial is equal to the difference between, on the one hand, the distance separating the rest position of the second clamp and the centering axis, and on the other hand, half of the initial spacing of the two clamps, so that the centering is obtained at the precise moment when the content of the counter is canceled, as will be demonstrated later. The means for detecting the displacement of the first clamp are constituted, for example, by an optical pulse generator, associated with the drive means

of this first clip.

  According to a particular embodiment of the invention, the two grippers of the same pair are

  through transmission elements

  of two separate engines, the generation of

  The optical pulse generator is mounted to detect the displacement of the transmission element driving the first clamp, while the second clamp cooperates, in the rest position, with a presence detector. This detector reacts, to change the counting mode of the pulses, when the sheet being stretched, the first clamp begins to draw the second through the sheet. The two clamps can be connected, in particular via cables

  without end passing over pulleys, two

electric brakes *

  According to another possible embodiment, only

  the first clamp of each pair is driven, via an endless transmission element, from a motor, the second clamp being provided with means enabling it to be locked on said element of

  transmission during the second phase of

  ment. By means of a kind of clutch mechanism,

  the training system can thus be further simplified.

  is lying. In any case, the invention will be better understood

  using the following description, with reference to the

  attached schematic sin representing, by way of non-limiting example, an embodiment of this device for the introduction of items of laundry, especially in an ironing machine; Figure 1 is an overview in perspective, very

  schematic, of a device in accordance with this

vention;

  Figure 2 represents, in particular, the mechanism

  drive and centering of one of the two pairs of clamps of this device; Figures 3,4 and 5 are explanatory diagrams of the

  operation of the device under consideration.

  The device visible in FIG. 1, intended to feed pieces of laundry, such as sheets, a

  downstream ironing machine, not shown,

  takes a conveyor 1 bringing the pieces of laundry to said machine. To properly spread these parts on the conveyor 1, are provided pressing discs 2 and especially two pairs of clamps 3, 4 and 5.6, located upstream of the rear end of the conveyor 1. All these clamps 3 to 6 are movable transversely to the direction of advancement of the conveyor 1, along a sliding rail 7 (see FIG. 2), and the present

  invention is concerned, in particular, with the mechanis-

drive these clips.

  The mechanism in question is shown in the figure

  re 2, only for the clamps 3 and 4 which constitute the first pair and which, in rest position are

  rows near the left end of the slide rail-

  7, outside the width of the conveyor 1, this working width being designated Dar E. The other two clamps 5 and 6, which constitute the second pair

  and which, in the rest position, are arranged near the ex-

  straight end of the sliding rail 7, are

  born by symmetrical means, with respect to the plane

  dian represented by axis 8, of those appearing on

Figure 2.

  Each of the clamps 3 to 6 consists of a carriage

  9 rolling on the rail 7, and two jaws 10 constituting

  killing the clip itself, designed in such a way as to

  see, for example, tighten the angle of a sheet.

  The carriage 9 of the clamp 3 is secured with an endless drive cable 11 shown in dashed lines. This cable 11 passes on various return pulleys 12 to 17, as well as on a driving pulley 18 coupled to a first brake motor 19. Similarly, the carriage 9 of the clamp 4 is secured to an endless drive cable 20 , shown in phantom; this cable 20 passes over various return pulleys 21 to 26, as well as on a driving pulley 27 coupled to a

second brake motor 28.

  The cable 11 used to drive the clamp 3 passes over an additional pulley 29, coupled to a

  - optical pulse generator 30. This generator, as-

  an electronic counter of itpulsions, measures the

  movement of the cable 11, therefore of the clamp 3.

  The other clamp 4 cooperates with an electrical contact

  31 placed at the end of the rail 7, and detecting the presence or absence of this clamp 4 at its stop position.

  Both engines 19 and 28, the generator set

  pulse counter 30 and the presence contact 31

  are connected to a central control box 32.

  To use the device, the operator introduces

  duit two angles of the sheet in the jaws 10 of

  two clamps 3 and 4, initially arranged near the ex-

  left end of the rail 7. When both clamps 3 and 4 are loaded, the brake motor 19 is started, while the brake motor 28 is unlocked. The clamp 3 is thus moved, in the direction of its distance from the clamp 4 which initially remains stationary, at its stop position. The sheet is deployed and when it is stretched, it begins to trap the clamp 4, which then leaves the stop station and causes the actuation of the

presence contact 31.

  At this time, the motor 28 starts for a very short time, to give its speed to the clamp

  4. The clamp 3 then entrains the clamp 4, via

  diaire stretched sheet, until the two clamps 3 and 4 are centered, that is to say, reach positions in principle symmetrical with respect to the axis 8. The two motors 19 and 28 are, at at this moment, braked so as to immobilize the two drive cables II and 20, as well as the two clamps 3 and 4, and the sheet is itself centered, in the extended position. This sheet can then be spread on the conveyor

1 and separated from the jaws 10.

  In order to obtain the exact centering,

  the generator-pulse counter assembly 30 in the manner to be described hereinafter with reference to the diagrams of FIGS. 3 to 5, in which: A denotes the initial spacing of the two clamps 3 and 4; B denotes the distance separating the stop station from the clamp 4 of the axis 8 of the device; -L denotes the length of the piece of linen;

  Y represents the displacement of the clamp 3, between the

  both the start of the motor 19 and the moment when the sheet D is stretched, so during the first phase; and -xI represents the movement of the clamp 3, as well as

  that of the forceps 4, between the instant when the sheet is

  from and the moment the sheet is finally centered, so

during the second phase.

  The contents of the pulse counter are initially

  In the first phase of operation illustrated by the diagram of FIG. 3, a countdown starts and is carried out as follows: the content 0 of the counter decreases by one. unit for receiving two

  pulses from the optical pulse generator 30.

  The content of the counter is given by the formula:

C X P (X / 2).

  This countdown of one pulse in two continues until the moment when the drape D is stretched, therefore until the spacing of the two clamps 3 and 4 is equal to the length L (see Figure 4). At this precise moment, the clamp 3 has traveled the distance (ZA), so that the content of the counter is C: _ p _ L-A The contact 31 of presence of the clamp 4 causes, at this moment, a change of counting mode: all the pulses emitted by the generator 30 are counted, therefore the content of the counter is given by the formula: C = p _ LAX As shown in FIG. 5, the displacement X 'of the clamp 3, Agal to that of the clamp 4 since the piece of cloth is stretched, must reach the value XI = B - (L / 2) to reach an exactly centered position. By plotting this last value in the previous formula, it is established that the contents of the counter, at the end of the second phase, will be C = p L A _ (B _ L) = P - (B - 2)

  To detect in a simple way the position of cen-

  trage, in which the two motors 19 and 28 must be braked, it is expected that the content C of the counter is canceled in this position. For that, taking into account the preceding relation, it is enough to provide that the value of preselection of the counter is:

  P, B - (A / 2). We note that this value is a con-

  aunt independent of the length L variable parts

of linen.

  Finally, it will be noted that after opening of the clamps 3 and 4 and engagement of the piece of laundry on the conveyor 1, these clamps 3 and 4 will be returned to their starting position by the respective motors 19 and 28, to allow the similar unfolding. Of the following cycle Of course, the invention is not limited to the sole embodiment of this device which has been described above, by way of example; it embraces, on the contrary, all variants conceived according to the

same principle.

  Thus, in an interesting variant, the motor 28 of the second clamp 4 and the corresponding drive cable 20 are deleted. This

  clamp 4 is then provided with mechanical locking means

  lage on the drive cable 11 of the first clamp 3, these means being triggered when the second clamp 4 begins to be pulled by the first clamp 3, through the stretched sheet. The principle of measurement

  by pulse counting is not changed. This variation

  it has the advantage of allowing the automatic locking of the second clamp, when it leaves its stop station, and it also allows said clamp to unlock itself, when it returns to the stop station . The two clamps are thus driven by a

  the only mechanism, which provides a great deal of simplification

  in comparison with existing systems, and which still allows automatic operation, including to bring the two clamps back into their position

departure.

Claims (7)

-REVENDICATIONS -   1.- Device for the introduction of items of laundry, especially in an ironing machine, of the type comprising a conveyor (1) at the upstream end of which is provided at least one pair of clamps (3,4; , 6), movable transversely to the direction of advancement of the conveyor (1) and capable of grasping a piece of laundry by two of its angles, means (11 to 28)   being intended for the training of the two chain clamps.   to move them away from each other to stretch the seized piece of laundry, and bring this piece of laundry in a position centered with respect to an axis (8) defined in advance, characterized in that that the means   of the two grippers of each pair   to move, in a first phase, a single clamp (3) until the piece of laundry is   tense, and then simultaneously move the two pins   these (3,4), in a second phase, to bring them in a position symmetrical with respect to the centering axis   (8) under the control of means (30,31) detecting the de-   placement (M, X ') of the first gripper (3) and reacting   when the piece of linen is put under tension.   2.- Device according to claim 1, characterized in that the means for detecting the displacement (1,1 ') of the first clamp (3) translate this movement into pulses, operated using a counter which records a pulse on two during the first phase, that is to say between the start of the first clamp (3) and the instant when the piece of laundry is stretched, and which counts all the pulses during the second phase, that is to say that is to say from the instant when the piece of linen is stretched and o the second clamp (4) is also driven, the contents of the counter (C) being compared to   a fixed value such that at the moment * equality is obtained   naked, the two clamps (3,4) have reached their position   symmetrical with respect to the centering axis (8).   3.- Device according to claim 2, characterized in that the aforementioned counter operates by counting,   its initial content (P) being chosen equal to the difference   this enters, on the one hand, the distance (B) separating the posi-   resting position of the second clamp (4) and the center pin.   trage (8), and on the other hand, half of the   initial (A) of the two clamps (3,4), so that the center   trage is obtained at the precise moment o the content (C) the counter is canceled.   4.- Device according to claim 2 or 3, characterized   in that the means for detecting the displacement (X, X ') of the first clamp (3) consist of an optical pulse generator (30) associated with the means   driving (11 to 19) of this first clamp (3).   5.- Device according to claim 4, characterized in that the two clamps (3,4) of the same pair are   through transmission elements   endless transmission (11,20), from two motors dis-   tinets (19,28), the optical pulse generator (30) being mounted to detect the displacement of the transmission element (11) entraining the first clamp (3), while the second clamp (4) cooperates , in   rest positionwith a presence detector (31).   6.- Device according to claim 5, characterized in that the two clamps (3,4) of the same pair are connected by means of endless cables (11,20) passing over the pulleys (12). & 17, 21 to 26),   two electric brake motors (19,28).   7.- Device according to any one of the claims   1 to 4, characterized in that only the first pin-   this (3) of each pair is entralnée, via an endless transmission element (11), from a motor (19), the second clamp (4) being provided with means allowing its locking on said transmission element (11) during the second phase of operation.