GB2027876A - Improvements in and relating to ventilation and cleaning of looms - Google Patents

Abstract

In a loom having provision for ventilation, the rate or direction or temperature or humidity of the air flow through a ventilation duct (17, 30) is controlled by a programmer (41). This makes it possible to operate on a weak flow of, for example, extraction air during normal weaving, with a correspondingly low electricity consumption by the motor driving the or each fan, the weak flow being supplemented intermittently (for instance, once or twice daily) by a short intense flow of suction air to clean the machine thoroughly, more particularly of the relatively heavy lint deposited on parts of the loom during weak flow operation. Air extraction is indicated at 28, 28b. Alternatively air may be injected as indicated at 28a or may be alternately extracted and injected. <IMAGE>

Description

SPECIFICATION Improvements in and relating to looms This invention relates to a method of operating a loom having provision for ventilation and to a loom which is adapted to perform the method.

Looms have already been proposed with ventilation means incorporating air conditioning. When operation begins with a particular kind of yarn the air conditioning facility is adjusted to particular values of rate of flow of air, temperature and humidity, whereafter these values remain unchanged until they are reset, for example to suit a different yarn. This form of operation makes operation of the conditioning facility relatively expensive.

According to one aspect of the present invention, in a method of operating a loom having provision for ventilation, the air for at least one ventilation duct has at least one parameter program-controlled. Parameters which may be controlled include rate of flow, direction of flow, temperature and humidity.

According to a second aspect of the invention, a loom has a ventilation duct associated therewith, means for adjusting at least one parameter of the air flowing in the duct, and a programmer controlling the adjusting means.

By means of the invention, it is possible to reduce the energy required for operation by more closely matching the ventilation to theoretical requirements. For example, where the parameter or one of the parameters is the rate of flow in the duct, the program may provide periods of normal low rate of flow interspersed with shorter periods at a higher rate of flow. For example, an intense flow of extraction air can be provided for approximately one minute as seldom as every twelve hours while for the remainder of the time there is a much lower air flow for which the motor driving the fan producing the flow consumes little power. The intense pulse of air will be selected to be sufficient to remove accumulated lint and other debris which may, for example, include heavy particles which have dropped in the previous weak air flow and settled on parts of the loom.

The invention may be carried into practice in various ways but one loom embodying the invention, together with its operation, will now be described by way of example with reference to the accompanying diagrammatic drawings, in which: Figure 1 is a diagrammatic elevation of the loom seen from the cloth end; and Figure 2 is a plan view of the loom.

In the loom 1 shown in the drawings, the weft thread 2 is picked by means of a gripper projectile 3. The weft thread 2 is drawn off weft yarn supply bobbins 19 which remain outside the shed while the loom is in operation, and reaches the projectile feeder via a drum type temporary weft store 1 6 in which for each pick a length of weft yarn sufficient for the cloth width is in store. The finished cloth is taken up on a cloth beam 1 0. At the warp end and cloth end the loom is covered by flaps 4. The loom has two side frames or cheeks 5, 6.

Secured to the side frame 5 is a bobbin creel 7 supported by a post 8. The bobbins 19, the temporary weft store 1 6 and other elements which are not shown, such as yarn guides, yarn brakes and so on, together make up a weft supply facility 22 and this is covered by a hood 1 7 pivotally connected to the side frame 5 by a hinge 24 so that it can be swung up into the position 1 7a shown in chain-dotted lines for access to the bobbins 19, store 16 and so on.

A plate 21 pivotally connected to the side frame 5 by a pivot 26 with a vertical axis and serving to catch lint is disposed below bobbins 1 9 and store 1 6 and can be swung out into a position 21 a.

The hood 1 7 is connected to an extraction duct 30, so that in operation there is a flow of air in the direction indicated by arrows 28 past and/or through the weft supply facility 22. The weaving shed can therefore be kept very clean.

The conditioning facility 17, 30 comprises a damper 42, a fan 43 and a programmer 41, the latter being shown diagrammatically. The programmer 41 can be adjusted, for instance, so that the fan 43 is switched to high-speed operation for a short period of, for example, one minute approximately every 1 2 hours.

Considerable suction is therefore produced within the hood 1 7 and the duct 30 so that heavy lint and fly particles and agglomerations which have been deposited over the preceding 1 2 hours are lifted and carried carried along by the air flow and removed.

The programmer 41 then resets the fan 43 to a low speed to give a weak air flow through the hood 1 7 and the duct 30. The motor driving the fan 43 consumes little electricity when operating in the low-speed or economy mode.

As an alternative, it is possible to arrange for the programmer 41 to stop the fan 43 completely between consecutive cleaning phases of intense air flow.

In another alternative, the fan 43 runs at the same speed the whole time but the air flow through the duct 30 is briefly peaked.

The peaking is controlled by the programmer 41 by way of a line 44 enabling a servomotor (not shown) to adjust the damper 42. The programmer 41 can be an electric programmer.

In other possible arrangements, air may be delivered to the hood as an alternative to or in addition to the suction. In such cases, the temperature and/or the humidity of the air flow can be programmed.

The space below the flaps 4 can also be connected to the suction air flow (arrows 28b). If required, air for cleaning and/or conditioning can be injected in the opposite direction (arrows 28a), the programmer 41 controlling, for instance, the rate of flow of air thus injected. For instance, the air injected in the direction indicated by the arrows 28a can be injected briefly, possibly for a minute, as an intense pulse, whereafter 59 minutes of economy operation on a weak air flow follow.

Also, a strong pulse for cleaning can be produced, for instance, for one minute in the direction of the arrows 28, 28b, whereafter a weak conditioning air flow in the opposite direction is provided for 59 minutes in the direction indicated by the arrows 28a In a loom having a number of air ducts, a programmed changeover between the various ducts can be arranged. In the case of a relatively well sealed loom a desired climate below the flaps 4 can be maintained fairly easily by periodical renewal by short intense pulses of air interspersed with longer periods of weak flow operation.

The various arrangements described for a single loom can be used with advantage for a relatively large number of looms in a mill; in such cases, the air for all the looms may be programmed simultaneously and in the same way.

Claims (9)

1. A method of operating a loom having provision for ventilation, in which method the air for at least one ventilation duct associated with the loom has at least one parameter program-controlled.

2. A method as claimed in Claim 1 in which the parameter or one of the parameters is the rate of flow in the duct.

3. A method as claimed in Claim 2 in which the program provides periods of normal low rate of flow in the duct interspersed with shorter periods at a higher rate of flow.

4. A method as claimed in Claim 1 or Claim 2 or Claim 3 in which the flow in the duct is a suction flow.

5. A method as claimed in Claim 1 in which the flow in the duct is a delivery flow and the parameters are temperature and humidity.

6. A method of operating a loom substantially as described herein with reference to the accompanying drawings.

7. A loom having a ventilation duct associated therewith, means for adjusting at least one parameter of air flowing in the duct, and a programmer controlling the adjusting means.

8. A loom as claimed in Claim 7 in which the duct is a suction duct and the adjusting means is means for adjusting the rate of flow in the duct.

9. A loom substantially as described herein with reference to the accompanying drawings.